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-rw-r--r--kernel/bpf/inode.c7
-rw-r--r--kernel/bpf/stackmap.c8
-rw-r--r--kernel/bpf/syscall.c24
-rw-r--r--kernel/bpf/verifier.c76
-rw-r--r--kernel/cgroup.c63
-rw-r--r--kernel/cpu.c32
-rw-r--r--kernel/events/callchain.c35
-rw-r--r--kernel/events/core.c968
-rw-r--r--kernel/events/internal.h10
-rw-r--r--kernel/events/ring_buffer.c128
-rw-r--r--kernel/fork.c2
-rw-r--r--kernel/kcov.c3
-rw-r--r--kernel/kexec_core.c7
-rw-r--r--kernel/locking/lockdep.c110
-rw-r--r--kernel/locking/lockdep_proc.c2
-rw-r--r--kernel/locking/locktorture.c25
-rw-r--r--kernel/locking/qspinlock_stat.h24
-rw-r--r--kernel/locking/rwsem-spinlock.c19
-rw-r--r--kernel/locking/rwsem-xadd.c38
-rw-r--r--kernel/locking/rwsem.c19
-rw-r--r--kernel/power/swap.c18
-rw-r--r--kernel/rcu/Makefile1
-rw-r--r--kernel/rcu/rcuperf.c655
-rw-r--r--kernel/rcu/rcutorture.c29
-rw-r--r--kernel/rcu/tree.c302
-rw-r--r--kernel/rcu/tree.h20
-rw-r--r--kernel/rcu/tree_plugin.h37
-rw-r--r--kernel/rcu/tree_trace.c13
-rw-r--r--kernel/rcu/update.c4
-rw-r--r--kernel/sched/Makefile1
-rw-r--r--kernel/sched/clock.c48
-rw-r--r--kernel/sched/core.c778
-rw-r--r--kernel/sched/cpuacct.c147
-rw-r--r--kernel/sched/cpudeadline.c4
-rw-r--r--kernel/sched/cpufreq.c48
-rw-r--r--kernel/sched/cpufreq_schedutil.c530
-rw-r--r--kernel/sched/cpupri.c4
-rw-r--r--kernel/sched/deadline.c56
-rw-r--r--kernel/sched/debug.c10
-rw-r--r--kernel/sched/fair.c506
-rw-r--r--kernel/sched/idle_task.c2
-rw-r--r--kernel/sched/loadavg.c11
-rw-r--r--kernel/sched/rt.c39
-rw-r--r--kernel/sched/sched.h148
-rw-r--r--kernel/sched/stop_task.c2
-rw-r--r--kernel/signal.c29
-rw-r--r--kernel/sysctl.c12
-rw-r--r--kernel/time/tick-sched.c13
-rw-r--r--kernel/time/time.c8
-rw-r--r--kernel/torture.c4
-rw-r--r--kernel/trace/power-traces.c1
-rw-r--r--kernel/trace/ring_buffer.c35
-rw-r--r--kernel/trace/trace_event_perf.c3
-rw-r--r--kernel/trace/trace_events.c9
-rw-r--r--kernel/workqueue.c11
55 files changed, 3972 insertions, 1166 deletions
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index f2ece3c174a5..8f94ca1860cf 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -31,10 +31,10 @@ static void *bpf_any_get(void *raw, enum bpf_type type)
{
switch (type) {
case BPF_TYPE_PROG:
- atomic_inc(&((struct bpf_prog *)raw)->aux->refcnt);
+ raw = bpf_prog_inc(raw);
break;
case BPF_TYPE_MAP:
- bpf_map_inc(raw, true);
+ raw = bpf_map_inc(raw, true);
break;
default:
WARN_ON_ONCE(1);
@@ -297,7 +297,8 @@ static void *bpf_obj_do_get(const struct filename *pathname,
goto out;
raw = bpf_any_get(inode->i_private, *type);
- touch_atime(&path);
+ if (!IS_ERR(raw))
+ touch_atime(&path);
path_put(&path);
return raw;
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 499d9e933f8e..f5a19548be12 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -66,7 +66,7 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
value_size < 8 || value_size % 8 ||
- value_size / 8 > PERF_MAX_STACK_DEPTH)
+ value_size / 8 > sysctl_perf_event_max_stack)
return ERR_PTR(-EINVAL);
/* hash table size must be power of 2 */
@@ -124,8 +124,8 @@ static u64 bpf_get_stackid(u64 r1, u64 r2, u64 flags, u64 r4, u64 r5)
struct perf_callchain_entry *trace;
struct stack_map_bucket *bucket, *new_bucket, *old_bucket;
u32 max_depth = map->value_size / 8;
- /* stack_map_alloc() checks that max_depth <= PERF_MAX_STACK_DEPTH */
- u32 init_nr = PERF_MAX_STACK_DEPTH - max_depth;
+ /* stack_map_alloc() checks that max_depth <= sysctl_perf_event_max_stack */
+ u32 init_nr = sysctl_perf_event_max_stack - max_depth;
u32 skip = flags & BPF_F_SKIP_FIELD_MASK;
u32 hash, id, trace_nr, trace_len;
bool user = flags & BPF_F_USER_STACK;
@@ -143,7 +143,7 @@ static u64 bpf_get_stackid(u64 r1, u64 r2, u64 flags, u64 r4, u64 r5)
return -EFAULT;
/* get_perf_callchain() guarantees that trace->nr >= init_nr
- * and trace-nr <= PERF_MAX_STACK_DEPTH, so trace_nr <= max_depth
+ * and trace-nr <= sysctl_perf_event_max_stack, so trace_nr <= max_depth
*/
trace_nr = trace->nr - init_nr;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index adc5e4bd74f8..cf5e9f7ad13a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -218,11 +218,18 @@ struct bpf_map *__bpf_map_get(struct fd f)
return f.file->private_data;
}
-void bpf_map_inc(struct bpf_map *map, bool uref)
+/* prog's and map's refcnt limit */
+#define BPF_MAX_REFCNT 32768
+
+struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
{
- atomic_inc(&map->refcnt);
+ if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
+ atomic_dec(&map->refcnt);
+ return ERR_PTR(-EBUSY);
+ }
if (uref)
atomic_inc(&map->usercnt);
+ return map;
}
struct bpf_map *bpf_map_get_with_uref(u32 ufd)
@@ -234,7 +241,7 @@ struct bpf_map *bpf_map_get_with_uref(u32 ufd)
if (IS_ERR(map))
return map;
- bpf_map_inc(map, true);
+ map = bpf_map_inc(map, true);
fdput(f);
return map;
@@ -658,6 +665,15 @@ static struct bpf_prog *__bpf_prog_get(struct fd f)
return f.file->private_data;
}
+struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
+{
+ if (atomic_inc_return(&prog->aux->refcnt) > BPF_MAX_REFCNT) {
+ atomic_dec(&prog->aux->refcnt);
+ return ERR_PTR(-EBUSY);
+ }
+ return prog;
+}
+
/* called by sockets/tracing/seccomp before attaching program to an event
* pairs with bpf_prog_put()
*/
@@ -670,7 +686,7 @@ struct bpf_prog *bpf_prog_get(u32 ufd)
if (IS_ERR(prog))
return prog;
- atomic_inc(&prog->aux->refcnt);
+ prog = bpf_prog_inc(prog);
fdput(f);
return prog;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index db2574e7b8b0..c5c17a62f509 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -239,16 +239,6 @@ static const char * const reg_type_str[] = {
[CONST_IMM] = "imm",
};
-static const struct {
- int map_type;
- int func_id;
-} func_limit[] = {
- {BPF_MAP_TYPE_PROG_ARRAY, BPF_FUNC_tail_call},
- {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_read},
- {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_output},
- {BPF_MAP_TYPE_STACK_TRACE, BPF_FUNC_get_stackid},
-};
-
static void print_verifier_state(struct verifier_env *env)
{
enum bpf_reg_type t;
@@ -921,27 +911,52 @@ static int check_func_arg(struct verifier_env *env, u32 regno,
static int check_map_func_compatibility(struct bpf_map *map, int func_id)
{
- bool bool_map, bool_func;
- int i;
-
if (!map)
return 0;
- for (i = 0; i < ARRAY_SIZE(func_limit); i++) {
- bool_map = (map->map_type == func_limit[i].map_type);
- bool_func = (func_id == func_limit[i].func_id);
- /* only when map & func pair match it can continue.
- * don't allow any other map type to be passed into
- * the special func;
- */
- if (bool_func && bool_map != bool_func) {
- verbose("cannot pass map_type %d into func %d\n",
- map->map_type, func_id);
- return -EINVAL;
- }
+ /* We need a two way check, first is from map perspective ... */
+ switch (map->map_type) {
+ case BPF_MAP_TYPE_PROG_ARRAY:
+ if (func_id != BPF_FUNC_tail_call)
+ goto error;
+ break;
+ case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
+ if (func_id != BPF_FUNC_perf_event_read &&
+ func_id != BPF_FUNC_perf_event_output)
+ goto error;
+ break;
+ case BPF_MAP_TYPE_STACK_TRACE:
+ if (func_id != BPF_FUNC_get_stackid)
+ goto error;
+ break;
+ default:
+ break;
+ }
+
+ /* ... and second from the function itself. */
+ switch (func_id) {
+ case BPF_FUNC_tail_call:
+ if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY)
+ goto error;
+ break;
+ case BPF_FUNC_perf_event_read:
+ case BPF_FUNC_perf_event_output:
+ if (map->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY)
+ goto error;
+ break;
+ case BPF_FUNC_get_stackid:
+ if (map->map_type != BPF_MAP_TYPE_STACK_TRACE)
+ goto error;
+ break;
+ default:
+ break;
}
return 0;
+error:
+ verbose("cannot pass map_type %d into func %d\n",
+ map->map_type, func_id);
+ return -EINVAL;
}
static int check_call(struct verifier_env *env, int func_id)
@@ -2049,15 +2064,18 @@ static int replace_map_fd_with_map_ptr(struct verifier_env *env)
return -E2BIG;
}
- /* remember this map */
- env->used_maps[env->used_map_cnt++] = map;
-
/* hold the map. If the program is rejected by verifier,
* the map will be released by release_maps() or it
* will be used by the valid program until it's unloaded
* and all maps are released in free_bpf_prog_info()
*/
- bpf_map_inc(map, false);
+ map = bpf_map_inc(map, false);
+ if (IS_ERR(map)) {
+ fdput(f);
+ return PTR_ERR(map);
+ }
+ env->used_maps[env->used_map_cnt++] = map;
+
fdput(f);
next_insn:
insn++;
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 909a7d31ffd3..86cb5c6e8932 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1215,6 +1215,41 @@ static void cgroup_destroy_root(struct cgroup_root *root)
cgroup_free_root(root);
}
+/*
+ * look up cgroup associated with current task's cgroup namespace on the
+ * specified hierarchy
+ */
+static struct cgroup *
+current_cgns_cgroup_from_root(struct cgroup_root *root)
+{
+ struct cgroup *res = NULL;
+ struct css_set *cset;
+
+ lockdep_assert_held(&css_set_lock);
+
+ rcu_read_lock();
+
+ cset = current->nsproxy->cgroup_ns->root_cset;
+ if (cset == &init_css_set) {
+ res = &root->cgrp;
+ } else {
+ struct cgrp_cset_link *link;
+
+ list_for_each_entry(link, &cset->cgrp_links, cgrp_link) {
+ struct cgroup *c = link->cgrp;
+
+ if (c->root == root) {
+ res = c;
+ break;
+ }
+ }
+ }
+ rcu_read_unlock();
+
+ BUG_ON(!res);
+ return res;
+}
+
/* look up cgroup associated with given css_set on the specified hierarchy */
static struct cgroup *cset_cgroup_from_root(struct css_set *cset,
struct cgroup_root *root)
@@ -1593,6 +1628,33 @@ static int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask)
return 0;
}
+static int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node,
+ struct kernfs_root *kf_root)
+{
+ int len = 0;
+ char *buf = NULL;
+ struct cgroup_root *kf_cgroot = cgroup_root_from_kf(kf_root);
+ struct cgroup *ns_cgroup;
+
+ buf = kmalloc(PATH_MAX, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ spin_lock_bh(&css_set_lock);
+ ns_cgroup = current_cgns_cgroup_from_root(kf_cgroot);
+ len = kernfs_path_from_node(kf_node, ns_cgroup->kn, buf, PATH_MAX);
+ spin_unlock_bh(&css_set_lock);
+
+ if (len >= PATH_MAX)
+ len = -ERANGE;
+ else if (len > 0) {
+ seq_escape(sf, buf, " \t\n\\");
+ len = 0;
+ }
+ kfree(buf);
+ return len;
+}
+
static int cgroup_show_options(struct seq_file *seq,
struct kernfs_root *kf_root)
{
@@ -5433,6 +5495,7 @@ static struct kernfs_syscall_ops cgroup_kf_syscall_ops = {
.mkdir = cgroup_mkdir,
.rmdir = cgroup_rmdir,
.rename = cgroup_rename,
+ .show_path = cgroup_show_path,
};
static void __init cgroup_init_subsys(struct cgroup_subsys *ss, bool early)
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 3e3f6e49eabb..d948e44c471e 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -703,21 +703,6 @@ static int takedown_cpu(unsigned int cpu)
struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
int err;
- /*
- * By now we've cleared cpu_active_mask, wait for all preempt-disabled
- * and RCU users of this state to go away such that all new such users
- * will observe it.
- *
- * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might
- * not imply sync_sched(), so wait for both.
- *
- * Do sync before park smpboot threads to take care the rcu boost case.
- */
- if (IS_ENABLED(CONFIG_PREEMPT))
- synchronize_rcu_mult(call_rcu, call_rcu_sched);
- else
- synchronize_rcu();
-
/* Park the smpboot threads */
kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread);
smpboot_park_threads(cpu);
@@ -923,8 +908,6 @@ void cpuhp_online_idle(enum cpuhp_state state)
st->state = CPUHP_AP_ONLINE_IDLE;
- /* The cpu is marked online, set it active now */
- set_cpu_active(cpu, true);
/* Unpark the stopper thread and the hotplug thread of this cpu */
stop_machine_unpark(cpu);
kthread_unpark(st->thread);
@@ -1236,6 +1219,12 @@ static struct cpuhp_step cpuhp_ap_states[] = {
.name = "ap:offline",
.cant_stop = true,
},
+ /* First state is scheduler control. Interrupts are disabled */
+ [CPUHP_AP_SCHED_STARTING] = {
+ .name = "sched:starting",
+ .startup = sched_cpu_starting,
+ .teardown = sched_cpu_dying,
+ },
/*
* Low level startup/teardown notifiers. Run with interrupts
* disabled. Will be removed once the notifiers are converted to
@@ -1274,6 +1263,15 @@ static struct cpuhp_step cpuhp_ap_states[] = {
* The dynamically registered state space is here
*/
+#ifdef CONFIG_SMP
+ /* Last state is scheduler control setting the cpu active */
+ [CPUHP_AP_ACTIVE] = {
+ .name = "sched:active",
+ .startup = sched_cpu_activate,
+ .teardown = sched_cpu_deactivate,
+ },
+#endif
+
/* CPU is fully up and running. */
[CPUHP_ONLINE] = {
.name = "online",
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index 343c22f5e867..b9325e7dcba1 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -18,6 +18,14 @@ struct callchain_cpus_entries {
struct perf_callchain_entry *cpu_entries[0];
};
+int sysctl_perf_event_max_stack __read_mostly = PERF_MAX_STACK_DEPTH;
+
+static inline size_t perf_callchain_entry__sizeof(void)
+{
+ return (sizeof(struct perf_callchain_entry) +
+ sizeof(__u64) * sysctl_perf_event_max_stack);
+}
+
static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]);
static atomic_t nr_callchain_events;
static DEFINE_MUTEX(callchain_mutex);
@@ -73,7 +81,7 @@ static int alloc_callchain_buffers(void)
if (!entries)
return -ENOMEM;
- size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS;
+ size = perf_callchain_entry__sizeof() * PERF_NR_CONTEXTS;
for_each_possible_cpu(cpu) {
entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL,
@@ -147,7 +155,8 @@ static struct perf_callchain_entry *get_callchain_entry(int *rctx)
cpu = smp_processor_id();
- return &entries->cpu_entries[cpu][*rctx];
+ return (((void *)entries->cpu_entries[cpu]) +
+ (*rctx * perf_callchain_entry__sizeof()));
}
static void
@@ -215,3 +224,25 @@ exit_put:
return entry;
}
+
+int perf_event_max_stack_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ int new_value = sysctl_perf_event_max_stack, ret;
+ struct ctl_table new_table = *table;
+
+ new_table.data = &new_value;
+ ret = proc_dointvec_minmax(&new_table, write, buffer, lenp, ppos);
+ if (ret || !write)
+ return ret;
+
+ mutex_lock(&callchain_mutex);
+ if (atomic_read(&nr_callchain_events))
+ ret = -EBUSY;
+ else
+ sysctl_perf_event_max_stack = new_value;
+
+ mutex_unlock(&callchain_mutex);
+
+ return ret;
+}
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 52bedc5a5aaa..050a290c72c7 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -44,6 +44,8 @@
#include <linux/compat.h>
#include <linux/bpf.h>
#include <linux/filter.h>
+#include <linux/namei.h>
+#include <linux/parser.h>
#include "internal.h"
@@ -351,7 +353,7 @@ static struct srcu_struct pmus_srcu;
* 1 - disallow cpu events for unpriv
* 2 - disallow kernel profiling for unpriv
*/
-int sysctl_perf_event_paranoid __read_mostly = 1;
+int sysctl_perf_event_paranoid __read_mostly = 2;
/* Minimum for 512 kiB + 1 user control page */
int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */
@@ -412,7 +414,8 @@ int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
if (ret || !write)
return ret;
- if (sysctl_perf_cpu_time_max_percent == 100) {
+ if (sysctl_perf_cpu_time_max_percent == 100 ||
+ sysctl_perf_cpu_time_max_percent == 0) {
printk(KERN_WARNING
"perf: Dynamic interrupt throttling disabled, can hang your system!\n");
WRITE_ONCE(perf_sample_allowed_ns, 0);
@@ -1105,6 +1108,7 @@ static void put_ctx(struct perf_event_context *ctx)
* function.
*
* Lock order:
+ * cred_guard_mutex
* task_struct::perf_event_mutex
* perf_event_context::mutex
* perf_event::child_mutex;
@@ -1925,8 +1929,13 @@ event_sched_in(struct perf_event *event,
if (event->state <= PERF_EVENT_STATE_OFF)
return 0;
- event->state = PERF_EVENT_STATE_ACTIVE;
- event->oncpu = smp_processor_id();
+ WRITE_ONCE(event->oncpu, smp_processor_id());
+ /*
+ * Order event::oncpu write to happen before the ACTIVE state
+ * is visible.
+ */
+ smp_wmb();
+ WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE);
/*
* Unthrottle events, since we scheduled we might have missed several
@@ -2358,6 +2367,112 @@ void perf_event_enable(struct perf_event *event)
}
EXPORT_SYMBOL_GPL(perf_event_enable);
+struct stop_event_data {
+ struct perf_event *event;
+ unsigned int restart;
+};
+
+static int __perf_event_stop(void *info)
+{
+ struct stop_event_data *sd = info;
+ struct perf_event *event = sd->event;
+
+ /* if it's already INACTIVE, do nothing */
+ if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE)
+ return 0;
+
+ /* matches smp_wmb() in event_sched_in() */
+ smp_rmb();
+
+ /*
+ * There is a window with interrupts enabled before we get here,
+ * so we need to check again lest we try to stop another CPU's event.
+ */
+ if (READ_ONCE(event->oncpu) != smp_processor_id())
+ return -EAGAIN;
+
+ event->pmu->stop(event, PERF_EF_UPDATE);
+
+ /*
+ * May race with the actual stop (through perf_pmu_output_stop()),
+ * but it is only used for events with AUX ring buffer, and such
+ * events will refuse to restart because of rb::aux_mmap_count==0,
+ * see comments in perf_aux_output_begin().
+ *
+ * Since this is happening on a event-local CPU, no trace is lost
+ * while restarting.
+ */
+ if (sd->restart)
+ event->pmu->start(event, PERF_EF_START);
+
+ return 0;
+}
+
+static int perf_event_restart(struct perf_event *event)
+{
+ struct stop_event_data sd = {
+ .event = event,
+ .restart = 1,
+ };
+ int ret = 0;
+
+ do {
+ if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE)
+ return 0;
+
+ /* matches smp_wmb() in event_sched_in() */
+ smp_rmb();
+
+ /*
+ * We only want to restart ACTIVE events, so if the event goes
+ * inactive here (event->oncpu==-1), there's nothing more to do;
+ * fall through with ret==-ENXIO.
+ */
+ ret = cpu_function_call(READ_ONCE(event->oncpu),
+ __perf_event_stop, &sd);
+ } while (ret == -EAGAIN);
+
+ return ret;
+}
+
+/*
+ * In order to contain the amount of racy and tricky in the address filter
+ * configuration management, it is a two part process:
+ *
+ * (p1) when userspace mappings change as a result of (1) or (2) or (3) below,
+ * we update the addresses of corresponding vmas in
+ * event::addr_filters_offs array and bump the event::addr_filters_gen;
+ * (p2) when an event is scheduled in (pmu::add), it calls
+ * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync()
+ * if the generation has changed since the previous call.
+ *
+ * If (p1) happens while the event is active, we restart it to force (p2).
+ *
+ * (1) perf_addr_filters_apply(): adjusting filters' offsets based on
+ * pre-existing mappings, called once when new filters arrive via SET_FILTER
+ * ioctl;
+ * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly
+ * registered mapping, called for every new mmap(), with mm::mmap_sem down
+ * for reading;
+ * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process
+ * of exec.
+ */
+void perf_event_addr_filters_sync(struct perf_event *event)
+{
+ struct perf_addr_filters_head *ifh = perf_event_addr_filters(event);
+
+ if (!has_addr_filter(event))
+ return;
+
+ raw_spin_lock(&ifh->lock);
+ if (event->addr_filters_gen != event->hw.addr_filters_gen) {
+ event->pmu->addr_filters_sync(event);
+ event->hw.addr_filters_gen = event->addr_filters_gen;
+ }
+ raw_spin_unlock(&ifh->lock);
+}
+EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync);
+
static int _perf_event_refresh(struct perf_event *event, int refresh)
{
/*
@@ -3207,16 +3322,6 @@ out:
put_ctx(clone_ctx);
}
-void perf_event_exec(void)
-{
- int ctxn;
-
- rcu_read_lock();
- for_each_task_context_nr(ctxn)
- perf_event_enable_on_exec(ctxn);
- rcu_read_unlock();
-}
-
struct perf_read_data {
struct perf_event *event;
bool group;
@@ -3420,7 +3525,6 @@ static struct task_struct *
find_lively_task_by_vpid(pid_t vpid)
{
struct task_struct *task;
- int err;
rcu_read_lock();
if (!vpid)
@@ -3434,16 +3538,7 @@ find_lively_task_by_vpid(pid_t vpid)
if (!task)
return ERR_PTR(-ESRCH);
- /* Reuse ptrace permission checks for now. */
- err = -EACCES;
- if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS))
- goto errout;
-
return task;
-errout:
- put_task_struct(task);
- return ERR_PTR(err);
-
}
/*
@@ -3728,6 +3823,9 @@ static bool exclusive_event_installable(struct perf_event *event,
return true;
}
+static void perf_addr_filters_splice(struct perf_event *event,
+ struct list_head *head);
+
static void _free_event(struct perf_event *event)
{
irq_work_sync(&event->pending);
@@ -3755,6 +3853,8 @@ static void _free_event(struct perf_event *event)
}
perf_event_free_bpf_prog(event);
+ perf_addr_filters_splice(event, NULL);
+ kfree(event->addr_filters_offs);
if (event->destroy)
event->destroy(event);
@@ -4351,6 +4451,19 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon
case PERF_EVENT_IOC_SET_BPF:
return perf_event_set_bpf_prog(event, arg);
+ case PERF_EVENT_IOC_PAUSE_OUTPUT: {
+ struct ring_buffer *rb;
+
+ rcu_read_lock();
+ rb = rcu_dereference(event->rb);
+ if (!rb || !rb->nr_pages) {
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+ rb_toggle_paused(rb, !!arg);
+ rcu_read_unlock();
+ return 0;
+ }
default:
return -ENOTTY;
}
@@ -4667,6 +4780,8 @@ static void perf_mmap_open(struct vm_area_struct *vma)
event->pmu->event_mapped(event);
}
+static void perf_pmu_output_stop(struct perf_event *event);
+
/*
* A buffer can be mmap()ed multiple times; either directly through the same
* event, or through other events by use of perf_event_set_output().
@@ -4694,10 +4809,22 @@ static void perf_mmap_close(struct vm_area_struct *vma)
*/
if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff &&
atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) {
+ /*
+ * Stop all AUX events that are writing to this buffer,
+ * so that we can free its AUX pages and corresponding PMU
+ * data. Note that after rb::aux_mmap_count dropped to zero,
+ * they won't start any more (see perf_aux_output_begin()).
+ */
+ perf_pmu_output_stop(event);
+
+ /* now it's safe to free the pages */
atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm);
vma->vm_mm->pinned_vm -= rb->aux_mmap_locked;
+ /* this has to be the last one */
rb_free_aux(rb);
+ WARN_ON_ONCE(atomic_read(&rb->aux_refcount));
+
mutex_unlock(&event->mmap_mutex);
}
@@ -5638,9 +5765,13 @@ void perf_prepare_sample(struct perf_event_header *header,
}
}
-void perf_event_output(struct perf_event *event,
- struct perf_sample_data *data,
- struct pt_regs *regs)
+static void __always_inline
+__perf_event_output(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs,
+ int (*output_begin)(struct perf_output_handle *,
+ struct perf_event *,
+ unsigned int))
{
struct perf_output_handle handle;
struct perf_event_header header;
@@ -5650,7 +5781,7 @@ void perf_event_output(struct perf_event *event,
perf_prepare_sample(&header, data, event, regs);
- if (perf_output_begin(&handle, event, header.size))
+ if (output_begin(&handle, event, header.size))
goto exit;
perf_output_sample(&handle, &header, data, event);
@@ -5661,6 +5792,30 @@ exit:
rcu_read_unlock();
}
+void
+perf_event_output_forward(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ __perf_event_output(event, data, regs, perf_output_begin_forward);
+}
+
+void
+perf_event_output_backward(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ __perf_event_output(event, data, regs, perf_output_begin_backward);
+}
+
+void
+perf_event_output(struct perf_event *event,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ __perf_event_output(event, data, regs, perf_output_begin);
+}
+
/*
* read event_id
*/
@@ -5706,15 +5861,18 @@ typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);
static void
perf_event_aux_ctx(struct perf_event_context *ctx,
perf_event_aux_output_cb output,
- void *data)
+ void *data, bool all)
{
struct perf_event *event;
list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
- if (event->state < PERF_EVENT_STATE_INACTIVE)
- continue;
- if (!event_filter_match(event))
- continue;
+ if (!all) {
+ if (event->state < PERF_EVENT_STATE_INACTIVE)
+ continue;
+ if (!event_filter_match(event))
+ continue;
+ }
+
output(event, data);
}
}
@@ -5725,7 +5883,7 @@ perf_event_aux_task_ctx(perf_event_aux_output_cb output, void *data,
{
rcu_read_lock();
preempt_disable();
- perf_event_aux_ctx(task_ctx, output, data);
+ perf_event_aux_ctx(task_ctx, output, data, false);
preempt_enable();
rcu_read_unlock();
}
@@ -5755,13 +5913,13 @@ perf_event_aux(perf_event_aux_output_cb output, void *data,
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
if (cpuctx->unique_pmu != pmu)
goto next;
- perf_event_aux_ctx(&cpuctx->ctx, output, data);
+ perf_event_aux_ctx(&cpuctx->ctx, output, data, false);
ctxn = pmu->task_ctx_nr;
if (ctxn < 0)
goto next;
ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
if (ctx)
- perf_event_aux_ctx(ctx, output, data);
+ perf_event_aux_ctx(ctx, output, data, false);
next:
put_cpu_ptr(pmu->pmu_cpu_context);
}
@@ -5769,6 +5927,134 @@ next:
}
/*
+ * Clear all file-based filters at exec, they'll have to be
+ * re-instated when/if these objects are mmapped again.
+ */
+static void perf_event_addr_filters_exec(struct perf_event *event, void *data)
+{
+ struct perf_addr_filters_head *ifh = perf_event_addr_filters(event);
+ struct perf_addr_filter *filter;
+ unsigned int restart = 0, count = 0;
+ unsigned long flags;
+
+ if (!has_addr_filter(event))
+ return;
+
+ raw_spin_lock_irqsave(&ifh->lock, flags);
+ list_for_each_entry(filter, &ifh->list, entry) {
+ if (filter->inode) {
+ event->addr_filters_offs[count] = 0;
+ restart++;
+ }
+
+ count++;
+ }
+
+ if (restart)
+ event->addr_filters_gen++;
+ raw_spin_unlock_irqrestore(&ifh->lock, flags);
+
+ if (restart)
+ perf_event_restart(event);
+}
+
+void perf_event_exec(void)
+{
+ struct perf_event_context *ctx;
+ int ctxn;
+
+ rcu_read_lock();
+ for_each_task_context_nr(ctxn) {
+ ctx = current->perf_event_ctxp[ctxn];
+ if (!ctx)
+ continue;
+
+ perf_event_enable_on_exec(ctxn);
+
+ perf_event_aux_ctx(ctx, perf_event_addr_filters_exec, NULL,
+ true);
+ }
+ rcu_read_unlock();
+}
+
+struct remote_output {
+ struct ring_buffer *rb;
+ int err;
+};
+
+static void __perf_event_output_stop(struct perf_event *event, void *data)
+{
+ struct perf_event *parent = event->parent;
+ struct remote_output *ro = data;
+ struct ring_buffer *rb = ro->rb;
+ struct stop_event_data sd = {
+ .event = event,
+ };
+
+ if (!has_aux(event))
+ return;
+
+ if (!parent)
+ parent = event;
+
+ /*
+ * In case of inheritance, it will be the parent that links to the
+ * ring-buffer, but it will be the child that's actually using it:
+ */
+ if (rcu_dereference(parent->rb) == rb)
+ ro->err = __perf_event_stop(&sd);
+}
+
+static int __perf_pmu_output_stop(void *info)
+{
+ struct perf_event *event = info;
+ struct pmu *pmu = event->pmu;
+ struct perf_cpu_context *cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
+ struct remote_output ro = {
+ .rb = event->rb,
+ };
+
+ rcu_read_lock();
+ perf_event_aux_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false);
+ if (cpuctx->task_ctx)
+ perf_event_aux_ctx(cpuctx->task_ctx, __perf_event_output_stop,
+ &ro, false);
+ rcu_read_unlock();
+
+ return ro.err;
+}
+
+static void perf_pmu_output_stop(struct perf_event *event)
+{
+ struct perf_event *iter;
+ int err, cpu;
+
+restart:
+ rcu_read_lock();
+ list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) {
+ /*
+ * For per-CPU events, we need to make sure that neither they
+ * nor their children are running; for cpu==-1 events it's
+ * sufficient to stop the event itself if it's active, since
+ * it can't have children.
+ */
+ cpu = iter->cpu;
+ if (cpu == -1)
+ cpu = READ_ONCE(iter->oncpu);
+
+ if (cpu == -1)
+ continue;
+
+ err = cpu_function_call(cpu, __perf_pmu_output_stop, event);
+ if (err == -EAGAIN) {
+ rcu_read_unlock();
+ goto restart;
+ }
+ }
+ rcu_read_unlock();
+}
+
+/*
* task tracking -- fork/exit
*
* enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task
@@ -6177,6 +6463,87 @@ got_name:
kfree(buf);
}
+/*
+ * Whether this @filter depends on a dynamic object which is not loaded
+ * yet or its load addresses are not known.
+ */
+static bool perf_addr_filter_needs_mmap(struct perf_addr_filter *filter)
+{
+ return filter->filter && filter->inode;
+}
+
+/*
+ * Check whether inode and address range match filter criteria.
+ */
+static bool perf_addr_filter_match(struct perf_addr_filter *filter,
+ struct file *file, unsigned long offset,
+ unsigned long size)
+{
+ if (filter->inode != file->f_inode)
+ return false;
+
+ if (filter->offset > offset + size)
+ return false;
+
+ if (filter->offset + filter->size < offset)
+ return false;
+
+ return true;
+}
+
+static void __perf_addr_filters_adjust(struct perf_event *event, void *data)
+{
+ struct perf_addr_filters_head *ifh = perf_event_addr_filters(event);
+ struct vm_area_struct *vma = data;
+ unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags;
+ struct file *file = vma->vm_file;
+ struct perf_addr_filter *filter;
+ unsigned int restart = 0, count = 0;
+
+ if (!has_addr_filter(event))
+ return;
+
+ if (!file)
+ return;
+
+ raw_spin_lock_irqsave(&ifh->lock, flags);
+ list_for_each_entry(filter, &ifh->list, entry) {
+ if (perf_addr_filter_match(filter, file, off,
+ vma->vm_end - vma->vm_start)) {
+ event->addr_filters_offs[count] = vma->vm_start;
+ restart++;
+ }
+
+ count++;
+ }
+
+ if (restart)
+ event->addr_filters_gen++;
+ raw_spin_unlock_irqrestore(&ifh->lock, flags);
+
+ if (restart)
+ perf_event_restart(event);
+}
+
+/*
+ * Adjust all task's events' filters to the new vma
+ */
+static void perf_addr_filters_adjust(struct vm_area_struct *vma)
+{
+ struct perf_event_context *ctx;
+ int ctxn;
+
+ rcu_read_lock();
+ for_each_task_context_nr(ctxn) {
+ ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
+ if (!ctx)
+ continue;
+
+ perf_event_aux_ctx(ctx, __perf_addr_filters_adjust, vma, true);
+ }
+ rcu_read_unlock();
+}
+
void perf_event_mmap(struct vm_area_struct *vma)
{
struct perf_mmap_event mmap_event;
@@ -6208,6 +6575,7 @@ void perf_event_mmap(struct vm_area_struct *vma)
/* .flags (attr_mmap2 only) */
};
+ perf_addr_filters_adjust(vma);
perf_event_mmap_event(&mmap_event);
}
@@ -6499,10 +6867,7 @@ static int __perf_event_overflow(struct perf_event *event,
irq_work_queue(&event->pending);
}
- if (event->overflow_handler)
- event->overflow_handler(event, data, regs);
- else
- perf_event_output(event, data, regs);
+ event->overflow_handler(event, data, regs);
if (*perf_event_fasync(event) && event->pending_kill) {
event->pending_wakeup = 1;
@@ -7089,24 +7454,6 @@ static inline void perf_tp_register(void)
perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT);
}
-static int perf_event_set_filter(struct perf_event *event, void __user *arg)
-{
- char *filter_str;
- int ret;
-
- if (event->attr.type != PERF_TYPE_TRACEPOINT)
- return -EINVAL;
-
- filter_str = strndup_user(arg, PAGE_SIZE);
- if (IS_ERR(filter_str))
- return PTR_ERR(filter_str);
-
- ret = ftrace_profile_set_filter(event, event->attr.config, filter_str);
-
- kfree(filter_str);
- return ret;
-}
-
static void perf_event_free_filter(struct perf_event *event)
{
ftrace_profile_free_filter(event);
@@ -7161,11 +7508,6 @@ static inline void perf_tp_register(void)
{
}
-static int perf_event_set_filter(struct perf_event *event, void __user *arg)
-{
- return -ENOENT;
-}
-
static void perf_event_free_filter(struct perf_event *event)
{
}
@@ -7194,6 +7536,387 @@ void perf_bp_event(struct perf_event *bp, void *data)
#endif
/*
+ * Allocate a new address filter
+ */
+static struct perf_addr_filter *
+perf_addr_filter_new(struct perf_event *event, struct list_head *filters)
+{
+ int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu);
+ struct perf_addr_filter *filter;
+
+ filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node);
+ if (!filter)
+ return NULL;
+
+ INIT_LIST_HEAD(&filter->entry);
+ list_add_tail(&filter->entry, filters);
+
+ return filter;
+}
+
+static void free_filters_list(struct list_head *filters)
+{
+ struct perf_addr_filter *filter, *iter;
+
+ list_for_each_entry_safe(filter, iter, filters, entry) {
+ if (filter->inode)
+ iput(filter->inode);
+ list_del(&filter->entry);
+ kfree(filter);
+ }
+}
+
+/*
+ * Free existing address filters and optionally install new ones
+ */
+static void perf_addr_filters_splice(struct perf_event *event,
+ struct list_head *head)
+{
+ unsigned long flags;
+ LIST_HEAD(list);
+
+ if (!has_addr_filter(event))
+ return;
+
+ /* don't bother with children, they don't have their own filters */
+ if (event->parent)
+ return;
+
+ raw_spin_lock_irqsave(&event->addr_filters.lock, flags);
+
+ list_splice_init(&event->addr_filters.list, &list);
+ if (head)
+ list_splice(head, &event->addr_filters.list);
+
+ raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags);
+
+ free_filters_list(&list);
+}
+
+/*
+ * Scan through mm's vmas and see if one of them matches the
+ * @filter; if so, adjust filter's address range.
