* [PATCH 0/3] perf: Fixes on event accounting
@ 2013-08-02 16:29 Frederic Weisbecker
2013-08-02 16:29 ` [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex Frederic Weisbecker
` (2 more replies)
0 siblings, 3 replies; 9+ messages in thread
From: Frederic Weisbecker @ 2013-08-02 16:29 UTC (permalink / raw)
To: Peter Zijlstra, Jiri Olsa
Cc: LKML, Frederic Weisbecker, Steven Rostedt, Paul E. McKenney,
Ingo Molnar, Thomas Gleixner, Borislav Petkov, Li Zhong,
Mike Galbraith, Kevin Hilman, Namhyung Kim,
Arnaldo Carvalho de Melo, Stephane Eranian
Peter, Jiri,
Here is a proposed set of fixes after the discussion we had about the
last changes in the event accounting code.
Thanks,
Frederic
---
Frederic Weisbecker (3):
perf: Rollback callchain buffer refcount under the callchain mutex
perf: Account freq events globally
nohz: Include local CPU in full dynticks global kick
kernel/events/callchain.c | 3 ++-
kernel/events/core.c | 19 ++++++++-----------
kernel/time/tick-sched.c | 1 +
3 files changed, 11 insertions(+), 12 deletions(-)
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex 2013-08-02 16:29 [PATCH 0/3] perf: Fixes on event accounting Frederic Weisbecker @ 2013-08-02 16:29 ` Frederic Weisbecker 2013-08-09 10:28 ` Jiri Olsa 2013-08-16 18:47 ` [tip:perf/core] perf: Roll back " tip-bot for Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 2/3] perf: Account freq events globally Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 3/3] nohz: Include local CPU in full dynticks global kick Frederic Weisbecker 2 siblings, 2 replies; 9+ messages in thread From: Frederic Weisbecker @ 2013-08-02 16:29 UTC (permalink / raw) To: Peter Zijlstra, Jiri Olsa Cc: LKML, Frederic Weisbecker, Ingo Molnar, Namhyung Kim, Arnaldo Carvalho de Melo, Stephane Eranian When we fail to allocate the callchain buffers, we rollback the refcount we did and return from get_callchain_buffers(). However we take the refcount and allocate under the callchain lock but the rollback is done outside the lock. As a result, while we rollback, some concurrent callchain user may call get_callchain_buffers(), see the non-zero refcount and give up because the buffers are NULL without itself retrying the allocation. The consequences aren't that bad but that behaviour looks weird enough and it's better to give their chances to the following callchain users where we failed. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Stephane Eranian <eranian@google.com> --- kernel/events/callchain.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 76a8bc5..97b67df 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -116,10 +116,11 @@ int get_callchain_buffers(void) err = alloc_callchain_buffers(); exit: - mutex_unlock(&callchain_mutex); if (err) atomic_dec(&nr_callchain_events); + mutex_unlock(&callchain_mutex); + return err; } -- 1.7.5.4 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex 2013-08-02 16:29 ` [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex Frederic Weisbecker @ 2013-08-09 10:28 ` Jiri Olsa 2013-08-16 18:47 ` [tip:perf/core] perf: Roll back " tip-bot for Frederic Weisbecker 1 sibling, 0 replies; 9+ messages in thread From: Jiri Olsa @ 2013-08-09 10:28 UTC (permalink / raw) To: Frederic Weisbecker Cc: Peter Zijlstra, LKML, Ingo Molnar, Namhyung Kim, Arnaldo Carvalho de Melo, Stephane Eranian On Fri, Aug 02, 2013 at 06:29:54PM +0200, Frederic Weisbecker wrote: > When we fail to allocate the callchain buffers, we rollback the refcount > we did and return from get_callchain_buffers(). > > However we take the refcount and allocate under the callchain lock > but the rollback is done outside the lock. > > As a result, while we rollback, some concurrent callchain user may > call get_callchain_buffers(), see the non-zero refcount and give up > because the buffers are NULL without itself retrying the allocation. > > The consequences aren't that bad but that behaviour looks weird enough and > it's better to give their chances to the following callchain users where > we failed. > > Reported-by: Jiri Olsa <jolsa@redhat.com> > Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> > Cc: Ingo Molnar <mingo@kernel.org> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Jiri Olsa <jolsa@redhat.com> Acked-by: Jiri Olsa <jolsa@redhat.com> ^ permalink raw reply [flat|nested] 9+ messages in thread
