diff options
| -rw-r--r-- | include/block/aio.h | 32 | ||||
| -rw-r--r-- | include/qemu/coroutine_int.h | 11 | ||||
| -rw-r--r-- | tests/Makefile.include | 8 | ||||
| -rw-r--r-- | tests/iothread.c | 91 | ||||
| -rw-r--r-- | tests/iothread.h | 25 | ||||
| -rw-r--r-- | tests/test-aio-multithread.c | 213 | ||||
| -rw-r--r-- | util/async.c | 65 | ||||
| -rw-r--r-- | util/qemu-coroutine.c | 8 | ||||
| -rw-r--r-- | util/trace-events | 4 |
9 files changed, 453 insertions, 4 deletions
diff --git a/include/block/aio.h b/include/block/aio.h index 7df271d2b9..614cbc6982 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -47,6 +47,7 @@ typedef void QEMUBHFunc(void *opaque); typedef bool AioPollFn(void *opaque); typedef void IOHandler(void *opaque); +struct Coroutine; struct ThreadPool; struct LinuxAioState; @@ -108,6 +109,9 @@ struct AioContext { bool notified; EventNotifier notifier; + QSLIST_HEAD(, Coroutine) scheduled_coroutines; + QEMUBH *co_schedule_bh; + /* Thread pool for performing work and receiving completion callbacks. * Has its own locking. */ @@ -483,6 +487,34 @@ static inline bool aio_node_check(AioContext *ctx, bool is_external) } /** + * aio_co_schedule: + * @ctx: the aio context + * @co: the coroutine + * + * Start a coroutine on a remote AioContext. + * + * The coroutine must not be entered by anyone else while aio_co_schedule() + * is active. In addition the coroutine must have yielded unless ctx + * is the context in which the coroutine is running (i.e. the value of + * qemu_get_current_aio_context() from the coroutine itself). + */ +void aio_co_schedule(AioContext *ctx, struct Coroutine *co); + +/** + * aio_co_wake: + * @co: the coroutine + * + * Restart a coroutine on the AioContext where it was running last, thus + * preventing coroutines from jumping from one context to another when they + * go to sleep. + * + * aio_co_wake may be executed either in coroutine or non-coroutine + * context. The coroutine must not be entered by anyone else while + * aio_co_wake() is active. + */ +void aio_co_wake(struct Coroutine *co); + +/** * Return the AioContext whose event loop runs in the current thread. * * If called from an IOThread this will be the IOThread's AioContext. If diff --git a/include/qemu/coroutine_int.h b/include/qemu/coroutine_int.h index 14d4f1d1f2..cb98892bba 100644 --- a/include/qemu/coroutine_int.h +++ b/include/qemu/coroutine_int.h @@ -40,12 +40,21 @@ struct Coroutine { CoroutineEntry *entry; void *entry_arg; Coroutine *caller; + + /* Only used when the coroutine has terminated. */ QSLIST_ENTRY(Coroutine) pool_next; + size_t locks_held; - /* Coroutines that should be woken up when we yield or terminate */ + /* Coroutines that should be woken up when we yield or terminate. + * Only used when the coroutine is running. + */ QSIMPLEQ_HEAD(, Coroutine) co_queue_wakeup; + + /* Only used when the coroutine has yielded. */ + AioContext *ctx; QSIMPLEQ_ENTRY(Coroutine) co_queue_next; + QSLIST_ENTRY(Coroutine) co_scheduled_next; }; Coroutine *qemu_coroutine_new(void); diff --git a/tests/Makefile.include b/tests/Makefile.include index fd9c70ab88..e60bb6ce58 100644 --- a/tests/Makefile.include +++ b/tests/Makefile.include @@ -48,9 +48,10 @@ check-unit-y += tests/test-aio$(EXESUF) gcov-files-test-aio-y = util/async.c util/qemu-timer.o gcov-files-test-aio-$(CONFIG_WIN32) += util/aio-win32.c gcov-files-test-aio-$(CONFIG_POSIX) += util/aio-posix.c +check-unit-y += tests/test-aio-multithread$(EXESUF) +gcov-files-test-aio-multithread-y = $(gcov-files-test-aio-y) +gcov-files-test-aio-multithread-y += util/qemu-coroutine.c tests/iothread.c check-unit-y += tests/test-throttle$(EXESUF) -gcov-files-test-aio-$(CONFIG_WIN32) = aio-win32.c -gcov-files-test-aio-$(CONFIG_POSIX) = aio-posix.c check-unit-y += tests/test-thread-pool$(EXESUF) gcov-files-test-thread-pool-y = thread-pool.c gcov-files-test-hbitmap-y = util/hbitmap.c @@ -508,7 +509,7 @@ test-qapi-obj-y = tests/test-qapi-visit.o tests/test-qapi-types.o \ $(test-qom-obj-y) test-crypto-obj-y = $(crypto-obj-y) $(test-qom-obj-y) test-io-obj-y = $(io-obj-y) $(test-crypto-obj-y) -test-block-obj-y = $(block-obj-y) $(test-io-obj-y) +test-block-obj-y = $(block-obj-y) $(test-io-obj-y) tests/iothread.o tests/check-qint$(EXESUF): tests/check-qint.o $(test-util-obj-y) tests/check-qstring$(EXESUF): tests/check-qstring.o $(test-util-obj-y) @@ -523,6 +524,7 @@ tests/check-qom-proplist$(EXESUF): tests/check-qom-proplist.o $(test-qom-obj-y) tests/test-char$(EXESUF): tests/test-char.o $(test-util-obj-y) $(qtest-obj-y) $(test-io-obj-y) $(chardev-obj-y) tests/test-coroutine$(EXESUF): tests/test-coroutine.o $(test-block-obj-y) tests/test-aio$(EXESUF): tests/test-aio.o $(test-block-obj-y) +tests/test-aio-multithread$(EXESUF): tests/test-aio-multithread.o $(test-block-obj-y) tests/test-throttle$(EXESUF): tests/test-throttle.o $(test-block-obj-y) tests/test-blockjob$(EXESUF): tests/test-blockjob.o $(test-block-obj-y) $(test-util-obj-y) tests/test-blockjob-txn$(EXESUF): tests/test-blockjob-txn.o $(test-block-obj-y) $(test-util-obj-y) diff --git a/tests/iothread.c b/tests/iothread.c new file mode 100644 index 0000000000..777d9eea46 --- /dev/null +++ b/tests/iothread.c @@ -0,0 +1,91 @@ +/* + * Event loop thread implementation for unit tests + * + * Copyright Red Hat Inc., 2013, 2016 + * + * Authors: + * Stefan Hajnoczi <stefanha@redhat.com> + * Paolo Bonzini <pbonzini@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "block/aio.h" +#include "qemu/main-loop.h" +#include "qemu/rcu.h" +#include "iothread.h" + +struct IOThread { + AioContext *ctx; + + QemuThread thread; + QemuMutex init_done_lock; + QemuCond init_done_cond; /* is thread initialization done? */ + bool stopping; +}; + +static __thread IOThread *my_iothread; + +AioContext *qemu_get_current_aio_context(void) +{ + return my_iothread ? my_iothread->ctx : qemu_get_aio_context(); +} + +static void *iothread_run(void *opaque) +{ + IOThread *iothread = opaque; + + rcu_register_thread(); + + my_iothread = iothread; + qemu_mutex_lock(&iothread->init_done_lock); + iothread->ctx = aio_context_new(&error_abort); + qemu_cond_signal(&iothread->init_done_cond); + qemu_mutex_unlock(&iothread->init_done_lock); + + while (!atomic_read(&iothread->stopping)) { + aio_poll(iothread->ctx, true); + } + + rcu_unregister_thread(); + return NULL; +} + +void iothread_join(IOThread *iothread) +{ + iothread->stopping = true; + aio_notify(iothread->ctx); + qemu_thread_join(&iothread->thread); + qemu_cond_destroy(&iothread->init_done_cond); + qemu_mutex_destroy(&iothread->init_done_lock); + aio_context_unref(iothread->ctx); + g_free(iothread); +} + +IOThread *iothread_new(void) +{ + IOThread *iothread = g_new0(IOThread, 1); + + qemu_mutex_init(&iothread->init_done_lock); + qemu_cond_init(&iothread->init_done_cond); + qemu_thread_create(&iothread->thread, NULL, iothread_run, + iothread, QEMU_THREAD_JOINABLE); + + /* Wait for initialization to complete */ + qemu_mutex_lock(&iothread->init_done_lock); + while (iothread->ctx == NULL) { + qemu_cond_wait(&iothread->init_done_cond, + &iothread->init_done_lock); + } + qemu_mutex_unlock(&iothread->init_done_lock); + return iothread; +} + +AioContext *iothread_get_aio_context(IOThread *iothread) +{ + return iothread->ctx; +} diff --git a/tests/iothread.h b/tests/iothread.h new file mode 100644 index 0000000000..4877cea6a3 --- /dev/null +++ b/tests/iothread.h @@ -0,0 +1,25 @@ +/* + * Event loop thread implementation for unit tests + * + * Copyright Red Hat Inc., 2013, 2016 + * + * Authors: + * Stefan Hajnoczi <stefanha@redhat.com> + * Paolo Bonzini <pbonzini@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ +#ifndef TEST_IOTHREAD_H +#define TEST_IOTHREAD_H + +#include "block/aio.h" +#include "qemu/thread.h" + +typedef struct IOThread IOThread; + +IOThread *iothread_new(void); +void iothread_join(IOThread *iothread); +AioContext *iothread_get_aio_context(IOThread *iothread); + +#endif diff --git a/tests/test-aio-multithread.c b/tests/test-aio-multithread.c new file mode 100644 index 0000000000..534807d45b --- /dev/null +++ b/tests/test-aio-multithread.c @@ -0,0 +1,213 @@ +/* + * AioContext multithreading tests + * + * Copyright Red Hat, Inc. 2016 + * + * Authors: + * Paolo Bonzini <pbonzini@redhat.com> + * + * This work is licensed under the terms of the GNU LGPL, version 2 or later. + * See the COPYING.LIB file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include <glib.h> +#include "block/aio.h" +#include "qapi/error.h" +#include "qemu/coroutine.h" +#include "qemu/thread.h" +#include "qemu/error-report.h" +#include "iothread.h" + +/* AioContext management */ + +#define NUM_CONTEXTS 5 + +static IOThread *threads[NUM_CONTEXTS]; +static AioContext *ctx[NUM_CONTEXTS]; +static __thread int id = -1; + +static QemuEvent done_event; + +/* Run a function synchronously on a remote iothread. */ + +typedef struct CtxRunData { + QEMUBHFunc *cb; + void *arg; +} CtxRunData; + +static void ctx_run_bh_cb(void *opaque) +{ + CtxRunData *data = opaque; + + data->cb(data->arg); + qemu_event_set(&done_event); +} + +static void ctx_run(int i, QEMUBHFunc *cb, void *opaque) +{ + CtxRunData data = { + .cb = cb, + .arg = opaque + }; + + qemu_event_reset(&done_event); + aio_bh_schedule_oneshot(ctx[i], ctx_run_bh_cb, &data); + qemu_event_wait(&done_event); +} + +/* Starting the iothreads. */ + +static void set_id_cb(void *opaque) +{ + int *i = opaque; + + id = *i; +} + +static void create_aio_contexts(void) +{ + int i; + + for (i = 0; i < NUM_CONTEXTS; i++) { + threads[i] = iothread_new(); + ctx[i] = iothread_get_aio_context(threads[i]); + } + + qemu_event_init(&done_event, false); + for (i = 0; i < NUM_CONTEXTS; i++) { + ctx_run(i, set_id_cb, &i); + } +} + +/* Stopping the iothreads. */ + +static void join_aio_contexts(void) +{ + int i; + + for (i = 0; i < NUM_CONTEXTS; i++) { + aio_context_ref(ctx[i]); + } + for (i = 0; i < NUM_CONTEXTS; i++) { + iothread_join(threads[i]); + } + for (i = 0; i < NUM_CONTEXTS; i++) { + aio_context_unref(ctx[i]); + } + qemu_event_destroy(&done_event); +} + +/* Basic test for the stuff above. */ + +static void test_lifecycle(void) +{ + create_aio_contexts(); + join_aio_contexts(); +} + +/* aio_co_schedule test. */ + +static Coroutine *to_schedule[NUM_CONTEXTS]; + +static bool now_stopping; + +static int count_retry; +static int count_here; +static int count_other; + +static bool schedule_next(int n) +{ + Coroutine *co; + + co = atomic_xchg(&to_schedule[n], NULL); + if (!co) { + atomic_inc(&count_retry); + return false; + } + + if (n == id) { + atomic_inc(&count_here); + } else { + atomic_inc(&count_other); + } + + aio_co_schedule(ctx[n], co); + return true; +} + +static void finish_cb(void *opaque) +{ + schedule_next(id); +} + +static coroutine_fn void test_multi_co_schedule_entry(void *opaque) +{ + g_assert(to_schedule[id] == NULL); + atomic_mb_set(&to_schedule[id], qemu_coroutine_self()); + + while (!atomic_mb_read(&now_stopping)) { + int n; + + n = g_test_rand_int_range(0, NUM_CONTEXTS); + schedule_next(n); + qemu_coroutine_yield(); + + g_assert(to_schedule[id] == NULL); + atomic_mb_set(&to_schedule[id], qemu_coroutine_self()); + } +} + + +static void test_multi_co_schedule(int seconds) +{ + int i; + + count_here = count_other = count_retry = 0; + now_stopping = false; + + create_aio_contexts(); + for (i = 0; i < NUM_CONTEXTS; i++) { + Coroutine *co1 = qemu_coroutine_create(test_multi_co_schedule_entry, NULL); + aio_co_schedule(ctx[i], co1); + } + + g_usleep(seconds * 1000000); + + atomic_mb_set(&now_stopping, true); + for (i = 0; i < NUM_CONTEXTS; i++) { + ctx_run(i, finish_cb, NULL); + to_schedule[i] = NULL; + } + + join_aio_contexts(); + g_test_message("scheduled %d, queued %d, retry %d, total %d\n", + count_other, count_here, count_retry, + count_here + count_other + count_retry); +} + +static void test_multi_co_schedule_1(void) +{ + test_multi_co_schedule(1); +} + +static void test_multi_co_schedule_10(void) +{ + test_multi_co_schedule(10); +} + +/* End of tests. */ + +int main(int argc, char **argv) +{ + init_clocks(); + + g_test_init(&argc, &argv, NULL); + g_test_add_func("/aio/multi/lifecycle", test_lifecycle); + if (g_test_quick()) { + g_test_add_func("/aio/multi/schedule", test_multi_co_schedule_1); + } else { + g_test_add_func("/aio/multi/schedule", test_multi_co_schedule_10); + } + return g_test_run(); +} diff --git a/util/async.c b/util/async.c index 1fd97e1f15..9cac702c5b 100644 --- a/util/async.c +++ b/util/async.c @@ -31,6 +31,8 @@ #include "qemu/main-loop.h" #include "qemu/atomic.h" #include "block/raw-aio.h" +#include "qemu/coroutine_int.h" +#include "trace.h" /***********************************************************/ /* bottom halves (can be seen as timers which expire ASAP) */ @@ -275,6 +277,9 @@ aio_ctx_finalize(GSource *source) } #endif + assert(QSLIST_EMPTY(&ctx->scheduled_coroutines)); + qemu_bh_delete(ctx->co_schedule_bh); + qemu_lockcnt_lock(&ctx->list_lock); assert(!qemu_lockcnt_count(&ctx->list_lock)); while (ctx->first_bh) { @@ -364,6 +369,28 @@ static bool event_notifier_poll(void *opaque) return