+ * Called with mm::mmap_sem down for reading.
+ */
+static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter,
+ struct mm_struct *mm)
+{
+ struct vm_area_struct *vma;
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ struct file *file = vma->vm_file;
+ unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
+ unsigned long vma_size = vma->vm_end - vma->vm_start;
+
+ if (!file)
+ continue;
+
+ if (!perf_addr_filter_match(filter, file, off, vma_size))
+ continue;
+
+ return vma->vm_start;
+ }
+
+ return 0;
+}
+
+/*
+ * Update event's address range filters based on the
+ * task's existing mappings, if any.
+ */
+static void perf_event_addr_filters_apply(struct perf_event *event)
+{
+ struct perf_addr_filters_head *ifh = perf_event_addr_filters(event);
+ struct task_struct *task = READ_ONCE(event->ctx->task);
+ struct perf_addr_filter *filter;
+ struct mm_struct *mm = NULL;
+ unsigned int count = 0;
+ unsigned long flags;
+
+ /*
+ * We may observe TASK_TOMBSTONE, which means that the event tear-down
+ * will stop on the parent's child_mutex that our caller is also holding
+ */
+ if (task == TASK_TOMBSTONE)
+ return;
+
+ mm = get_task_mm(event->ctx->task);
+ if (!mm)
+ goto restart;
+
+ down_read(&mm->mmap_sem);
+
+ raw_spin_lock_irqsave(&ifh->lock, flags);
+ list_for_each_entry(filter, &ifh->list, entry) {
+ event->addr_filters_offs[count] = 0;
+
+ if (perf_addr_filter_needs_mmap(filter))
+ event->addr_filters_offs[count] =
+ perf_addr_filter_apply(filter, mm);
+
+ count++;
+ }
+
+ event->addr_filters_gen++;
+ raw_spin_unlock_irqrestore(&ifh->lock, flags);
+
+ up_read(&mm->mmap_sem);
+
+ mmput(mm);
+
+restart:
+ perf_event_restart(event);
+}
+
+/*
+ * Address range filtering: limiting the data to certain
+ * instruction address ranges. Filters are ioctl()ed to us from
+ * userspace as ascii strings.
+ *
+ * Filter string format:
+ *
+ * ACTION RANGE_SPEC
+ * where ACTION is one of the
+ * * "filter": limit the trace to this region
+ * * "start": start tracing from this address
+ * * "stop": stop tracing at this address/region;
+ * RANGE_SPEC is
+ * * for kernel addresses: <start address>[/<size>]
+ * * for object files: <start address>[/<size>]@</path/to/object/file>
+ *
+ * if <size> is not specified, the range is treated as a single address.
+ */
+enum {
+ IF_ACT_FILTER,
+ IF_ACT_START,
+ IF_ACT_STOP,
+ IF_SRC_FILE,
+ IF_SRC_KERNEL,
+ IF_SRC_FILEADDR,
+ IF_SRC_KERNELADDR,
+};
+
+enum {
+ IF_STATE_ACTION = 0,
+ IF_STATE_SOURCE,
+ IF_STATE_END,
+};
+
+static const match_table_t if_tokens = {
+ { IF_ACT_FILTER, "filter" },
+ { IF_ACT_START, "start" },
+ { IF_ACT_STOP, "stop" },
+ { IF_SRC_FILE, "%u/%u@%s" },
+ { IF_SRC_KERNEL, "%u/%u" },
+ { IF_SRC_FILEADDR, "%u@%s" },
+ { IF_SRC_KERNELADDR, "%u" },
+};
+
+/*
+ * Address filter string parser
+ */
+static int
+perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
+ struct list_head *filters)
+{
+ struct perf_addr_filter *filter = NULL;
+ char *start, *orig, *filename = NULL;
+ struct path path;
+ substring_t args[MAX_OPT_ARGS];
+ int state = IF_STATE_ACTION, token;
+ unsigned int kernel = 0;
+ int ret = -EINVAL;
+
+ orig = fstr = kstrdup(fstr, GFP_KERNEL);
+ if (!fstr)
+ return -ENOMEM;
+
+ while ((start = strsep(&fstr, " ,\n")) != NULL) {
+ ret = -EINVAL;
+
+ if (!*start)
+ continue;
+
+ /* filter definition begins */
+ if (state == IF_STATE_ACTION) {
+ filter = perf_addr_filter_new(event, filters);
+ if (!filter)
+ goto fail;
+ }
+
+ token = match_token(start, if_tokens, args);
+ switch (token) {
+ case IF_ACT_FILTER:
+ case IF_ACT_START:
+ filter->filter = 1;
+
+ case IF_ACT_STOP:
+ if (state != IF_STATE_ACTION)
+ goto fail;
+
+ state = IF_STATE_SOURCE;
+ break;
+
+ case IF_SRC_KERNELADDR:
+ case IF_SRC_KERNEL:
+ kernel = 1;
+
+ case IF_SRC_FILEADDR:
+ case IF_SRC_FILE:
+ if (state != IF_STATE_SOURCE)
+ goto fail;
+
+ if (token == IF_SRC_FILE || token == IF_SRC_KERNEL)
+ filter->range = 1;
+
+ *args[0].to = 0;
+ ret = kstrtoul(args[0].from, 0, &filter->offset);
+ if (ret)
+ goto fail;
+
+ if (filter->range) {
+ *args[1].to = 0;
+ ret = kstrtoul(args[1].from, 0, &filter->size);
+ if (ret)
+ goto fail;
+ }
+
+ if (token == IF_SRC_FILE) {
+ filename = match_strdup(&args[2]);
+ if (!filename) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ state = IF_STATE_END;
+ break;
+
+ default:
+ goto fail;
+ }
+
+ /*
+ * Filter definition is fully parsed, validate and install it.
+ * Make sure that it doesn't contradict itself or the event's
+ * attribute.
+ */
+ if (state == IF_STATE_END) {
+ if (kernel && event->attr.exclude_kernel)
+ goto fail;
+
+ if (!kernel) {
+ if (!filename)
+ goto fail;
+
+ /* look up the path and grab its inode */
+ ret = kern_path(filename, LOOKUP_FOLLOW, &path);
+ if (ret)
+ goto fail_free_name;
+
+ filter->inode = igrab(d_inode(path.dentry));
+ path_put(&path);
+ kfree(filename);
+ filename = NULL;
+
+ ret = -EINVAL;
+ if (!filter->inode ||
+ !S_ISREG(filter->inode->i_mode))
+ /* free_filters_list() will iput() */
+ goto fail;
+ }
+
+ /* ready to consume more filters */
+ state = IF_STATE_ACTION;
+ filter = NULL;
+ }
+ }
+
+ if (state != IF_STATE_ACTION)
+ goto fail;
+
+ kfree(orig);
+
+ return 0;
+
+fail_free_name:
+ kfree(filename);
+fail:
+ free_filters_list(filters);
+ kfree(orig);
+
+ return ret;
+}
+
+static int
+perf_event_set_addr_filter(struct perf_event *event, char *filter_str)
+{
+ LIST_HEAD(filters);
+ int ret;
+
+ /*
+ * Since this is called in perf_ioctl() path, we're already holding
+ * ctx::mutex.
+ */
+ lockdep_assert_held(&event->ctx->mutex);
+
+ if (WARN_ON_ONCE(event->parent))
+ return -EINVAL;
+
+ /*
+ * For now, we only support filtering in per-task events; doing so
+ * for CPU-wide events requires additional context switching trickery,
+ * since same object code will be mapped at different virtual
+ * addresses in different processes.
+ */
+ if (!event->ctx->task)
+ return -EOPNOTSUPP;
+
+ ret = perf_event_parse_addr_filter(event, filter_str, &filters);
+ if (ret)
+ return ret;
+
+ ret = event->pmu->addr_filters_validate(&filters);
+ if (ret) {
+ free_filters_list(&filters);
+ return ret;
+ }
+
+ /* remove existing filters, if any */
+ perf_addr_filters_splice(event, &filters);
+
+ /* install new filters */
+ perf_event_for_each_child(event, perf_event_addr_filters_apply);
+
+ return ret;
+}
+
+static int perf_event_set_filter(struct perf_event *event, void __user *arg)
+{
+ char *filter_str;
+ int ret = -EINVAL;
+
+ if ((event->attr.type != PERF_TYPE_TRACEPOINT ||
+ !IS_ENABLED(CONFIG_EVENT_TRACING)) &&
+ !has_addr_filter(event))
+ return -EINVAL;
+
+ filter_str = strndup_user(arg, PAGE_SIZE);
+ if (IS_ERR(filter_str))
+ return PTR_ERR(filter_str);
+
+ if (IS_ENABLED(CONFIG_EVENT_TRACING) &&
+ event->attr.type == PERF_TYPE_TRACEPOINT)
+ ret = ftrace_profile_set_filter(event, event->attr.config,
+ filter_str);
+ else if (has_addr_filter(event))
+ ret = perf_event_set_addr_filter(event, filter_str);
+
+ kfree(filter_str);
+ return ret;
+}
+
+/*
* hrtimer based swevent callback
*/
@@ -7550,6 +8273,20 @@ static void free_pmu_context(struct pmu *pmu)
out:
mutex_unlock(&pmus_lock);
}
+
+/*
+ * Let userspace know that this PMU supports address range filtering:
+ */
+static ssize_t nr_addr_filters_show(struct device *dev,
+ struct device_attribute *attr,
+ char *page)
+{
+ struct pmu *pmu = dev_get_drvdata(dev);
+
+ return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters);
+}
+DEVICE_ATTR_RO(nr_addr_filters);
+
static struct idr pmu_idr;
static ssize_t
@@ -7651,9 +8388,19 @@ static int pmu_dev_alloc(struct pmu *pmu)
if (ret)
goto free_dev;
+ /* For PMUs with address filters, throw in an extra attribute: */
+ if (pmu->nr_addr_filters)
+ ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters);
+
+ if (ret)
+ goto del_dev;
+
out:
return ret;
+del_dev:
+ device_del(pmu->dev);
+
free_dev:
put_device(pmu->dev);
goto out;
@@ -7693,6 +8440,21 @@ int perf_pmu_register(struct pmu *pmu, const char *name, int type)
}
skip_type:
+ if (pmu->task_ctx_nr == perf_hw_context) {
+ static int hw_context_taken = 0;
+
+ /*
+ * Other than systems with heterogeneous CPUs, it never makes
+ * sense for two PMUs to share perf_hw_context. PMUs which are
+ * uncore must use perf_invalid_context.
+ */
+ if (WARN_ON_ONCE(hw_context_taken &&
+ !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS)))
+ pmu->task_ctx_nr = perf_invalid_context;
+
+ hw_context_taken = 1;
+ }
+
pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr);
if (pmu->pmu_cpu_context)
goto got_cpu_context;
@@ -7780,6 +8542,8 @@ void perf_pmu_unregister(struct pmu *pmu)
free_percpu(pmu->pmu_disable_count);
if (pmu->type >= PERF_TYPE_MAX)
idr_remove(&pmu_idr, pmu->type);
+ if (pmu->nr_addr_filters)
+ device_remove_file(pmu->dev, &dev_attr_nr_addr_filters);
device_del(pmu->dev);
put_device(pmu->dev);
free_pmu_context(pmu);
@@ -7973,6 +8737,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
INIT_LIST_HEAD(&event->sibling_list);
INIT_LIST_HEAD(&event->rb_entry);
INIT_LIST_HEAD(&event->active_entry);
+ INIT_LIST_HEAD(&event->addr_filters.list);
INIT_HLIST_NODE(&event->hlist_entry);
@@ -7980,6 +8745,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
init_irq_work(&event->pending, perf_pending_event);
mutex_init(&event->mmap_mutex);
+ raw_spin_lock_init(&event->addr_filters.lock);
atomic_long_set(&event->refcount, 1);
event->cpu = cpu;
@@ -8014,8 +8780,16 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
context = parent_event->overflow_handler_context;
}
- event->overflow_handler = overflow_handler;
- event->overflow_handler_context = context;
+ if (overflow_handler) {
+ event->overflow_handler = overflow_handler;
+ event->overflow_handler_context = context;
+ } else if (is_write_backward(event)){
+ event->overflow_handler = perf_event_output_backward;
+ event->overflow_handler_context = NULL;
+ } else {
+ event->overflow_handler = perf_event_output_forward;
+ event->overflow_handler_context = NULL;
+ }
perf_event__state_init(event);
@@ -8056,11 +8830,22 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
if (err)
goto err_pmu;
+ if (has_addr_filter(event)) {
+ event->addr_filters_offs = kcalloc(pmu->nr_addr_filters,
+ sizeof(unsigned long),
+ GFP_KERNEL);
+ if (!event->addr_filters_offs)
+ goto err_per_task;
+
+ /* force hw sync on the address filters */
+ event->addr_filters_gen = 1;
+ }
+
if (!event->parent) {
if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {
err = get_callchain_buffers();
if (err)
- goto err_per_task;
+ goto err_addr_filters;
}
}
@@ -8069,6 +8854,9 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
return event;
+err_addr_filters:
+ kfree(event->addr_filters_offs);
+
err_per_task:
exclusive_event_destroy(event);
@@ -8248,6 +9036,13 @@ perf_event_set_output(struct perf_event *event, struct perf_event *output_event)
goto out;
/*
+ * Either writing ring buffer from beginning or from end.
+ * Mixing is not allowed.
+ */
+ if (is_write_backward(output_event) != is_write_backward(event))
+ goto out;
+
+ /*
* If both events generate aux data, they must be on the same PMU
*/
if (has_aux(event) && has_aux(output_event) &&
@@ -8413,6 +9208,24 @@ SYSCALL_DEFINE5(perf_event_open,
get_online_cpus();
+ if (task) {
+ err = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
+ if (err)
+ goto err_cpus;
+
+ /*
+ * Reuse ptrace permission checks for now.
+ *
+ * We must hold cred_guard_mutex across this and any potential
+ * perf_install_in_context() call for this new event to
+ * serialize against exec() altering our credentials (and the
+ * perf_event_exit_task() that could imply).
+ */
+ err = -EACCES;
+ if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS))
+ goto err_cred;
+ }
+
if (flags & PERF_FLAG_PID_CGROUP)
cgroup_fd = pid;
@@ -8420,7 +9233,7 @@ SYSCALL_DEFINE5(perf_event_open,
NULL, NULL, cgroup_fd);
if (IS_ERR(event)) {
err = PTR_ERR(event);
- goto err_cpus;
+ goto err_cred;
}
if (is_sampling_event(event)) {
@@ -8479,11 +9292,6 @@ SYSCALL_DEFINE5(perf_event_open,
goto err_context;
}
- if (task) {
- put_task_struct(task);
- task = NULL;
- }
-
/*
* Look up the group leader (we will attach this event to it):
*/
@@ -8581,6 +9389,11 @@ SYSCALL_DEFINE5(perf_event_open,
WARN_ON_ONCE(ctx->parent_ctx);
+ /*
+ * This is the point on no return; we cannot fail hereafter. This is
+ * where we start modifying current state.
+ */
+
if (move_group) {
/*
* See perf_event_ctx_lock() for comments on the details
@@ -8652,6 +9465,11 @@ SYSCALL_DEFINE5(perf_event_open,
mutex_unlock(&gctx->mutex);
mutex_unlock(&ctx->mutex);
+ if (task) {
+ mutex_unlock(&task->signal->cred_guard_mutex);
+ put_task_struct(task);
+ }
+
put_online_cpus();
mutex_lock(&current->perf_event_mutex);
@@ -8684,6 +9502,9 @@ err_alloc:
*/
if (!event_file)
free_event(event);
+err_cred:
+ if (task)
+ mutex_unlock(&task->signal->cred_guard_mutex);
err_cpus:
put_online_cpus();
err_task:
@@ -8968,6 +9789,9 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn)
/*
* When a child task exits, feed back event values to parent events.
+ *
+ * Can be called with cred_guard_mutex held when called from
+ * install_exec_creds().
*/
void perf_event_exit_task(struct task_struct *child)
{
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index 4199b6d193f5..05f9f6d626df 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -11,13 +11,13 @@
struct ring_buffer {
atomic_t refcount;
struct rcu_head rcu_head;
- struct irq_work irq_work;
#ifdef CONFIG_PERF_USE_VMALLOC
struct work_struct work;
int page_order; /* allocation order */
#endif
int nr_pages; /* nr of data pages */
int overwrite; /* can overwrite itself */
+ int paused; /* can write into ring buffer */
atomic_t poll; /* POLL_ for wakeups */
@@ -65,6 +65,14 @@ static inline void rb_free_rcu(struct rcu_head *rcu_head)
rb_free(rb);
}
+static inline void rb_toggle_paused(struct ring_buffer *rb, bool pause)
+{
+ if (!pause && rb->nr_pages)
+ rb->paused = 0;
+ else
+ rb->paused = 1;
+}
+
extern struct ring_buffer *
rb_alloc(int nr_pages, long watermark, int cpu, int flags);
extern void perf_event_wakeup(struct perf_event *event);
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index c61f0cbd308b..ae9b90dc9a5a 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -102,8 +102,21 @@ out:
preempt_enable();
}
-int perf_output_begin(struct perf_output_handle *handle,
- struct perf_event *event, unsigned int size)
+static bool __always_inline
+ring_buffer_has_space(unsigned long head, unsigned long tail,
+ unsigned long data_size, unsigned int size,
+ bool backward)
+{
+ if (!backward)
+ return CIRC_SPACE(head, tail, data_size) >= size;
+ else
+ return CIRC_SPACE(tail, head, data_size) >= size;
+}
+
+static int __always_inline
+__perf_output_begin(struct perf_output_handle *handle,
+ struct perf_event *event, unsigned int size,
+ bool backward)
{
struct ring_buffer *rb;
unsigned long tail, offset, head;
@@ -125,8 +138,11 @@ int perf_output_begin(struct perf_output_handle *handle,
if (unlikely(!rb))
goto out;
- if (unlikely(!rb->nr_pages))
+ if (unlikely(rb->paused)) {
+ if (rb->nr_pages)
+ local_inc(&rb->lost);
goto out;
+ }
handle->rb = rb;
handle->event = event;
@@ -143,9 +159,12 @@ int perf_output_begin(struct perf_output_handle *handle,
do {
tail = READ_ONCE(rb->user_page->data_tail);
offset = head = local_read(&rb->head);
- if (!rb->overwrite &&
- unlikely(CIRC_SPACE(head, tail, perf_data_size(rb)) < size))
- goto fail;
+ if (!rb->overwrite) {
+ if (unlikely(!ring_buffer_has_space(head, tail,
+ perf_data_size(rb),
+ size, backward)))
+ goto fail;
+ }
/*
* The above forms a control dependency barrier separating the
@@ -159,9 +178,17 @@ int perf_output_begin(struct perf_output_handle *handle,
* See perf_output_put_handle().
*/
- head += size;
+ if (!backward)
+ head += size;
+ else
+ head -= size;
} while (local_cmpxchg(&rb->head, offset, head) != offset);
+ if (backward) {
+ offset = head;
+ head = (u64)(-head);
+ }
+
/*
* We rely on the implied barrier() by local_cmpxchg() to ensure
* none of the data stores below can be lifted up by the compiler.
@@ -203,6 +230,26 @@ out:
return -ENOSPC;
}
+int perf_output_begin_forward(struct perf_output_handle *handle,
+ struct perf_event *event, unsigned int size)
+{
+ return __perf_output_begin(handle, event, size, false);
+}
+
+int perf_output_begin_backward(struct perf_output_handle *handle,
+ struct perf_event *event, unsigned int size)
+{
+ return __perf_output_begin(handle, event, size, true);
+}
+
+int perf_output_begin(struct perf_output_handle *handle,
+ struct perf_event *event, unsigned int size)
+{
+
+ return __perf_output_begin(handle, event, size,
+ unlikely(is_write_backward(event)));
+}
+
unsigned int perf_output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len)
{
@@ -221,8 +268,6 @@ void perf_output_end(struct perf_output_handle *handle)
rcu_read_unlock();
}
-static void rb_irq_work(struct irq_work *work);
-
static void
ring_buffer_init(struct ring_buffer *rb, long watermark, int flags)
{
@@ -243,16 +288,13 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags)
INIT_LIST_HEAD(&rb->event_list);
spin_lock_init(&rb->event_lock);
- init_irq_work(&rb->irq_work, rb_irq_work);
-}
-static void ring_buffer_put_async(struct ring_buffer *rb)
-{
- if (!atomic_dec_and_test(&rb->refcount))
- return;
-
- rb->rcu_head.next = (void *)rb;
- irq_work_queue(&rb->irq_work);
+ /*
+ * perf_output_begin() only checks rb->paused, therefore
+ * rb->paused must be true if we have no pages for output.
+ */
+ if (!rb->nr_pages)
+ rb->paused = 1;
}
/*
@@ -264,6 +306,10 @@ static void ring_buffer_put_async(struct ring_buffer *rb)
* The ordering is similar to that of perf_output_{begin,end}, with
* the exception of (B), which should be taken care of by the pmu
* driver, since ordering rules will differ depending on hardware.
+ *
+ * Call this from pmu::start(); see the comment in perf_aux_output_end()
+ * about its use in pmu callbacks. Both can also be called from the PMI
+ * handler if needed.
*/
void *perf_aux_output_begin(struct perf_output_handle *handle,
struct perf_event *event)
@@ -288,6 +334,13 @@ void *perf_aux_output_begin(struct perf_output_handle *handle,
goto err;
/*
+ * If rb::aux_mmap_count is zero (and rb_has_aux() above went through),
+ * the aux buffer is in perf_mmap_close(), about to get freed.
+ */
+ if (!atomic_read(&rb->aux_mmap_count))
+ goto err_put;
+
+ /*
* Nesting is not supported for AUX area, make sure nested
* writers are caught early
*/
@@ -328,10 +381,11 @@ void *perf_aux_output_begin(struct perf_output_handle *handle,
return handle->rb->aux_priv;
err_put:
+ /* can't be last */
rb_free_aux(rb);
err:
- ring_buffer_put_async(rb);
+ ring_buffer_put(rb);
handle->event = NULL;
return NULL;
@@ -342,11 +396,16 @@ err:
* aux_head and posting a PERF_RECORD_AUX into the perf buffer. It is the
* pmu driver's responsibility to observe ordering rules of the hardware,
* so that all the data is externally visible before this is called.
+ *
+ * Note: this has to be called from pmu::stop() callback, as the assumption
+ * of the AUX buffer management code is that after pmu::stop(), the AUX
+ * transaction must be stopped and therefore drop the AUX reference count.
*/
void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size,
bool truncated)
{
struct ring_buffer *rb = handle->rb;
+ bool wakeup = truncated;
unsigned long aux_head;
u64 flags = 0;
@@ -375,14 +434,22 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size,
aux_head = rb->user_page->aux_head = local_read(&rb->aux_head);
if (aux_head - local_read(&rb->aux_wakeup) >= rb->aux_watermark) {
- perf_output_wakeup(handle);
+ wakeup = true;
local_add(rb->aux_watermark, &rb->aux_wakeup);
}
+
+ if (wakeup) {
+ if (truncated)
+ handle->event->pending_disable = 1;
+ perf_output_wakeup(handle);
+ }
+
handle->event = NULL;
local_set(&rb->aux_nest, 0);
+ /* can't be last */
rb_free_aux(rb);
- ring_buffer_put_async(rb);
+ ring_buffer_put(rb);
}
/*
@@ -463,6 +530,14 @@ static void __rb_free_aux(struct ring_buffer *rb)
{
int pg;
+ /*
+ * Should never happen, the last reference should be dropped from
+ * perf_mmap_close() path, which first stops aux transactions (which
+ * in turn are the atomic holders of aux_refcount) and then does the
+ * last rb_free_aux().
+ */
+ WARN_ON_ONCE(in_atomic());
+
if (rb->aux_priv) {
rb->free_aux(rb->aux_priv);
rb->free_aux = NULL;
@@ -574,18 +649,7 @@ out:
void rb_free_aux(struct ring_buffer *rb)
{
if (atomic_dec_and_test(&rb->aux_refcount))
- irq_work_queue(&rb->irq_work);
-}
-
-static void rb_irq_work(struct irq_work *work)
-{
- struct ring_buffer *rb = container_of(work, struct ring_buffer, irq_work);
-
- if (!atomic_read(&rb->aux_refcount))
__rb_free_aux(rb);
-
- if (rb->rcu_head.next == (void *)rb)
- call_rcu(&rb->rcu_head, rb_free_rcu);
}
#ifndef CONFIG_PERF_USE_VMALLOC
diff --git a/kernel/fork.c b/kernel/fork.c
index d277e83ed3e0..3e8451527cbe 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1494,7 +1494,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
* sigaltstack should be cleared when sharing the same VM
*/
if ((clone_flags & (CLONE_VM|CLONE_VFORK)) == CLONE_VM)
- p->sas_ss_sp = p->sas_ss_size = 0;
+ sas_ss_reset(p);
/*
* Syscall tracing and stepping should be turned off in the
diff --git a/kernel/kcov.c b/kernel/kcov.c
index 3efbee0834a8..a02f2dddd1d7 100644
--- a/kernel/kcov.c
+++ b/kernel/kcov.c
@@ -1,5 +1,6 @@
#define pr_fmt(fmt) "kcov: " fmt
+#define DISABLE_BRANCH_PROFILING
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/file.h>
@@ -43,7 +44,7 @@ struct kcov {
* Entry point from instrumented code.
* This is called once per basic-block/edge.
*/
-void __sanitizer_cov_trace_pc(void)
+void notrace __sanitizer_cov_trace_pc(void)
{
struct task_struct *t;
enum kcov_mode mode;
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 8d34308ea449..1391d3ee3b86 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -1415,6 +1415,9 @@ static int __init crash_save_vmcoreinfo_init(void)
VMCOREINFO_OFFSET(page, lru);
VMCOREINFO_OFFSET(page, _mapcount);
VMCOREINFO_OFFSET(page, private);
+ VMCOREINFO_OFFSET(page, compound_dtor);
+ VMCOREINFO_OFFSET(page, compound_order);
+ VMCOREINFO_OFFSET(page, compound_head);
VMCOREINFO_OFFSET(pglist_data, node_zones);
VMCOREINFO_OFFSET(pglist_data, nr_zones);
#ifdef CONFIG_FLAT_NODE_MEM_MAP
@@ -1447,8 +1450,8 @@ static int __init crash_save_vmcoreinfo_init(void)
#ifdef CONFIG_X86
VMCOREINFO_NUMBER(KERNEL_IMAGE_SIZE);
#endif
-#ifdef CONFIG_HUGETLBFS
- VMCOREINFO_SYMBOL(free_huge_page);
+#ifdef CONFIG_HUGETLB_PAGE
+ VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR);
#endif
arch_crash_save_vmcoreinfo();
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index ed9410936a22..81f1a7107c0e 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -45,6 +45,7 @@
#include <linux/bitops.h>
#include <linux/gfp.h>
#include <linux/kmemcheck.h>
+#include <linux/random.h>
#include <asm/sections.h>
@@ -708,7 +709,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
* yet. Otherwise we look it up. We cache the result in the lock object
* itself, so actual lookup of the hash should be once per lock object.
*/
-static inline struct lock_class *
+static struct lock_class *
register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
{
struct lockdep_subclass_key *key;
@@ -2176,15 +2177,37 @@ cache_hit:
chain->irq_context = hlock->irq_context;
i = get_first_held_lock(curr, hlock);
chain->depth = curr->lockdep_depth + 1 - i;
+
+ BUILD_BUG_ON((1UL << 24) <= ARRAY_SIZE(chain_hlocks));
+ BUILD_BUG_ON((1UL << 6) <= ARRAY_SIZE(curr->held_locks));
+ BUILD_BUG_ON((1UL << 8*sizeof(chain_hlocks[0])) <= ARRAY_SIZE(lock_classes));
+
if (likely(nr_chain_hlocks + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) {
chain->base = nr_chain_hlocks;
- nr_chain_hlocks += chain->depth;
for (j = 0; j < chain->depth - 1; j++, i++) {
int lock_id = curr->held_locks[i].class_idx - 1;
chain_hlocks[chain->base + j] = lock_id;
}
chain_hlocks[chain->base + j] = class - lock_classes;
}
+
+ if (nr_chain_hlocks < MAX_LOCKDEP_CHAIN_HLOCKS)
+ nr_chain_hlocks += chain->depth;
+
+#ifdef CONFIG_DEBUG_LOCKDEP
+ /*
+ * Important for check_no_collision().
+ */
+ if (unlikely(nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)) {
+ if (debug_locks_off_graph_unlock())
+ return 0;
+
+ print_lockdep_off("BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!");
+ dump_stack();
+ return 0;
+ }
+#endif
+
hlist_add_head_rcu(&chain->entry, hash_head);
debug_atomic_inc(chain_lookup_misses);
inc_chains();
@@ -2932,6 +2955,11 @@ static int mark_irqflags(struct task_struct *curr, struct held_lock *hlock)
return 1;
}
+static inline unsigned int task_irq_context(struct task_struct *task)
+{
+ return 2 * !!task->hardirq_context + !!task->softirq_context;
+}
+
static int separate_irq_context(struct task_struct *curr,
struct held_lock *hlock)
{
@@ -2940,8 +2968,6 @@ static int separate_irq_context(struct task_struct *curr,
/*
* Keep track of points where we cross into an interrupt context:
*/
- hlock->irq_context = 2*(curr->hardirq_context ? 1 : 0) +
- curr->softirq_context;
if (depth) {
struct held_lock *prev_hlock;
@@ -2973,6 +2999,11 @@ static inline int mark_irqflags(struct task_struct *curr,
return 1;
}
+static inline unsigned int task_irq_context(struct task_struct *task)
+{
+ return 0;
+}
+
static inline int separate_irq_context(struct task_struct *curr,
struct held_lock *hlock)
{
@@ -3241,6 +3272,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
hlock->acquire_ip = ip;
hlock->instance = lock;
hlock->nest_lock = nest_lock;
+ hlock->irq_context = task_irq_context(curr);
hlock->trylock = trylock;
hlock->read = read;
hlock->check = check;
@@ -3554,7 +3586,35 @@ static int __lock_is_held(struct lockdep_map *lock)
return 0;
}
-static void __lock_pin_lock(struct lockdep_map *lock)
+static struct pin_cookie __lock_pin_lock(struct lockdep_map *lock)
+{
+ struct pin_cookie cookie = NIL_COOKIE;
+ struct task_struct *curr = current;
+ int i;
+
+ if (unlikely(!debug_locks))
+ return cookie;
+
+ for (i = 0; i < curr->lockdep_depth; i++) {
+ struct held_lock *hlock = curr->held_locks + i;
+
+ if (match_held_lock(hlock, lock)) {
+ /*
+ * Grab 16bits of randomness; this is sufficient to not
+ * be guessable and still allows some pin nesting in
+ * our u32 pin_count.