* [tip:perf/core] perf: Roll back callchain buffer refcount under the callchain mutex 2013-08-02 16:29 ` [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex Frederic Weisbecker 2013-08-09 10:28 ` Jiri Olsa @ 2013-08-16 18:47 ` tip-bot for Frederic Weisbecker 1 sibling, 0 replies; 9+ messages in thread From: tip-bot for Frederic Weisbecker @ 2013-08-16 18:47 UTC (permalink / raw) To: linux-tip-commits Cc: linux-kernel, eranian, acme, hpa, mingo, peterz, namhyung, jolsa, fweisbec, tglx Commit-ID: fc3b86d673e41ac66b4ba5b75a90c2fcafb90089 Gitweb: http://git.kernel.org/tip/fc3b86d673e41ac66b4ba5b75a90c2fcafb90089 Author: Frederic Weisbecker <fweisbec@gmail.com> AuthorDate: Fri, 2 Aug 2013 18:29:54 +0200 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Fri, 16 Aug 2013 17:55:50 +0200 perf: Roll back callchain buffer refcount under the callchain mutex When we fail to allocate the callchain buffers, we roll back the refcount we did and return from get_callchain_buffers(). However we take the refcount and allocate under the callchain lock but the rollback is done outside the lock. As a result, while we roll back, some concurrent callchain user may call get_callchain_buffers(), see the non-zero refcount and give up because the buffers are NULL without itself retrying the allocation. The consequences aren't that bad but that behaviour looks weird enough and it's better to give their chances to the following callchain users where we failed. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1375460996-16329-2-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/events/callchain.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 76a8bc5..97b67df 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -116,10 +116,11 @@ int get_callchain_buffers(void) err = alloc_callchain_buffers(); exit: - mutex_unlock(&callchain_mutex); if (err) atomic_dec(&nr_callchain_events); + mutex_unlock(&callchain_mutex); + return err; } ^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH 2/3] perf: Account freq events globally 2013-08-02 16:29 [PATCH 0/3] perf: Fixes on event accounting Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex Frederic Weisbecker @ 2013-08-02 16:29 ` Frederic Weisbecker 2013-08-09 10:33 ` Jiri Olsa 2013-08-16 18:47 ` [tip:perf/core] " tip-bot for Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 3/3] nohz: Include local CPU in full dynticks global kick Frederic Weisbecker 2 siblings, 2 replies; 9+ messages in thread From: Frederic Weisbecker @ 2013-08-02 16:29 UTC (permalink / raw) To: Peter Zijlstra, Jiri Olsa Cc: LKML, Frederic Weisbecker, Ingo Molnar, Namhyung Kim, Arnaldo Carvalho de Melo, Stephane Eranian Freq events may not always be affine to a particular CPU. As such, account_event_cpu() may crash if we account per cpu a freq event that has event->cpu == -1. To solve this, lets account freq events globally. In practice this doesn't change much the picture because perf tools create per-task perf events with one event per CPU by default. Profiling a single CPU is usually a corner case so there is no much point in optimizing things that way. Reported-by: Jiri Olsa <jolsa@redhat.com> Suggested-by: Peter Zijlstra <peterz@infradead.or> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Stephane Eranian <eranian@google.com> --- kernel/events/core.c | 19 ++++++++----------- 1 files changed, 8 insertions(+), 11 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 916cf1f..617f980 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -141,11 +141,11 @@ enum event_type_t { struct static_key_deferred perf_sched_events __read_mostly; static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); static