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2014-08-07monitor: Add drift info to 'info jit'Sebastian Tanase1-0/+19
Show in 'info jit' the current delay between the host clock and the guest clock. In addition, print the maximum advance and delay of the guest compared to the host. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06cpu-exec: Add sleeping algorithmSebastian Tanase1-0/+17
The goal is to sleep qemu whenever the guest clock is in advance compared to the host clock (we use the monotonic clocks). The amount of time to sleep is calculated in the execution loop in cpu_exec. At first, we tried to approximate at each for loop the real time elapsed while searching for a TB (generating or retrieving from cache) and executing it. We would then approximate the virtual time corresponding to the number of virtual instructions executed. The difference between these 2 values would allow us to know if the guest is in advance or delayed. However, the function used for measuring the real time (qemu_clock_get_ns(QEMU_CLOCK_REALTIME)) proved to be very expensive. We had an added overhead of 13% of the total run time. Therefore, we modified the algorithm and only take into account the difference between the 2 clocks at the begining of the cpu_exec function. During the for loop we try to reduce the advance of the guest only by computing the virtual time elapsed and sleeping if necessary. The overhead is thus reduced to 3%. Even though this method still has a noticeable overhead, it no longer is a bottleneck in trying to achieve a better guest frequency for which the guest clock is faster than the host one. As for the the alignement of the 2 clocks, with the first algorithm the guest clock was oscillating between -1 and 1ms compared to the host clock. Using the second algorithm we notice that the guest is 5ms behind the host, which is still acceptable for our use case. The tests where conducted using fio and stress. The host machine in an i5 CPU at 3.10GHz running Debian Jessie (kernel 3.12). The guest machine is an arm versatile-pb built with buildroot. Currently, on our test machine, the lowest icount we can achieve that is suitable for aligning the 2 clocks is 6. However, we observe that the IO tests (using fio) are slower than the cpu tests (using stress). Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: Add align option to icountSebastian Tanase1-7/+12
The align option is used for activating the align algorithm in order to synchronise the host clock and the guest clock. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: Add QemuOpts for icountSebastian Tanase1-1/+9
Make icount parameter use QemuOpts style options in order to easily add other suboptions. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Tested-by: Camille Bégué <camille.begue@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: Fix virtual clock start value on ARMSebastian Tanase1-1/+1
When using the icount option on ARM, the virtual clock starts counting at realtime clock but it should start at 0. The reason why the virtual clock starts at realtime clock is because the first time we call qemu_clock_warp (which calls icount_warp_rt) in tcg_exec_all, qemu_icount_bias (which is part of the virtual time computation mechanism) will increment by realtime - vm_clock_warp_start, with vm_clock_warp_start being 0 (see icount_warp_rt in cpus.c). By changing the value of vm_clock_warp_start from 0 to -1, the first time we call qemu_clock_warp which calls icount_warp_rt, we will return immediatly because icount_warp_rt first checks if vm_clock_warp_start is -1 and if it's the case it returns. Therefore, qemu_icount_bias will first be incremented by the value of a virtual timer deadline when the virtual cpu goes from active to inactive. The virtual time will start at 0 and increment based on the instruction counter when the vcpu is active or the qemu_icount_bias value when inactive. Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06timer: add cpu_icount_to_ns function.KONRAD Frederic1-1/+6
This adds cpu_icount_to_ns function which is needed for reverse execution. It returns the time for a specific instruction. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06migration: migrate icount fields.KONRAD Frederic1-0/+27
This fixes a bug where qemu_icount and qemu_icount_bias are not migrated. It adds a subsection "timer/icount" to vmstate_timers so icount is migrated only when needed. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Reviewed-by: Amit Shah <amit.shah@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06icount: put icount variables into TimerState.KONRAD Frederic1-13/+16
This puts qemu_icount and qemu_icount_bias into TimerState structure to allow them to be migrated. Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-23qapi event: convert STOPWenchao Xia1-1/+3