+ */
+ cookie.val = 1 + (prandom_u32() >> 16);
+ hlock->pin_count += cookie.val;
+ return cookie;
+ }
+ }
+
+ WARN(1, "pinning an unheld lock\n");
+ return cookie;
+}
+
+static void __lock_repin_lock(struct lockdep_map *lock, struct pin_cookie cookie)
{
struct task_struct *curr = current;
int i;
@@ -3566,7 +3626,7 @@ static void __lock_pin_lock(struct lockdep_map *lock)
struct held_lock *hlock = curr->held_locks + i;
if (match_held_lock(hlock, lock)) {
- hlock->pin_count++;
+ hlock->pin_count += cookie.val;
return;
}
}
@@ -3574,7 +3634,7 @@ static void __lock_pin_lock(struct lockdep_map *lock)
WARN(1, "pinning an unheld lock\n");
}
-static void __lock_unpin_lock(struct lockdep_map *lock)
+static void __lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie cookie)
{
struct task_struct *curr = current;
int i;
@@ -3589,7 +3649,11 @@ static void __lock_unpin_lock(struct lockdep_map *lock)
if (WARN(!hlock->pin_count, "unpinning an unpinned lock\n"))
return;
- hlock->pin_count--;
+ hlock->pin_count -= cookie.val;
+
+ if (WARN((int)hlock->pin_count < 0, "pin count corrupted\n"))
+ hlock->pin_count = 0;
+
return;
}
}
@@ -3720,24 +3784,44 @@ int lock_is_held(struct lockdep_map *lock)
}
EXPORT_SYMBOL_GPL(lock_is_held);
-void lock_pin_lock(struct lockdep_map *lock)
+struct pin_cookie lock_pin_lock(struct lockdep_map *lock)
{
+ struct pin_cookie cookie = NIL_COOKIE;
unsigned long flags;
if (unlikely(current->lockdep_recursion))
- return;
+ return cookie;
raw_local_irq_save(flags);
check_flags(flags);
current->lockdep_recursion = 1;
- __lock_pin_lock(lock);
+ cookie = __lock_pin_lock(lock);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
+
+ return cookie;
}
EXPORT_SYMBOL_GPL(lock_pin_lock);
-void lock_unpin_lock(struct lockdep_map *lock)
+void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie cookie)
+{
+ unsigned long flags;
+
+ if (unlikely(current->lockdep_recursion))
+ return;
+
+ raw_local_irq_save(flags);
+ check_flags(flags);
+
+ current->lockdep_recursion = 1;
+ __lock_repin_lock(lock, cookie);
+ current->lockdep_recursion = 0;
+ raw_local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(lock_repin_lock);
+
+void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie cookie)
{
unsigned long flags;
@@ -3748,7 +3832,7 @@ void lock_unpin_lock(struct lockdep_map *lock)
check_flags(flags);
current->lockdep_recursion = 1;
- __lock_unpin_lock(lock);
+ __lock_unpin_lock(lock, cookie);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index dbb61a302548..a0f61effad25 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -141,6 +141,8 @@ static int lc_show(struct seq_file *m, void *v)
int i;
if (v == SEQ_START_TOKEN) {
+ if (nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)
+ seq_printf(m, "(buggered) ");
seq_printf(m, "all lock chains:\n");
return 0;
}
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index 8ef1919d63b2..f8c5af52a131 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -75,12 +75,7 @@ struct lock_stress_stats {
long n_lock_acquired;
};
-#if defined(MODULE)
-#define LOCKTORTURE_RUNNABLE_INIT 1
-#else
-#define LOCKTORTURE_RUNNABLE_INIT 0
-#endif
-int torture_runnable = LOCKTORTURE_RUNNABLE_INIT;
+int torture_runnable = IS_ENABLED(MODULE);
module_param(torture_runnable, int, 0444);
MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init");
@@ -394,12 +389,12 @@ static void torture_rtmutex_boost(struct torture_random_state *trsp)
if (!rt_task(current)) {
/*
- * (1) Boost priority once every ~50k operations. When the
+ * Boost priority once every ~50k operations. When the
* task tries to take the lock, the rtmutex it will account
* for the new priority, and do any corresponding pi-dance.
*/
- if (!(torture_random(trsp) %
- (cxt.nrealwriters_stress * factor))) {
+ if (trsp && !(torture_random(trsp) %
+ (cxt.nrealwriters_stress * factor))) {
policy = SCHED_FIFO;
param.sched_priority = MAX_RT_PRIO - 1;
} else /* common case, do nothing */
@@ -748,6 +743,15 @@ static void lock_torture_cleanup(void)
if (torture_cleanup_begin())
return;
+ /*
+ * Indicates early cleanup, meaning that the test has not run,
+ * such as when passing bogus args when loading the module. As
+ * such, only perform the underlying torture-specific cleanups,
+ * and avoid anything related to locktorture.
+ */
+ if (!cxt.lwsa)
+ goto end;
+
if (writer_tasks) {
for (i = 0; i < cxt.nrealwriters_stress; i++)
torture_stop_kthread(lock_torture_writer,
@@ -776,6 +780,7 @@ static void lock_torture_cleanup(void)
else
lock_torture_print_module_parms(cxt.cur_ops,
"End of test: SUCCESS");
+end:
torture_cleanup_end();
}
@@ -870,6 +875,7 @@ static int __init lock_torture_init(void)
VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
firsterr = -ENOMEM;
kfree(cxt.lwsa);
+ cxt.lwsa = NULL;
goto unwind;
}
@@ -878,6 +884,7 @@ static int __init lock_torture_init(void)
cxt.lrsa[i].n_lock_acquired = 0;
}
}
+
lock_torture_print_module_parms(cxt.cur_ops, "Start of test");
/* Prepare torture context. */
diff --git a/kernel/locking/qspinlock_stat.h b/kernel/locking/qspinlock_stat.h
index d734b7502001..22e025309845 100644
--- a/kernel/locking/qspinlock_stat.h
+++ b/kernel/locking/qspinlock_stat.h
@@ -191,8 +191,6 @@ static ssize_t qstat_write(struct file *file, const char __user *user_buf,
for (i = 0 ; i < qstat_num; i++)
WRITE_ONCE(ptr[i], 0);
- for (i = 0 ; i < qstat_num; i++)
- WRITE_ONCE(ptr[i], 0);
}
return count;
}
@@ -214,10 +212,8 @@ static int __init init_qspinlock_stat(void)
struct dentry *d_qstat = debugfs_create_dir("qlockstat", NULL);
int i;
- if (!d_qstat) {
- pr_warn("Could not create 'qlockstat' debugfs directory\n");
- return 0;
- }
+ if (!d_qstat)
+ goto out;
/*
* Create the debugfs files
@@ -227,12 +223,20 @@ static int __init init_qspinlock_stat(void)
* performance.
*/
for (i = 0; i < qstat_num; i++)
- debugfs_create_file(qstat_names[i], 0400, d_qstat,
- (void *)(long)i, &fops_qstat);
+ if (!debugfs_create_file(qstat_names[i], 0400, d_qstat,
+ (void *)(long)i, &fops_qstat))
+ goto fail_undo;
+
+ if (!debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat,
+ (void *)(long)qstat_reset_cnts, &fops_qstat))
+ goto fail_undo;
- debugfs_create_file(qstat_names[qstat_reset_cnts], 0200, d_qstat,
- (void *)(long)qstat_reset_cnts, &fops_qstat);
return 0;
+fail_undo:
+ debugfs_remove_recursive(d_qstat);
+out:
+ pr_warn("Could not create 'qlockstat' debugfs entries\n");
+ return -ENOMEM;
}
fs_initcall(init_qspinlock_stat);
diff --git a/kernel/locking/rwsem-spinlock.c b/kernel/locking/rwsem-spinlock.c
index 3a5048572065..1591f6b3539f 100644
--- a/kernel/locking/rwsem-spinlock.c
+++ b/kernel/locking/rwsem-spinlock.c
@@ -191,11 +191,12 @@ int __down_read_trylock(struct rw_semaphore *sem)
/*
* get a write lock on the semaphore
*/
-void __sched __down_write_nested(struct rw_semaphore *sem, int subclass)
+int __sched __down_write_common(struct rw_semaphore *sem, int state)
{
struct rwsem_waiter waiter;
struct task_struct *tsk;
unsigned long flags;
+ int ret = 0;
raw_spin_lock_irqsave(&sem->wait_lock, flags);
@@ -215,21 +216,33 @@ void __sched __down_write_nested(struct rw_semaphore *sem, int subclass)
*/
if (sem->count == 0)
break;
- set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+ if (signal_pending_state(state, current)) {
+ ret = -EINTR;
+ goto out;
+ }
+ set_task_state(tsk, state);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
schedule();
raw_spin_lock_irqsave(&sem->wait_lock, flags);
}
/* got the lock */
sem->count = -1;
+out:
list_del(&waiter.list);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
+
+ return ret;
}
void __sched __down_write(struct rw_semaphore *sem)
{
- __down_write_nested(sem, 0);
+ __down_write_common(sem, TASK_UNINTERRUPTIBLE);
+}
+
+int __sched __down_write_killable(struct rw_semaphore *sem)
+{
+ return __down_write_common(sem, TASK_KILLABLE);
}
/*
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index a4d4de05b2d1..09e30c6225e5 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -433,12 +433,13 @@ static inline bool rwsem_has_spinner(struct rw_semaphore *sem)
/*
* Wait until we successfully acquire the write lock
*/
-__visible
-struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
+static inline struct rw_semaphore *
+__rwsem_down_write_failed_common(struct rw_semaphore *sem, int state)
{
long count;
bool waiting = true; /* any queued threads before us */
struct rwsem_waiter waiter;
+ struct rw_semaphore *ret = sem;
/* undo write bias from down_write operation, stop active locking */
count = rwsem_atomic_update(-RWSEM_ACTIVE_WRITE_BIAS, sem);
@@ -478,7 +479,7 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
count = rwsem_atomic_update(RWSEM_WAITING_BIAS, sem);
/* wait until we successfully acquire the lock */
- set_current_state(TASK_UNINTERRUPTIBLE);
+ set_current_state(state);
while (true) {
if (rwsem_try_write_lock(count, sem))
break;
@@ -486,21 +487,48 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
/* Block until there are no active lockers. */
do {
+ if (signal_pending_state(state, current))
+ goto out_nolock;
+
schedule();
- set_current_state(TASK_UNINTERRUPTIBLE);
+ set_current_state(state);
} while ((count = sem->count) & RWSEM_ACTIVE_MASK);
raw_spin_lock_irq(&sem->wait_lock);
}
__set_current_state(TASK_RUNNING);
+ list_del(&waiter.list);
+ raw_spin_unlock_irq(&sem->wait_lock);
+ return ret;
+
+out_nolock:
+ __set_current_state(TASK_RUNNING);
+ raw_spin_lock_irq(&sem->wait_lock);
list_del(&waiter.list);
+ if (list_empty(&sem->wait_list))
+ rwsem_atomic_update(-RWSEM_WAITING_BIAS, sem);
+ else
+ __rwsem_do_wake(sem, RWSEM_WAKE_ANY);
raw_spin_unlock_irq(&sem->wait_lock);
- return sem;
+ return ERR_PTR(-EINTR);
+}
+
+__visible struct rw_semaphore * __sched
+rwsem_down_write_failed(struct rw_semaphore *sem)
+{
+ return __rwsem_down_write_failed_common(sem, TASK_UNINTERRUPTIBLE);
}
EXPORT_SYMBOL(rwsem_down_write_failed);
+__visible struct rw_semaphore * __sched
+rwsem_down_write_failed_killable(struct rw_semaphore *sem)
+{
+ return __rwsem_down_write_failed_common(sem, TASK_KILLABLE);
+}
+EXPORT_SYMBOL(rwsem_down_write_failed_killable);
+
/*
* handle waking up a waiter on the semaphore
* - up_read/up_write has decremented the active part of count if we come here
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 205be0ce34de..c817216c1615 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -55,6 +55,25 @@ void __sched down_write(struct rw_semaphore *sem)
EXPORT_SYMBOL(down_write);
/*
+ * lock for writing
+ */
+int __sched down_write_killable(struct rw_semaphore *sem)
+{
+ might_sleep();
+ rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_);
+
+ if (LOCK_CONTENDED_RETURN(sem, __down_write_trylock, __down_write_killable)) {
+ rwsem_release(&sem->dep_map, 1, _RET_IP_);
+ return -EINTR;
+ }
+
+ rwsem_set_owner(sem);
+ return 0;
+}
+
+EXPORT_SYMBOL(down_write_killable);
+
+/*
* trylock for writing -- returns 1 if successful, 0 if contention
*/
int down_write_trylock(struct rw_semaphore *sem)
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 12cd989dadf6..160e1006640d 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -37,6 +37,14 @@
#define HIBERNATE_SIG "S1SUSPEND"
/*
+ * When reading an {un,}compressed image, we may restore pages in place,
+ * in which case some architectures need these pages cleaning before they
+ * can be executed. We don't know which pages these may be, so clean the lot.
+ */
+static bool clean_pages_on_read;
+static bool clean_pages_on_decompress;
+
+/*
* The swap map is a data structure used for keeping track of each page
* written to a swap partition. It consists of many swap_map_page
* structures that contain each an array of MAP_PAGE_ENTRIES swap entries.
@@ -241,6 +249,9 @@ static void hib_end_io(struct bio *bio)
if (bio_data_dir(bio) == WRITE)
put_page(page);
+ else if (clean_pages_on_read)
+ flush_icache_range((unsigned long)page_address(page),
+ (unsigned long)page_address(page) + PAGE_SIZE);
if (bio->bi_error && !hb->error)
hb->error = bio->bi_error;
@@ -1049,6 +1060,7 @@ static int load_image(struct swap_map_handle *handle,
hib_init_batch(&hb);
+ clean_pages_on_read = true;
printk(KERN_INFO "PM: Loading image data pages (%u pages)...\n",
nr_to_read);
m = nr_to_read / 10;
@@ -1124,6 +1136,10 @@ static int lzo_decompress_threadfn(void *data)
d->unc_len = LZO_UNC_SIZE;
d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
d->unc, &d->unc_len);
+ if (clean_pages_on_decompress)
+ flush_icache_range((unsigned long)d->unc,
+ (unsigned long)d->unc + d->unc_len);
+
atomic_set(&d->stop, 1);
wake_up(&d->done);
}
@@ -1189,6 +1205,8 @@ static int load_image_lzo(struct swap_map_handle *handle,
}
memset(crc, 0, offsetof(struct crc_data, go));
+ clean_pages_on_decompress = true;
+
/*
* Start the decompression threads.
*/
diff --git a/kernel/rcu/Makefile b/kernel/rcu/Makefile
index 032b2c015beb..18dfc485225c 100644
--- a/kernel/rcu/Makefile
+++ b/kernel/rcu/Makefile
@@ -5,6 +5,7 @@ KCOV_INSTRUMENT := n
obj-y += update.o sync.o
obj-$(CONFIG_SRCU) += srcu.o
obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
+obj-$(CONFIG_RCU_PERF_TEST) += rcuperf.o
obj-$(CONFIG_TREE_RCU) += tree.o
obj-$(CONFIG_PREEMPT_RCU) += tree.o
obj-$(CONFIG_TREE_RCU_TRACE) += tree_trace.o
diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
new file mode 100644
index 000000000000..3cee0d8393ed
--- /dev/null
+++ b/kernel/rcu/rcuperf.c
@@ -0,0 +1,655 @@
+/*
+ * Read-Copy Update module-based performance-test facility
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2015
+ *
+ * Authors: Paul E. McKenney <paulmck@us.ibm.com>
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/rcupdate.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/stat.h>
+#include <linux/srcu.h>
+#include <linux/slab.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+#include <linux/vmalloc.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.vnet.ibm.com>");
+
+#define PERF_FLAG "-perf:"
+#define PERFOUT_STRING(s) \
+ pr_alert("%s" PERF_FLAG s "\n", perf_type)
+#define VERBOSE_PERFOUT_STRING(s) \
+ do { if (verbose) pr_alert("%s" PERF_FLAG " %s\n", perf_type, s); } while (0)
+#define VERBOSE_PERFOUT_ERRSTRING(s) \
+ do { if (verbose) pr_alert("%s" PERF_FLAG "!!! %s\n", perf_type, s); } while (0)
+
+torture_param(bool, gp_exp, true, "Use expedited GP wait primitives");
+torture_param(int, holdoff, 10, "Holdoff time before test start (s)");
+torture_param(int, nreaders, -1, "Number of RCU reader threads");
+torture_param(int, nwriters, -1, "Number of RCU updater threads");
+torture_param(bool, shutdown, false, "Shutdown at end of performance tests.");
+torture_param(bool, verbose, true, "Enable verbose debugging printk()s");
+
+static char *perf_type = "rcu";
+module_param(perf_type, charp, 0444);
+MODULE_PARM_DESC(perf_type, "Type of RCU to performance-test (rcu, rcu_bh, ...)");
+
+static int nrealreaders;
+static int nrealwriters;
+static struct task_struct **writer_tasks;
+static struct task_struct **reader_tasks;
+static struct task_struct *shutdown_task;
+
+static u64 **writer_durations;
+static int *writer_n_durations;
+static atomic_t n_rcu_perf_reader_started;
+static atomic_t n_rcu_perf_writer_started;
+static atomic_t n_rcu_perf_writer_finished;
+static wait_queue_head_t shutdown_wq;
+static u64 t_rcu_perf_writer_started;
+static u64 t_rcu_perf_writer_finished;
+static unsigned long b_rcu_perf_writer_started;
+static unsigned long b_rcu_perf_writer_finished;
+
+static int rcu_perf_writer_state;
+#define RTWS_INIT 0
+#define RTWS_EXP_SYNC 1
+#define RTWS_SYNC 2
+#define RTWS_IDLE 2
+#define RTWS_STOPPING 3
+
+#define MAX_MEAS 10000
+#define MIN_MEAS 100
+
+#if defined(MODULE) || defined(CONFIG_RCU_PERF_TEST_RUNNABLE)
+#define RCUPERF_RUNNABLE_INIT 1
+#else
+#define RCUPERF_RUNNABLE_INIT 0
+#endif
+static int perf_runnable = RCUPERF_RUNNABLE_INIT;
+module_param(perf_runnable, int, 0444);
+MODULE_PARM_DESC(perf_runnable, "Start rcuperf at boot");
+
+/*
+ * Operations vector for selecting different types of tests.
+ */
+
+struct rcu_perf_ops {
+ int ptype;
+ void (*init)(void);
+ void (*cleanup)(void);
+ int (*readlock)(void);
+ void (*readunlock)(int idx);
+ unsigned long (*started)(void);
+ unsigned long (*completed)(void);
+ unsigned long (*exp_completed)(void);
+ void (*sync)(void);
+ void (*exp_sync)(void);
+ const char *name;
+};
+
+static struct rcu_perf_ops *cur_ops;
+
+/*
+ * Definitions for rcu perf testing.
+ */
+
+static int rcu_perf_read_lock(void) __acquires(RCU)
+{
+ rcu_read_lock();
+ return 0;
+}
+
+static void rcu_perf_read_unlock(int idx) __releases(RCU)
+{
+ rcu_read_unlock();
+}
+
+static unsigned long __maybe_unused rcu_no_completed(void)
+{
+ return 0;
+}
+
+static void rcu_sync_perf_init(void)
+{
+}
+
+static struct rcu_perf_ops rcu_ops = {
+ .ptype = RCU_FLAVOR,
+ .init = rcu_sync_perf_init,
+ .readlock = rcu_perf_read_lock,
+ .readunlock = rcu_perf_read_unlock,
+ .started = rcu_batches_started,
+ .completed = rcu_batches_completed,
+ .exp_completed = rcu_exp_batches_completed,
+ .sync = synchronize_rcu,
+ .exp_sync = synchronize_rcu_expedited,
+ .name = "rcu"
+};
+
+/*
+ * Definitions for rcu_bh perf testing.
+ */
+
+static int rcu_bh_perf_read_lock(void) __acquires(RCU_BH)
+{
+ rcu_read_lock_bh();
+ return 0;
+}
+
+static void rcu_bh_perf_read_unlock(int idx) __releases(RCU_BH)
+{
+ rcu_read_unlock_bh();
+}
+
+static struct rcu_perf_ops rcu_bh_ops = {
+ .ptype = RCU_BH_FLAVOR,
+ .init = rcu_sync_perf_init,
+ .readlock = rcu_bh_perf_read_lock,
+ .readunlock = rcu_bh_perf_read_unlock,
+ .started = rcu_batches_started_bh,
+ .completed = rcu_batches_completed_bh,
+ .exp_completed = rcu_exp_batches_completed_sched,
+ .sync = synchronize_rcu_bh,
+ .exp_sync = synchronize_rcu_bh_expedited,
+ .name = "rcu_bh"
+};
+
+/*
+ * Definitions for srcu perf testing.
+ */
+
+DEFINE_STATIC_SRCU(srcu_ctl_perf);
+static struct srcu_struct *srcu_ctlp = &srcu_ctl_perf;
+
+static int srcu_perf_read_lock(void) __acquires(srcu_ctlp)
+{
+ return srcu_read_lock(srcu_ctlp);
+}
+
+static void srcu_perf_read_unlock(int idx) __releases(srcu_ctlp)
+{
+ srcu_read_unlock(srcu_ctlp, idx);
+}
+
+static unsigned long srcu_perf_completed(void)
+{
+ return srcu_batches_completed(srcu_ctlp);
+}
+
+static void srcu_perf_synchronize(void)
+{
+ synchronize_srcu(srcu_ctlp);
+}
+
+static void srcu_perf_synchronize_expedited(void)
+{
+ synchronize_srcu_expedited(srcu_ctlp);
+}
+
+static struct rcu_perf_ops srcu_ops = {
+ .ptype = SRCU_FLAVOR,
+ .init = rcu_sync_perf_init,
+ .readlock = srcu_perf_read_lock,
+ .readunlock = srcu_perf_read_unlock,
+ .started = NULL,
+ .completed = srcu_perf_completed,
+ .exp_completed = srcu_perf_completed,
+ .sync = srcu_perf_synchronize,
+ .exp_sync = srcu_perf_synchronize_expedited,
+ .name = "srcu"
+};
+
+/*
+ * Definitions for sched perf testing.
+ */
+
+static int sched_perf_read_lock(void)
+{
+ preempt_disable();
+ return 0;
+}
+
+static void sched_perf_read_unlock(int idx)
+{
+ preempt_enable();
+}
+
+static struct rcu_perf_ops sched_ops = {
+ .ptype = RCU_SCHED_FLAVOR,
+ .init = rcu_sync_perf_init,
+ .readlock = sched_perf_read_lock,
+ .readunlock = sched_perf_read_unlock,
+ .started = rcu_batches_started_sched,
+ .completed = rcu_batches_completed_sched,
+ .exp_completed = rcu_exp_batches_completed_sched,
+ .sync = synchronize_sched,
+ .exp_sync = synchronize_sched_expedited,
+ .name = "sched"
+};
+
+#ifdef CONFIG_TASKS_RCU
+
+/*
+ * Definitions for RCU-tasks perf testing.
+ */
+
+static int tasks_perf_read_lock(void)
+{
+ return 0;
+}
+
+static void tasks_perf_read_unlock(int idx)
+{
+}
+
+static struct rcu_perf_ops tasks_ops = {
+ .ptype = RCU_TASKS_FLAVOR,
+ .init = rcu_sync_perf_init,
+ .readlock = tasks_perf_read_lock,
+ .readunlock = tasks_perf_read_unlock,
+ .started = rcu_no_completed,
+ .completed = rcu_no_completed,
+ .sync = synchronize_rcu_tasks,
+ .exp_sync = synchronize_rcu_tasks,
+ .name = "tasks"
+};
+
+#define RCUPERF_TASKS_OPS &tasks_ops,
+
+static bool __maybe_unused torturing_tasks(void)
+{
+ return cur_ops == &tasks_ops;
+}
+
+#else /* #ifdef CONFIG_TASKS_RCU */
+
+#define RCUPERF_TASKS_OPS
+
+static bool __maybe_unused torturing_tasks(void)
+{
+ return false;
+}
+
+#endif /* #else #ifdef CONFIG_TASKS_RCU */
+
+/*
+ * If performance tests complete, wait for shutdown to commence.
+ */
+static void rcu_perf_wait_shutdown(void)
+{
+ cond_resched_rcu_qs();
+ if (atomic_read(&n_rcu_perf_writer_finished) < nrealwriters)
+ return;
+ while (!torture_must_stop())
+ schedule_timeout_uninterruptible(1);
+}
+
+/*
+ * RCU perf reader kthread. Repeatedly does empty RCU read-side
+ * critical section, minimizing update-side interference.
+ */
+static int
+rcu_perf_reader(void *arg)
+{
+ unsigned long flags;
+ int idx;
+ long me = (long)arg;
+
+ VERBOSE_PERFOUT_STRING("rcu_perf_reader task started");
+ set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids));
+ set_user_nice(current, MAX_NICE);
+ atomic_inc(&n_rcu_perf_reader_started);
+
+ do {
+ local_irq_save(flags);
+ idx = cur_ops->readlock();
+ cur_ops->readunlock(idx);
+ local_irq_restore(flags);
+ rcu_perf_wait_shutdown();
+ } while (!torture_must_stop());
+ torture_kthread_stopping("rcu_perf_reader");
+ return 0;
+}
+
+/*
+ * RCU perf writer kthread. Repeatedly does a grace period.
+ */
+static int
+rcu_perf_writer(void *arg)
+{
+ int i = 0;
+ int i_max;
+ long me = (long)arg;
+ struct sched_param sp;
+ bool started = false, done = false, alldone = false;
+ u64 t;
+ u64 *wdp;
+ u64 *wdpp = writer_durations[me];
+
+ VERBOSE_PERFOUT_STRING("rcu_perf_writer task started");
+ WARN_ON(rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp);
+ WARN_ON(rcu_gp_is_normal() && gp_exp);
+ WARN_ON(!wdpp);
+ set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids));
+ sp.sched_priority = 1;
+ sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+
+ if (holdoff)
+ schedule_timeout_uninterruptible(holdoff * HZ);
+
+ t = ktime_get_mono_fast_ns();
+ if (atomic_inc_return(&n_rcu_perf_writer_started) >= nrealwriters) {
+ t_rcu_perf_writer_started = t;
+ if (gp_exp) {
+ b_rcu_perf_writer_started =
+ cur_ops->exp_completed() / 2;
+ } else {
+ b_rcu_perf_writer_started =
+ cur_ops->completed();
+ }
+ }
+
+ do {
+ wdp = &wdpp[i];
+ *wdp = ktime_get_mono_fast_ns();
+ if (gp_exp) {
+ rcu_perf_writer_state = RTWS_EXP_SYNC;
+ cur_ops->exp_sync();
+ } else {
+ rcu_perf_writer_state = RTWS_SYNC;
+ cur_ops->sync();
+ }
+ rcu_perf_writer_state = RTWS_IDLE;
+ t = ktime_get_mono_fast_ns();
+ *wdp = t - *wdp;
+ i_max = i;
+ if (!started &&
+ atomic_read(&n_rcu_perf_writer_started) >= nrealwriters)
+ started = true;
+ if (!done && i >= MIN_MEAS) {
+ done = true;
+ sp.sched_priority = 0;
+ sched_setscheduler_nocheck(current,
+ SCHED_NORMAL, &sp);
+ pr_alert("%s" PERF_FLAG
+ "rcu_perf_writer %ld has %d measurements\n",
+ perf_type, me, MIN_MEAS);
+ if (atomic_inc_return(&n_rcu_perf_writer_finished) >=
+ nrealwriters) {
+ schedule_timeout_interruptible(10);
+ rcu_ftrace_dump(DUMP_ALL);
+ PERFOUT_STRING("Test complete");
+ t_rcu_perf_writer_finished = t;
+ if (gp_exp) {
+ b_rcu_perf_writer_finished =
+ cur_ops->exp_completed() / 2;
+ } else {
+ b_rcu_perf_writer_finished =
+ cur_ops->completed();
+ }
+ if (shutdown) {
+ smp_mb(); /* Assign before wake. */
+ wake_up(&shutdown_wq);
+ }
+ }
+ }
+ if (done && !alldone &&
+ atomic_read(&n_rcu_perf_writer_finished) >= nrealwriters)
+ alldone = true;
+ if (started && !alldone && i < MAX_MEAS - 1)
+ i++;
+ rcu_perf_wait_shutdown();
+ } while (!torture_must_stop());
+ rcu_perf_writer_state = RTWS_STOPPING;
+ writer_n_durations[me] = i_max;
+ torture_kthread_stopping("rcu_perf_writer");
+ return 0;
+}
+
+static inline void
+rcu_perf_print_module_parms(struct rcu_perf_ops *cur_ops, const char *tag)
+{
+ pr_alert("%s" PERF_FLAG
+ "--- %s: nreaders=%d nwriters=%d verbose=%d shutdown=%d\n",
+ perf_type, tag, nrealreaders, nrealwriters, verbose, shutdown);
+}
+
+static void
+rcu_perf_cleanup(void)
+{
+ int i;
+ int j;
+ int ngps = 0;
+ u64 *wdp;
+ u64 *wdpp;
+
+ if (torture_cleanup_begin())
+ return;
+
+ if (reader_tasks) {
+ for (i = 0; i < nrealreaders; i++)
+ torture_stop_kthread(rcu_perf_reader,
+ reader_tasks[i]);
+ kfree(reader_tasks);
+ }
+
+ if (writer_tasks) {
+ for (i = 0; i < nrealwriters; i++) {
+ torture_stop_kthread(rcu_perf_writer,
+ writer_tasks[i]);
+ if (!writer_n_durations)
+ continue;
+ j = writer_n_durations[i];
+ pr_alert("%s%s writer %d gps: %d\n",
+ perf_type, PERF_FLAG, i, j);
+ ngps += j;
+ }
+ pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n",
+ perf_type, PERF_FLAG,
+ t_rcu_perf_writer_started, t_rcu_perf_writer_finished,
+ t_rcu_perf_writer_finished -
+ t_rcu_perf_writer_started,
+ ngps,
+ b_rcu_perf_writer_finished -
+ b_rcu_perf_writer_started);
+ for (i = 0; i < nrealwriters; i++) {
+ if (!writer_durations)
+ break;
+ if (!writer_n_durations)
+ continue;
+ wdpp = writer_durations[i];
+ if (!wdpp)
+ continue;
+ for (j = 0; j <= writer_n_durations[i]; j++) {
+ wdp = &wdpp[j];
+ pr_alert("%s%s %4d writer-duration: %5d %llu\n",
+ perf_type, PERF_FLAG,
+ i, j, *wdp);
+ if (j % 100 == 0)
+ schedule_timeout_uninterruptible(1);
+ }
+ kfree(writer_durations[i]);
+ }
+ kfree(writer_tasks);
+ kfree(writer_durations);
+ kfree(writer_n_durations);
+ }
+
+ /* Do flavor-specific cleanup operations. */
+ if (cur_ops->cleanup != NULL)
+ cur_ops->cleanup();
+
+ torture_cleanup_end();
+}
+
+/*
+ * Return the number if non-negative. If -1, the number of CPUs.
+ * If less than -1, that much less than the number of CPUs, but
+ * at least one.
+ */
+static int compute_real(int n)
+{
+ int nr;
+
+ if (n >= 0) {
+ nr = n;
+ } else {
+ nr = num_online_cpus() + 1 + n;
+ if (nr <= 0)
+ nr = 1;
+ }
+ return nr;
+}
+
+/*
+ * RCU perf shutdown kthread. Just waits to be awakened, then shuts
+ * down system.
+ */
+static int
+rcu_perf_shutdown(void *arg)
+{
+ do {
+ wait_event(shutdown_wq,
+ atomic_read(&n_rcu_perf_writer_finished) >=
+ nrealwriters);
+ } while (atomic_read(&n_rcu_perf_writer_finished) < nrealwriters);
+ smp_mb(); /* Wake before output. */
+ rcu_perf_cleanup();
+ kernel_power_off();
+ return -EINVAL;
+}
+
+static int __init
+rcu_perf_init(void)
+{
+ long i;
+ int firsterr = 0;
+ static struct rcu_perf_ops *perf_ops[] = {
+ &rcu_ops, &rcu_bh_ops, &srcu_ops, &sched_ops,
+ RCUPERF_TASKS_OPS
+ };
+
+ if (!torture_init_begin(perf_type, verbose, &perf_runnable))
+ return -EBUSY;
+
+ /* Process args and tell the world that the perf'er is on the job. */
+ for (i = 0; i < ARRAY_SIZE(perf_ops); i++) {
+ cur_ops = perf_ops[i];
+ if (strcmp(perf_type, cur_ops->name) == 0)
+ break;
+ }
+ if (i == ARRAY_SIZE(perf_ops)) {
+ pr_alert("rcu-perf: invalid perf type: \"%s\"\n",
+ perf_type);
+ pr_alert("rcu-perf types:");
+ for (i = 0; i < ARRAY_SIZE(perf_ops); i++)
+ pr_alert(" %s", perf_ops[i]->name);
+ pr_alert("\n");
+ firsterr = -EINVAL;
+ goto unwind;
+ }
+ if (cur_ops->init)
+ cur_ops->init();
+
+ nrealwriters = compute_real(nwriters);
+ nrealreaders = compute_real(nreaders);
+ atomic_set(&n_rcu_perf_reader_started, 0);
+ atomic_set(&n_rcu_perf_writer_started, 0);
+ atomic_set(&n_rcu_perf_writer_finished, 0);
+ rcu_perf_print_module_parms(cur_ops, "Start of test");
+
+ /* Start up the kthreads. */
+
+ if (shutdown) {
+ init_waitqueue_head(&shutdown_wq);
+ firsterr = torture_create_kthread(rcu_perf_shutdown, NULL,
+ shutdown_task);
+ if (firsterr)
+ goto unwind;
+ schedule_timeout_uninterruptible(1);
+ }
+ reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]),
+ GFP_KERNEL);
+ if (reader_tasks == NULL) {
+ VERBOSE_PERFOUT_ERRSTRING("out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ for (i = 0; i < nrealreaders; i++) {
+ firsterr = torture_create_kthread(rcu_perf_reader, (void *)i,
+ reader_tasks[i]);
+ if (firsterr)
+ goto unwind;
+ }
+ while (atomic_read(&n_rcu_perf_reader_started) < nrealreaders)
+ schedule_timeout_uninterruptible(1);
+ writer_tasks = kcalloc(nrealwriters, sizeof(reader_tasks[0]),
+ GFP_KERNEL);
+ writer_durations = kcalloc(nrealwriters, sizeof(*writer_durations),
+ GFP_KERNEL);
+ writer_n_durations =
+ kcalloc(nrealwriters, sizeof(*writer_n_durations),
+ GFP_KERNEL);
+ if (!writer_tasks || !writer_durations || !writer_n_durations) {
+ VERBOSE_PERFOUT_ERRSTRING("out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ for (i = 0; i < nrealwriters; i++) {
+ writer_durations[i] =
+ kcalloc(MAX_MEAS, sizeof(*writer_durations[i]),
+ GFP_KERNEL);
+ if (!writer_durations[i])
+ goto unwind;
+ firsterr = torture_create_kthread(rcu_perf_writer, (void *)i,
+ writer_tasks[i]);
+ if (firsterr)
+ goto unwind;
+ }
+ torture_init_end();
+ return 0;
+
+unwind:
+ torture_init_end();
+ rcu_perf_cleanup();
+ return firsterr;
+}
+
+module_init(rcu_perf_init);
+module_exit(rcu_perf_cleanup);
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 250ea67c1615..084a28a732eb 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -130,8 +130,8 @@ static struct rcu_torture __rcu *rcu_torture_current;
static unsigned long rcu_torture_current_version;
static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
static DEFINE_SPINLOCK(rcu_torture_lock);
-static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = { 0 };
-static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = { 0 };
+static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count);
+static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch);
static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1];
static atomic_t n_rcu_torture_alloc;
static atomic_t n_rcu_torture_alloc_fail;
@@ -916,7 +916,7 @@ rcu_torture_fqs(void *arg)
static int
rcu_torture_writer(void *arg)
{
- bool can_expedite = !rcu_gp_is_expedited();
+ bool can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal();
int expediting = 0;
unsigned long gp_snap;
bool gp_cond1 = gp_cond, gp_exp1 = gp_exp, gp_normal1 = gp_normal;
@@ -932,7 +932,7 @@ rcu_torture_writer(void *arg)
VERBOSE_TOROUT_STRING("rcu_torture_writer task started");
if (!can_expedite) {
pr_alert("%s" TORTURE_FLAG
- " Grace periods expedited from boot/sysfs for %s,\n",
+ " GP expediting controlled from boot/sysfs for %s,\n",
torture_type, cur_ops->name);
pr_alert("%s" TORTURE_FLAG
" Disabled dynamic grace-period expediting.\n",
@@ -1082,17 +1082,6 @@ rcu_torture_fakewriter(void *arg)
return 0;
}
-static void rcutorture_trace_dump(void)
-{
- static atomic_t beenhere = ATOMIC_INIT(0);
-
- if (atomic_read(&beenhere))
- return;
- if (atomic_xchg(&beenhere, 1) != 0)
- return;
- ftrace_dump(DUMP_ALL);
-}
-
/*
* RCU torture reader from timer handler. Dereferences rcu_torture_current,
* incrementing the corresponding element of the pipeline array. The
@@ -1142,7 +1131,7 @@ static void rcu_torture_timer(unsigned long unused)
if (pipe_count > 1) {
do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts,
started, completed);
- rcutorture_trace_dump();
+ rcu_ftrace_dump(DUMP_ALL);
}
__this_cpu_inc(rcu_torture_count[pipe_count]);
completed = completed - started;
@@ -1215,7 +1204,7 @@ rcu_torture_reader(void *arg)
if (pipe_count > 1) {
do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu,
ts, started, completed);
- rcutorture_trace_dump();
+ rcu_ftrace_dump(DUMP_ALL);
}
__this_cpu_inc(rcu_torture_count[pipe_count]);
completed = completed - started;
@@ -1333,7 +1322,7 @@ rcu_torture_stats_print(void)
rcu_torture_writer_state,
gpnum, completed, flags);
show_rcu_gp_kthreads();
- rcutorture_trace_dump();
+ rcu_ftrace_dump(DUMP_ALL);
}
rtcv_snap = rcu_torture_current_version;
}
@@ -1489,7 +1478,9 @@ static int rcu_torture_barrier_cbs(void *arg)
* The above smp_load_acquire() ensures barrier_phase load
* is ordered before the folloiwng ->call().
