Re: [PATCH v2] perf/core: Avoid context switch overheads

2017-08-08 Thread 林守磊
2017-08-08 18:37 GMT+08:00 Peter Zijlstra : > On Tue, Aug 08, 2017 at 06:00:45PM +0800, 石祤 wrote: > >> diff --git a/kernel/events/core.c b/kernel/events/core.c >> index 426c2ff..3d86695 100644 >> --- a/kernel/events/core.c >> +++ b/kernel/events/core.c >> @@ -3180,6 +3180,13 @@ static void perf_eve

Re: [PATCH v2] perf/core: Avoid context switch overheads

2017-08-08 Thread Peter Zijlstra
On Tue, Aug 08, 2017 at 06:00:45PM +0800, 石祤 wrote: > diff --git a/kernel/events/core.c b/kernel/events/core.c > index 426c2ff..3d86695 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -3180,6 +3180,13 @@ static void perf_event_context_sched_in(struct > perf_event_context *ct

[PATCH v2] perf/core: Avoid context switch overheads

2017-08-08 Thread 石祤
From: "leilei.lin" A performance issue caused by less strickly check in task sched when these tasks were once attached by per-task perf_event. A task will alloc task->perf_event_ctxp[ctxn] when it was called by perf_event_open, and task->perf_event_ctxp[ctxn] would not ever be freed to NULL. __

[PATCH v2] perf/core: Avoid context switch overheads

2017-08-07 Thread 石祤
From: "leilei.lin" A performance issue caused by less strickly check in task sched when these tasks were once attached by per-task perf_event. A task will alloc task->perf_event_ctxp[ctxn] when it was called by perf_event_open, and task->perf_event_ctxp[ctxn] would not ever be freed to NULL. __