atomic_read(&ctx->notified); } +static void co_schedule_bh_cb(void *opaque) +{ + AioContext *ctx = opaque; + QSLIST_HEAD(, Coroutine) straight, reversed; + + QSLIST_MOVE_ATOMIC(&reversed, &ctx->scheduled_coroutines); + QSLIST_INIT(&straight); + + while (!QSLIST_EMPTY(&reversed)) { + Coroutine *co = QSLIST_FIRST(&reversed); + QSLIST_REMOVE_HEAD(&reversed, co_scheduled_next); + QSLIST_INSERT_HEAD(&straight, co, co_scheduled_next); + } + + while (!QSLIST_EMPTY(&straight)) { + Coroutine *co = QSLIST_FIRST(&straight); + QSLIST_REMOVE_HEAD(&straight, co_scheduled_next); + trace_aio_co_schedule_bh_cb(ctx, co); + qemu_coroutine_enter(co); + } +} + AioContext *aio_context_new(Error **errp) { int ret; @@ -379,6 +406,10 @@ AioContext *aio_context_new(Error **errp) } g_source_set_can_recurse(&ctx->source, true); qemu_lockcnt_init(&ctx->list_lock); + + ctx->co_schedule_bh = aio_bh_new(ctx, co_schedule_bh_cb, ctx); + QSLIST_INIT(&ctx->scheduled_coroutines); + aio_set_event_notifier(ctx, &ctx->notifier, false, (EventNotifierHandler *) @@ -402,6 +433,40 @@ fail: return NULL; } +void aio_co_schedule(AioContext *ctx, Coroutine *co) +{ + trace_aio_co_schedule(ctx, co); + QSLIST_INSERT_HEAD_ATOMIC(&ctx->scheduled_coroutines, + co, co_scheduled_next); + qemu_bh_schedule(ctx->co_schedule_bh); +} + +void aio_co_wake(struct Coroutine *co) +{ + AioContext *ctx; + + /* Read coroutine before co->ctx. Matches smp_wmb in + * qemu_coroutine_enter. + */ + smp_read_barrier_depends(); + ctx = atomic_read(&co->ctx); + + if (ctx != qemu_get_current_aio_context()) { + aio_co_schedule(ctx, co); + return; + } + + if (qemu_in_coroutine()) { + Coroutine *self = qemu_coroutine_self(); + assert(self != co); + QSIMPLEQ_INSERT_TAIL(&self->co_queue_wakeup, co, co_queue_next); + } else { + aio_context_acquire(ctx); + qemu_coroutine_enter(co); + aio_context_release(ctx); + } +} + void aio_context_ref(AioContext *ctx) { g_source_ref(&ctx->source); diff --git a/util/qemu-coroutine.c b/util/qemu-coroutine.c index a5d2f6c0c3..415600dc30 100644 --- a/util/qemu-coroutine.c +++ b/util/qemu-coroutine.c @@ -19,6 +19,7 @@ #include "qemu/atomic.h" #include "qemu/coroutine.h" #include "qemu/coroutine_int.h" +#include "block/aio.h" enum { POOL_BATCH_SIZE = 64, @@ -114,6 +115,13 @@ void qemu_coroutine_enter(Coroutine *co) } co->caller = self; + co->ctx = qemu_get_current_aio_context(); + + /* Store co->ctx before anything that stores co. Matches + * barrier in aio_co_wake. + */ + smp_wmb(); + ret = qemu_coroutine_switch(self, co, COROUTINE_ENTER); qemu_co_queue_run_restart(co); diff --git a/util/trace-events b/util/trace-events index 1fa12f0491..53bd70c4cd 100644 --- a/util/trace-events +++ b/util/trace-events @@ -6,6 +6,10 @@ run_poll_handlers_end(void *ctx, bool progress) "ctx %p progress %d" poll_shrink(void *ctx, int64_t old, int64_t new) "ctx %p old %"PRId64" new %"PRId64 poll_grow(void *ctx, int64_t old, int64_t new) "ctx %p old %"PRId64" new %"PRId64 +# util/async.c +aio_co_schedule(void *ctx, void *co) "ctx %p co %p" +aio_co_schedule_bh_cb(void *ctx, void *co) "ctx %p co %p" + # util/thread-pool.c thread_pool_submit(void *pool, void *req, void *opaque) "pool %p req %p opaque %p" thread_pool_complete(void *pool, void *req, void *opaque, int ret) "pool %p req %p opaque %p ret %d" |