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-23vl: allow other threads to do qemu_system_vmstop_requestPaolo Bonzini1-0/+1
There patch protects vmstop_requested with a lock and introduces qemu_system_vmstop_request_prepare. Together with the new call to qemu_vmstop_requested in vm_start, qemu_system_vmstop_request_prepare avoids a race where the VM could remain stopped even though the iostatus of a block device has already been set (for example). qemu_system_vmstop_request_prepare however also lets the caller thread delay observation of the state change until it has itself communicated that change to the user. This delay avoids any possibility of a wrong reordering of the BLOCK_IO_ERROR event and the subsequent STOP event. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-19NUMA: move numa related code to new file numa.cWanlong Gao1-14/+0
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com> Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> MST: comment tweaks
2014-06-17qtest: fix qtest_clock_warp() for no deadline caseSergey Fedorov1-1/+1
Use dedicated qemu_soonest_timeout() instead of MIN(). Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-05-14savevm: Remove all the unneeded version_minimum_id_old (rest)Juan Quintela1-2/+1
After previous Peter patch, they are redundant. This way we don't assign them except when needed. Once there, there were lots of case where the ".fields" indentation was wrong: .fields = (VMStateField []) { and .fields = (VMStateField []) { Change all the combinations to: .fields = (VMStateField[]){ The biggest problem (appart from aesthetics) was that checkpatch complained when we copy&pasted the code from one place to another. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2014-04-27misc: Use cpu_physical_memory_read and cpu_physical_memory_writeStefan Weil1-1/+1
These functions don't need type casts (as does cpu_physical_memory_rw) and also make the code better readable. Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-03-13cpu: Move icount_decr field from CPU_COMMON to CPUStateAndreas Färber1-7/+6
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13cpu: Move icount_extra field from CPU_COMMON to CPUStateAndreas Färber1-7/+7
Reset it. Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13cpu: Move can_do_io field from CPU_COMMON to CPUStateAndreas Färber1-1/+1
Rename can_do_io() to cpu_can_do_io() and change argument to CPUState. Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13cpu: Turn cpu_has_work() into a CPUClass hookAndreas Färber1-1/+1
Default to false. Tidy variable naming and inline cast uses while at it. Tested-by: Jia Liu <proljc@gmail.com> (or32) Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-09Add a 'name' parameter to qemu_thread_createDr. David Alan Gilbert1-5/+20
If enabled, set the thread name at creation (on GNU systems with pthread_set_np) Fix up all the callers with a thread name Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2014-02-11cpu: Add per-cpu address spaceEdgar E. Iglesias1-0/+2
Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2013-12-23target-i386: Move apic_state field from CPUX86State to X86CPUChen Fan1-3/+2
This motion is preparing for refactoring vCPU APIC subsequently. Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-11-06timers: fix stop/cont with -icountPaolo Bonzini1-20/+22
Stop/cont commands are broken with -icount due to a deadlock. The real problem is that the computation of timers_state.cpu_ticks_offset makes no sense with -icount enabled: we set it to an icount clock value in cpu_disable_ticks, and subtract a TSC (or similar, whatever cpu_get_real_ticks happens to return) value in cpu_enable_ticks. The fix is simple. timers_state.cpu_ticks_offset is only used together with cpu_get_real_ticks, so we can use cpu_get_real_ticks in cpu_disable_ticks. There is no need to update cpu_ticks_prev at the time cpu_disable_ticks is called; instead, we can do it the next time cpu_get_ticks is called. The change to cpu_disable_ticks is the important part of the patch. The rest modifies the code to always check timers_state.cpu_ticks_prev, even when the ticks are not advancing (i.e. the VM is stopped). It also makes a similar change to cpu_get_clock_locked, so that the code remains similar for cpu_get_ticks and cpu_get_clock_locked. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1382977938-13844-1-git-send-email-pbonzini@redhat.com Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2013-10-25target-ppc: Check for error on address translation in memsave commandAneesh Kumar K.V1-1/+4
When we translate the virtual address to physical check for error. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17icount: make it thread-safePaolo Bonzini1-6/+31