DEFINE_PER_CPU(atomic_t, perf_branch_stack_events); -static DEFINE_PER_CPU(atomic_t, perf_freq_events); static atomic_t nr_mmap_events __read_mostly; static atomic_t nr_comm_events __read_mostly; static atomic_t nr_task_events __read_mostly; +static atomic_t nr_freq_events __read_mostly; static LIST_HEAD(pmus); static DEFINE_MUTEX(pmus_lock); @@ -1871,9 +1871,6 @@ static int __perf_install_in_context(void *info) perf_pmu_enable(cpuctx->ctx.pmu); perf_ctx_unlock(cpuctx, task_ctx); - if (atomic_read(&__get_cpu_var(perf_freq_events))) - tick_nohz_full_kick(); - return 0; } @@ -2811,7 +2808,7 @@ done: #ifdef CONFIG_NO_HZ_FULL bool perf_event_can_stop_tick(void) { - if (atomic_read(&__get_cpu_var(perf_freq_events)) || + if (atomic_read(&nr_freq_events) || __this_cpu_read(perf_throttled_count)) return false; else @@ -3140,9 +3137,6 @@ static void unaccount_event_cpu(struct perf_event *event, int cpu) } if (is_cgroup_event(event)) atomic_dec(&per_cpu(perf_cgroup_events, cpu)); - - if (event->attr.freq) - atomic_dec(&per_cpu(perf_freq_events, cpu)); } static void unaccount_event(struct perf_event *event) @@ -3158,6 +3152,8 @@ static void unaccount_event(struct perf_event *event) atomic_dec(&nr_comm_events); if (event->attr.task) atomic_dec(&nr_task_events); + if (event->attr.freq) + atomic_dec(&nr_freq_events); if (is_cgroup_event(event)) static_key_slow_dec_deferred(&perf_sched_events); if (has_branch_stack(event)) @@ -6479,9 +6475,6 @@ static void account_event_cpu(struct perf_event *event, int cpu) } if (is_cgroup_event(event)) atomic_inc(&per_cpu(perf_cgroup_events, cpu)); - - if (event->attr.freq) - atomic_inc(&per_cpu(perf_freq_events, cpu)); } static void account_event(struct perf_event *event) @@ -6497,6 +6490,10 @@ static void account_event(struct perf_event *event) atomic_inc(&nr_comm_events); if (event->attr.task) atomic_inc(&nr_task_events); + if (event->attr.freq) { + if (atomic_inc_return(&nr_freq_events) == 1) + tick_nohz_full_kick_all(); + } if (has_branch_stack(event)) static_key_slow_inc(&perf_sched_events.key); if (is_cgroup_event(event)) -- 1.7.5.4 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH 2/3] perf: Account freq events globally 2013-08-02 16:29 ` [PATCH 2/3] perf: Account freq events globally Frederic Weisbecker @ 2013-08-09 10:33 ` Jiri Olsa 2013-08-16 18:47 ` [tip:perf/core] " tip-bot for Frederic Weisbecker 1 sibling, 0 replies; 9+ messages in thread From: Jiri Olsa @ 2013-08-09 10:33 UTC (permalink / raw) To: Frederic Weisbecker Cc: Peter Zijlstra, LKML, Ingo Molnar, Namhyung Kim, Arnaldo Carvalho de Melo, Stephane Eranian On Fri, Aug 02, 2013 at 06:29:55PM +0200, Frederic Weisbecker wrote: > Freq events may not always be affine to a particular CPU. As such, > account_event_cpu() may crash if we account per cpu a freq event > that has event->cpu == -1. > > To solve this, lets account freq events globally. In practice > this doesn't change much the picture because perf tools create > per-task perf events with one event per CPU by default. Profiling a > single CPU is usually a corner case so there is no much point in > optimizing things that way. > > Reported-by: Jiri Olsa <jolsa@redhat.com> > Suggested-by: Peter Zijlstra <peterz@infradead.or> > Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> > Cc: Ingo Molnar <mingo@kernel.org> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Jiri Olsa <jolsa@redhat.com> > Cc: Namhyung Kim <namhyung@kernel.org> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Cc: Stephane Eranian <eranian@google.com> no more OOPSes ;-) Tested-by: Jiri Olsa <jolsa@redhat.com ^ permalink raw reply [flat|nested] 9+ messages in thread