*/
+ local_irq_disable(); /* Just to test no-irq call_rcu(). */
cur_ops->call(&rcu, rcu_torture_barrier_cbf);
+ local_irq_enable();
if (atomic_dec_and_test(&barrier_cbs_count))
wake_up(&barrier_wq);
} while (!torture_must_stop());
@@ -1596,7 +1587,7 @@ static int rcutorture_cpu_notify(struct notifier_block *self,
{
long cpu = (long)hcpu;
- switch (action) {
+ switch (action & ~CPU_TASKS_FROZEN) {
case CPU_ONLINE:
case CPU_DOWN_FAILED:
(void)rcutorture_booster_init(cpu);
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 9a535a86e732..c7f1bc4f817c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -102,6 +102,8 @@ struct rcu_state sname##_state = { \
.barrier_mutex = __MUTEX_INITIALIZER(sname##_state.barrier_mutex), \
.name = RCU_STATE_NAME(sname), \
.abbr = sabbr, \
+ .exp_mutex = __MUTEX_INITIALIZER(sname##_state.exp_mutex), \
+ .exp_wake_mutex = __MUTEX_INITIALIZER(sname##_state.exp_wake_mutex), \
}
RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched);
@@ -370,6 +372,21 @@ void rcu_all_qs(void)
rcu_momentary_dyntick_idle();
local_irq_restore(flags);
}
+ if (unlikely(raw_cpu_read(rcu_sched_data.cpu_no_qs.b.exp))) {
+ /*
+ * Yes, we just checked a per-CPU variable with preemption
+ * enabled, so we might be migrated to some other CPU at
+ * this point. That is OK because in that case, the
+ * migration will supply the needed quiescent state.
+ * We might end up needlessly disabling preemption and
+ * invoking rcu_sched_qs() on the destination CPU, but
+ * the probability and cost are both quite low, so this
+ * should not be a problem in practice.
+ */
+ preempt_disable();
+ rcu_sched_qs();
+ preempt_enable();
+ }
this_cpu_inc(rcu_qs_ctr);
barrier(); /* Avoid RCU read-side critical sections leaking up. */
}
@@ -385,9 +402,11 @@ module_param(qlowmark, long, 0444);
static ulong jiffies_till_first_fqs = ULONG_MAX;
static ulong jiffies_till_next_fqs = ULONG_MAX;
+static bool rcu_kick_kthreads;
module_param(jiffies_till_first_fqs, ulong, 0644);
module_param(jiffies_till_next_fqs, ulong, 0644);
+module_param(rcu_kick_kthreads, bool, 0644);
/*
* How long the grace period must be before we start recruiting
@@ -460,6 +479,28 @@ unsigned long rcu_batches_completed_bh(void)
EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
/*
+ * Return the number of RCU expedited batches completed thus far for
+ * debug & stats. Odd numbers mean that a batch is in progress, even
+ * numbers mean idle. The value returned will thus be roughly double
+ * the cumulative batches since boot.
+ */
+unsigned long rcu_exp_batches_completed(void)
+{
+ return rcu_state_p->expedited_sequence;
+}
+EXPORT_SYMBOL_GPL(rcu_exp_batches_completed);
+
+/*
+ * Return the number of RCU-sched expedited batches completed thus far
+ * for debug & stats. Similar to rcu_exp_batches_completed().
+ */
+unsigned long rcu_exp_batches_completed_sched(void)
+{
+ return rcu_sched_state.expedited_sequence;
+}
+EXPORT_SYMBOL_GPL(rcu_exp_batches_completed_sched);
+
+/*
* Force a quiescent state.
*/
void rcu_force_quiescent_state(void)
@@ -637,7 +678,7 @@ static void rcu_eqs_enter_common(long long oldval, bool user)
idle_task(smp_processor_id());
trace_rcu_dyntick(TPS("Error on entry: not idle task"), oldval, 0);
- ftrace_dump(DUMP_ORIG);
+ rcu_ftrace_dump(DUMP_ORIG);
WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s",
current->pid, current->comm,
idle->pid, idle->comm); /* must be idle task! */
@@ -799,7 +840,7 @@ static void rcu_eqs_exit_common(long long oldval, int user)
trace_rcu_dyntick(TPS("Error on exit: not idle task"),
oldval, rdtp->dynticks_nesting);
- ftrace_dump(DUMP_ORIG);
+ rcu_ftrace_dump(DUMP_ORIG);
WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s",
current->pid, current->comm,
idle->pid, idle->comm); /* must be idle task! */
@@ -1224,8 +1265,10 @@ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp)
rsp->gp_flags,
gp_state_getname(rsp->gp_state), rsp->gp_state,
rsp->gp_kthread ? rsp->gp_kthread->state : ~0);
- if (rsp->gp_kthread)
+ if (rsp->gp_kthread) {
sched_show_task(rsp->gp_kthread);
+ wake_up_process(rsp->gp_kthread);
+ }
}
}
@@ -1249,6 +1292,25 @@ static void rcu_dump_cpu_stacks(struct rcu_state *rsp)
}
}
+/*
+ * If too much time has passed in the current grace period, and if
+ * so configured, go kick the relevant kthreads.
+ */
+static void rcu_stall_kick_kthreads(struct rcu_state *rsp)
+{
+ unsigned long j;
+
+ if (!rcu_kick_kthreads)
+ return;
+ j = READ_ONCE(rsp->jiffies_kick_kthreads);
+ if (time_after(jiffies, j) && rsp->gp_kthread) {
+ WARN_ONCE(1, "Kicking %s grace-period kthread\n", rsp->name);
+ rcu_ftrace_dump(DUMP_ALL);
+ wake_up_process(rsp->gp_kthread);
+ WRITE_ONCE(rsp->jiffies_kick_kthreads, j + HZ);
+ }
+}
+
static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum)
{
int cpu;
@@ -1260,6 +1322,11 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum)
struct rcu_node *rnp = rcu_get_root(rsp);
long totqlen = 0;
+ /* Kick and suppress, if so configured. */
+ rcu_stall_kick_kthreads(rsp);
+ if (rcu_cpu_stall_suppress)
+ return;
+
/* Only let one CPU complain about others per time interval. */
raw_spin_lock_irqsave_rcu_node(rnp, flags);
@@ -1333,6 +1400,11 @@ static void print_cpu_stall(struct rcu_state *rsp)
struct rcu_node *rnp = rcu_get_root(rsp);
long totqlen = 0;
+ /* Kick and suppress, if so configured. */
+ rcu_stall_kick_kthreads(rsp);
+ if (rcu_cpu_stall_suppress)
+ return;
+
/*
* OK, time to rat on ourselves...
* See Documentation/RCU/stallwarn.txt for info on how to debug
@@ -1377,8 +1449,10 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
unsigned long js;
struct rcu_node *rnp;
- if (rcu_cpu_stall_suppress || !rcu_gp_in_progress(rsp))
+ if ((rcu_cpu_stall_suppress && !rcu_kick_kthreads) ||
+ !rcu_gp_in_progress(rsp))
return;
+ rcu_stall_kick_kthreads(rsp);
j = jiffies;
/*
@@ -2117,8 +2191,11 @@ static int __noreturn rcu_gp_kthread(void *arg)
}
ret = 0;
for (;;) {
- if (!ret)
+ if (!ret) {
rsp->jiffies_force_qs = jiffies + j;
+ WRITE_ONCE(rsp->jiffies_kick_kthreads,
+ jiffies + 3 * j);
+ }
trace_rcu_grace_period(rsp->name,
READ_ONCE(rsp->gpnum),
TPS("fqswait"));
@@ -2144,6 +2221,15 @@ static int __noreturn rcu_gp_kthread(void *arg)
TPS("fqsend"));
cond_resched_rcu_qs();
WRITE_ONCE(rsp->gp_activity, jiffies);
+ ret = 0; /* Force full wait till next FQS. */
+ j = jiffies_till_next_fqs;
+ if (j > HZ) {
+ j = HZ;
+ jiffies_till_next_fqs = HZ;
+ } else if (j < 1) {
+ j = 1;
+ jiffies_till_next_fqs = 1;
+ }
} else {
/* Deal with stray signal. */
cond_resched_rcu_qs();
@@ -2152,14 +2238,12 @@ static int __noreturn rcu_gp_kthread(void *arg)
trace_rcu_grace_period(rsp->name,
READ_ONCE(rsp->gpnum),
TPS("fqswaitsig"));
- }
- j = jiffies_till_next_fqs;
- if (j > HZ) {
- j = HZ;
- jiffies_till_next_fqs = HZ;
- } else if (j < 1) {
- j = 1;
- jiffies_till_next_fqs = 1;
+ ret = 1; /* Keep old FQS timing. */
+ j = jiffies;
+ if (time_after(jiffies, rsp->jiffies_force_qs))
+ j = 1;
+ else
+ j = rsp->jiffies_force_qs - j;
}
}
@@ -3376,8 +3460,12 @@ static void rcu_exp_gp_seq_end(struct rcu_state *rsp)
}
static unsigned long rcu_exp_gp_seq_snap(struct rcu_state *rsp)
{
+ unsigned long s;
+
smp_mb(); /* Caller's modifications seen first by other CPUs. */
- return rcu_seq_snap(&rsp->expedited_sequence);
+ s = rcu_seq_snap(&rsp->expedited_sequence);
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("snap"));
+ return s;
}
static bool rcu_exp_gp_seq_done(struct rcu_state *rsp, unsigned long s)
{
@@ -3469,7 +3557,7 @@ static void __maybe_unused sync_exp_reset_tree(struct rcu_state *rsp)
* for the current expedited grace period. Works only for preemptible
* RCU -- other RCU implementation use other means.
*
- * Caller must hold the root rcu_node's exp_funnel_mutex.
+ * Caller must hold the rcu_state's exp_mutex.
*/
static int sync_rcu_preempt_exp_done(struct rcu_node *rnp)
{
@@ -3485,8 +3573,8 @@ static int sync_rcu_preempt_exp_done(struct rcu_node *rnp)
* recursively up the tree. (Calm down, calm down, we do the recursion
* iteratively!)
*
- * Caller must hold the root rcu_node's exp_funnel_mutex and the
- * specified rcu_node structure's ->lock.
+ * Caller must hold the rcu_state's exp_mutex and the specified rcu_node
+ * structure's ->lock.
*/
static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
bool wake, unsigned long flags)
@@ -3523,7 +3611,7 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
* Report expedited quiescent state for specified node. This is a
* lock-acquisition wrapper function for __rcu_report_exp_rnp().
*
- * Caller must hold the root rcu_node's exp_funnel_mutex.
+ * Caller must hold the rcu_state's exp_mutex.
*/
static void __maybe_unused rcu_report_exp_rnp(struct rcu_state *rsp,
struct rcu_node *rnp, bool wake)
@@ -3536,8 +3624,8 @@ static void __maybe_unused rcu_report_exp_rnp(struct rcu_state *rsp,
/*
* Report expedited quiescent state for multiple CPUs, all covered by the
- * specified leaf rcu_node structure. Caller must hold the root
- * rcu_node's exp_funnel_mutex.
+ * specified leaf rcu_node structure. Caller must hold the rcu_state's
+ * exp_mutex.
*/
static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp,
unsigned long mask, bool wake)
@@ -3555,7 +3643,6 @@ static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp,
/*
* Report expedited quiescent state for specified rcu_data (CPU).
- * Caller must hold the root rcu_node's exp_funnel_mutex.
*/
static void rcu_report_exp_rdp(struct rcu_state *rsp, struct rcu_data *rdp,
bool wake)
@@ -3564,15 +3651,11 @@ static void rcu_report_exp_rdp(struct rcu_state *rsp, struct rcu_data *rdp,
}
/* Common code for synchronize_{rcu,sched}_expedited() work-done checking. */
-static bool sync_exp_work_done(struct rcu_state *rsp, struct rcu_node *rnp,
- struct rcu_data *rdp,
- atomic_long_t *stat, unsigned long s)
+static bool sync_exp_work_done(struct rcu_state *rsp, atomic_long_t *stat,
+ unsigned long s)
{
if (rcu_exp_gp_seq_done(rsp, s)) {
- if (rnp)
- mutex_unlock(&rnp->exp_funnel_mutex);
- else if (rdp)
- mutex_unlock(&rdp->exp_funnel_mutex);
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("done"));
/* Ensure test happens before caller kfree(). */
smp_mb__before_atomic(); /* ^^^ */
atomic_long_inc(stat);
@@ -3582,59 +3665,65 @@ static bool sync_exp_work_done(struct rcu_state *rsp, struct rcu_node *rnp,
}
/*
- * Funnel-lock acquisition for expedited grace periods. Returns a
- * pointer to the root rcu_node structure, or NULL if some other
- * task did the expedited grace period for us.
+ * Funnel-lock acquisition for expedited grace periods. Returns true
+ * if some other task completed an expedited grace period that this task
+ * can piggy-back on, and with no mutex held. Otherwise, returns false
+ * with the mutex held, indicating that the caller must actually do the
+ * expedited grace period.
*/
-static struct rcu_node *exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
+static bool exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
{
struct rcu_data *rdp = per_cpu_ptr(rsp->rda, raw_smp_processor_id());
- struct rcu_node *rnp0;
- struct rcu_node *rnp1 = NULL;
+ struct rcu_node *rnp = rdp->mynode;
+ struct rcu_node *rnp_root = rcu_get_root(rsp);
+
+ /* Low-contention fastpath. */
+ if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s) &&
+ (rnp == rnp_root ||
+ ULONG_CMP_LT(READ_ONCE(rnp_root->exp_seq_rq), s)) &&
+ !mutex_is_locked(&rsp->exp_mutex) &&
+ mutex_trylock(&rsp->exp_mutex))
+ goto fastpath;
/*
- * First try directly acquiring the root lock in order to reduce
- * latency in the common case where expedited grace periods are
- * rare. We check mutex_is_locked() to avoid pathological levels of
- * memory contention on ->exp_funnel_mutex in the heavy-load case.
+ * Each pass through the following loop works its way up
+ * the rcu_node tree, returning if others have done the work or
+ * otherwise falls through to acquire rsp->exp_mutex. The mapping
+ * from CPU to rcu_node structure can be inexact, as it is just
+ * promoting locality and is not strictly needed for correctness.
*/
- rnp0 = rcu_get_root(rsp);
- if (!mutex_is_locked(&rnp0->exp_funnel_mutex)) {
- if (mutex_trylock(&rnp0->exp_funnel_mutex)) {
- if (sync_exp_work_done(rsp, rnp0, NULL,
- &rdp->expedited_workdone0, s))
- return NULL;
- return rnp0;
+ for (; rnp != NULL; rnp = rnp->parent) {
+ if (sync_exp_work_done(rsp, &rdp->exp_workdone1, s))
+ return true;
+
+ /* Work not done, either wait here or go up. */
+ spin_lock(&rnp->exp_lock);
+ if (ULONG_CMP_GE(rnp->exp_seq_rq, s)) {
+
+ /* Someone else doing GP, so wait for them. */
+ spin_unlock(&rnp->exp_lock);
+ trace_rcu_exp_funnel_lock(rsp->name, rnp->level,
+ rnp->grplo, rnp->grphi,
+ TPS("wait"));
+ wait_event(rnp->exp_wq[(s >> 1) & 0x3],
+ sync_exp_work_done(rsp,
+ &rdp->exp_workdone2, s));
+ return true;
}
+ rnp->exp_seq_rq = s; /* Followers can wait on us. */
+ spin_unlock(&rnp->exp_lock);
+ trace_rcu_exp_funnel_lock(rsp->name, rnp->level, rnp->grplo,
+ rnp->grphi, TPS("nxtlvl"));
}
-
- /*
- * Each pass through the following loop works its way
- * up the rcu_node tree, returning if others have done the
- * work or otherwise falls through holding the root rnp's
- * ->exp_funnel_mutex. The mapping from CPU to rcu_node structure
- * can be inexact, as it is just promoting locality and is not
- * strictly needed for correctness.
- */
- if (sync_exp_work_done(rsp, NULL, NULL, &rdp->expedited_workdone1, s))
- return NULL;
- mutex_lock(&rdp->exp_funnel_mutex);
- rnp0 = rdp->mynode;
- for (; rnp0 != NULL; rnp0 = rnp0->parent) {
- if (sync_exp_work_done(rsp, rnp1, rdp,
- &rdp->expedited_workdone2, s))
- return NULL;
- mutex_lock(&rnp0->exp_funnel_mutex);
- if (rnp1)
- mutex_unlock(&rnp1->exp_funnel_mutex);
- else
- mutex_unlock(&rdp->exp_funnel_mutex);
- rnp1 = rnp0;
+ mutex_lock(&rsp->exp_mutex);
+fastpath:
+ if (sync_exp_work_done(rsp, &rdp->exp_workdone3, s)) {
+ mutex_unlock(&rsp->exp_mutex);
+ return true;
}
- if (sync_exp_work_done(rsp, rnp1, rdp,
- &rdp->expedited_workdone3, s))
- return NULL;
- return rnp1;
+ rcu_exp_gp_seq_start(rsp);
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
+ return false;
}
/* Invoked on each online non-idle CPU for expedited quiescent state. */
@@ -3649,6 +3738,11 @@ static void sync_sched_exp_handler(void *data)
if (!(READ_ONCE(rnp->expmask) & rdp->grpmask) ||
__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp))
return;
+ if (rcu_is_cpu_rrupt_from_idle()) {
+ rcu_report_exp_rdp(&rcu_sched_state,
+ this_cpu_ptr(&rcu_sched_data), true);
+ return;
+ }
__this_cpu_write(rcu_sched_data.cpu_no_qs.b.exp, true);
resched_cpu(smp_processor_id());
}
@@ -3773,7 +3867,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
rsp->name);
ndetected = 0;
rcu_for_each_leaf_node(rsp, rnp) {
- ndetected = rcu_print_task_exp_stall(rnp);
+ ndetected += rcu_print_task_exp_stall(rnp);
mask = 1;
for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask <<= 1) {
struct rcu_data *rdp;
@@ -3783,7 +3877,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
ndetected++;
rdp = per_cpu_ptr(rsp->rda, cpu);
pr_cont(" %d-%c%c%c", cpu,
- "O."[cpu_online(cpu)],
+ "O."[!!cpu_online(cpu)],
"o."[!!(rdp->grpmask & rnp->expmaskinit)],
"N."[!!(rdp->grpmask & rnp->expmaskinitnext)]);
}
@@ -3792,7 +3886,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
pr_cont(" } %lu jiffies s: %lu root: %#lx/%c\n",
jiffies - jiffies_start, rsp->expedited_sequence,
rnp_root->expmask, ".T"[!!rnp_root->exp_tasks]);
- if (!ndetected) {
+ if (ndetected) {
pr_err("blocking rcu_node structures:");
rcu_for_each_node_breadth_first(rsp, rnp) {
if (rnp == rnp_root)
@@ -3818,6 +3912,41 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
}
}
+/*
+ * Wait for the current expedited grace period to complete, and then
+ * wake up everyone who piggybacked on the just-completed expedited
+ * grace period. Also update all the ->exp_seq_rq counters as needed
+ * in order to avoid counter-wrap problems.
+ */
+static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
+{
+ struct rcu_node *rnp;
+
+ synchronize_sched_expedited_wait(rsp);
+ rcu_exp_gp_seq_end(rsp);
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("end"));
+
+ /*
+ * Switch over to wakeup mode, allowing the next GP, but -only- the
+ * next GP, to proceed.
+ */
+ mutex_lock(&rsp->exp_wake_mutex);
+ mutex_unlock(&rsp->exp_mutex);
+
+ rcu_for_each_node_breadth_first(rsp, rnp) {
+ if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s)) {
+ spin_lock(&rnp->exp_lock);
+ /* Recheck, avoid hang in case someone just arrived. */
+ if (ULONG_CMP_LT(rnp->exp_seq_rq, s))
+ rnp->exp_seq_rq = s;
+ spin_unlock(&rnp->exp_lock);
+ }
+ wake_up_all(&rnp->exp_wq[(rsp->expedited_sequence >> 1) & 0x3]);
+ }
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("endwake"));
+ mutex_unlock(&rsp->exp_wake_mutex);
+}
+
/**
* synchronize_sched_expedited - Brute-force RCU-sched grace period
*
@@ -3837,7 +3966,6 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
void synchronize_sched_expedited(void)
{
unsigned long s;
- struct rcu_node *rnp;
struct rcu_state *rsp = &rcu_sched_state;
/* If only one CPU, this is automatically a grace period. */
@@ -3852,17 +3980,14 @@ void synchronize_sched_expedited(void)
/* Take a snapshot of the sequence number. */
s = rcu_exp_gp_seq_snap(rsp);
-
- rnp = exp_funnel_lock(rsp, s);
- if (rnp == NULL)
+ if (exp_funnel_lock(rsp, s))
return; /* Someone else did our work for us. */
- rcu_exp_gp_seq_start(rsp);
+ /* Initialize the rcu_node tree in preparation for the wait. */
sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler);
- synchronize_sched_expedited_wait(rsp);
- rcu_exp_gp_seq_end(rsp);
- mutex_unlock(&rnp->exp_funnel_mutex);
+ /* Wait and clean up, including waking everyone. */
+ rcu_exp_wait_wake(rsp, s);
}
EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
@@ -4162,7 +4287,6 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp)
WARN_ON_ONCE(atomic_read(&rdp->dynticks->dynticks) != 1);
rdp->cpu = cpu;
rdp->rsp = rsp;
- mutex_init(&rdp->exp_funnel_mutex);
rcu_boot_init_nocb_percpu_data(rdp);
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
}
@@ -4420,10 +4544,8 @@ static void __init rcu_init_one(struct rcu_state *rsp)
{
static const char * const buf[] = RCU_NODE_NAME_INIT;
static const char * const fqs[] = RCU_FQS_NAME_INIT;
- static const char * const exp[] = RCU_EXP_NAME_INIT;
static struct lock_class_key rcu_node_class[RCU_NUM_LVLS];
static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS];
- static struct lock_class_key rcu_exp_class[RCU_NUM_LVLS];
static u8 fl_mask = 0x1;
int levelcnt[RCU_NUM_LVLS]; /* # nodes in each level. */
@@ -4482,9 +4604,11 @@ static void __init rcu_init_one(struct rcu_state *rsp)
rnp->level = i;
INIT_LIST_HEAD(&rnp->blkd_tasks);
rcu_init_one_nocb(rnp);
- mutex_init(&rnp->exp_funnel_mutex);
- lockdep_set_class_and_name(&rnp->exp_funnel_mutex,
- &rcu_exp_class[i], exp[i]);
+ init_waitqueue_head(&rnp->exp_wq[0]);
+ init_waitqueue_head(&rnp->exp_wq[1]);
+ init_waitqueue_head(&rnp->exp_wq[2]);
+ init_waitqueue_head(&rnp->exp_wq[3]);
+ spin_lock_init(&rnp->exp_lock);
}
}
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index df668c0f9e64..e3959f5e6ddf 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -70,7 +70,6 @@
# define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0 }
# define RCU_NODE_NAME_INIT { "rcu_node_0" }
# define RCU_FQS_NAME_INIT { "rcu_node_fqs_0" }
-# define RCU_EXP_NAME_INIT { "rcu_node_exp_0" }
#elif NR_CPUS <= RCU_FANOUT_2
# define RCU_NUM_LVLS 2
# define NUM_RCU_LVL_0 1
@@ -79,7 +78,6 @@
# define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0, NUM_RCU_LVL_1 }
# define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1" }
# define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1" }
-# define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1" }
#elif NR_CPUS <= RCU_FANOUT_3
# define RCU_NUM_LVLS 3
# define NUM_RCU_LVL_0 1
@@ -89,7 +87,6 @@
# define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0, NUM_RCU_LVL_1, NUM_RCU_LVL_2 }
# define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1", "rcu_node_2" }
# define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2" }
-# define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2" }
#elif NR_CPUS <= RCU_FANOUT_4
# define RCU_NUM_LVLS 4
# define NUM_RCU_LVL_0 1
@@ -100,7 +97,6 @@
# define NUM_RCU_LVL_INIT { NUM_RCU_LVL_0, NUM_RCU_LVL_1, NUM_RCU_LVL_2, NUM_RCU_LVL_3 }
# define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1", "rcu_node_2", "rcu_node_3" }
# define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2", "rcu_node_fqs_3" }
-# define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2", "rcu_node_exp_3" }
#else
# error "CONFIG_RCU_FANOUT insufficient for NR_CPUS"
#endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */
@@ -252,7 +248,9 @@ struct rcu_node {
/* Counts of upcoming no-CB GP requests. */
raw_spinlock_t fqslock ____cacheline_internodealigned_in_smp;
- struct mutex exp_funnel_mutex ____cacheline_internodealigned_in_smp;
+ spinlock_t exp_lock ____cacheline_internodealigned_in_smp;
+ unsigned long exp_seq_rq;
+ wait_queue_head_t exp_wq[4];
} ____cacheline_internodealigned_in_smp;
/*
@@ -387,11 +385,9 @@ struct rcu_data {
#ifdef CONFIG_RCU_FAST_NO_HZ
struct rcu_head oom_head;
#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
- struct mutex exp_funnel_mutex;
- atomic_long_t expedited_workdone0; /* # done by others #0. */
- atomic_long_t expedited_workdone1; /* # done by others #1. */
- atomic_long_t expedited_workdone2; /* # done by others #2. */
- atomic_long_t expedited_workdone3; /* # done by others #3. */
+ atomic_long_t exp_workdone1; /* # done by others #1. */
+ atomic_long_t exp_workdone2; /* # done by others #2. */
+ atomic_long_t exp_workdone3; /* # done by others #3. */
/* 7) Callback offloading. */
#ifdef CONFIG_RCU_NOCB_CPU
@@ -505,6 +501,8 @@ struct rcu_state {
/* _rcu_barrier(). */
/* End of fields guarded by barrier_mutex. */
+ struct mutex exp_mutex; /* Serialize expedited GP. */
+ struct mutex exp_wake_mutex; /* Serialize wakeup. */
unsigned long expedited_sequence; /* Take a ticket. */
atomic_long_t expedited_normal; /* # fallbacks to normal. */
atomic_t expedited_need_qs; /* # CPUs left to check in. */
@@ -513,6 +511,8 @@ struct rcu_state {
unsigned long jiffies_force_qs; /* Time at which to invoke */
/* force_quiescent_state(). */
+ unsigned long jiffies_kick_kthreads; /* Time at which to kick */
+ /* kthreads, if configured. */
unsigned long n_force_qs; /* Number of calls to */
/* force_quiescent_state(). */
unsigned long n_force_qs_lh; /* ~Number of calls leaving */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index efdf7b61ce12..ff1cd4e1188d 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -722,18 +722,22 @@ static void sync_rcu_exp_handler(void *info)
* synchronize_rcu_expedited - Brute-force RCU grace period
*
* Wait for an RCU-preempt grace period, but expedite it. The basic
- * idea is to invoke synchronize_sched_expedited() to push all the tasks to
- * the ->blkd_tasks lists and wait for this list to drain. This consumes
- * significant time on all CPUs and is unfriendly to real-time workloads,
- * so is thus not recommended for any sort of common-case code.
- * In fact, if you are using synchronize_rcu_expedited() in a loop,
- * please restructure your code to batch your updates, and then Use a
- * single synchronize_rcu() instead.
+ * idea is to IPI all non-idle non-nohz online CPUs. The IPI handler
+ * checks whether the CPU is in an RCU-preempt critical section, and
+ * if so, it sets a flag that causes the outermost rcu_read_unlock()
+ * to report the quiescent state. On the other hand, if the CPU is
+ * not in an RCU read-side critical section, the IPI handler reports
+ * the quiescent state immediately.
+ *
+ * Although this is a greate improvement over previous expedited
+ * implementations, it is still unfriendly to real-time workloads, so is
+ * thus not recommended for any sort of common-case code. In fact, if
+ * you are using synchronize_rcu_expedited() in a loop, please restructure
+ * your code to batch your updates, and then Use a single synchronize_rcu()
+ * instead.
*/
void synchronize_rcu_expedited(void)
{
- struct rcu_node *rnp;
- struct rcu_node *rnp_unlock;
struct rcu_state *rsp = rcu_state_p;
unsigned long s;
@@ -744,23 +748,14 @@ void synchronize_rcu_expedited(void)
}
s = rcu_exp_gp_seq_snap(rsp);
-
- rnp_unlock = exp_funnel_lock(rsp, s);
- if (rnp_unlock == NULL)
+ if (exp_funnel_lock(rsp, s))
return; /* Someone else did our work for us. */
- rcu_exp_gp_seq_start(rsp);
-
/* Initialize the rcu_node tree in preparation for the wait. */
sync_rcu_exp_select_cpus(rsp, sync_rcu_exp_handler);
- /* Wait for snapshotted ->blkd_tasks lists to drain. */
- rnp = rcu_get_root(rsp);
- synchronize_sched_expedited_wait(rsp);
-
- /* Clean up and exit. */
- rcu_exp_gp_seq_end(rsp);
- mutex_unlock(&rnp_unlock->exp_funnel_mutex);
+ /* Wait for ->blkd_tasks lists to drain, then wake everyone up. */
+ rcu_exp_wait_wake(rsp, s);
}
EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index 1088e64f01ad..86782f9a4604 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -185,17 +185,16 @@ static int show_rcuexp(struct seq_file *m, void *v)
int cpu;
struct rcu_state *rsp = (struct rcu_state *)m->private;
struct rcu_data *rdp;
- unsigned long s0 = 0, s1 = 0, s2 = 0, s3 = 0;
+ unsigned long s1 = 0, s2 = 0, s3 = 0;
for_each_possible_cpu(cpu) {
rdp = per_cpu_ptr(rsp->rda, cpu);
- s0 += atomic_long_read(&rdp->expedited_workdone0);
- s1 += atomic_long_read(&rdp->expedited_workdone1);
- s2 += atomic_long_read(&rdp->expedited_workdone2);
- s3 += atomic_long_read(&rdp->expedited_workdone3);
+ s1 += atomic_long_read(&rdp->exp_workdone1);
+ s2 += atomic_long_read(&rdp->exp_workdone2);
+ s3 += atomic_long_read(&rdp->exp_workdone3);
}
- seq_printf(m, "s=%lu wd0=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu enq=%d sc=%lu\n",
- rsp->expedited_sequence, s0, s1, s2, s3,
+ seq_printf(m, "s=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu enq=%d sc=%lu\n",
+ rsp->expedited_sequence, s1, s2, s3,
atomic_long_read(&rsp->expedited_normal),
atomic_read(&rsp->expedited_need_qs),
rsp->expedited_sequence / 2);
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index ca828b41c938..3ccdc8eebc5a 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -67,7 +67,7 @@ static int rcu_normal_after_boot;
module_param(rcu_normal_after_boot, int, 0);
#endif /* #ifndef CONFIG_TINY_RCU */
-#if defined(CONFIG_DEBUG_LOCK_ALLOC) && defined(CONFIG_PREEMPT_COUNT)
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
/**
* rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section?
*
@@ -111,7 +111,7 @@ int rcu_read_lock_sched_held(void)
return 0;
if (debug_locks)
lockdep_opinion = lock_is_held(&rcu_sched_lock_map);
- return lockdep_opinion || preempt_count() != 0 || irqs_disabled();
+ return lockdep_opinion || !preemptible();
}
EXPORT_SYMBOL(rcu_read_lock_sched_held);
#endif
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 414d9c16da42..5e59b832ae2b 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -24,3 +24,4 @@ obj-$(CONFIG_SCHEDSTATS) += stats.o
obj-$(CONFIG_SCHED_DEBUG) += debug.o
obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o
obj-$(CONFIG_CPU_FREQ) += cpufreq.o
+obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index fedb967a9841..e85a725e5c34 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -318,6 +318,7 @@ u64 sched_clock_cpu(int cpu)
return clock;
}
+EXPORT_SYMBOL_GPL(sched_clock_cpu);
void sched_clock_tick(void)
{
@@ -363,39 +364,6 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
}
EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
-/*
- * As outlined at the top, provides a fast, high resolution, nanosecond
- * time source that is monotonic per cpu argument and has bounded drift
- * between cpus.
- *
- * ######################### BIG FAT WARNING ##########################
- * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can #
- * # go backwards !! #
- * ####################################################################
- */
-u64 cpu_clock(int cpu)
-{
- if (!sched_clock_stable())
- return sched_clock_cpu(cpu);
-
- return sched_clock();
-}
-
-/*
- * Similar to cpu_clock() for the current cpu. Time will only be observed
- * to be monotonic if care is taken to only compare timestampt taken on the
- * same CPU.
- *
- * See cpu_clock().
- */
-u64 local_clock(void)
-{
- if (!sched_clock_stable())
- return sched_clock_cpu(raw_smp_processor_id());
-
- return sched_clock();
-}
-
#else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
void sched_clock_init(void)
@@ -410,22 +378,8 @@ u64 sched_clock_cpu(int cpu)
return sched_clock();
}
-
-u64 cpu_clock(int cpu)
-{
- return sched_clock();
-}
-
-u64 local_clock(void)
-{
- return sched_clock();
-}
-
#endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
-EXPORT_SYMBOL_GPL(cpu_clock);
-EXPORT_SYMBOL_GPL(local_clock);
-
/*
* Running clock - returns the time that has elapsed while a guest has been
* running.