This lets threads other than the I/O thread use vm_clock even in -icount mode. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-17icount: document (future) locking rules for icountPaolo Bonzini1-4/+11
Reviewed-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-17icount: prepare the code for future races in calling qemu_clock_warpPaolo Bonzini1-12/+10
Computing the deadline of all vm_clocks is somewhat expensive and calls out to qemu-timer.c; two reasons not to do it in the seqlock's write-side critical section. This however opens the door for races in setting and reading vm_clock_warp_start. To plug them, we need to cover the case where a new deadline slips in between the call to qemu_clock_deadline_ns_all and the actual modification of the icount_warp_timer. Restrict changes to vm_clock_warp_start and the icount_warp_timer's expiration time, to only move them back (which would simply cause an early wakeup). If a vm_clock timer is cancelled while CPUs are idle, this might cause the icount_warp_timer to fire unnecessarily. This is not a problem, after it fires the timer becomes inactive and the next call to timer_mod_anticipate will be precise. In addition to this, we must deactivate the icount_warp_timer _before_ checking whether CPUs are idle. This way, if the "last" CPU becomes idle during the call to timer_del we will still set up the icount_warp_timer. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-17icount: reorganize icount_warp_rtPaolo Bonzini1-8/+10
To prepare for future code changes, move the increment of qemu_icount_bias outside the "if" statement. Also, hoist outside the if the check for timers that expired due to the "warping". The check is redundant when !runstate_is_running(), but doing it this way helps because the code that increments qemu_icount_bias will be a critical section. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-17icount: use cpu_get_icount() directlyPaolo Bonzini1-2/+5
This will help later when we will have to place these calls in a critical section, and thus call a version of cpu_get_icount() that does not take the lock. Reviewed-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-17timer: protect timers_state's clock with seqlockLiu Ping Fan1-7/+42
QEMU_CLOCK_VIRTUAL may be read outside BQL. This will make its foundation, i.e. cpu_clock_offset exposed to race condition. Using private lock to protect it. After this patch, reading QEMU_CLOCK_VIRTUAL is thread safe unless use_icount is true, in which case the existing callers still rely on the BQL. Lock rule: private lock innermost, ie BQL->"this lock" Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-03cpu: Replace qemu_for_each_cpu()Andreas Färber1-7/+4
It was introduced to loop over CPUs from target-independent code, but since commit 182735efaf956ccab50b6d74a4fed163e0f35660 target-independent CPUState is used. A loop can be considered more efficient than function calls in a loop, and CPU_FOREACH() hides implementation details just as well, so use that instead. Suggested-by: Markus Armbruster <armbru@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-09-03cpu: Use QTAILQ for CPU listAndreas Färber1-28/+21
Introduce CPU_FOREACH(), CPU_FOREACH_SAFE() and CPU_NEXT() shorthand macros. Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-08-30s390: wire up nmi command to raise a RESTART interrupt on S390Eugene (jno) Dvurechenski1-0/+14
There is the 'nmi' command that is used to trigger a guest dump via kdump feature on x86. s390 uses RESTART interrupt to trigger kdump. So, this patch provides a mean to use 'nmi' command on s390 to raise RESTART interrupt. The CPU to receive the RESTART interrupt is the "default" one. There is an infrastructure to select the "default" CPU using 'cpu' command. The 'info cpus' command can be used to see which one is the "default". In order to wire up the RESTART to 'nmi' command we had to: 1. implement the kvm_s390_cpu_restart function by exporting the existing code 2. implement s390_cpu_restart function as kvm-aware wrapper 3. modify the qmp_inject_nmi function to enable (for s390) the scan for "default" CPU and call s390_cpu_restart for it; 3. fix some messages. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Alexander Graf <agraf@suse.de>
2013-08-22aio / timers: Rearrange timer.h & make legacy functions call non-legacyAlex Bligh1-53/+59
Rearrange timer.h so it is in order by function type. Make legacy functions call non-legacy functions rather than vice-versa. Convert cpus.c to use new API. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22aio / timers: Use all timerlists in icount warp calculationsAlex Bligh1-9/+37