* [tip:perf/core] perf: Account freq events globally 2013-08-02 16:29 ` [PATCH 2/3] perf: Account freq events globally Frederic Weisbecker 2013-08-09 10:33 ` Jiri Olsa @ 2013-08-16 18:47 ` tip-bot for Frederic Weisbecker 1 sibling, 0 replies; 9+ messages in thread From: tip-bot for Frederic Weisbecker @ 2013-08-16 18:47 UTC (permalink / raw) To: linux-tip-commits Cc: linux-kernel, eranian, acme, hpa, mingo, peterz, namhyung, jolsa, fweisbec, tglx Commit-ID: 948b26b6ddd08a57cb95ebb0dc96fde2edd5c383 Gitweb: http://git.kernel.org/tip/948b26b6ddd08a57cb95ebb0dc96fde2edd5c383 Author: Frederic Weisbecker <fweisbec@gmail.com> AuthorDate: Fri, 2 Aug 2013 18:29:55 +0200 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Fri, 16 Aug 2013 17:55:51 +0200 perf: Account freq events globally Freq events may not always be affine to a particular CPU. As such, account_event_cpu() may crash if we account per cpu a freq event that has event->cpu == -1. To solve this, lets account freq events globally. In practice this doesn't change much the picture because perf tools create per-task perf events with one event per CPU by default. Profiling a single CPU is usually a corner case so there is no much point in optimizing things that way. Reported-by: Jiri Olsa <jolsa@redhat.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1375460996-16329-3-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/events/core.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index e82e700..2e675e8 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -141,11 +141,11 @@ enum event_type_t { struct static_key_deferred perf_sched_events __read_mostly; static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); static DEFINE_PER_CPU(atomic_t, perf_branch_stack_events); -static DEFINE_PER_CPU(atomic_t, perf_freq_events); static atomic_t nr_mmap_events __read_mostly; static atomic_t nr_comm_events __read_mostly; static atomic_t nr_task_events __read_mostly; +static atomic_t nr_freq_events __read_mostly; static LIST_HEAD(pmus); static DEFINE_MUTEX(pmus_lock); @@ -1871,9 +1871,6 @@ static int __perf_install_in_context(void *info) perf_pmu_enable(cpuctx->ctx.pmu); perf_ctx_unlock(cpuctx, task_ctx); - if (atomic_read(&__get_cpu_var(perf_freq_events))) - tick_nohz_full_kick(); - return 0; } @@ -2811,7 +2808,7 @@ done: #ifdef CONFIG_NO_HZ_FULL bool perf_event_can_stop_tick(void) { - if (atomic_read(&__get_cpu_var(perf_freq_events)) || + if (atomic_read(&nr_freq_events) || __this_cpu_read(perf_throttled_count)) return false; else @@ -3140,9 +3137,6 @@ static void unaccount_event_cpu(struct perf_event *event, int cpu) } if (is_cgroup_event(event)) atomic_dec(&per_cpu(perf_cgroup_events, cpu)); - - if (event->attr.freq) - atomic_dec(&per_cpu(perf_freq_events, cpu)); } static void unaccount_event(struct perf_event *event) @@ -3158,6 +3152,8 @@ static void unaccount_event(struct perf_event *event) atomic_dec(&nr_comm_events); if (event->attr.task) atomic_dec(&nr_task_events); + if (event->attr.freq) + atomic_dec(&nr_freq_events); if (is_cgroup_event(event)) static_key_slow_dec_deferred(&perf_sched_events); if (has_branch_stack(event)) @@ -6489,9 +6485,6 @@ static void account_event_cpu(struct perf_event *event, int cpu) } if (is_cgroup_event(event)) atomic_inc(&per_cpu(perf_cgroup_events, cpu)); - - if (event->attr.freq) - atomic_inc(&per_cpu(perf_freq_events, cpu)); } static void account_event(struct perf_event *event) @@ -6507,6 +6500,10 @@ static void account_event(struct perf_event *event) atomic_inc(&nr_comm_events); if (event->attr.task) atomic_inc(&nr_task_events); + if (event->attr.freq) { + if (atomic_inc_return(&nr_freq_events) == 1) + tick_nohz_full_kick_all(); + } if (has_branch_stack(event)) static_key_slow_inc(&perf_sched_events.key); if (is_cgroup_event(event)) ^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH 3/3] nohz: Include local CPU in full dynticks global kick 2013-08-02 16:29 [PATCH 0/3] perf: Fixes on event accounting Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 2/3] perf: Account freq events globally Frederic Weisbecker @ 2013-08-02 16:29 ` Frederic Weisbecker 2013-08-16 18:46 ` [tip:timers/nohz] " tip-bot for Frederic Weisbecker 2 siblings, 1 reply; 9+ messages in thread From: Frederic Weisbecker @ 2013-08-02 16:29 UTC (permalink / raw) To: Peter Zijlstra, Jiri Olsa Cc: LKML, Frederic Weisbecker, Steven Rostedt, Paul E. McKenney, Ingo Molnar, Thomas Gleixner, Borislav Petkov, Li Zhong, Mike Galbraith, Kevin Hilman tick_nohz_full_kick_all() is useful to notify all full dynticks CPUs that there is a system state change to checkout before re-evaluating the need for the tick. Unfortunately this is implemented using smp_call_function_many() that ignores the local CPU. This CPU also needs to re-evaluate the tick. on_each_cpu_mask() is not useful either because we don't want to re-evaluate the tick state in place but asynchronously from an IPI to avoid messing up with any random locking scenario. Sol lets call tick_nohz_full_kick() from tick_nohz_full_kick_all() so that the usual irq work takes care of it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org> --- kernel/time/tick-sched.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index e80183f..30849d4 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -244,6 +244,7 @@ void tick_nohz_full_kick_all(void) preempt_disable(); smp_call_function_many(nohz_full_mask, nohz_full_kick_ipi, NULL, false); + tick_nohz_full_kick(); preempt_enable(); } -- 1.7.5.4 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* [tip:timers/nohz] nohz: Include local CPU in full dynticks global kick 2013-08-02 16:29 ` [PATCH 3/3] nohz: Include local CPU in full dynticks global kick Frederic Weisbecker @ 2013-08-16 18:46 ` tip-bot for Frederic Weisbecker 0 siblings, 0 replies; 9+ messages in thread From: tip-bot for Frederic Weisbecker @ 2013-08-16 18:46 UTC (permalink / raw) To: linux-tip-commits Cc: linux-kernel, hpa, mingo, peterz, efault, bp, paulmck, zhong, fweisbec, rostedt, khilman, tglx Commit-ID: c2e7fcf53c3cb02b4ada1c66a9bc8a4d97d58aba Gitweb: http://git.kernel.org/tip/c2e7fcf53c3cb02b4ada1c66a9bc8a4d97d58aba Author: Frederic Weisbecker <fweisbec@gmail.com> AuthorDate: Fri, 2 Aug 2013 18:29:56 +0200 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Fri, 16 Aug 2013 17:55:33 +0200 nohz: Include local CPU in full dynticks global kick tick_nohz_full_kick_all() is useful to notify all full dynticks CPUs that there is a system state change to checkout before re-evaluating the need for the tick. Unfortunately this is implemented using smp_call_function_many() that ignores the local CPU. This CPU also needs to re-evaluate the tick. on_each_cpu_mask() is not useful either because we don't want to re-evaluate the tick state in place but asynchronously from an IPI to avoid messing up with any random locking scenario. So lets call tick_nohz_full_kick() from tick_nohz_full_kick_all() so that the usual irq work takes care of it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1375460996-16329-4-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/time/tick-sched.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index adea6fc3..3612fc7 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -246,6 +246,7 @@ void tick_nohz_full_kick_all(void) preempt_disable(); smp_call_function_many(tick_nohz_full_mask, nohz_full_kick_ipi, NULL, false); + tick_nohz_full_kick(); preempt_enable(); } ^ permalink raw reply related [flat|nested] 9+ messages in thread
end of thread, other threads:[~2013-08-16 18:48 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2013-08-02 16:29 [PATCH 0/3] perf: Fixes on event accounting Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 1/3] perf: Rollback callchain buffer refcount under the callchain mutex Frederic Weisbecker 2013-08-09 10:28 ` Jiri Olsa 2013-08-16 18:47 ` [tip:perf/core] perf: Roll back " tip-bot for Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 2/3] perf: Account freq events globally Frederic Weisbecker 2013-08-09 10:33 ` Jiri Olsa 2013-08-16 18:47 ` [tip:perf/core] " tip-bot for Frederic Weisbecker 2013-08-02 16:29 ` [PATCH 3/3] nohz: Include local CPU in full dynticks global kick Frederic Weisbecker 2013-08-16 18:46 ` [tip:timers/nohz] " tip-bot for Frederic Weisbecker
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