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 8b489fcac37b..404c0784b1fc 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -33,7 +33,7 @@
#include <linux/init.h>
#include <linux/uaccess.h>
#include <linux/highmem.h>
-#include <asm/mmu_context.h>
+#include <linux/mmu_context.h>
#include <linux/interrupt.h>
#include <linux/capability.h>
#include <linux/completion.h>
@@ -170,6 +170,71 @@ static struct rq *this_rq_lock(void)
return rq;
}
+/*
+ * __task_rq_lock - lock the rq @p resides on.
+ */
+struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
+ __acquires(rq->lock)
+{
+ struct rq *rq;
+
+ lockdep_assert_held(&p->pi_lock);
+
+ for (;;) {
+ rq = task_rq(p);
+ raw_spin_lock(&rq->lock);
+ if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
+ rf->cookie = lockdep_pin_lock(&rq->lock);
+ return rq;
+ }
+ raw_spin_unlock(&rq->lock);
+
+ while (unlikely(task_on_rq_migrating(p)))
+ cpu_relax();
+ }
+}
+
+/*
+ * task_rq_lock - lock p->pi_lock and lock the rq @p resides on.
+ */
+struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
+ __acquires(p->pi_lock)
+ __acquires(rq->lock)
+{
+ struct rq *rq;
+
+ for (;;) {
+ raw_spin_lock_irqsave(&p->pi_lock, rf->flags);
+ rq = task_rq(p);
+ raw_spin_lock(&rq->lock);
+ /*
+ * move_queued_task() task_rq_lock()
+ *
+ * ACQUIRE (rq->lock)
+ * [S] ->on_rq = MIGRATING [L] rq = task_rq()
+ * WMB (__set_task_cpu()) ACQUIRE (rq->lock);
+ * [S] ->cpu = new_cpu [L] task_rq()
+ * [L] ->on_rq
+ * RELEASE (rq->lock)
+ *
+ * If we observe the old cpu in task_rq_lock, the acquire of
+ * the old rq->lock will fully serialize against the stores.
+ *
+ * If we observe the new cpu in task_rq_lock, the acquire will
+ * pair with the WMB to ensure we must then also see migrating.
+ */
+ if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
+ rf->cookie = lockdep_pin_lock(&rq->lock);
+ return rq;
+ }
+ raw_spin_unlock(&rq->lock);
+ raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
+
+ while (unlikely(task_on_rq_migrating(p)))
+ cpu_relax();
+ }
+}
+
#ifdef CONFIG_SCHED_HRTICK
/*
* Use HR-timers to deliver accurate preemption points.
@@ -249,29 +314,6 @@ void hrtick_start(struct rq *rq, u64 delay)
}
}
-static int
-hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu)
-{
- int cpu = (int)(long)hcpu;
-
- switch (action) {
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
- case CPU_DOWN_PREPARE:
- case CPU_DOWN_PREPARE_FROZEN:
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- hrtick_clear(cpu_rq(cpu));
- return NOTIFY_OK;
- }
-
- return NOTIFY_DONE;
-}
-
-static __init void init_hrtick(void)
-{
- hotcpu_notifier(hotplug_hrtick, 0);
-}
#else
/*
* Called to set the hrtick timer state.
@@ -288,10 +330,6 @@ void hrtick_start(struct rq *rq, u64 delay)
hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay),
HRTIMER_MODE_REL_PINNED);
}
-
-static inline void init_hrtick(void)
-{
-}
#endif /* CONFIG_SMP */
static void init_rq_hrtick(struct rq *rq)
@@ -315,10 +353,6 @@ static inline void hrtick_clear(struct rq *rq)
static inline void init_rq_hrtick(struct rq *rq)
{
}
-
-static inline void init_hrtick(void)
-{
-}
#endif /* CONFIG_SCHED_HRTICK */
/*
@@ -400,7 +434,7 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task)
* wakeup due to that.
*
* This cmpxchg() implies a full barrier, which pairs with the write
- * barrier implied by the wakeup in wake_up_list().
+ * barrier implied by the wakeup in wake_up_q().
*/
if (cmpxchg(&node->next, NULL, WAKE_Q_TAIL))
return;
@@ -499,7 +533,10 @@ int get_nohz_timer_target(void)
rcu_read_lock();
for_each_domain(cpu, sd) {
for_each_cpu(i, sched_domain_span(sd)) {
- if (!idle_cpu(i) && is_housekeeping_cpu(cpu)) {
+ if (cpu == i)
+ continue;
+
+ if (!idle_cpu(i) && is_housekeeping_cpu(i)) {
cpu = i;
goto unlock;
}
@@ -596,17 +633,8 @@ bool sched_can_stop_tick(struct rq *rq)
return false;
/*
- * FIFO realtime policy runs the highest priority task (after DEADLINE).
- * Other runnable tasks are of a lower priority. The scheduler tick
- * isn't needed.
- */
- fifo_nr_running = rq->rt.rt_nr_running - rq->rt.rr_nr_running;
- if (fifo_nr_running)
- return true;
-
- /*
- * Round-robin realtime tasks time slice with other tasks at the same
- * realtime priority.
+ * If there are more than one RR tasks, we need the tick to effect the
+ * actual RR behaviour.
*/
if (rq->rt.rr_nr_running) {
if (rq->rt.rr_nr_running == 1)
@@ -615,8 +643,20 @@ bool sched_can_stop_tick(struct rq *rq)
return false;
}
- /* Normal multitasking need periodic preemption checks */
- if (rq->cfs.nr_running > 1)
+ /*
+ * If there's no RR tasks, but FIFO tasks, we can skip the tick, no
+ * forced preemption between FIFO tasks.
+ */
+ fifo_nr_running = rq->rt.rt_nr_running - rq->rt.rr_nr_running;
+ if (fifo_nr_running)
+ return true;
+
+ /*
+ * If there are no DL,RR/FIFO tasks, there must only be CFS tasks left;
+ * if there's more than one we need the tick for involuntary
+ * preemption.
+ */
+ if (rq->nr_running > 1)
return false;
return true;
@@ -1082,12 +1122,20 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
static int __set_cpus_allowed_ptr(struct task_struct *p,
const struct cpumask *new_mask, bool check)
{
- unsigned long flags;
- struct rq *rq;
+ const struct cpumask *cpu_valid_mask = cpu_active_mask;
unsigned int dest_cpu;
+ struct rq_flags rf;
+ struct rq *rq;
int ret = 0;
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
+
+ if (p->flags & PF_KTHREAD) {
+ /*
+ * Kernel threads are allowed on online && !active CPUs
+ */
+ cpu_valid_mask = cpu_online_mask;
+ }
/*
* Must re-check here, to close a race against __kthread_bind(),
@@ -1101,22 +1149,32 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
if (cpumask_equal(&p->cpus_allowed, new_mask))
goto out;
- if (!cpumask_intersects(new_mask, cpu_active_mask)) {
+ if (!cpumask_intersects(new_mask, cpu_valid_mask)) {
ret = -EINVAL;
goto out;
}
do_set_cpus_allowed(p, new_mask);
+ if (p->flags & PF_KTHREAD) {
+ /*
+ * For kernel threads that do indeed end up on online &&
+ * !active we want to ensure they are strict per-cpu threads.
+ */
+ WARN_ON(cpumask_intersects(new_mask, cpu_online_mask) &&
+ !cpumask_intersects(new_mask, cpu_active_mask) &&
+ p->nr_cpus_allowed != 1);
+ }
+
/* Can the task run on the task's current CPU? If so, we're done */
if (cpumask_test_cpu(task_cpu(p), new_mask))
goto out;
- dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
+ dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask);
if (task_running(rq, p) || p->state == TASK_WAKING) {
struct migration_arg arg = { p, dest_cpu };
/* Need help from migration thread: drop lock and wait. */
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
tlb_migrate_finish(p->mm);
return 0;
@@ -1125,12 +1183,12 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
* OK, since we're going to drop the lock immediately
* afterwards anyway.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, rf.cookie);
rq = move_queued_task(rq, p, dest_cpu);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, rf.cookie);
}
out:
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return ret;
}
@@ -1314,8 +1372,8 @@ out:
*/
unsigned long wait_task_inactive(struct task_struct *p, long match_state)
{
- unsigned long flags;
int running, queued;
+ struct rq_flags rf;
unsigned long ncsw;
struct rq *rq;
@@ -1350,14 +1408,14 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
* lock now, to be *sure*. If we're wrong, we'll
* just go back and repeat.
*/
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
trace_sched_wait_task(p);
running = task_running(rq, p);
queued = task_on_rq_queued(p);
ncsw = 0;
if (!match_state || p->state == match_state)
ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
/*
* If it changed from the expected state, bail out now.
@@ -1431,6 +1489,25 @@ EXPORT_SYMBOL_GPL(kick_process);
/*
* ->cpus_allowed is protected by both rq->lock and p->pi_lock
+ *
+ * A few notes on cpu_active vs cpu_online:
+ *
+ * - cpu_active must be a subset of cpu_online
+ *
+ * - on cpu-up we allow per-cpu kthreads on the online && !active cpu,
+ * see __set_cpus_allowed_ptr(). At this point the newly online
+ * cpu isn't yet part of the sched domains, and balancing will not
+ * see it.
+ *
+ * - on cpu-down we clear cpu_active() to mask the sched domains and
+ * avoid the load balancer to place new tasks on the to be removed
+ * cpu. Existing tasks will remain running there and will be taken
+ * off.
+ *
+ * This means that fallback selection must not select !active CPUs.
+ * And can assume that any active CPU must be online. Conversely
+ * select_task_rq() below may allow selection of !active CPUs in order
+ * to satisfy the above rules.
*/
static int select_fallback_rq(int cpu, struct task_struct *p)
{
@@ -1449,8 +1526,6 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
/* Look for allowed, online CPU in same node. */
for_each_cpu(dest_cpu, nodemask) {
- if (!cpu_online(dest_cpu))
- continue;
if (!cpu_active(dest_cpu))
continue;
if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
@@ -1461,8 +1536,6 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
for (;;) {
/* Any allowed, online CPU? */
for_each_cpu(dest_cpu, tsk_cpus_allowed(p)) {
- if (!cpu_online(dest_cpu))
- continue;
if (!cpu_active(dest_cpu))
continue;
goto out;
@@ -1512,8 +1585,10 @@ int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
{
lockdep_assert_held(&p->pi_lock);
- if (p->nr_cpus_allowed > 1)
+ if (tsk_nr_cpus_allowed(p) > 1)
cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
+ else
+ cpu = cpumask_any(tsk_cpus_allowed(p));
/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -1601,8 +1676,8 @@ static inline void ttwu_activate(struct rq *rq, struct task_struct *p, int en_fl
/*
* Mark the task runnable and perform wakeup-preemption.
*/
-static void
-ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
+static void ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags,
+ struct pin_cookie cookie)
{
check_preempt_curr(rq, p, wake_flags);
p->state = TASK_RUNNING;
@@ -1614,9 +1689,9 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
* Our task @p is fully woken up and running; so its safe to
* drop the rq->lock, hereafter rq is only used for statistics.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
p->sched_class->task_woken(rq, p);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, cookie);
}
if (rq->idle_stamp) {
@@ -1634,17 +1709,23 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
}
static void
-ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags)
+ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags,
+ struct pin_cookie cookie)
{
+ int en_flags = ENQUEUE_WAKEUP;
+
lockdep_assert_held(&rq->lock);
#ifdef CONFIG_SMP
if (p->sched_contributes_to_load)
rq->nr_uninterruptible--;
+
+ if (wake_flags & WF_MIGRATED)
+ en_flags |= ENQUEUE_MIGRATED;
#endif
- ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING);
- ttwu_do_wakeup(rq, p, wake_flags);
+ ttwu_activate(rq, p, en_flags);
+ ttwu_do_wakeup(rq, p, wake_flags, cookie);
}
/*
@@ -1655,17 +1736,18 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags)
*/
static int ttwu_remote(struct task_struct *p, int wake_flags)
{
+ struct rq_flags rf;
struct rq *rq;
int ret = 0;
- rq = __task_rq_lock(p);
+ rq = __task_rq_lock(p, &rf);
if (task_on_rq_queued(p)) {
/* check_preempt_curr() may use rq clock */
update_rq_clock(rq);
- ttwu_do_wakeup(rq, p, wake_flags);
+ ttwu_do_wakeup(rq, p, wake_flags, rf.cookie);
ret = 1;
}
- __task_rq_unlock(rq);
+ __task_rq_unlock(rq, &rf);
return ret;
}
@@ -1675,6 +1757,7 @@ void sched_ttwu_pending(void)
{
struct rq *rq = this_rq();
struct llist_node *llist = llist_del_all(&rq->wake_list);
+ struct pin_cookie cookie;
struct task_struct *p;
unsigned long flags;
@@ -1682,15 +1765,19 @@ void sched_ttwu_pending(void)
return;
raw_spin_lock_irqsave(&rq->lock, flags);
- lockdep_pin_lock(&rq->lock);
+ cookie = lockdep_pin_lock(&rq->lock);
while (llist) {
p = llist_entry(llist, struct task_struct, wake_entry);
llist = llist_next(llist);
- ttwu_do_activate(rq, p, 0);
+ /*
+ * See ttwu_queue(); we only call ttwu_queue_remote() when
+ * its a x-cpu wakeup.
+ */
+ ttwu_do_activate(rq, p, WF_MIGRATED, cookie);
}
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
@@ -1774,9 +1861,10 @@ bool cpus_share_cache(int this_cpu, int that_cpu)
}
#endif /* CONFIG_SMP */
-static void ttwu_queue(struct task_struct *p, int cpu)
+static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags)
{
struct rq *rq = cpu_rq(cpu);
+ struct pin_cookie cookie;
#if defined(CONFIG_SMP)
if (sched_feat(TTWU_QUEUE) && !cpus_share_cache(smp_processor_id(), cpu)) {
@@ -1787,9 +1875,9 @@ static void ttwu_queue(struct task_struct *p, int cpu)
#endif
raw_spin_lock(&rq->lock);
- lockdep_pin_lock(&rq->lock);
- ttwu_do_activate(rq, p, 0);
- lockdep_unpin_lock(&rq->lock);
+ cookie = lockdep_pin_lock(&rq->lock);
+ ttwu_do_activate(rq, p, wake_flags, cookie);
+ lockdep_unpin_lock(&rq->lock, cookie);
raw_spin_unlock(&rq->lock);
}
@@ -1958,9 +2046,6 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
p->sched_contributes_to_load = !!task_contributes_to_load(p);
p->state = TASK_WAKING;
- if (p->sched_class->task_waking)
- p->sched_class->task_waking(p);
-
cpu = select_task_rq(p, p->wake_cpu, SD_BALANCE_WAKE, wake_flags);
if (task_cpu(p) != cpu) {
wake_flags |= WF_MIGRATED;
@@ -1968,7 +2053,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
}
#endif /* CONFIG_SMP */
- ttwu_queue(p, cpu);
+ ttwu_queue(p, cpu, wake_flags);
stat:
if (schedstat_enabled())
ttwu_stat(p, cpu, wake_flags);
@@ -1986,7 +2071,7 @@ out:
* ensure that this_rq() is locked, @p is bound to this_rq() and not
* the current task.
*/
-static void try_to_wake_up_local(struct task_struct *p)
+static void try_to_wake_up_local(struct task_struct *p, struct pin_cookie cookie)
{
struct rq *rq = task_rq(p);
@@ -2003,11 +2088,11 @@ static void try_to_wake_up_local(struct task_struct *p)
* disabled avoiding further scheduler activity on it and we've
* not yet picked a replacement task.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
raw_spin_unlock(&rq->lock);
raw_spin_lock(&p->pi_lock);
raw_spin_lock(&rq->lock);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, cookie);
}
if (!(p->state & TASK_NORMAL))
@@ -2018,7 +2103,7 @@ static void try_to_wake_up_local(struct task_struct *p)
if (!task_on_rq_queued(p))
ttwu_activate(rq, p, ENQUEUE_WAKEUP);
- ttwu_do_wakeup(rq, p, 0);
+ ttwu_do_wakeup(rq, p, 0, cookie);
if (schedstat_enabled())
ttwu_stat(p, smp_processor_id(), 0);
out:
@@ -2378,7 +2463,8 @@ static int dl_overflow(struct task_struct *p, int policy,
u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0;
int cpus, err = -1;
- if (new_bw == p->dl.dl_bw)
+ /* !deadline task may carry old deadline bandwidth */
+ if (new_bw == p->dl.dl_bw && task_has_dl_policy(p))
return 0;
/*
@@ -2417,12 +2503,12 @@ extern void init_dl_bw(struct dl_bw *dl_b);
*/
void wake_up_new_task(struct task_struct *p)
{
- unsigned long flags;
+ struct rq_flags rf;
struct rq *rq;
- raw_spin_lock_irqsave(&p->pi_lock, flags);
/* Initialize new task's runnable average */
init_entity_runnable_average(&p->se);
+ raw_spin_lock_irqsave(&p->pi_lock, rf.flags);
#ifdef CONFIG_SMP
/*
* Fork balancing, do it here and not earlier because:
@@ -2431,8 +2517,10 @@ void wake_up_new_task(struct task_struct *p)
*/
set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0));
#endif
+ /* Post initialize new task's util average when its cfs_rq is set */
+ post_init_entity_util_avg(&p->se);
- rq = __task_rq_lock(p);
+ rq = __task_rq_lock(p, &rf);
activate_task(rq, p, 0);
p->on_rq = TASK_ON_RQ_QUEUED;
trace_sched_wakeup_new(p);
@@ -2443,12 +2531,12 @@ void wake_up_new_task(struct task_struct *p)
* Nothing relies on rq->lock after this, so its fine to
* drop it.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, rf.cookie);
p->sched_class->task_woken(rq, p);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, rf.cookie);
}
#endif
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
}
#ifdef CONFIG_PREEMPT_NOTIFIERS
@@ -2710,7 +2798,7 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev)
*/
static __always_inline struct rq *
context_switch(struct rq *rq, struct task_struct *prev,
- struct task_struct *next)
+ struct task_struct *next, struct pin_cookie cookie)
{
struct mm_struct *mm, *oldmm;
@@ -2730,7 +2818,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
atomic_inc(&oldmm->mm_count);
enter_lazy_tlb(oldmm, next);
} else
- switch_mm(oldmm, mm, next);
+ switch_mm_irqs_off(oldmm, mm, next);
if (!prev->mm) {
prev->active_mm = NULL;
@@ -2742,7 +2830,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
* of the scheduler it's an obvious special-case), so we
* do an early lockdep release here:
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
/* Here we just switch the register state and the stack. */
@@ -2864,7 +2952,7 @@ EXPORT_PER_CPU_SYMBOL(kernel_cpustat);
*/
unsigned long long task_sched_runtime(struct task_struct *p)
{
- unsigned long flags;
+ struct rq_flags rf;
struct rq *rq;
u64 ns;
@@ -2884,7 +2972,7 @@ unsigned long long task_sched_runtime(struct task_struct *p)
return p->se.sum_exec_runtime;
#endif
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
/*
* Must be ->curr _and_ ->on_rq. If dequeued, we would
* project cycles that may never be accounted to this
@@ -2895,7 +2983,7 @@ unsigned long long task_sched_runtime(struct task_struct *p)
p->sched_class->update_curr(rq);
}
ns = p->se.sum_exec_runtime;
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return ns;
}
@@ -2915,7 +3003,7 @@ void scheduler_tick(void)
raw_spin_lock(&rq->lock);
update_rq_clock(rq);
curr->sched_class->task_tick(rq, curr, 0);
- update_cpu_load_active(rq);
+ cpu_load_update_active(rq);
calc_global_load_tick(rq);
raw_spin_unlock(&rq->lock);
@@ -2958,6 +3046,20 @@ u64 scheduler_tick_max_deferment(void)
#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
defined(CONFIG_PREEMPT_TRACER))
+/*
+ * If the value passed in is equal to the current preempt count
+ * then we just disabled preemption. Start timing the latency.
+ */
+static inline void preempt_latency_start(int val)
+{
+ if (preempt_count() == val) {
+ unsigned long ip = get_lock_parent_ip();
+#ifdef CONFIG_DEBUG_PREEMPT
+ current->preempt_disable_ip = ip;
+#endif
+ trace_preempt_off(CALLER_ADDR0, ip);
+ }
+}
void preempt_count_add(int val)
{
@@ -2976,17 +3078,21 @@ void preempt_count_add(int val)
DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
PREEMPT_MASK - 10);
#endif
- if (preempt_count() == val) {
- unsigned long ip = get_lock_parent_ip();
-#ifdef CONFIG_DEBUG_PREEMPT
- current->preempt_disable_ip = ip;
-#endif
- trace_preempt_off(CALLER_ADDR0, ip);
- }
+ preempt_latency_start(val);
}
EXPORT_SYMBOL(preempt_count_add);
NOKPROBE_SYMBOL(preempt_count_add);
+/*
+ * If the value passed in equals to the current preempt count
+ * then we just enabled preemption. Stop timing the latency.
+ */
+static inline void preempt_latency_stop(int val)
+{
+ if (preempt_count() == val)
+ trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
+}
+
void preempt_count_sub(int val)
{
#ifdef CONFIG_DEBUG_PREEMPT
@@ -3003,13 +3109,15 @@ void preempt_count_sub(int val)
return;
#endif
- if (preempt_count() == val)
- trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
+ preempt_latency_stop(val);
__preempt_count_sub(val);
}
EXPORT_SYMBOL(preempt_count_sub);
NOKPROBE_SYMBOL(preempt_count_sub);
+#else
+static inline void preempt_latency_start(int val) { }
+static inline void preempt_latency_stop(int val) { }
#endif
/*
@@ -3062,7 +3170,7 @@ static inline void schedule_debug(struct task_struct *prev)
* Pick up the highest-prio task:
*/
static inline struct task_struct *
-pick_next_task(struct rq *rq, struct task_struct *prev)
+pick_next_task(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie)
{
const struct sched_class *class = &fair_sched_class;
struct task_struct *p;
@@ -3073,20 +3181,20 @@ pick_next_task(struct rq *rq, struct task_struct *prev)
*/
if (likely(prev->sched_class == class &&
rq->nr_running == rq->cfs.h_nr_running)) {
- p = fair_sched_class.pick_next_task(rq, prev);
+ p = fair_sched_class.pick_next_task(rq, prev, cookie);
if (unlikely(p == RETRY_TASK))
goto again;
/* assumes fair_sched_class->next == idle_sched_class */
if (unlikely(!p))
- p = idle_sched_class.pick_next_task(rq, prev);
+ p = idle_sched_class.pick_next_task(rq, prev, cookie);
return p;
}
again:
for_each_class(class) {
- p = class->pick_next_task(rq, prev);
+ p = class->pick_next_task(rq, prev, cookie);
if (p) {
if (unlikely(p == RETRY_TASK))
goto again;
@@ -3140,6 +3248,7 @@ static void __sched notrace __schedule(bool preempt)
{
struct task_struct *prev, *next;
unsigned long *switch_count;
+ struct pin_cookie cookie;
struct rq *rq;
int cpu;
@@ -3173,7 +3282,7 @@ static void __sched notrace __schedule(bool preempt)
*/
smp_mb__before_spinlock();
raw_spin_lock(&rq->lock);
- lockdep_pin_lock(&rq->lock);
+ cookie = lockdep_pin_lock(&rq->lock);
rq->clock_skip_update <<= 1; /* promote REQ to ACT */
@@ -3195,7 +3304,7 @@ static void __sched notrace __schedule(bool preempt)
to_wakeup = wq_worker_sleeping(prev);
if (to_wakeup)
- try_to_wake_up_local(to_wakeup);
+ try_to_wake_up_local(to_wakeup, cookie);
}
}
switch_count = &prev->nvcsw;
@@ -3204,7 +3313,7 @@ static void __sched notrace __schedule(bool preempt)
if (task_on_rq_queued(prev))
update_rq_clock(rq);
- next = pick_next_task(rq, prev);
+ next = pick_next_task(rq, prev, cookie);
clear_tsk_need_resched(prev);
clear_preempt_need_resched();
rq->clock_skip_update = 0;
@@ -3215,9 +3324,9 @@ static void __sched notrace __schedule(bool preempt)
++*switch_count;
trace_sched_switch(preempt, prev, next);
- rq = context_switch(rq, prev, next); /* unlocks the rq */
+ rq = context_switch(rq, prev, next, cookie); /* unlocks the rq */
} else {
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
raw_spin_unlock_irq(&rq->lock);
}
@@ -3284,8 +3393,23 @@ void __sched schedule_preempt_disabled(void)
static void __sched notrace preempt_schedule_common(void)
{
do {
+ /*
+ * Because the function tracer can trace preempt_count_sub()
+ * and it also uses preempt_enable/disable_notrace(), if
+ * NEED_RESCHED is set, the preempt_enable_notrace() called
+ * by the function tracer will call this function again and
+ * cause infinite recursion.
+ *
+ * Preemption must be disabled here before the function
+ * tracer can trace. Break up preempt_disable() into two
+ * calls. One to disable preemption without fear of being
+ * traced. The other to still record the preemption latency,
+ * which can also be traced by the function tracer.
+ */
preempt_disable_notrace();
+ preempt_latency_start(1);
__schedule(true);
+ preempt_latency_stop(1);
preempt_enable_no_resched_notrace();
/*
@@ -3337,7 +3461,21 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
return;
do {
+ /*
+ * Because the function tracer can trace preempt_count_sub()
+ * and it also uses preempt_enable/disable_notrace(), if
+ * NEED_RESCHED is set, the preempt_enable_notrace() called
+ * by the function tracer will call this function again and
+ * cause infinite recursion.
+ *
+ * Preemption must be disabled here before the function
+ * tracer can trace. Break up preempt_disable() into two
+ * calls. One to disable preemption without fear of being
+ * traced. The other to still record the preemption latency,
+ * which can also be traced by the function tracer.
+ */
preempt_disable_notrace();
+ preempt_latency_start(1);
/*
* Needs preempt disabled in case user_exit() is traced
* and the tracer calls preempt_enable_notrace() causing
@@ -3347,6 +3485,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
__schedule(true);
exception_exit(prev_ctx);
+ preempt_latency_stop(1);
preempt_enable_no_resched_notrace();
} while (need_resched());
}
@@ -3403,12 +3542,13 @@ EXPORT_SYMBOL(default_wake_function);
void rt_mutex_setprio(struct task_struct *p, int prio)
{
int oldprio, queued, running, queue_flag = DEQUEUE_SAVE | DEQUEUE_MOVE;
- struct rq *rq;
const struct sched_class *prev_class;
+ struct rq_flags rf;
+ struct rq *rq;
BUG_ON(prio > MAX_PRIO);
- rq = __task_rq_lock(p);
+ rq = __task_rq_lock(p, &rf);
/*
* Idle task boosting is a nono in general. There is one
@@ -3484,7 +3624,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
check_class_changed(rq, p, prev_class, oldprio);
out_unlock:
preempt_disable(); /* avoid rq from going away on us */
- __task_rq_unlock(rq);
+ __task_rq_unlock(rq, &rf);
balance_callback(rq);
preempt_enable();
@@ -3494,7 +3634,7 @@ out_unlock:
void set_user_nice(struct task_struct *p, long nice)
{
int old_prio, delta, queued;
- unsigned long flags;
+ struct rq_flags rf;
struct rq *rq;
if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE)
@@ -3503,7 +3643,7 @@ void set_user_nice(struct task_struct *p, long nice)
* We have to be careful, if called from sys_setpriority(),
* the task might be in the middle of scheduling on another CPU.
*/
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
/*
* The RT priorities are set via sched_setscheduler(), but we still
* allow the 'normal' nice value to be set - but as expected
@@ -3534,7 +3674,7 @@ void set_user_nice(struct task_struct *p, long nice)
resched_curr(rq);
}
out_unlock:
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
}
EXPORT_SYMBOL(set_user_nice);
@@ -3831,11 +3971,11 @@ static int __sched_setscheduler(struct task_struct *p,
MAX_RT_PRIO - 1 - attr->sched_priority;
int retval, oldprio, oldpolicy = -1, queued, running;
int new_effective_prio, policy = attr->sched_policy;
- unsigned long flags;
const struct sched_class *prev_class;
- struct rq *rq;
+ struct rq_flags rf;
int reset_on_fork;
int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE;
+ struct rq *rq;
/* may grab non-irq protected spin_locks */
BUG_ON(in_interrupt());
@@ -3930,13 +4070,13 @@ recheck:
* To be able to change p->policy safely, the appropriate
* runqueue lock must be held.
*/
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
/*
* Changing the policy of the stop threads its a very bad idea
*/
if (p == rq->stop) {
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return -EINVAL;
}
@@ -3953,7 +4093,7 @@ recheck:
goto change;
p->sched_reset_on_fork = reset_on_fork;
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return 0;
}
change:
@@ -3967,7 +4107,7 @@ change:
if (rt_bandwidth_enabled() && rt_policy(policy) &&
task_group(p)->rt_bandwidth.rt_runtime == 0 &&
!task_group_is_autogroup(task_group(p))) {
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return -EPERM;
}
#endif
@@ -3982,7 +4122,7 @@ change:
*/
if (!cpumask_subset(span, &p->cpus_allowed) ||
rq->rd->dl_bw.bw == 0) {
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return -EPERM;
}
}
@@ -3992,7 +4132,7 @@ change:
/* recheck policy now with rq lock held */
if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
policy = oldpolicy = -1;
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
goto recheck;
}
@@ -4002,7 +4142,7 @@ change:
* is available.
*/
if ((dl_policy(policy) || dl_task(p)) && dl_overflow(p, policy, attr)) {
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
return -EBUSY;
}
@@ -4047,7 +4187,7 @@ change:
check_class_changed(rq, p, prev_class, oldprio);
preempt_disable(); /* avoid rq from going away on us */
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
if (pi)
rt_mutex_adjust_pi(p);
@@ -4900,10 +5040,10 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
{
struct task_struct *p;
unsigned int time_slice;
- unsigned long flags;
+ struct rq_flags rf;
+ struct timespec t;
struct rq *rq;
int retval;
- struct timespec t;
if (pid < 0)
return -EINVAL;
@@ -4918,11 +5058,11 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
if (retval)
goto out_unlock;
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
time_slice = 0;
if (p->sched_class->get_rr_interval)
time_slice = p->sched_class->get_rr_interval(rq, p);
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
rcu_read_unlock();
jiffies_to_timespec(time_slice, &t);
@@ -4998,7 +5138,8 @@ void show_state_filter(unsigned long state_filter)
touch_all_softlockup_watchdogs();
#ifdef CONFIG_SCHED_DEBUG
- sysrq_sched_debug_show();
+ if (!state_filter)
+ sysrq_sched_debug_show();
#endif
rcu_read_unlock();
/*
@@ -5160,6 +5301,8 @@ out:
#ifdef CONFIG_SMP
+static bool sched_smp_initialized __read_mostly;
+
#ifdef CONFIG_NUMA_BALANCING
/* Migrate current task p to target_cpu */
int migrate_task_to(struct task_struct *p, int target_cpu)
@@ -5185,11 +5328,11 @@ int migrate_task_to(struct task_struct *p, int target_cpu)
*/
void sched_setnuma(struct task_struct *p, int nid)
{
- struct rq *rq;
- unsigned long flags;
bool queued, running;
+ struct rq_flags rf;
+ struct rq *rq;
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
queued = task_on_rq_queued(p);
running = task_current(rq, p);
@@ -5204,7 +5347,7 @@ void sched_setnuma(struct task_struct *p, int nid)
p->sched_class->set_curr_task(rq);
if (queued)
enqueue_task(rq, p, ENQUEUE_RESTORE);
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
}
#endif /* CONFIG_NUMA_BALANCING */
@@ -5220,7 +5363,7 @@ void idle_task_exit(void)
BUG_ON(cpu_online(smp_processor_id()));
if (mm != &init_mm) {
- switch_mm(mm, &init_mm, current);
+ switch_mm_irqs_off(mm, &init_mm, current);
finish_arch_post_lock_switch();
}
mmdrop(mm);
@@ -5268,6 +5411,7 @@ static void migrate_tasks(struct rq *dead_rq)
{
struct rq *rq = dead_rq;
struct task_struct *next, *stop = rq->stop;
+ struct pin_cookie cookie;
int dest_cpu;
/*
@@ -5299,8 +5443,8 @@ static void migrate_tasks(struct rq *dead_rq)
/*
* pick_next_task assumes pinned rq->lock.
*/
- lockdep_pin_lock(&rq->lock);
- next = pick_next_task(rq, &fake_task);
+ cookie = lockdep_pin_lock(&rq->lock);
+ next = pick_next_task(rq, &fake_task, cookie);
BUG_ON(!next);
next->sched_class->put_prev_task(rq, next);
@@ -5313,7 +5457,7 @@ static void migrate_tasks(struct rq *dead_rq)
* because !cpu_active at this point, which means load-balance
* will not interfere. Also, stop-machine.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
raw_spin_unlock(&rq->lock);
raw_spin_lock(&next->pi_lock);
raw_spin_lock(&rq->lock);
@@ -5374,127 +5518,13 @@ static void set_rq_offline(struct rq *rq)
}
}
-/*
- * migration_call - callback that gets triggered when a CPU is added.
- * Here we can start up the necessary migration thread for the new CPU.
- */
-static int
-migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
+static void set_cpu_rq_start_time(unsigned int cpu)
{
- int cpu = (long)hcpu;
- unsigned long flags;
struct rq *rq = cpu_rq(cpu);
- switch (action & ~CPU_TASKS_FROZEN) {
-
- case CPU_UP_PREPARE:
- rq->calc_load_update = calc_load_update;
- account_reset_rq(rq);
- break;
-
- case CPU_ONLINE:
- /* Update our root-domain */
- raw_spin_lock_irqsave(&rq->lock, flags);
- if (rq->rd) {
- BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
-
- set_rq_online(rq);
- }
- raw_spin_unlock_irqrestore(&rq->lock, flags);
- break;
-
-#ifdef CONFIG_HOTPLUG_CPU
- case CPU_DYING:
- sched_ttwu_pending();
- /* Update our root-domain */
- raw_spin_lock_irqsave(&rq->lock, flags);
- if (rq->rd) {
- BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
- set_rq_offline(rq);
- }
- migrate_tasks(rq);
- BUG_ON(rq->nr_running != 1); /* the migration thread */
- raw_spin_unlock_irqrestore(&rq->lock, flags);
- break;
-
- case CPU_DEAD:
- calc_load_migrate(rq);
- break;
-#endif
- }
-
- update_max_interval();
-
- return NOTIFY_OK;
-}
-
-/*
- * Register at high priority so that task migration (migrate_all_tasks)
- * happens before everything else. This has to be lower priority than
- * the notifier in the perf_event subsystem, though.