Notify all timerlists derived from vm_clock in icount warp calculations. When calculating timer delay based on vm_clock deadline, use all timerlists. For compatibility, maintain an apparent bug where when using icount, if no vm_clock timer was set, qemu_clock_deadline would return INT32_MAX and always set an icount clock expiry about 2 seconds ahead. NB: thread safety - when different timerlists sit on different threads, this will need some locking. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-16cpus: Use cpu_is_stopped() efficientlyTiejun Chen1-7/+7
It makes more sense and will make things simpler later. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-27timer: make timers_state staticLiu Ping Fan1-1/+1
Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-07-23exec: Change cpu_memory_rw_debug() argument to CPUStateAndreas Färber1-3/+1
Propagate X86CPU in kvmvapic for simplicity. Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-23cpu: Move singlestep_enabled field from CPU_COMMON to CPUStateAndreas Färber1-1/+1
Prepares for changing cpu_single_step() argument to CPUState. Acked-by: Michael Walle <michael@walle.cc> (for lm32) Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-19cpus: Let vm_stop[_force_state]() always flush block devicesKevin Wolf1-3/+6
Even if the VM is already stopped, we cannot assume that all data has already been successfully flushed to disk. The flush during the previous vm_stop() could have failed. Run bdrv_flush_all() unconditionally so that we get an error each time if the block device isn't really flushed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-15Merge remote-tracking branch 'quintela/migration.next' into stagingAnthony Liguori1-0/+29
# By Chegu Vinod # Via Juan Quintela * quintela/migration.next: Force auto-convegence of live migration Add 'auto-converge' migration capability Introduce async_run_on_cpu() Message-id: 1373664508-5404-1-git-send-email-quintela@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-07-15cpus: Add return value for vm_stop()Kevin Wolf1-7/+13
If flushing the block devices fails, return an error. The VM is stopped anyway. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-12Introduce async_run_on_cpu()Chegu Vinod1-0/+29
Introduce an asynchronous version of run_on_cpu() i.e. the caller doesn't have to block till the call back routine finishes execution on the target vcpu. Signed-off-by: Chegu Vinod <chegu_vinod@hp.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-07-09cpu: Make first_cpu and next_cpu CPUStateAndreas Färber1-60/+66
Move next_cpu from CPU_COMMON to CPUState. Move first_cpu variable to qom/cpu.h. gdbstub needs to use CPUState::env_ptr for now. cpu_copy() no longer needs to save and restore cpu_next. Acked-by: Paolo Bonzini <pbonzini@redhat.com> [AF: Rebased, simplified cpu_copy()] Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-09cpu: Replace cpu_single_env with CPUState current_cpuAndreas Färber1-21/+20
Move it to qom/cpu.h. Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-01KVM: Don't assume that mpstate exists with in-kernel PIC alwaysAlexander Graf1-1/+1
On PPC, we don't support MP state. So far it's not necessary and I'm not convinced yet that we really need to support it ever. However, the current idle logic in QEMU assumes that an in-kernel PIC also means we support MP state. This assumption is not true anymore. Let's split up the two cases into two different variables. That way PPC can expose an in-kernel PIC, while not implementing MP state. Signed-off-by: Alexander Graf <agraf@suse.de> CC: Jan Kiszka <jan.kiszka@siemens.com>
2013-06-28cpu: Change qemu_init_vcpu() argument to CPUStateAndreas Färber1-4/+1
This allows to move the call into CPUState's realizefn. Therefore move the stub into libqemustub.a. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-06-28cpus: Change qemu_dummy_start_vcpu() argument to CPUStateAndreas Färber1-9/+6
Pass it to qemu_dummy_cpu_thread_fn(). Use CPUState::env_ptr for cpu_single_env. Prepares for changing qemu_init_vcpu() argument to CPUState. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-06-28cpus: Change qemu_kvm_start_vcpu() argument to CPUStateAndreas Färber1-8/+5
Pass it on to qemu_kvm_cpu_thread_fn(). Prepares for changing qemu_init_vcpu() argument to CPUState. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-06-28cpus: Change cpu_handle_guest_debug() argument to CPUStateAndreas Färber1-5/+3
CPUArchState is no longer needed. Prepares for changing qemu_kvm_cpu_thread_fn() opaque to CPUState. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-06-28gdbstub: Set gdb_set_stop_cpu() argument to CPUStateAndreas Färber1-1/+1
Use CPUState::env_ptr for now. Prepares for changing cpu_handle_guest_debug() argument to CPUState. Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Andreas Färber <afaerber@suse.de>