- */
-static struct notifier_block migration_notifier = {
- .notifier_call = migration_call,
- .priority = CPU_PRI_MIGRATION,
-};
-
-static void set_cpu_rq_start_time(void)
-{
- int cpu = smp_processor_id();
- struct rq *rq = cpu_rq(cpu);
rq->age_stamp = sched_clock_cpu(cpu);
}
-static int sched_cpu_active(struct notifier_block *nfb,
- unsigned long action, void *hcpu)
-{
- int cpu = (long)hcpu;
-
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
- set_cpu_rq_start_time();
- return NOTIFY_OK;
-
- case CPU_DOWN_FAILED:
- set_cpu_active(cpu, true);
- return NOTIFY_OK;
-
- default:
- return NOTIFY_DONE;
- }
-}
-
-static int sched_cpu_inactive(struct notifier_block *nfb,
- unsigned long action, void *hcpu)
-{
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_DOWN_PREPARE:
- set_cpu_active((long)hcpu, false);
- return NOTIFY_OK;
- default:
- return NOTIFY_DONE;
- }
-}
-
-static int __init migration_init(void)
-{
- void *cpu = (void *)(long)smp_processor_id();
- int err;
-
- /* Initialize migration for the boot CPU */
- err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
- BUG_ON(err == NOTIFY_BAD);
- migration_call(&migration_notifier, CPU_ONLINE, cpu);
- register_cpu_notifier(&migration_notifier);
-
- /* Register cpu active notifiers */
- cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE);
- cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE);
-
- return 0;
-}
-early_initcall(migration_init);
-
static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */
#ifdef CONFIG_SCHED_DEBUG
@@ -6642,10 +6672,10 @@ static void sched_init_numa(void)
init_numa_topology_type();
}
-static void sched_domains_numa_masks_set(int cpu)
+static void sched_domains_numa_masks_set(unsigned int cpu)
{
- int i, j;
int node = cpu_to_node(cpu);
+ int i, j;
for (i = 0; i < sched_domains_numa_levels; i++) {
for (j = 0; j < nr_node_ids; j++) {
@@ -6655,51 +6685,20 @@ static void sched_domains_numa_masks_set(int cpu)
}
}
-static void sched_domains_numa_masks_clear(int cpu)
+static void sched_domains_numa_masks_clear(unsigned int cpu)
{
int i, j;
+
for (i = 0; i < sched_domains_numa_levels; i++) {
for (j = 0; j < nr_node_ids; j++)
cpumask_clear_cpu(cpu, sched_domains_numa_masks[i][j]);
}
}
-/*
- * Update sched_domains_numa_masks[level][node] array when new cpus
- * are onlined.
- */
-static int sched_domains_numa_masks_update(struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
-{
- int cpu = (long)hcpu;
-
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_ONLINE:
- sched_domains_numa_masks_set(cpu);
- break;
-
- case CPU_DEAD:
- sched_domains_numa_masks_clear(cpu);
- break;
-
- default:
- return NOTIFY_DONE;
- }
-
- return NOTIFY_OK;
-}
#else
-static inline void sched_init_numa(void)
-{
-}
-
-static int sched_domains_numa_masks_update(struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
-{
- return 0;
-}
+static inline void sched_init_numa(void) { }
+static void sched_domains_numa_masks_set(unsigned int cpu) { }
+static void sched_domains_numa_masks_clear(unsigned int cpu) { }
#endif /* CONFIG_NUMA */
static int __sdt_alloc(const struct cpumask *cpu_map)
@@ -7089,13 +7088,9 @@ static int num_cpus_frozen; /* used to mark begin/end of suspend/resume */
* If we come here as part of a suspend/resume, don't touch cpusets because we
* want to restore it back to its original state upon resume anyway.
*/
-static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
- void *hcpu)
+static void cpuset_cpu_active(void)
{
- switch (action) {
- case CPU_ONLINE_FROZEN:
- case CPU_DOWN_FAILED_FROZEN:
-
+ if (cpuhp_tasks_frozen) {
/*
* num_cpus_frozen tracks how many CPUs are involved in suspend
* resume sequence. As long as this is not the last online
@@ -7105,35 +7100,25 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
num_cpus_frozen--;
if (likely(num_cpus_frozen)) {
partition_sched_domains(1, NULL, NULL);
- break;
+ return;
}
-
/*
* This is the last CPU online operation. So fall through and
* restore the original sched domains by considering the
* cpuset configurations.
*/
-
- case CPU_ONLINE:
- cpuset_update_active_cpus(true);
- break;
- default:
- return NOTIFY_DONE;
}
- return NOTIFY_OK;
+ cpuset_update_active_cpus(true);
}
-static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
- void *hcpu)
+static int cpuset_cpu_inactive(unsigned int cpu)
{
unsigned long flags;
- long cpu = (long)hcpu;
struct dl_bw *dl_b;
bool overflow;
int cpus;
- switch (action) {
- case CPU_DOWN_PREPARE:
+ if (!cpuhp_tasks_frozen) {
rcu_read_lock_sched();
dl_b = dl_bw_of(cpu);
@@ -7145,18 +7130,119 @@ static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
rcu_read_unlock_sched();
if (overflow)
- return notifier_from_errno(-EBUSY);
+ return -EBUSY;
cpuset_update_active_cpus(false);
- break;
- case CPU_DOWN_PREPARE_FROZEN:
+ } else {
num_cpus_frozen++;
partition_sched_domains(1, NULL, NULL);
- break;
- default:
- return NOTIFY_DONE;
}
- return NOTIFY_OK;
+ return 0;
+}
+
+int sched_cpu_activate(unsigned int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ set_cpu_active(cpu, true);
+
+ if (sched_smp_initialized) {
+ sched_domains_numa_masks_set(cpu);
+ cpuset_cpu_active();
+ }
+
+ /*
+ * Put the rq online, if not already. This happens:
+ *
+ * 1) In the early boot process, because we build the real domains
+ * after all cpus have been brought up.
+ *
+ * 2) At runtime, if cpuset_cpu_active() fails to rebuild the
+ * domains.
+ */
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ if (rq->rd) {
+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+ set_rq_online(rq);
+ }
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+ update_max_interval();
+
+ return 0;
+}
+
+int sched_cpu_deactivate(unsigned int cpu)
+{
+ int ret;
+
+ set_cpu_active(cpu, false);
+ /*
+ * We've cleared cpu_active_mask, wait for all preempt-disabled and RCU
+ * users of this state to go away such that all new such users will
+ * observe it.
+ *
+ * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might
+ * not imply sync_sched(), so wait for both.
+ *
+ * Do sync before park smpboot threads to take care the rcu boost case.
+ */
+ if (IS_ENABLED(CONFIG_PREEMPT))
+ synchronize_rcu_mult(call_rcu, call_rcu_sched);
+ else
+ synchronize_rcu();
+
+ if (!sched_smp_initialized)
+ return 0;
+
+ ret = cpuset_cpu_inactive(cpu);
+ if (ret) {
+ set_cpu_active(cpu, true);
+ return ret;
+ }
+ sched_domains_numa_masks_clear(cpu);
+ return 0;
+}
+
+static void sched_rq_cpu_starting(unsigned int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+
+ rq->calc_load_update = calc_load_update;
+ account_reset_rq(rq);
+ update_max_interval();
+}
+
+int sched_cpu_starting(unsigned int cpu)
+{
+ set_cpu_rq_start_time(cpu);
+ sched_rq_cpu_starting(cpu);
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+int sched_cpu_dying(unsigned int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ /* Handle pending wakeups and then migrate everything off */
+ sched_ttwu_pending();
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ if (rq->rd) {
+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+ set_rq_offline(rq);
+ }
+ migrate_tasks(rq);
+ BUG_ON(rq->nr_running != 1);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+ calc_load_migrate(rq);
+ update_max_interval();
+ nohz_balance_exit_idle(cpu);
+ hrtick_clear(rq);
+ return 0;
}
+#endif
void __init sched_init_smp(void)
{
@@ -7179,12 +7265,6 @@ void __init sched_init_smp(void)
cpumask_set_cpu(smp_processor_id(), non_isolated_cpus);
mutex_unlock(&sched_domains_mutex);
- hotcpu_notifier(sched_domains_numa_masks_update, CPU_PRI_SCHED_ACTIVE);
- hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE);
- hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE);
-
- init_hrtick();
-
/* Move init over to a non-isolated CPU */
if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0)
BUG();
@@ -7193,7 +7273,16 @@ void __init sched_init_smp(void)
init_sched_rt_class();
init_sched_dl_class();
+ sched_smp_initialized = true;
+}
+
+static int __init migration_init(void)
+{
+ sched_rq_cpu_starting(smp_processor_id());
+ return 0;
}
+early_initcall(migration_init);
+
#else
void __init sched_init_smp(void)
{
@@ -7328,8 +7417,6 @@ void __init sched_init(void)
for (j = 0; j < CPU_LOAD_IDX_MAX; j++)
rq->cpu_load[j] = 0;
- rq->last_load_update_tick = jiffies;
-
#ifdef CONFIG_SMP
rq->sd = NULL;
rq->rd = NULL;
@@ -7348,12 +7435,13 @@ void __init sched_init(void)
rq_attach_root(rq, &def_root_domain);
#ifdef CONFIG_NO_HZ_COMMON
+ rq->last_load_update_tick = jiffies;
rq->nohz_flags = 0;
#endif
#ifdef CONFIG_NO_HZ_FULL
rq->last_sched_tick = 0;
#endif
-#endif
+#endif /* CONFIG_SMP */
init_rq_hrtick(rq);
atomic_set(&rq->nr_iowait, 0);
}
@@ -7391,7 +7479,7 @@ void __init sched_init(void)
if (cpu_isolated_map == NULL)
zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
idle_thread_set_boot_cpu();
- set_cpu_rq_start_time();
+ set_cpu_rq_start_time(smp_processor_id());
#endif
init_sched_fair_class();
@@ -7636,10 +7724,10 @@ void sched_move_task(struct task_struct *tsk)
{
struct task_group *tg;
int queued, running;
- unsigned long flags;
+ struct rq_flags rf;
struct rq *rq;
- rq = task_rq_lock(tsk, &flags);
+ rq = task_rq_lock(tsk, &rf);
running = task_current(rq, tsk);
queued = task_on_rq_queued(tsk);
@@ -7671,7 +7759,7 @@ void sched_move_task(struct task_struct *tsk)
if (queued)
enqueue_task(rq, tsk, ENQUEUE_RESTORE | ENQUEUE_MOVE);
- task_rq_unlock(rq, tsk, &flags);
+ task_rq_unlock(rq, tsk, &rf);
}
#endif /* CONFIG_CGROUP_SCHED */
@@ -7891,7 +7979,7 @@ static int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk)
static int sched_rt_global_constraints(void)
{
unsigned long flags;
- int i, ret = 0;
+ int i;
raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
for_each_possible_cpu(i) {
@@ -7903,7 +7991,7 @@ static int sched_rt_global_constraints(void)
}
raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags);
- return ret;
+ return 0;
}
#endif /* CONFIG_RT_GROUP_SCHED */
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 4a811203c04a..41f85c4d0938 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -25,11 +25,22 @@ enum cpuacct_stat_index {
CPUACCT_STAT_NSTATS,
};
+enum cpuacct_usage_index {
+ CPUACCT_USAGE_USER, /* ... user mode */
+ CPUACCT_USAGE_SYSTEM, /* ... kernel mode */
+
+ CPUACCT_USAGE_NRUSAGE,
+};
+
+struct cpuacct_usage {
+ u64 usages[CPUACCT_USAGE_NRUSAGE];
+};
+
/* track cpu usage of a group of tasks and its child groups */
struct cpuacct {
struct cgroup_subsys_state css;
/* cpuusage holds pointer to a u64-type object on every cpu */
- u64 __percpu *cpuusage;
+ struct cpuacct_usage __percpu *cpuusage;
struct kernel_cpustat __percpu *cpustat;
};
@@ -49,7 +60,7 @@ static inline struct cpuacct *parent_ca(struct cpuacct *ca)
return css_ca(ca->css.parent);
}
-static DEFINE_PER_CPU(u64, root_cpuacct_cpuusage);
+static DEFINE_PER_CPU(struct cpuacct_usage, root_cpuacct_cpuusage);
static struct cpuacct root_cpuacct = {
.cpustat = &kernel_cpustat,
.cpuusage = &root_cpuacct_cpuusage,
@@ -68,7 +79,7 @@ cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
if (!ca)
goto out;
- ca->cpuusage = alloc_percpu(u64);
+ ca->cpuusage = alloc_percpu(struct cpuacct_usage);
if (!ca->cpuusage)
goto out_free_ca;
@@ -96,20 +107,37 @@ static void cpuacct_css_free(struct cgroup_subsys_state *css)
kfree(ca);
}
-static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
+static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu,
+ enum cpuacct_usage_index index)
{
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
u64 data;
+ /*
+ * We allow index == CPUACCT_USAGE_NRUSAGE here to read
+ * the sum of suages.
+ */
+ BUG_ON(index > CPUACCT_USAGE_NRUSAGE);
+
#ifndef CONFIG_64BIT
/*
* Take rq->lock to make 64-bit read safe on 32-bit platforms.
*/
raw_spin_lock_irq(&cpu_rq(cpu)->lock);
- data = *cpuusage;
+#endif
+
+ if (index == CPUACCT_USAGE_NRUSAGE) {
+ int i = 0;
+
+ data = 0;
+ for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++)
+ data += cpuusage->usages[i];
+ } else {
+ data = cpuusage->usages[index];
+ }
+
+#ifndef CONFIG_64BIT
raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
-#else
- data = *cpuusage;
#endif
return data;
@@ -117,69 +145,103 @@ static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
{
- u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+ int i;
#ifndef CONFIG_64BIT
/*
* Take rq->lock to make 64-bit write safe on 32-bit platforms.
*/
raw_spin_lock_irq(&cpu_rq(cpu)->lock);
- *cpuusage = val;
+#endif
+
+ for (i = 0; i < CPUACCT_USAGE_NRUSAGE; i++)
+ cpuusage->usages[i] = val;
+
+#ifndef CONFIG_64BIT
raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
-#else
- *cpuusage = val;
#endif
}
/* return total cpu usage (in nanoseconds) of a group */
-static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
+static u64 __cpuusage_read(struct cgroup_subsys_state *css,
+ enum cpuacct_usage_index index)
{
struct cpuacct *ca = css_ca(css);
u64 totalcpuusage = 0;
int i;
- for_each_present_cpu(i)
- totalcpuusage += cpuacct_cpuusage_read(ca, i);
+ for_each_possible_cpu(i)
+ totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
return totalcpuusage;
}
+static u64 cpuusage_user_read(struct cgroup_subsys_state *css,
+ struct cftype *cft)
+{
+ return __cpuusage_read(css, CPUACCT_USAGE_USER);
+}
+
+static u64 cpuusage_sys_read(struct cgroup_subsys_state *css,
+ struct cftype *cft)
+{
+ return __cpuusage_read(css, CPUACCT_USAGE_SYSTEM);
+}
+
+static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
+{
+ return __cpuusage_read(css, CPUACCT_USAGE_NRUSAGE);
+}
+
static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
u64 val)
{
struct cpuacct *ca = css_ca(css);
- int err = 0;
- int i;
+ int cpu;
/*
* Only allow '0' here to do a reset.
*/
- if (val) {
- err = -EINVAL;
- goto out;
- }
+ if (val)
+ return -EINVAL;
- for_each_present_cpu(i)
- cpuacct_cpuusage_write(ca, i, 0);
+ for_each_possible_cpu(cpu)
+ cpuacct_cpuusage_write(ca, cpu, 0);
-out:
- return err;
+ return 0;
}
-static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
+static int __cpuacct_percpu_seq_show(struct seq_file *m,
+ enum cpuacct_usage_index index)
{
struct cpuacct *ca = css_ca(seq_css(m));
u64 percpu;
int i;
- for_each_present_cpu(i) {
- percpu = cpuacct_cpuusage_read(ca, i);
+ for_each_possible_cpu(i) {
+ percpu = cpuacct_cpuusage_read(ca, i, index);
seq_printf(m, "%llu ", (unsigned long long) percpu);
}
seq_printf(m, "\n");
return 0;
}
+static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V)
+{
+ return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_USER);
+}
+
+static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V)
+{
+ return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_SYSTEM);
+}
+
+static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
+{
+ return __cpuacct_percpu_seq_show(m, CPUACCT_USAGE_NRUSAGE);
+}
+
static const char * const cpuacct_stat_desc[] = {
[CPUACCT_STAT_USER] = "user",
[CPUACCT_STAT_SYSTEM] = "system",
@@ -191,7 +253,7 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v)
int cpu;
s64 val = 0;
- for_each_online_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
val += kcpustat->cpustat[CPUTIME_USER];
val += kcpustat->cpustat[CPUTIME_NICE];
@@ -200,7 +262,7 @@ static int cpuacct_stats_show(struct seq_file *sf, void *v)
seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val);
val = 0;
- for_each_online_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
val += kcpustat->cpustat[CPUTIME_SYSTEM];
val += kcpustat->cpustat[CPUTIME_IRQ];
@@ -220,10 +282,26 @@ static struct cftype files[] = {
.write_u64 = cpuusage_write,
},
{
+ .name = "usage_user",
+ .read_u64 = cpuusage_user_read,
+ },
+ {
+ .name = "usage_sys",
+ .read_u64 = cpuusage_sys_read,
+ },
+ {
.name = "usage_percpu",
.seq_show = cpuacct_percpu_seq_show,
},
{
+ .name = "usage_percpu_user",
+ .seq_show = cpuacct_percpu_user_seq_show,
+ },
+ {
+ .name = "usage_percpu_sys",
+ .seq_show = cpuacct_percpu_sys_seq_show,
+ },
+ {
.name = "stat",
.seq_show = cpuacct_stats_show,
},
@@ -238,10 +316,17 @@ static struct cftype files[] = {
void cpuacct_charge(struct task_struct *tsk, u64 cputime)
{
struct cpuacct *ca;
+ int index = CPUACCT_USAGE_SYSTEM;
+ struct pt_regs *regs = task_pt_regs(tsk);
+
+ if (regs && user_mode(regs))
+ index = CPUACCT_USAGE_USER;
rcu_read_lock();
+
for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
- *this_cpu_ptr(ca->cpuusage) += cputime;
+ this_cpu_ptr(ca->cpuusage)->usages[index] += cputime;
+
rcu_read_unlock();
}
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 5a75b08cfd85..5be58820465c 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -103,10 +103,10 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
const struct sched_dl_entity *dl_se = &p->dl;
if (later_mask &&
- cpumask_and(later_mask, cp->free_cpus, &p->cpus_allowed)) {
+ cpumask_and(later_mask, cp->free_cpus, tsk_cpus_allowed(p))) {
best_cpu = cpumask_any(later_mask);
goto out;
- } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) &&
+ } else if (cpumask_test_cpu(cpudl_maximum(cp), tsk_cpus_allowed(p)) &&
dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
best_cpu = cpudl_maximum(cp);
if (later_mask)
diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
index 928c4ba32f68..1141954e73b4 100644
--- a/kernel/sched/cpufreq.c
+++ b/kernel/sched/cpufreq.c
@@ -14,24 +14,50 @@
DEFINE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
/**
- * cpufreq_set_update_util_data - Populate the CPU's update_util_data pointer.
+ * cpufreq_add_update_util_hook - Populate the CPU's update_util_data pointer.
* @cpu: The CPU to set the pointer for.
* @data: New pointer value.
+ * @func: Callback function to set for the CPU.
*
- * Set and publish the update_util_data pointer for the given CPU. That pointer
- * points to a struct update_util_data object containing a callback function
- * to call from cpufreq_update_util(). That function will be called from an RCU
- * read-side critical section, so it must not sleep.
+ * Set and publish the update_util_data pointer for the given CPU.
*
- * Callers must use RCU-sched callbacks to free any memory that might be
- * accessed via the old update_util_data pointer or invoke synchronize_sched()
- * right after this function to avoid use-after-free.
+ * The update_util_data pointer of @cpu is set to @data and the callback
+ * function pointer in the target struct update_util_data is set to @func.
+ * That function will be called by cpufreq_update_util() from RCU-sched
+ * read-side critical sections, so it must not sleep. @data will always be
+ * passed to it as the first argument which allows the function to get to the
+ * target update_util_data structure and its container.
+ *
+ * The update_util_data pointer of @cpu must be NULL when this function is
+ * called or it will WARN() and return with no effect.
*/
-void cpufreq_set_update_util_data(int cpu, struct update_util_data *data)
+void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
+ void (*func)(struct update_util_data *data, u64 time,
+ unsigned long util, unsigned long max))
{
- if (WARN_ON(data && !data->func))
+ if (WARN_ON(!data || !func))
return;
+ if (WARN_ON(per_cpu(cpufreq_update_util_data, cpu)))
+ return;
+
+ data->func = func;
rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), data);
}
-EXPORT_SYMBOL_GPL(cpufreq_set_update_util_data);
+EXPORT_SYMBOL_GPL(cpufreq_add_update_util_hook);
+
+/**
+ * cpufreq_remove_update_util_hook - Clear the CPU's update_util_data pointer.
+ * @cpu: The CPU to clear the pointer for.
+ *
+ * Clear the update_util_data pointer for the given CPU.
+ *
+ * Callers must use RCU-sched callbacks to free any memory that might be
+ * accessed via the old update_util_data pointer or invoke synchronize_sched()
+ * right after this function to avoid use-after-free.
+ */
+void cpufreq_remove_update_util_hook(int cpu)
+{
+ rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL);
+}
+EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook);
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
new file mode 100644
index 000000000000..154ae3a51e86
--- /dev/null
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -0,0 +1,530 @@
+/*
+ * CPUFreq governor based on scheduler-provided CPU utilization data.
+ *
+ * Copyright (C) 2016, Intel Corporation
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <trace/events/power.h>
+
+#include "sched.h"
+
+struct sugov_tunables {
+ struct gov_attr_set attr_set;
+ unsigned int rate_limit_us;
+};
+
+struct sugov_policy {
+ struct cpufreq_policy *policy;
+
+ struct sugov_tunables *tunables;
+ struct list_head tunables_hook;
+
+ raw_spinlock_t update_lock; /* For shared policies */
+ u64 last_freq_update_time;
+ s64 freq_update_delay_ns;
+ unsigned int next_freq;
+
+ /* The next fields are only needed if fast switch cannot be used. */
+ struct irq_work irq_work;
+ struct work_struct work;
+ struct mutex work_lock;
+ bool work_in_progress;
+
+ bool need_freq_update;
+};
+
+struct sugov_cpu {
+ struct update_util_data update_util;
+ struct sugov_policy *sg_policy;
+
+ /* The fields below are only needed when sharing a policy. */
+ unsigned long util;
+ unsigned long max;
+ u64 last_update;
+};
+
+static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu);
+
+/************************ Governor internals ***********************/
+
+static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time)
+{
+ s64 delta_ns;
+
+ if (sg_policy->work_in_progress)
+ return false;
+
+ if (unlikely(sg_policy->need_freq_update)) {
+ sg_policy->need_freq_update = false;
+ /*
+ * This happens when limits change, so forget the previous
+ * next_freq value and force an update.
+ */
+ sg_policy->next_freq = UINT_MAX;
+ return true;
+ }
+
+ delta_ns = time - sg_policy->last_freq_update_time;
+ return delta_ns >= sg_policy->freq_update_delay_ns;
+}
+
+static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time,
+ unsigned int next_freq)
+{
+ struct cpufreq_policy *policy = sg_policy->policy;
+
+ sg_policy->last_freq_update_time = time;
+
+ if (policy->fast_switch_enabled) {
+ if (sg_policy->next_freq == next_freq) {
+ trace_cpu_frequency(policy->cur, smp_processor_id());
+ return;
+ }
+ sg_policy->next_freq = next_freq;
+ next_freq = cpufreq_driver_fast_switch(policy, next_freq);
+ if (next_freq == CPUFREQ_ENTRY_INVALID)
+ return;
+
+ policy->cur = next_freq;
+ trace_cpu_frequency(next_freq, smp_processor_id());
+ } else if (sg_policy->next_freq != next_freq) {
+ sg_policy->next_freq = next_freq;
+ sg_policy->work_in_progress = true;
+ irq_work_queue(&sg_policy->irq_work);
+ }
+}
+
+/**
+ * get_next_freq - Compute a new frequency for a given cpufreq policy.
+ * @policy: cpufreq policy object to compute the new frequency for.
+ * @util: Current CPU utilization.
+ * @max: CPU capacity.
+ *
+ * If the utilization is frequency-invariant, choose the new frequency to be
+ * proportional to it, that is
+ *
+ * next_freq = C * max_freq * util / max
+ *
+ * Otherwise, approximate the would-be frequency-invariant utilization by
+ * util_raw * (curr_freq / max_freq) which leads to
+ *
+ * next_freq = C * curr_freq * util_raw / max
+ *
+ * Take C = 1.25 for the frequency tipping point at (util / max) = 0.8.
+ */
+static unsigned int get_next_freq(struct cpufreq_policy *policy,
+ unsigned long util, unsigned long max)
+{
+ unsigned int freq = arch_scale_freq_invariant() ?
+ policy->cpuinfo.max_freq : policy->cur;
+
+ return (freq + (freq >> 2)) * util / max;
+}
+
+static void sugov_update_single(struct update_util_data *hook, u64 time,
+ unsigned long util, unsigned long max)
+{
+ struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
+ struct sugov_policy *sg_policy = sg_cpu->sg_policy;
+ struct cpufreq_policy *policy = sg_policy->policy;
+ unsigned int next_f;
+
+ if (!sugov_should_update_freq(sg_policy, time))
+ return;
+
+ next_f = util == ULONG_MAX ? policy->cpuinfo.max_freq :
+ get_next_freq(policy, util, max);
+ sugov_update_commit(sg_policy, time, next_f);
+}
+
+static unsigned int sugov_next_freq_shared(struct sugov_policy *sg_policy,
+ unsigned long util, unsigned long max)
+{
+ struct cpufreq_policy *policy = sg_policy->policy;
+ unsigned int max_f = policy->cpuinfo.max_freq;
+ u64 last_freq_update_time = sg_policy->last_freq_update_time;
+ unsigned int j;
+
+ if (util == ULONG_MAX)
+ return max_f;
+
+ for_each_cpu(j, policy->cpus) {
+ struct sugov_cpu *j_sg_cpu;
+ unsigned long j_util, j_max;
+ s64 delta_ns;
+
+ if (j == smp_processor_id())
+ continue;
+
+ j_sg_cpu = &per_cpu(sugov_cpu, j);
+ /*
+ * If the CPU utilization was last updated before the previous
+ * frequency update and the time elapsed between the last update
+ * of the CPU utilization and the last frequency update is long
+ * enough, don't take the CPU into account as it probably is
+ * idle now.
+ */
+ delta_ns = last_freq_update_time - j_sg_cpu->last_update;
+ if (delta_ns > TICK_NSEC)
+ continue;
+
+ j_util = j_sg_cpu->util;
+ if (j_util == ULONG_MAX)
+ return max_f;
+
+ j_max = j_sg_cpu->max;
+ if (j_util * max > j_max * util) {
+ util = j_util;
+ max = j_max;
+ }
+ }
+
+ return get_next_freq(policy, util, max);
+}
+
+static void sugov_update_shared(struct update_util_data *hook, u64 time,
+ unsigned long util, unsigned long max)
+{
+ struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
+ struct sugov_policy *sg_policy = sg_cpu->sg_policy;
+ unsigned int next_f;
+
+ raw_spin_lock(&sg_policy->update_lock);
+
+ sg_cpu->util = util;
+ sg_cpu->max = max;
+ sg_cpu->last_update = time;
+
+ if (sugov_should_update_freq(sg_policy, time)) {
+ next_f = sugov_next_freq_shared(sg_policy, util, max);
+ sugov_update_commit(sg_policy, time, next_f);
+ }
+
+ raw_spin_unlock(&sg_policy->update_lock);
+}
+
+static void sugov_work(struct work_struct *work)
+{
+ struct sugov_policy *sg_policy = container_of(work, struct sugov_policy, work);
+
+ mutex_lock(&sg_policy->work_lock);
+ __cpufreq_driver_target(sg_policy->policy, sg_policy->next_freq,
+ CPUFREQ_RELATION_L);
+ mutex_unlock(&sg_policy->work_lock);
+
+ sg_policy->work_in_progress = false;
+}
+
+static void sugov_irq_work(struct irq_work *irq_work)
+{
+ struct sugov_policy *sg_policy;
+
+ sg_policy = container_of(irq_work, struct sugov_policy, irq_work);
+ schedule_work_on(smp_processor_id(), &sg_policy->work);
+}
+
+/************************** sysfs interface ************************/
+
+static struct sugov_tunables *global_tunables;
+static DEFINE_MUTEX(global_tunables_lock);
+
+static inline struct sugov_tunables *to_sugov_tunables(struct gov_attr_set *attr_set)
+{
+ return container_of(attr_set, struct sugov_tunables, attr_set);
+}
+
+static ssize_t rate_limit_us_show(struct gov_attr_set *attr_set, char *buf)
+{
+ struct sugov_tunables *tunables = to_sugov_tunables(attr_set);
+
+ return sprintf(buf, "%u\n", tunables->rate_limit_us);
+}
+
+static ssize_t rate_limit_us_store(struct gov_attr_set *attr_set, const char *buf,
+ size_t count)
+{
+ struct sugov_tunables *tunables = to_sugov_tunables(attr_set);
+ struct sugov_policy *sg_policy;
+ unsigned int rate_limit_us;
+
+ if (kstrtouint(buf, 10, &rate_limit_us))
+ return -EINVAL;
+
+ tunables->rate_limit_us = rate_limit_us;
+
+ list_for_each_entry(sg_policy, &attr_set->policy_list, tunables_hook)
+ sg_policy->freq_update_delay_ns = rate_limit_us * NSEC_PER_USEC;
+
+ return count;
+}
+
+static struct governor_attr rate_limit_us = __ATTR_RW(rate_limit_us);
+
+static struct attribute *sugov_attributes[] = {
+ &rate_limit_us.attr,
+ NULL
+};
+
+static struct kobj_type sugov_tunables_ktype = {
+ .default_attrs = sugov_attributes,
+ .sysfs_ops = &governor_sysfs_ops,
+};
+
+/********************** cpufreq governor interface *********************/
+
+static struct cpufreq_governor schedutil_gov;
+
+static struct sugov_policy *sugov_policy_alloc(struct cpufreq_policy *policy)
+{
+ struct sugov_policy *sg_policy;
+
+ sg_policy = kzalloc(sizeof(*sg_policy), GFP_KERNEL);
+ if (!sg_policy)
+ return NULL;
+
+ sg_policy->policy = policy;
+ init_irq_work(&sg_policy->irq_work, sugov_irq_work);
+ INIT_WORK(&sg_policy->work, sugov_work);
+ mutex_init(&sg_policy->work_lock);
+ raw_spin_lock_init(&sg_policy->update_lock);
+ return sg_policy;
+}
+
+static void sugov_policy_free(struct sugov_policy *sg_policy)
+{
+ mutex_destroy(&sg_policy->work_lock);
+ kfree(sg_policy);
+}
+
+static struct sugov_tunables *sugov_tunables_alloc(struct sugov_policy *sg_policy)
+{
+ struct sugov_tunables *tunables;
+
+ tunables = kzalloc(sizeof(*tunables), GFP_KERNEL);
+ if (tunables) {
+ gov_attr_set_init(&tunables->attr_set, &sg_policy->tunables_hook);
+ if (!have_governor_per_policy())
+ global_tunables = tunables;
+ }
+ return tunables;
+}
+
+static void sugov_tunables_free(struct sugov_tunables *tunables)
+{
+ if (!have_governor_per_policy())
+ global_tunables = NULL;
+
+ kfree(tunables);
+}
+
+static int sugov_init(struct cpufreq_policy *policy)
+{
+ struct sugov_policy *sg_policy;
+ struct sugov_tunables *tunables;
+ unsigned int lat;
+ int ret = 0;
+
+ /* State should be equivalent to EXIT */
+ if (policy->governor_data)
+ return -EBUSY;
+
+ sg_policy = sugov_policy_alloc(policy);
+ if (!sg_policy)
+ return -ENOMEM;
+
+ mutex_lock(&global_tunables_lock);
+
+ if (global_tunables) {
+ if (WARN_ON(have_governor_per_policy())) {
+ ret = -EINVAL;
+ goto free_sg_policy;
+ }
+ policy->governor_data = sg_policy;
+ sg_policy->tunables = global_tunables;
+
+ gov_attr_set_get(&global_tunables->attr_set, &sg_policy->tunables_hook);
+ goto out;
+ }
+
+ tunables = sugov_tunables_alloc(sg_policy);
+ if (!tunables) {
+ ret = -ENOMEM;
+ goto free_sg_policy;
+ }
+
+ tunables->rate_limit_us = LATENCY_MULTIPLIER;
+ lat = policy->cpuinfo.transition_latency / NSEC_PER_USEC;
+ if (lat)
+ tunables->rate_limit_us *= lat;
+
+ policy->governor_data = sg_policy;
+ sg_policy->tunables = tunables;
+
+ ret = kobject_init_and_add(&tunables->attr_set.kobj, &sugov_tunables_ktype,
+ get_governor_parent_kobj(policy), "%s",
+ schedutil_gov.name);
+ if (ret)
+ goto fail;
+
+ out:
+ mutex_unlock(&global_tunables_lock);
+
+ cpufreq_enable_fast_switch(policy);
+ return 0;
+
+ fail:
+ policy->governor_data = NULL;
+ sugov_tunables_free(tunables);
+
+ free_sg_policy:
+ mutex_unlock(&global_tunables_lock);
+
+ sugov_policy_free(sg_policy);
+ pr_err("cpufreq: schedutil governor initialization failed (error %d)\n", ret);
+ return ret;
+}
+
+static int sugov_exit(struct cpufreq_policy *policy)
+{
+ struct sugov_policy *sg_policy = policy->governor_data;
+ struct sugov_tunables *tunables = sg_policy->tunables;
+ unsigned int count;
+
+ cpufreq_disable_fast_switch(policy);
+
+ mutex_lock(&global_tunables_lock);
+
+ count = gov_attr_set_put(&tunables->attr_set, &sg_policy->tunables_hook);
+ policy->governor_data = NULL;
+ if (!count)
+ sugov_tunables_free(tunables);
+
+ mutex_unlock(&global_tunables_lock);
+
+ sugov_policy_free(sg_policy);
+ return 0;
+}
+
+static int sugov_start(struct cpufreq_policy *policy)
+{
+ struct sugov_policy *sg_policy = policy->governor_data;
+ unsigned int cpu;
+
+ sg_policy->freq_update_delay_ns = sg_policy->tunables->rate_limit_us * NSEC_PER_USEC;
+ sg_policy->last_freq_update_time = 0;
+ sg_policy->next_freq = UINT_MAX;
+ sg_policy->work_in_progress = false;
+ sg_policy->need_freq_update = false;
+
+ for_each_cpu(cpu, policy->cpus) {
+ struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu);
+
+ sg_cpu->sg_policy = sg_policy;
+ if (policy_is_shared(policy)) {
+ sg_cpu->util = ULONG_MAX;
+ sg_cpu->max = 0;
+ sg_cpu->last_update = 0;
+ cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util,
+ sugov_update_shared);
+ } else {
+ cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util,
+ sugov_update_single);
+ }
+ }
+ return 0;
+}
+
+static int sugov_stop(struct cpufreq_policy *policy)
+{
+ struct sugov_policy *sg_policy = policy->governor_data;
+ unsigned int cpu;
+
+ for_each_cpu(cpu, policy->cpus)
+ cpufreq_remove_update_util_hook(cpu);
+
+ synchronize_sched();
+
+ irq_work_sync(&sg_policy->irq_work);
+ cancel_work_sync(&sg_policy->work);
+ return 0;
+}
+
+static int sugov_limits(struct cpufreq_policy *policy)
+{
+ struct sugov_policy *sg_policy = policy->governor_data;
+
+ if (!policy->fast_switch_enabled) {
+ mutex_lock(&sg_policy->work_lock);
+
+ if (policy->max < policy->cur)
+ __cpufreq_driver_target(policy, policy->max,
+ CPUFREQ_RELATION_H);
+ else if (policy->min > policy->cur)
+ __cpufreq_driver_target(policy, policy->min,
+ CPUFREQ_RELATION_L);
+
+ mutex_unlock(&sg_policy->work_lock);
+ }
+
+ sg_policy->need_freq_update = true;
+ return 0;
+}
+
+int sugov_governor(struct cpufreq_policy *policy, unsigned int event)
+{
+ if (event == CPUFREQ_GOV_POLICY_INIT) {
+ return sugov_init(policy);
+ } else if (policy->governor_data) {
+ switch (event) {
+ case CPUFREQ_GOV_POLICY_EXIT:
+ return sugov_exit(policy);
+ case CPUFREQ_GOV_START:
+ return sugov_start(policy);
+ case CPUFREQ_GOV_STOP:
+ return sugov_stop(policy);
+ case CPUFREQ_GOV_LIMITS:
+ return sugov_limits(policy);
+ }
+ }
+ return -EINVAL;
+}
+
+static struct cpufreq_governor schedutil_gov = {
+ .name = "schedutil",
+ .governor = sugov_governor,
+ .owner = THIS_MODULE,
+};
+
+static int __init sugov_module_init(void)
+{
+ return cpufreq_register_governor(&schedutil_gov);
+}
+
+static void __exit sugov_module_exit(void)
+{
+ cpufreq_unregister_governor(&schedutil_gov);
+}
+
+MODULE_AUTHOR("Rafael J. Wysocki <rafael.j.wysocki@intel.com>");
+MODULE_DESCRIPTION("Utilization-based CPU frequency selection");
+MODULE_LICENSE("GPL");
+
+#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL
+struct cpufreq_governor *cpufreq_default_governor(void)
+{
+ return &schedutil_gov;
+}
+
+fs_initcall(sugov_module_init);
+#else
+module_init(sugov_module_init);
+#endif
+module_exit(sugov_module_exit);
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 981fcd7dc394..11e9705bf937 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -103,11 +103,11 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
if (skip)
continue;
- if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids)
+ if (cpumask_any_and(tsk_cpus_allowed(p), vec->mask) >= nr_cpu_ids)
continue;
if (lowest_mask) {
- cpumask_and(lowest_mask, &p->cpus_allowed, vec->mask);
+ cpumask_and(lowest_mask, tsk_cpus_allowed(p), vec->mask);
/*
* We have to ensure that we have at least one bit
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index affd97ec9f65..fcb7f0217ff4 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -134,7 +134,7 @@ static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct task_struct *p = dl_task_of(dl_se);
- if (p->nr_cpus_allowed > 1)
+ if (tsk_nr_cpus_allowed(p) > 1)
dl_rq->dl_nr_migratory++;
update_dl_migration(dl_rq);
@@ -144,7 +144,7 @@ static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct task_struct *p = dl_task_of(dl_se);
- if (p->nr_cpus_allowed > 1)
+ if (tsk_nr_cpus_allowed(p) > 1)
dl_rq->dl_nr_migratory--;
update_dl_migration(dl_rq);
@@ -591,10 +591,10 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
struct sched_dl_entity,
dl_timer);
struct task_struct *p = dl_task_of(dl_se);
- unsigned long flags;
+ struct rq_flags rf;
struct rq *rq;
- rq = task_rq_lock(p, &flags);
+ rq = task_rq_lock(p, &rf);
/*
* The task might have changed its scheduling policy to something
@@ -670,14 +670,14 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
* Nothing relies on rq->lock after this, so its safe to drop
* rq->lock.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, rf.cookie);
push_dl_task(rq);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, rf.cookie);
}
#endif
unlock:
- task_rq_unlock(rq, p, &flags);
+ task_rq_unlock(rq, p, &rf);
/*
* This can free the task_struct, including this hrtimer, do not touch
@@ -717,10 +717,6 @@ static void update_curr_dl(struct rq *rq)
if (!dl_task(curr) || !on_dl_rq(dl_se))
return;
- /* Kick cpufreq (see the comment in linux/cpufreq.h). */
- if (cpu_of(rq) == smp_processor_id())
- cpufreq_trigger_update(rq_clock(rq));
-
/*
* Consumed budget is computed considering the time as
* observed by schedulable tasks (excluding time spent
@@ -736,6 +732,10 @@ static void update_curr_dl(struct rq *rq)
return;
}
+ /* kick cpufreq (see the comment in linux/cpufreq.h). */
+ if (cpu_of(rq) == smp_processor_id())
+ cpufreq_trigger_update(rq_clock(rq));
+
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
@@ -966,7 +966,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
enqueue_dl_entity(&p->dl, pi_se, flags);
- if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
+ if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1)
enqueue_pushable_dl_task(rq, p);
}
@@ -1040,9 +1040,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags)
* try to make it stay here, it might be important.
*/
if (unlikely(dl_task(curr)) &&
- (curr->nr_cpus_allowed < 2 ||
+ (tsk_nr_cpus_allowed(curr) < 2 ||
!dl_entity_preempt(&p->dl, &curr->dl)) &&
- (p->nr_cpus_allowed > 1)) {
+ (tsk_nr_cpus_allowed(p) > 1)) {
int target = find_later_rq(p);
if (target != -1 &&
@@ -1063,7 +1063,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
* Current can't be migrated, useless to reschedule,
* let's hope p can move out.
*/
- if (rq->curr->nr_cpus_allowed == 1 ||
+ if (tsk_nr_cpus_allowed(rq->curr) == 1 ||
cpudl_find(&rq->rd->cpudl, rq->curr, NULL) == -1)
return;
@@ -1071,7 +1071,7 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
* p is migratable, so let's not schedule it and
* see if it is pushed or pulled somewhere else.
*/
- if (p->nr_cpus_allowed != 1 &&
+ if (tsk_nr_cpus_allowed(p) != 1 &&
cpudl_find(&rq->rd->cpudl, p, NULL) != -1)
return;
@@ -1125,7 +1125,8 @@ static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq,
return rb_entry(left, struct sched_dl_entity, rb_node);
}
-struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev)
+struct task_struct *
+pick_next_task_dl(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie)
{
struct sched_dl_entity *dl_se;
struct task_struct *p;
@@ -1140,9 +1141,9 @@ struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev)
* disabled avoiding further scheduler activity on it and we're
* being very careful to re-start the picking loop.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
pull_dl_task(rq);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, cookie);
/*
* pull_rt_task() can drop (and re-acquire) rq->lock; this
* means a stop task can slip in, in which case we need to
@@ -1185,7 +1186,7 @@ static void put_prev_task_dl(struct rq *rq, struct task_struct *p)
{
update_curr_dl(rq);
- if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1)
+ if (on_dl_rq(&p->dl) && tsk_nr_cpus_allowed(p) > 1)
enqueue_pushable_dl_task(rq, p);
}
@@ -1286,7 +1287,7 @@ static int find_later_rq(struct task_struct *task)
if (unlikely(!later_mask))
return -1;
- if (task->nr_cpus_allowed == 1)
+ if (tsk_nr_cpus_allowed(task) == 1)
return -1;
/*
@@ -1392,8 +1393,9 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq)
if (double_lock_balance(rq, later_rq)) {
if (unlikely(task_rq(task) != rq ||
!cpumask_test_cpu(later_rq->cpu,
- &task->cpus_allowed) ||
+ tsk_cpus_allowed(task)) ||
task_running(rq, task) ||
+ !dl_task(task) ||
!task_on_rq_queued(task))) {
double_unlock_balance(rq, later_rq);
later_rq = NULL;
@@ -1431,7 +1433,7 @@ static struct task_struct *pick_next_pushable_dl_task(struct rq *rq)
BUG_ON(rq->cpu != task_cpu(p));
BUG_ON(task_current(rq, p));
- BUG_ON(p->nr_cpus_allowed <= 1);
+ BUG_ON(tsk_nr_cpus_allowed(p) <= 1);
BUG_ON(!task_on_rq_queued(p));
BUG_ON(!dl_task(p));
@@ -1470,7 +1472,7 @@ retry:
*/
if (dl_task(rq->curr) &&
dl_time_before(next_task->dl.deadline, rq->curr->dl.deadline) &&
- rq->curr->nr_cpus_allowed > 1) {
+ tsk_nr_cpus_allowed(rq->curr) > 1) {
resched_curr(rq);
return 0;
}
@@ -1617,9 +1619,9 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
{
if (!task_running(rq, p) &&
!test_tsk_need_resched(rq->curr) &&
- p->nr_cpus_allowed > 1 &&
+ tsk_nr_cpus_allowed(p) > 1 &&
dl_task(rq->curr) &&
- (rq->curr->nr_cpus_allowed < 2 ||
+ (tsk_nr_cpus_allowed(rq->curr) < 2 ||
!dl_entity_preempt(&p->dl, &rq->curr->dl))) {
push_dl_tasks(rq);
}
@@ -1723,7 +1725,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
- if (p->nr_cpus_allowed > 1 && rq->dl.overloaded)
+ if (tsk_nr_cpus_allowed(p) > 1 && rq->dl.overloaded)
queue_push_tasks(rq);
#else
if (dl_task(rq->curr))
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 4fbc3bd5ff60..cf905f655ba1 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -626,15 +626,16 @@ do { \
#undef P
#undef PN
-#ifdef CONFIG_SCHEDSTATS
-#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
-#define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n);
-
#ifdef CONFIG_SMP
+#define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n);
P64(avg_idle);
P64(max_idle_balance_cost);
+#undef P64
#endif
+#ifdef CONFIG_SCHEDSTATS
+#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
+
if (schedstat_enabled()) {
P(yld_count);
P(sched_count);
@@ -644,7 +645,6 @@ do { \
}
#undef P
-#undef P64
#endif
spin_lock_irqsave(&sched_debug_lock, flags);
print_cfs_stats(m, cpu);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 0fe30e66aff1..218f8e83db73 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -204,7 +204,7 @@ static void __update_inv_weight(struct load_weight *lw)
* OR
* (delta_exec * (weight * lw->inv_weight)) >> WMULT_SHIFT
*
- * Either weight := NICE_0_LOAD and lw \e prio_to_wmult[], in which case
+ * Either weight := NICE_0_LOAD and lw \e sched_prio_to_wmult[], in which case
* we're guaranteed shift stays positive because inv_weight is guaranteed to
* fit 32 bits, and NICE_0_LOAD gives another 10 bits; therefore shift >= 22.
*
@@ -682,17 +682,68 @@ void init_entity_runnable_average(struct sched_entity *se)
sa->period_contrib = 1023;
sa->load_avg = scale_load_down(se->load.weight);
sa->load_sum = sa->load_avg * LOAD_AVG_MAX;
- sa->util_avg = scale_load_down(SCHED_LOAD_SCALE);
- sa->util_sum = sa->util_avg * LOAD_AVG_MAX;
+ /*
+ * At this point, util_avg won't be used in select_task_rq_fair anyway
+ */
+ sa->util_avg = 0;
+ sa->util_sum = 0;
/* when this task enqueue'ed, it will contribute to its cfs_rq's load_avg */
}
+/*
+ * With new tasks being created, their initial util_avgs are extrapolated
+ * based on the cfs_rq's current util_avg:
+ *
+ * util_avg = cfs_rq->util_avg / (cfs_rq->load_avg + 1) * se.load.weight
+ *
+ * However, in many cases, the above util_avg does not give a desired
+ * value. Moreover, the sum of the util_avgs may be divergent, such
+ * as when the series is a harmonic series.
+ *
+ * To solve this problem, we also cap the util_avg of successive tasks to
+ * only 1/2 of the left utilization budget:
+ *
+ * util_avg_cap = (1024 - cfs_rq->avg.util_avg) / 2^n
+ *
+ * where n denotes the nth task.
+ *
+ * For example, a simplest series from the beginning would be like:
+ *
+ * task util_avg: 512, 256, 128, 64, 32, 16, 8, ...
+ * cfs_rq util_avg: 512, 768, 896, 960, 992, 1008, 1016, ...
+ *
+ * Finally, that extrapolated util_avg is clamped to the cap (util_avg_cap)
+ * if util_avg > util_avg_cap.
+ */
+void post_init_entity_util_avg(struct sched_entity *se)
+{
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ struct sched_avg *sa = &se->avg;
+ long cap = (long)(SCHED_CAPACITY_SCALE - cfs_rq->avg.util_avg) / 2;
+
+ if (cap > 0) {
+ if (cfs_rq->avg.util_avg != 0) {
+ sa->util_avg = cfs_rq->avg.util_avg * se->load.weight;
+ sa->util_avg /= (cfs_rq->avg.load_avg + 1);
+
+ if (sa->util_avg > cap)
+ sa->util_avg = cap;
+ } else {
+ sa->util_avg = cap;
+ }
+ sa->util_sum = sa->util_avg * LOAD_AVG_MAX;
+ }
+}
+
static inline unsigned long cfs_rq_runnable_load_avg(struct cfs_rq *cfs_rq);
static inline unsigned long cfs_rq_load_avg(struct cfs_rq *cfs_rq);
#else
void init_entity_runnable_average(struct sched_entity *se)
{
}
+void post_init_entity_util_avg(struct sched_entity *se)
+{
+}
#endif
/*
@@ -2437,10 +2488,12 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
update_load_sub(&cfs_rq->load, se->load.weight);
if (!parent_entity(se))
update_load_sub(&rq_of(cfs_rq)->load, se->load.weight);
+#ifdef CONFIG_SMP
if (entity_is_task(se)) {
account_numa_dequeue(rq_of(cfs_rq), task_of(se));
list_del_init(&se->group_node);
}
+#endif
cfs_rq->nr_running--;
}
@@ -2550,6 +2603,16 @@ static const u32 runnable_avg_yN_sum[] = {
};
/*
+ * Precomputed \Sum y^k { 1<=k<=n, where n%32=0). Values are rolled down to
+ * lower integers. See Documentation/scheduler/sched-avg.txt how these
+ * were generated:
+ */
+static const u32 __accumulated_sum_N32[] = {
+ 0, 23371, 35056, 40899, 43820, 45281,
+ 46011, 46376, 46559, 46650, 46696, 46719,
+};
+
+/*
* Approximate:
* val * y^n, where y^32 ~= 0.5 (~1 scheduling period)
*/
@@ -2597,22 +2660,13 @@ static u32 __compute_runnable_contrib(u64 n)
else if (unlikely(n >= LOAD_AVG_MAX_N))
return LOAD_AVG_MAX;
- /* Compute \Sum k^n combining precomputed values for k^i, \Sum k^j */
- do {
- contrib /= 2; /* y^LOAD_AVG_PERIOD = 1/2 */
- contrib += runnable_avg_yN_sum[LOAD_AVG_PERIOD];
-
- n -= LOAD_AVG_PERIOD;
- } while (n > LOAD_AVG_PERIOD);
-
+ /* Since n < LOAD_AVG_MAX_N, n/LOAD_AVG_PERIOD < 11 */
+ contrib = __accumulated_sum_N32[n/LOAD_AVG_PERIOD];
+ n %= LOAD_AVG_PERIOD;
contrib = decay_load(contrib, n);
return contrib + runnable_avg_yN_sum[n];
}
-#if (SCHED_LOAD_SHIFT - SCHED_LOAD_RESOLUTION) != 10 || SCHED_CAPACITY_SHIFT != 10
-#error "load tracking assumes 2^10 as unit"
-#endif
-
#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
/*
@@ -2821,23 +2875,54 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force) {}
static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq);
+static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq)
+{
+ struct rq *rq = rq_of(cfs_rq);
+ int cpu = cpu_of(rq);
+
+ if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) {
+ unsigned long max = rq->cpu_capacity_orig;
+
+ /*
+ * There are a few boundary cases this might miss but it should
+ * get called often enough that that should (hopefully) not be
+ * a real problem -- added to that it only calls on the local
+ * CPU, so if we enqueue remotely we'll miss an update, but
+ * the next tick/schedule should update.
+ *
+ * It will not get called when we go idle, because the idle
+ * thread is a different class (!fair), nor will the utilization
+ * number include things like RT tasks.
+ *
+ * As is, the util number is not freq-invariant (we'd have to
+ * implement arch_scale_freq_capacity() for that).
+ *
+ * See cpu_util().
+ */
+ cpufreq_update_util(rq_clock(rq),
+ min(cfs_rq->avg.util_avg, max), max);
+ }
+}
+
/* Group cfs_rq's load_avg is used for task_h_load and update_cfs_share */
-static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
+static inline int
+update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq, bool update_freq)
{
struct sched_avg *sa = &cfs_rq->avg;
- int decayed, removed = 0;
+ int decayed, removed_load = 0, removed_util = 0;
if (atomic_long_read(&cfs_rq->removed_load_avg)) {
s64 r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0);
sa->load_avg = max_t(long, sa->load_avg - r, 0);
sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0);
- removed = 1;
+ removed_load = 1;
}
if (atomic_long_read(&cfs_rq->removed_util_avg)) {
long r = atomic_long_xchg(&cfs_rq->removed_util_avg, 0);
sa->util_avg = max_t(long, sa->util_avg - r, 0);
sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0);
+ removed_util = 1;
}
decayed = __update_load_avg(now, cpu_of(rq_of(cfs_rq)), sa,
@@ -2848,7 +2933,10 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
cfs_rq->load_last_update_time_copy = sa->last_update_time;
#endif
- return decayed || removed;
+ if (update_freq && (decayed || removed_util))
+ cfs_rq_util_change(cfs_rq);
+
+ return decayed || removed_load;
}
/* Update task and its cfs_rq load average */
@@ -2867,31 +2955,8 @@ static inline void update_load_avg(struct sched_entity *se, int update_tg)
se->on_rq * scale_load_down(se->load.weight),
cfs_rq->curr == se, NULL);
- if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg)
+ if (update_cfs_rq_load_avg(now, cfs_rq, true) && update_tg)
update_tg_load_avg(cfs_rq, 0);
-
- if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) {
- unsigned long max = rq->cpu_capacity_orig;
-
- /*
- * There are a few boundary cases this might miss but it should
- * get called often enough that that should (hopefully) not be
- * a real problem -- added to that it only calls on the local
- * CPU, so if we enqueue remotely we'll miss an update, but
- * the next tick/schedule should update.
- *
- * It will not get called when we go idle, because the idle
- * thread is a different class (!fair), nor will the utilization
- * number include things like RT tasks.
- *
- * As is, the util number is not freq-invariant (we'd have to
- * implement arch_scale_freq_capacity() for that).
- *
- * See cpu_util().
- */
- cpufreq_update_util(rq_clock(rq),
- min(cfs_rq->avg.util_avg, max), max);
- }
}
static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
@@ -2919,6 +2984,8 @@ skip_aging:
cfs_rq->avg.load_sum += se->avg.load_sum;
cfs_rq->avg.util_avg += se->avg.util_avg;
cfs_rq->avg.util_sum += se->avg.util_sum;
+
+ cfs_rq_util_change(cfs_rq);
}
static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
@@ -2931,6 +2998,8 @@ static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *s
cfs_rq->avg.load_sum = max_t(s64, cfs_rq->avg.load_sum - se->avg.load_sum, 0);
cfs_rq->avg.util_avg = max_t(long, cfs_rq->avg.util_avg - se->avg.util_avg, 0);
cfs_rq->avg.util_sum = max_t(s32, cfs_rq->avg.util_sum - se->avg.util_sum, 0);
+
+ cfs_rq_util_change(cfs_rq);
}
/* Add the load generated by se into cfs_rq's load average */
@@ -2948,7 +3017,7 @@ enqueue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
cfs_rq->curr == se, NULL);
}
- decayed = update_cfs_rq_load_avg(now, cfs_rq);
+ decayed = update_cfs_rq_load_avg(now, cfs_rq, !migrated);
cfs_rq->runnable_load_avg += sa->load_avg;
cfs_rq->runnable_load_sum += sa->load_sum;
@@ -3030,7 +3099,14 @@ static int idle_balance(struct rq *this_rq);
#else /* CONFIG_SMP */
-static inline void update_load_avg(struct sched_entity *se, int update_tg) {}
+static inline void update_load_avg(struct sched_entity *se, int not_used)
+{
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ struct rq *rq = rq_of(cfs_rq);
+
+ cpufreq_trigger_update(rq_clock(rq));
+}
+
static inline void
enqueue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {}
static inline void
@@ -3178,10 +3254,41 @@ static inline void check_schedstat_required(void)
#endif
}
+
+/*
+ * MIGRATION
+ *
+ * dequeue
+ * update_curr()
+ * update_min_vruntime()
+ * vruntime -= min_vruntime
+ *
+ * enqueue
+ * update_curr()
+ * update_min_vruntime()
+ * vruntime += min_vruntime
+ *
+ * this way the vruntime transition between RQs is done when both
+ * min_vruntime are up-to-date.
+ *
+ * WAKEUP (remote)
+ *
+ * ->migrate_task_rq_fair() (p->state == TASK_WAKING)
+ * vruntime -= min_vruntime
+ *
+ * enqueue
+ * update_curr()
+ * update_min_vruntime()
+ * vruntime += min_vruntime
+ *
+ * this way we don't have the most up-to-date min_vruntime on the originating
+ * CPU and an up-to-date min_vruntime on the destination CPU.
+ */
+
static void
enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
{
- bool renorm = !(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_WAKING);
+ bool renorm = !(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_MIGRATED);
bool curr = cfs_rq->curr == se;
/*
@@ -3195,7 +3302,9 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
/*
* Otherwise, renormalise after, such that we're placed at the current
- * moment in time, instead of some random moment in the past.
+ * moment in time, instead of some random moment in the past. Being
+ * placed in the past could significantly boost this task to the
+ * fairness detriment of existing tasks.
*/
if (renorm && !curr)
se->vruntime += cfs_rq->min_vruntime;
@@ -4423,7 +4532,7 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
}
#ifdef CONFIG_SMP
-
+#ifdef CONFIG_NO_HZ_COMMON
/*
* per rq 'load' arrray crap; XXX kill this.
*/
@@ -4489,13 +4598,13 @@ decay_load_missed(unsigned long load, unsigned long missed_updates, int idx)
}
return load;
}
+#endif /* CONFIG_NO_HZ_COMMON */
/**
- * __update_cpu_load - update the rq->cpu_load[] statistics
+ * __cpu_load_update - update the rq->cpu_load[] statistics
* @this_rq: The rq to update statistics for
* @this_load: The current load
* @pending_updates: The number of missed updates
- * @active: !0 for NOHZ_FULL
*
* Update rq->cpu_load[] statistics. This function is usually called every
* scheduler tick (TICK_NSEC).
@@ -4524,12 +4633,12 @@ decay_load_missed(unsigned long load, unsigned long missed_updates, int idx)
* load[i]_n = (1 - 1/2^i)^n * load[i]_0
*
* see decay_load_misses(). For NOHZ_FULL we get to subtract and add the extra
- * term. See the @active paramter.
+ * term.
*/
-static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
- unsigned long pending_updates, int active)
+static void cpu_load_update(struct rq *this_rq, unsigned long this_load,
+ unsigned long pending_updates)
{
- unsigned long tickless_load = active ? this_rq->cpu_load[0] : 0;
+ unsigned long __maybe_unused tickless_load = this_rq->cpu_load[0];
int i, scale;
this_rq->nr_load_updates++;
@@ -4542,6 +4651,7 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
/* scale is effectively 1 << i now, and >> i divides by scale */
old_load = this_rq->cpu_load[i];
+#ifdef CONFIG_NO_HZ_COMMON
old_load = decay_load_missed(old_load, pending_updates - 1, i);
if (tickless_load) {
old_load -= decay_load_missed(tickless_load, pending_updates - 1, i);
@@ -4552,6 +4662,7 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
*/
old_load += tickless_load;
}
+#endif
new_load = this_load;
/*
* Round up the averaging division if load is increasing. This
@@ -4574,10 +4685,23 @@ static unsigned long weighted_cpuload(const int cpu)
}
#ifdef CONFIG_NO_HZ_COMMON
-static void __update_cpu_load_nohz(struct rq *this_rq,
- unsigned long curr_jiffies,
- unsigned long load,
- int active)
+/*
+ * There is no sane way to deal with nohz on smp when using jiffies because the
+ * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
+ * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}.
+ *
+ * Therefore we need to avoid the delta approach from the regular tick when
+ * possible since that would seriously skew the load calculation. This is why we
+ * use cpu_load_update_periodic() for CPUs out of nohz. However we'll rely on
+ * jiffies deltas for updates happening while in nohz mode (idle ticks, idle
+ * loop exit, nohz_idle_balance, nohz full exit...)
+ *
+ * This means we might still be one tick off for nohz periods.
+ */
+
+static void cpu_load_update_nohz(struct rq *this_rq,
+ unsigned long curr_jiffies,
+ unsigned long load)
{
unsigned long pending_updates;
@@ -4589,28 +4713,15 @@ static void __update_cpu_load_nohz(struct rq *this_rq,
* In the NOHZ_FULL case, we were non-idle, we should consider
* its weighted load.
*/
- __update_cpu_load(this_rq, load, pending_updates, active);
+ cpu_load_update(this_rq, load, pending_updates);
}
}
/*
- * There is no sane way to deal with nohz on smp when using jiffies because the
- * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
- * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}.
- *
- * Therefore we cannot use the delta approach from the regular tick since that
- * would seriously skew the load calculation. However we'll make do for those
- * updates happening while idle (nohz_idle_balance) or coming out of idle
- * (tick_nohz_idle_exit).
- *
- * This means we might still be one tick off for nohz periods.
- */
-
-/*
* Called from nohz_idle_balance() to update the load ratings before doing the
* idle balance.
*/
-static void update_cpu_load_idle(struct rq *this_rq)
+static void cpu_load_update_idle(struct rq *this_rq)
{
/*
* bail if there's load or we're actually up-to-date.
@@ -4618,38 +4729,71 @@ static void update_cpu_load_idle(struct rq *this_rq)
if (weighted_cpuload(cpu_of(this_rq)))
return;
- __update_cpu_load_nohz(this_rq, READ_ONCE(jiffies), 0, 0);
+ cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), 0);
}
/*
- * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed.
+ * Record CPU load on nohz entry so we know the tickless load to account
+ * on nohz exit. cpu_load[0] happens then to be updated more frequently
+ * than other cpu_load[idx] but it should be fine as cpu_load readers
+ * shouldn't rely into synchronized cpu_load[*] updates.
*/
-void update_cpu_load_nohz(int active)
+void cpu_load_update_nohz_start(void)
{
struct rq *this_rq = this_rq();
+
+ /*
+ * This is all lockless but should be fine. If weighted_cpuload changes
+ * concurrently we'll exit nohz. And cpu_load write can race with
+ * cpu_load_update_idle() but both updater would be writing the same.
+ */
+ this_rq->cpu_load[0] = weighted_cpuload(cpu_of(this_rq));
+}
+
+/*
+ * Account the tickless load in the end of a nohz frame.
+ */
+void cpu_load_update_nohz_stop(void)
+{
unsigned long curr_jiffies = READ_ONCE(jiffies);
- unsigned long load = active ? weighted_cpuload(cpu_of(this_rq)) : 0;
+ struct rq *this_rq = this_rq();
+ unsigned long load;
if (curr_jiffies == this_rq->last_load_update_tick)
return;
+ load = weighted_cpuload(cpu_of(this_rq));
raw_spin_lock(&this_rq->lock);
- __update_cpu_load_nohz(this_rq, curr_jiffies, load, active);
+ update_rq_clock(this_rq);
+ cpu_load_update_nohz(this_rq, curr_jiffies, load);
raw_spin_unlock(&this_rq->lock);
}
-#endif /* CONFIG_NO_HZ */
+#else /* !CONFIG_NO_HZ_COMMON */
+static inline void cpu_load_update_nohz(struct rq *this_rq,
+ unsigned long curr_jiffies,
+ unsigned long load) { }
+#endif /* CONFIG_NO_HZ_COMMON */
+
+static void cpu_load_update_periodic(struct rq *this_rq, unsigned long load)
+{
+#ifdef CONFIG_NO_HZ_COMMON
+ /* See the mess around cpu_load_update_nohz(). */
+ this_rq->last_load_update_tick = READ_ONCE(jiffies);
+#endif
+ cpu_load_update(this_rq, load, 1);
+}
/*
* Called from scheduler_tick()
*/
-void update_cpu_load_active(struct rq *this_rq)
+void cpu_load_update_active(struct rq *this_rq)
{
unsigned long load = weighted_cpuload(cpu_of(this_rq));
- /*
- * See the mess around update_cpu_load_idle() / update_cpu_load_nohz().
- */
- this_rq->last_load_update_tick = jiffies;
- __update_cpu_load(this_rq, load, 1, 1);
+
+ if (tick_nohz_tick_stopped())
+ cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), load);
+ else
+ cpu_load_update_periodic(this_rq, load);
}
/*
@@ -4707,46 +4851,6 @@ static unsigned long cpu_avg_load_per_task(int cpu)
return 0;
}
-static void record_wakee(struct task_struct *p)
-{
- /*
- * Rough decay (wiping) for cost saving, don't worry
- * about the boundary, really active task won't care
- * about the loss.
- */
- if (time_after(jiffies, current->wakee_flip_decay_ts + HZ)) {
- current->wakee_flips >>= 1;
- current->wakee_flip_decay_ts = jiffies;
- }
-
- if (current->last_wakee != p) {
- current->last_wakee = p;
- current->wakee_flips++;
- }
-}
-
-static void task_waking_fair(struct task_struct *p)
-{
- struct sched_entity *se = &p->se;
- struct cfs_rq *cfs_rq = cfs_rq_of(se);
- u64 min_vruntime;
-
-#ifndef CONFIG_64BIT
- u64 min_vruntime_copy;
-
- do {
- min_vruntime_copy = cfs_rq->min_vruntime_copy;
- smp_rmb();
- min_vruntime = cfs_rq->min_vruntime;
- } while (min_vruntime != min_vruntime_copy);
-#else
- min_vruntime = cfs_rq->min_vruntime;
-#endif
-
- se->vruntime -= min_vruntime;
- record_wakee(p);
-}
-
#ifdef CONFIG_FAIR_GROUP_SCHED
/*
* effective_load() calculates the load change as seen from the root_task_group
@@ -4862,17 +4966,39 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
#endif
+static void record_wakee(struct task_struct *p)
+{
+ /*
+ * Only decay a single time; tasks that have less then 1 wakeup per
+ * jiffy will not have built up many flips.
+ */
+ if (time_after(jiffies, current->wakee_flip_decay_ts + HZ)) {
+ current->wakee_flips >>= 1;
+ current->wakee_flip_decay_ts = jiffies;
+ }
+
+ if (current->last_wakee != p) {
+ current->last_wakee = p;
+ current->wakee_flips++;
+ }
+}
+
/*
* Detect M:N waker/wakee relationships via a switching-frequency heuristic.
+ *
* A waker of many should wake a different task than the one last awakened
- * at a frequency roughly N times higher than one of its wakees. In order
- * to determine whether we should let the load spread vs consolodating to
- * shared cache, we look for a minimum 'flip' frequency of llc_size in one
- * partner, and a factor of lls_size higher frequency in the other. With
- * both conditions met, we can be relatively sure that the relationship is
- * non-monogamous, with partner count exceeding socket size. Waker/wakee
- * being client/server, worker/dispatcher, interrupt source or whatever is
- * irrelevant, spread criteria is apparent partner count exceeds socket size.
+ * at a frequency roughly N times higher than one of its wakees.
+ *
+ * In order to determine whether we should let the load spread vs consolidating
+ * to shared cache, we look for a minimum 'flip' frequency of llc_size in one
+ * partner, and a factor of lls_size higher frequency in the other.
+ *
+ * With both conditions met, we can be relatively sure that the relationship is
+ * non-monogamous, with partner count exceeding socket size.
+ *
+ * Waker/wakee being client/server, worker/dispatcher, interrupt source or
+ * whatever is irrelevant, spread criteria is apparent partner count exceeds
+ * socket size.
*/
static int wake_wide(struct task_struct *p)
{
@@ -5177,8 +5303,10 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f
int want_affine = 0;
int sync = wake_flags & WF_SYNC;
- if (sd_flag & SD_BALANCE_WAKE)
+ if (sd_flag & SD_BALANCE_WAKE) {
+ record_wakee(p);
want_affine = !wake_wide(p) && cpumask_test_cpu(cpu, tsk_cpus_allowed(p));
+ }
rcu_read_lock();
for_each_domain(cpu, tmp) {
@@ -5258,6 +5386,32 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f
static void migrate_task_rq_fair(struct task_struct *p)
{
/*
+ * As blocked tasks retain absolute vruntime the migration needs to
+ * deal with this by subtracting the old and adding the new
+ * min_vruntime -- the latter is done by enqueue_entity() when placing
+ * the task on the new runqueue.
+ */
+ if (p->state == TASK_WAKING) {
+ struct sched_entity *se = &p->se;
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ u64 min_vruntime;
+
+#ifndef CONFIG_64BIT
+ u64 min_vruntime_copy;
+
+ do {
+ min_vruntime_copy = cfs_rq->min_vruntime_copy;
+ smp_rmb();
+ min_vruntime = cfs_rq->min_vruntime;
+ } while (min_vruntime != min_vruntime_copy);
+#else
+ min_vruntime = cfs_rq->min_vruntime;
+#endif
+
+ se->vruntime -= min_vruntime;
+ }
+
+ /*
* We are supposed to update the task to "current" time, then its up to date
* and ready to go to new CPU/cfs_rq. But we have difficulty in getting
* what current time is, so simply throw away the out-of-date time. This
@@ -5440,7 +5594,7 @@ preempt:
}
static struct task_struct *
-pick_next_task_fair(struct rq *rq, struct task_struct *prev)
+pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie)
{
struct cfs_rq *cfs_rq = &rq->cfs;
struct sched_entity *se;
@@ -5553,9 +5707,9 @@ idle:
* further scheduler activity on it and we're being very careful to
* re-start the picking loop.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
new_tasks = idle_balance(rq);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, cookie);
/*
* Because idle_balance() releases (and re-acquires) rq->lock, it is
* possible for any higher priority task to appear. In that case we
@@ -5654,7 +5808,7 @@ static bool yield_to_task_fair(struct rq *rq, struct task_struct *p, bool preemp
* W_i,0 = \Sum_j w_i,j (2)
*
* Where w_i,j is the weight of the j-th runnable task on cpu i. This weight
- * is derived from the nice value as per prio_to_weight[].
+ * is derived from the nice value as per sched_prio_to_weight[].
*
* The weight average is an exponential decay average of the instantaneous
* weight:
@@ -6156,7 +6310,7 @@ static void update_blocked_averages(int cpu)
if (throttled_hierarchy(cfs_rq))
continue;
- if (update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq))
+ if (update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true))
update_tg_load_avg(cfs_rq, 0);
}
raw_spin_unlock_irqrestore(&rq->lock, flags);
@@ -6217,7 +6371,7 @@ static inline void update_blocked_averages(int cpu)
raw_spin_lock_irqsave(&rq->lock, flags);
update_rq_clock(rq);
- update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq);
+ update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true);
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
@@ -6626,6 +6780,9 @@ static bool update_sd_pick_busiest(struct lb_env *env,
if (!(env->sd->flags & SD_ASYM_PACKING))
return true;
+ /* No ASYM_PACKING if target cpu is already busy */
+ if (env->idle == CPU_NOT_IDLE)
+ return true;
/*
* ASYM_PACKING needs to move all the work to the lowest
* numbered CPUs in the group, therefore mark all groups
@@ -6635,7 +6792,8 @@ static bool update_sd_pick_busiest(struct lb_env *env,
if (!sds->busiest)
return true;
- if (group_first_cpu(sds->busiest) > group_first_cpu(sg))
+ /* Prefer to move from highest possible cpu's work */
+ if (group_first_cpu(sds->busiest) < group_first_cpu(sg))
return true;
}
@@ -6781,6 +6939,9 @@ static int check_asym_packing(struct lb_env *env, struct sd_lb_stats *sds)
if (!(env->sd->flags & SD_ASYM_PACKING))
return 0;
+ if (env->idle == CPU_NOT_IDLE)
+ return 0;
+
if (!sds->busiest)
return 0;
@@ -6889,9 +7050,10 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
}
/*
- * In the presence of smp nice balancing, certain scenarios can have
- * max load less than avg load(as we skip the groups at or below
- * its cpu_capacity, while calculating max_load..)
+ * Avg load of busiest sg can be less and avg load of local sg can
+ * be greater than avg load across all sgs of sd because avg load
+ * factors in sg capacity and sgs with smaller group_type are
+ * skipped when updating the busiest sg:
*/
if (busiest->avg_load <= sds->avg_load ||
local->avg_load >= sds->avg_load) {
@@ -6904,11 +7066,12 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
*/
if (busiest->group_type == group_overloaded &&
local->group_type == group_overloaded) {
- load_above_capacity = busiest->sum_nr_running *
- SCHED_LOAD_SCALE;
- if (load_above_capacity > busiest->group_capacity)
+ load_above_capacity = busiest->sum_nr_running * SCHED_CAPACITY_SCALE;
+ if (load_above_capacity > busiest->group_capacity) {
load_above_capacity -= busiest->group_capacity;
- else
+ load_above_capacity *= NICE_0_LOAD;
+ load_above_capacity /= busiest->group_capacity;
+ } else
load_above_capacity = ~0UL;
}
@@ -6916,9 +7079,8 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
* We're trying to get all the cpus to the average_load, so we don't
* want to push ourselves above the average load, nor do we wish to
* reduce the max loaded cpu below the average load. At the same time,
- * we also don't want to reduce the group load below the group capacity
- * (so that we can implement power-savings policies etc). Thus we look
- * for the minimum possible imbalance.
+ * we also don't want to reduce the group load below the group
+ * capacity. Thus we look for the minimum possible imbalance.
*/
max_pull = min(busiest->avg_load - sds->avg_load, load_above_capacity);
@@ -6942,10 +7104,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
/**
* find_busiest_group - Returns the busiest group within the sched_domain
- * if there is an imbalance. If there isn't an imbalance, and
- * the user has opted for power-savings, it returns a group whose
- * CPUs can be put to idle by rebalancing those tasks elsewhere, if
- * such a group exists.
+ * if there is an imbalance.
*
* Also calculates the amount of weighted load which should be moved
* to restore balance.
@@ -6953,9 +7112,6 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
* @env: The load balancing environment.
*
* Return: - The busiest group if imbalance exists.
- * - If no imbalance and user has opted for power-savings balance,
- * return the least loaded group whose CPUs can be
- * put to idle by rebalancing its tasks onto our group.
*/
static struct sched_group *find_busiest_group(struct lb_env *env)
{
@@ -6973,8 +7129,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
busiest = &sds.busiest_stat;
/* ASYM feature bypasses nice load balance check */
- if ((env->idle == CPU_IDLE || env->idle == CPU_NEWLY_IDLE) &&
- check_asym_packing(env, &sds))
+ if (check_asym_packing(env, &sds))
return sds.busiest;
/* There is no busy sibling group to pull tasks from */
@@ -7399,10 +7554,7 @@ more_balance:
&busiest->active_balance_work);
}
- /*
- * We've kicked active balancing, reset the failure
- * counter.
- */
+ /* We've kicked active balancing, force task migration. */
sd->nr_balance_failed = sd->cache_nice_tries+1;
}
} else
@@ -7637,10 +7789,13 @@ static int active_load_balance_cpu_stop(void *data)
schedstat_inc(sd, alb_count);
p = detach_one_task(&env);
- if (p)
+ if (p) {
schedstat_inc(sd, alb_pushed);
- else
+ /* Active balancing done, reset the failure counter. */
+ sd->nr_balance_failed = 0;
+ } else {
schedstat_inc(sd, alb_failed);
+ }
}
rcu_read_unlock();
out_unlock:
@@ -7711,7 +7866,7 @@ static void nohz_balancer_kick(void)
return;
}
-static inline void nohz_balance_exit_idle(int cpu)
+void nohz_balance_exit_idle(unsigned int cpu)
{
if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
/*
@@ -7784,18 +7939,6 @@ void nohz_balance_enter_idle(int cpu)
atomic_inc(&nohz.nr_cpus);
set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
}
-
-static int sched_ilb_notifier(struct notifier_block *nfb,
- unsigned long action, void *hcpu)
-{
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_DYING:
- nohz_balance_exit_idle(smp_processor_id());
- return NOTIFY_OK;
- default:
- return NOTIFY_DONE;
- }
-}
#endif
static DEFINE_SPINLOCK(balancing);
@@ -7957,7 +8100,7 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle)
if (time_after_eq(jiffies, rq->next_balance)) {
raw_spin_lock_irq(&rq->lock);
update_rq_clock(rq);
- update_cpu_load_idle(rq);
+ cpu_load_update_idle(rq);
raw_spin_unlock_irq(&rq->lock);
rebalance_domains(rq, CPU_IDLE);
}
@@ -8382,6 +8525,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
init_cfs_rq(cfs_rq);
init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]);
init_entity_runnable_average(se);
+ post_init_entity_util_avg(se);
}
return 1;
@@ -8538,7 +8682,6 @@ const struct sched_class fair_sched_class = {
.rq_online = rq_online_fair,
.rq_offline = rq_offline_fair,
- .task_waking = task_waking_fair,
.task_dead = task_dead_fair,
.set_cpus_allowed = set_cpus_allowed_common,
#endif
@@ -8600,7 +8743,6 @@ __init void init_sched_fair_class(void)
#ifdef CONFIG_NO_HZ_COMMON
nohz.next_balance = jiffies;
zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
- cpu_notifier(sched_ilb_notifier, 0);
#endif
#endif /* SMP */
diff --git a/kernel/sched/idle_task.c b/kernel/sched/idle_task.c
index 47ce94931f1b..2ce5458bbe1d 100644
--- a/kernel/sched/idle_task.c
+++ b/kernel/sched/idle_task.c
@@ -24,7 +24,7 @@ static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int fl
}
static struct task_struct *
-pick_next_task_idle(struct rq *rq, struct task_struct *prev)
+pick_next_task_idle(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie)
{
put_prev_task(rq, prev);
diff --git a/kernel/sched/loadavg.c b/kernel/sched/loadavg.c
index ef7159012cf3..b0b93fd33af9 100644
--- a/kernel/sched/loadavg.c
+++ b/kernel/sched/loadavg.c
@@ -99,10 +99,13 @@ long calc_load_fold_active(struct rq *this_rq)
static unsigned long
calc_load(unsigned long load, unsigned long exp, unsigned long active)
{
- load *= exp;
- load += active * (FIXED_1 - exp);
- load += 1UL << (FSHIFT - 1);
- return load >> FSHIFT;
+ unsigned long newload;
+
+ newload = load * exp + active * (FIXED_1 - exp);
+ if (active >= load)
+ newload += FIXED_1-1;
+
+ return newload / FIXED_1;
}
#ifdef CONFIG_NO_HZ_COMMON
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index c41ea7ac1764..d5690b722691 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -334,7 +334,7 @@ static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
rt_rq = &rq_of_rt_rq(rt_rq)->rt;
rt_rq->rt_nr_total++;
- if (p->nr_cpus_allowed > 1)
+ if (tsk_nr_cpus_allowed(p) > 1)
rt_rq->rt_nr_migratory++;
update_rt_migration(rt_rq);
@@ -351,7 +351,7 @@ static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
rt_rq = &rq_of_rt_rq(rt_rq)->rt;
rt_rq->rt_nr_total--;
- if (p->nr_cpus_allowed > 1)
+ if (tsk_nr_cpus_allowed(p) > 1)
rt_rq->rt_nr_migratory--;
update_rt_migration(rt_rq);
@@ -953,14 +953,14 @@ static void update_curr_rt(struct rq *rq)
if (curr->sched_class != &rt_sched_class)
return;
- /* Kick cpufreq (see the comment in linux/cpufreq.h). */
- if (cpu_of(rq) == smp_processor_id())
- cpufreq_trigger_update(rq_clock(rq));
-
delta_exec = rq_clock_task(rq) - curr->se.exec_start;
if (unlikely((s64)delta_exec <= 0))
return;
+ /* Kick cpufreq (see the comment in linux/cpufreq.h). */
+ if (cpu_of(rq) == smp_processor_id())
+ cpufreq_trigger_update(rq_clock(rq));
+
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
@@ -1324,7 +1324,7 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
enqueue_rt_entity(rt_se, flags);
- if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
+ if (!task_current(rq, p) && tsk_nr_cpus_allowed(p) > 1)
enqueue_pushable_task(rq, p);
}
@@ -1413,7 +1413,7 @@ select_task_rq_rt(struct task_struct *p, int cpu, int sd_flag, int flags)
* will have to sort it out.
*/
if (curr && unlikely(rt_task(curr)) &&
- (curr->nr_cpus_allowed < 2 ||
+ (tsk_nr_cpus_allowed(curr) < 2 ||
curr->prio <= p->prio)) {
int target = find_lowest_rq(p);
@@ -1437,7 +1437,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
* Current can't be migrated, useless to reschedule,
* let's hope p can move out.
*/
- if (rq->curr->nr_cpus_allowed == 1 ||
+ if (tsk_nr_cpus_allowed(rq->curr) == 1 ||
!cpupri_find(&rq->rd->cpupri, rq->curr, NULL))
return;
@@ -1445,7 +1445,7 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
* p is migratable, so let's not schedule it and
* see if it is pushed or pulled somewhere else.
*/
- if (p->nr_cpus_allowed != 1
+ if (tsk_nr_cpus_allowed(p) != 1
&& cpupri_find(&rq->rd->cpupri, p, NULL))
return;
@@ -1524,7 +1524,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq)
}
static struct task_struct *
-pick_next_task_rt(struct rq *rq, struct task_struct *prev)
+pick_next_task_rt(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie)
{
struct task_struct *p;
struct rt_rq *rt_rq = &rq->rt;
@@ -1536,9 +1536,9 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev)
* disabled avoiding further scheduler activity on it and we're
* being very careful to re-start the picking loop.
*/
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, cookie);
pull_rt_task(rq);
- lockdep_pin_lock(&rq->lock);
+ lockdep_repin_lock(&rq->lock, cookie);
/*
* pull_rt_task() can drop (and re-acquire) rq->lock; this
* means a dl or stop task can slip in, in which case we need
@@ -1579,7 +1579,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
* The previous task needs to be made eligible for pushing
* if it is still active
*/
- if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1)
+ if (on_rt_rq(&p->rt) && tsk_nr_cpus_allowed(p) > 1)
enqueue_pushable_task(rq, p);
}
@@ -1629,7 +1629,7 @@ static int find_lowest_rq(struct task_struct *task)
if (unlikely(!lowest_mask))
return -1;
- if (task->nr_cpus_allowed == 1)
+ if (tsk_nr_cpus_allowed(task) == 1)
return -1; /* No other targets possible */
if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
@@ -1729,6 +1729,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
!cpumask_test_cpu(lowest_rq->cpu,
tsk_cpus_allowed(task)) ||
task_running(rq, task) ||
+ !rt_task(task) ||
!task_on_rq_queued(task))) {
double_unlock_balance(rq, lowest_rq);
@@ -1761,7 +1762,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
BUG_ON(rq->cpu != task_cpu(p));
BUG_ON(task_current(rq, p));
- BUG_ON(p->nr_cpus_allowed <= 1);
+ BUG_ON(tsk_nr_cpus_allowed(p) <= 1);
BUG_ON(!task_on_rq_queued(p));
BUG_ON(!rt_task(p));
@@ -2121,9 +2122,9 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
{
if (!task_running(rq, p) &&
!test_tsk_need_resched(rq->curr) &&
- p->nr_cpus_allowed > 1 &&
+ tsk_nr_cpus_allowed(p) > 1 &&
(dl_task(rq->curr) || rt_task(rq->curr)) &&
- (rq->curr->nr_cpus_allowed < 2 ||
+ (tsk_nr_cpus_allowed(rq->curr) < 2 ||
rq->curr->prio <= p->prio))
push_rt_tasks(rq);
}
@@ -2196,7 +2197,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
*/
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
- if (p->nr_cpus_allowed > 1 && rq->rt.overloaded)
+ if (tsk_nr_cpus_allowed(p) > 1 && rq->rt.overloaded)
queue_push_tasks(rq);
#else
if (p->prio < rq->curr->prio)
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index ec2e8d23527e..72f1f3087b04 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -31,9 +31,9 @@ extern void calc_global_load_tick(struct rq *this_rq);
extern long calc_load_fold_active(struct rq *this_rq);
#ifdef CONFIG_SMP
-extern void update_cpu_load_active(struct rq *this_rq);
+extern void cpu_load_update_active(struct rq *this_rq);
#else
-static inline void update_cpu_load_active(struct rq *this_rq) { }
+static inline void cpu_load_update_active(struct rq *this_rq) { }
#endif
/*
@@ -49,25 +49,32 @@ static inline void update_cpu_load_active(struct rq *this_rq) { }
* and does not change the user-interface for setting shares/weights.
*
* We increase resolution only if we have enough bits to allow this increased
- * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
- * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
- * increased costs.
+ * resolution (i.e. 64bit). The costs for increasing resolution when 32bit are
+ * pretty high and the returns do not justify the increased costs.
+ *
+ * Really only required when CONFIG_FAIR_GROUP_SCHED is also set, but to
+ * increase coverage and consistency always enable it on 64bit platforms.
*/
-#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */
-# define SCHED_LOAD_RESOLUTION 10
-# define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION)
-# define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION)
+#ifdef CONFIG_64BIT
+# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
+# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
+# define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT)
#else
-# define SCHED_LOAD_RESOLUTION 0
+# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
# define scale_load(w) (w)
# define scale_load_down(w) (w)
#endif
-#define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION)
-#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
-
-#define NICE_0_LOAD SCHED_LOAD_SCALE
-#define NICE_0_SHIFT SCHED_LOAD_SHIFT
+/*
+ * Task weight (visible to users) and its load (invisible to users) have
+ * independent resolution, but they should be well calibrated. We use
+ * scale_load() and scale_load_down(w) to convert between them. The
+ * following must be true:
+ *
+ * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
+ *
+ */
+#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
/*
* Single value that decides SCHED_DEADLINE internal math precision.
@@ -585,11 +592,13 @@ struct rq {
#endif
#define CPU_LOAD_IDX_MAX 5
unsigned long cpu_load[CPU_LOAD_IDX_MAX];
- unsigned long last_load_update_tick;
#ifdef CONFIG_NO_HZ_COMMON
+#ifdef CONFIG_SMP
+ unsigned long last_load_update_tick;
+#endif /* CONFIG_SMP */
u64 nohz_stamp;
unsigned long nohz_flags;
-#endif
+#endif /* CONFIG_NO_HZ_COMMON */
#ifdef CONFIG_NO_HZ_FULL
unsigned long last_sched_tick;
#endif
@@ -854,7 +863,7 @@ DECLARE_PER_CPU(struct sched_domain *, sd_asym);
struct sched_group_capacity {
atomic_t ref;
/*
- * CPU capacity of this group, SCHED_LOAD_SCALE being max capacity
+ * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
* for a single CPU.
*/
unsigned int capacity;
@@ -1159,7 +1168,7 @@ extern const u32 sched_prio_to_wmult[40];
*
* ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
* ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
- * ENQUEUE_WAKING - sched_class::task_waking was called
+ * ENQUEUE_MIGRATED - the task was migrated during wakeup
*
*/
@@ -1174,9 +1183,9 @@ extern const u32 sched_prio_to_wmult[40];
#define ENQUEUE_HEAD 0x08
#define ENQUEUE_REPLENISH 0x10
#ifdef CONFIG_SMP
-#define ENQUEUE_WAKING 0x20
+#define ENQUEUE_MIGRATED 0x20
#else
-#define ENQUEUE_WAKING 0x00
+#define ENQUEUE_MIGRATED 0x00
#endif
#define RETRY_TASK ((void *)-1UL)
@@ -1200,14 +1209,14 @@ struct sched_class {
* tasks.
*/
struct task_struct * (*pick_next_task) (struct rq *rq,
- struct task_struct *prev);
+ struct task_struct *prev,
+ struct pin_cookie cookie);
void (*put_prev_task) (struct rq *rq, struct task_struct *p);
#ifdef CONFIG_SMP
int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
void (*migrate_task_rq)(struct task_struct *p);
- void (*task_waking) (struct task_struct *task);
void (*task_woken) (struct rq *this_rq, struct task_struct *task);
void (*set_cpus_allowed)(struct task_struct *p,
@@ -1313,6 +1322,7 @@ extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
unsigned long to_ratio(u64 period, u64 runtime);
extern void init_entity_runnable_average(struct sched_entity *se);
+extern void post_init_entity_util_avg(struct sched_entity *se);
#ifdef CONFIG_NO_HZ_FULL
extern bool sched_can_stop_tick(struct rq *rq);
@@ -1448,86 +1458,32 @@ static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
static inline void sched_avg_update(struct rq *rq) { }
#endif
-/*
- * __task_rq_lock - lock the rq @p resides on.
- */
-static inline struct rq *__task_rq_lock(struct task_struct *p)
- __acquires(rq->lock)
-{
- struct rq *rq;
-
- lockdep_assert_held(&p->pi_lock);
-
- for (;;) {
- rq = task_rq(p);
- raw_spin_lock(&rq->lock);
- if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
- lockdep_pin_lock(&rq->lock);
- return rq;
- }
- raw_spin_unlock(&rq->lock);
-
- while (unlikely(task_on_rq_migrating(p)))
- cpu_relax();
- }
-}
+struct rq_flags {
+ unsigned long flags;
+ struct pin_cookie cookie;
+};
-/*
- * task_rq_lock - lock p->pi_lock and lock the rq @p resides on.
- */
-static inline struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
+struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
+ __acquires(rq->lock);
+struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
__acquires(p->pi_lock)
- __acquires(rq->lock)
-{
- struct rq *rq;
-
- for (;;) {
- raw_spin_lock_irqsave(&p->pi_lock, *flags);
- rq = task_rq(p);
- raw_spin_lock(&rq->lock);
- /*
- * move_queued_task() task_rq_lock()
- *
- * ACQUIRE (rq->lock)
- * [S] ->on_rq = MIGRATING [L] rq = task_rq()
- * WMB (__set_task_cpu()) ACQUIRE (rq->lock);
- * [S] ->cpu = new_cpu [L] task_rq()
- * [L] ->on_rq
- * RELEASE (rq->lock)
- *
- * If we observe the old cpu in task_rq_lock, the acquire of
- * the old rq->lock will fully serialize against the stores.
- *
- * If we observe the new cpu in task_rq_lock, the acquire will
- * pair with the WMB to ensure we must then also see migrating.
- */
- if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) {
- lockdep_pin_lock(&rq->lock);
- return rq;
- }
- raw_spin_unlock(&rq->lock);
- raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
+ __acquires(rq->lock);
- while (unlikely(task_on_rq_migrating(p)))
- cpu_relax();
- }
-}
-
-static inline void __task_rq_unlock(struct rq *rq)
+static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
__releases(rq->lock)
{
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, rf->cookie);
raw_spin_unlock(&rq->lock);
}
static inline void
-task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags)
+task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
__releases(rq->lock)
__releases(p->pi_lock)
{
- lockdep_unpin_lock(&rq->lock);
+ lockdep_unpin_lock(&rq->lock, rf->cookie);
raw_spin_unlock(&rq->lock);
- raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
+ raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
}
#ifdef CONFIG_SMP
@@ -1743,6 +1699,10 @@ enum rq_nohz_flag_bits {
};
#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
+
+extern void nohz_balance_exit_idle(unsigned int cpu);
+#else
+static inline void nohz_balance_exit_idle(unsigned int cpu) { }
#endif
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -1842,6 +1802,14 @@ static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned lo
static inline void cpufreq_trigger_update(u64 time) {}
#endif /* CONFIG_CPU_FREQ */
+#ifdef arch_scale_freq_capacity
+#ifndef arch_scale_freq_invariant
+#define arch_scale_freq_invariant() (true)
+#endif
+#else /* arch_scale_freq_capacity */
+#define arch_scale_freq_invariant() (false)
+#endif
+
static inline void account_reset_rq(struct rq *rq)
{
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index cbc67da10954..604297a08b3a 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -24,7 +24,7 @@ check_preempt_curr_stop(struct rq *rq, struct task_struct *p, int flags)
}
static struct task_struct *
-pick_next_task_stop(struct rq *rq, struct task_struct *prev)
+pick_next_task_stop(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie)
{
struct task_struct *stop = rq->stop;
diff --git a/kernel/signal.c b/kernel/signal.c
index aa9bf00749c1..ab122a2cee41 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3099,12 +3099,14 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
oss.ss_sp = (void __user *) current->sas_ss_sp;
oss.ss_size = current->sas_ss_size;
- oss.ss_flags = sas_ss_flags(sp);
+ oss.ss_flags = sas_ss_flags(sp) |
+ (current->sas_ss_flags & SS_FLAG_BITS);
if (uss) {
void __user *ss_sp;
size_t ss_size;
- int ss_flags;
+ unsigned ss_flags;
+ int ss_mode;
error = -EFAULT;
if (!access_ok(VERIFY_READ, uss, sizeof(*uss)))
@@ -3119,18 +3121,13 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
if (on_sig_stack(sp))
goto out;
+ ss_mode = ss_flags & ~SS_FLAG_BITS;
error = -EINVAL;
- /*
- * Note - this code used to test ss_flags incorrectly:
- * old code may have been written using ss_flags==0
- * to mean ss_flags==SS_ONSTACK (as this was the only
- * way that worked) - this fix preserves that older
- * mechanism.
- */
- if (ss_flags != SS_DISABLE && ss_flags != SS_ONSTACK && ss_flags != 0)
+ if (ss_mode != SS_DISABLE && ss_mode != SS_ONSTACK &&
+ ss_mode != 0)
goto out;
- if (ss_flags == SS_DISABLE) {
+ if (ss_mode == SS_DISABLE) {
ss_size = 0;
ss_sp = NULL;
} else {
@@ -3141,6 +3138,7 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
current->sas_ss_sp = (unsigned long) ss_sp;
current->sas_ss_size = ss_size;
+ current->sas_ss_flags = ss_flags;
}
error = 0;
@@ -3171,9 +3169,14 @@ int restore_altstack(const stack_t __user *uss)
int __save_altstack(stack_t __user *uss, unsigned long sp)
{
struct task_struct *t = current;
- return __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) |
- __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+ int err = __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) |
+ __put_user(t->sas_ss_flags, &uss->ss_flags) |
__put_user(t->sas_ss_size, &uss->ss_size);
+ if (err)
+ return err;
+ if (t->sas_ss_flags & SS_AUTODISARM)
+ sas_ss_reset(t);
+ return 0;
}
#ifdef CONFIG_COMPAT
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 725587f10667..c8b318663525 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -130,6 +130,9 @@ static int one_thousand = 1000;
#ifdef CONFIG_PRINTK
static int ten_thousand = 10000;
#endif
+#ifdef CONFIG_PERF_EVENTS
+static int six_hundred_forty_kb = 640 * 1024;
+#endif
/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
@@ -1144,6 +1147,15 @@ static struct ctl_table kern_table[] = {
.extra1 = &zero,
.extra2 = &one_hundred,
},
+ {
+ .procname = "perf_event_max_stack",
+ .data = NULL, /* filled in by handler */
+ .maxlen = sizeof(sysctl_perf_event_max_stack),
+ .mode = 0644,
+ .proc_handler = perf_event_max_stack_handler,
+ .extra1 = &zero,
+ .extra2 = &six_hundred_forty_kb,
+ },
#endif
#ifdef CONFIG_KMEMCHECK
{
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 58e3310c9b21..536ada80f6dd 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -262,7 +262,7 @@ static void tick_nohz_dep_set_all(atomic_t *dep,
{
int prev;
- prev = atomic_fetch_or(dep, BIT(bit));
+ prev = atomic_fetch_or(BIT(bit), dep);
if (!prev)
tick_nohz_full_kick_all();
}
@@ -292,7 +292,7 @@ void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit)
ts = per_cpu_ptr(&tick_cpu_sched, cpu);
- prev = atomic_fetch_or(&ts->tick_dep_mask, BIT(bit));
+ prev = atomic_fetch_or(BIT(bit), &ts->tick_dep_mask);
if (!prev) {
preempt_disable();
/* Perf needs local kick that is NMI safe */
@@ -776,6 +776,7 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
if (!ts->tick_stopped) {
nohz_balance_enter_idle(cpu);
calc_load_enter_idle();
+ cpu_load_update_nohz_start();
ts->last_tick = hrtimer_get_expires(&ts->sched_timer);
ts->tick_stopped = 1;
@@ -802,11 +803,11 @@ out:
return tick;
}
-static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now, int active)
+static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now)
{
/* Update jiffies first */
tick_do_update_jiffies64(now);
- update_cpu_load_nohz(active);
+ cpu_load_update_nohz_stop();
calc_load_exit_idle();
touch_softlockup_watchdog_sched();
@@ -833,7 +834,7 @@ static void tick_nohz_full_update_tick(struct tick_sched *ts)
if (can_stop_full_tick(ts))
tick_nohz_stop_sched_tick(ts, ktime_get(), cpu);
else if (ts->tick_stopped)
- tick_nohz_restart_sched_tick(ts, ktime_get(), 1);
+ tick_nohz_restart_sched_tick(ts, ktime_get());
#endif
}
@@ -1024,7 +1025,7 @@ void tick_nohz_idle_exit(void)
tick_nohz_stop_idle(ts, now);
if (ts->tick_stopped) {
- tick_nohz_restart_sched_tick(ts, now, 0);
+ tick_nohz_restart_sched_tick(ts, now);
tick_nohz_account_idle_ticks(ts);
}
diff --git a/kernel/time/time.c b/kernel/time/time.c
index be115b020d27..a4064b612066 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -160,15 +160,15 @@ static inline void warp_clock(void)
* various programs will get confused when the clock gets warped.
*/
-int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz)
+int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz)
{
static int firsttime = 1;
int error = 0;
- if (tv && !timespec_valid(tv))
+ if (tv && !timespec64_valid(tv))
return -EINVAL;
- error = security_settime(tv, tz);
+ error = security_settime64(tv, tz);
if (error)
return error;
@@ -186,7 +186,7 @@ int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz)
}
}
if (tv)
- return do_settimeofday(tv);
+ return do_settimeofday64(tv);
return 0;
}
diff --git a/kernel/torture.c b/kernel/torture.c
index 44aa462d033f..fa0bdeee17ac 100644
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -451,6 +451,7 @@ static int torture_shutdown(void *arg)
torture_shutdown_hook();
else
VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
+ ftrace_dump(DUMP_ALL);
kernel_power_off(); /* Shut down the system. */
return 0;
}
@@ -602,8 +603,9 @@ bool torture_init_begin(char *ttype, bool v, int *runnable)
{
mutex_lock(&fullstop_mutex);
if (torture_type != NULL) {
- pr_alert("torture_init_begin: refusing %s init: %s running",
+ pr_alert("torture_init_begin: Refusing %s init: %s running.\n",
ttype, torture_type);
+ pr_alert("torture_init_begin: One torture test at a time!\n");
mutex_unlock(&fullstop_mutex);
return false;
}
diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c
index 81b87451c0ea..0c7dee221dca 100644
--- a/kernel/trace/power-traces.c
+++ b/kernel/trace/power-traces.c
@@ -15,5 +15,6 @@
EXPORT_TRACEPOINT_SYMBOL_GPL(suspend_resume);
EXPORT_TRACEPOINT_SYMBOL_GPL(cpu_idle);
+EXPORT_TRACEPOINT_SYMBOL_GPL(cpu_frequency);
EXPORT_TRACEPOINT_SYMBOL_GPL(powernv_throttle);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 95181e36891a..9c143739b8d7 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -437,7 +437,7 @@ struct ring_buffer_per_cpu {
raw_spinlock_t reader_lock; /* serialize readers */
arch_spinlock_t lock;
struct lock_class_key lock_key;
- unsigned int nr_pages;
+ unsigned long nr_pages;
unsigned int current_context;
struct list_head *pages;
struct buffer_page *head_page; /* read from head */
@@ -458,7 +458,7 @@ struct ring_buffer_per_cpu {
u64 write_stamp;
u64 read_stamp;
/* ring buffer pages to update, > 0 to add, < 0 to remove */
- int nr_pages_to_update;
+ long nr_pages_to_update;
struct list_head new_pages; /* new pages to add */
struct work_struct update_pages_work;
struct completion update_done;
@@ -1128,10 +1128,10 @@ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer)
return 0;
}
-static int __rb_allocate_pages(int nr_pages, struct list_head *pages, int cpu)
+static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu)
{
- int i;
struct buffer_page *bpage, *tmp;
+ long i;
for (i = 0; i < nr_pages; i++) {
struct page *page;
@@ -1168,7 +1168,7 @@ free_pages:
}
static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
- unsigned nr_pages)
+ unsigned long nr_pages)
{
LIST_HEAD(pages);
@@ -1193,7 +1193,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
}
static struct ring_buffer_per_cpu *
-rb_allocate_cpu_buffer(struct ring_buffer *buffer, int nr_pages, int cpu)
+rb_allocate_cpu_buffer(struct ring_buffer *buffer, long nr_pages, int cpu)
{
struct ring_buffer_per_cpu *cpu_buffer;
struct buffer_page *bpage;
@@ -1293,8 +1293,9 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
struct lock_class_key *key)
{
struct ring_buffer *buffer;
+ long nr_pages;
int bsize;
- int cpu, nr_pages;
+ int cpu;
/* keep it in its own cache line */
buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()),
@@ -1420,12 +1421,12 @@ static inline unsigned long rb_page_write(struct buffer_page *bpage)
}
static int
-rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned int nr_pages)
+rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages)
{
struct list_head *tail_page, *to_remove, *next_page;
struct buffer_page *to_remove_page, *tmp_iter_page;
struct buffer_page *last_page, *first_page;
- unsigned int nr_removed;
+ unsigned long nr_removed;
unsigned long head_bit;
int page_entries;
@@ -1642,7 +1643,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
int cpu_id)
{
struct ring_buffer_per_cpu *cpu_buffer;
- unsigned nr_pages;
+ unsigned long nr_pages;
int cpu, err = 0;
/*
@@ -1656,14 +1657,13 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
!cpumask_test_cpu(cpu_id, buffer->cpumask))
return size;
- size = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
- size *= BUF_PAGE_SIZE;
+ nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
/* we need a minimum of two pages */
- if (size < BUF_PAGE_SIZE * 2)
- size = BUF_PAGE_SIZE * 2;
+ if (nr_pages < 2)
+ nr_pages = 2;
- nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
+ size = nr_pages * BUF_PAGE_SIZE;
/*
* Don't succeed if resizing is disabled, as a reader might be
@@ -4640,8 +4640,9 @@ static int rb_cpu_notify(struct notifier_block *self,
struct ring_buffer *buffer =
container_of(self, struct ring_buffer, cpu_notify);
long cpu = (long)hcpu;
- int cpu_i, nr_pages_same;
- unsigned int nr_pages;
+ long nr_pages_same;
+ int cpu_i;
+ unsigned long nr_pages;
switch (action) {
case CPU_UP_PREPARE:
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 00df25fd86ef..e11108f1d197 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -47,6 +47,9 @@ static int perf_trace_event_perm(struct trace_event_call *tp_event,
if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN))
return -EPERM;
+ if (!is_sampling_event(p_event))
+ return 0;
+
/*
* We don't allow user space callchains for function trace
* event, due to issues with page faults while tracing page
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 05ddc0820771..6f965864cc02 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2095,8 +2095,13 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file)
trace_create_file("filter", 0644, file->dir, file,
&ftrace_event_filter_fops);
- trace_create_file("trigger", 0644, file->dir, file,
- &event_trigger_fops);
+ /*
+ * Only event directories that can be enabled should have
+ * triggers.
+ */
+ if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
+ trace_create_file("trigger", 0644, file->dir, file,
+ &event_trigger_fops);
trace_create_file("format", 0444, file->dir, call,
&ftrace_event_format_fops);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 3bfdff06eea7..5f5068e94003 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4554,6 +4554,17 @@ static void rebind_workers(struct worker_pool *pool)
pool->attrs->cpumask) < 0);
spin_lock_irq(&pool->lock);
+
+ /*
+ * XXX: CPU hotplug notifiers are weird and can call DOWN_FAILED
+ * w/o preceding DOWN_PREPARE. Work around it. CPU hotplug is
+ * being reworked and this can go away in time.
+ */
+ if (!(pool->flags & POOL_DISASSOCIATED)) {
+ spin_unlock_irq(&pool->lock);
+ return;
+ }
+
pool->flags &= ~POOL_DISASSOCIATED;
for_each_pool_worker(worker, pool) {