Re: [PATCH v3] perf/core: Avoid context switch overheads

2017-08-09 Thread Peter Zijlstra
On Wed, Aug 09, 2017 at 08:29:21AM +0800, 石祤 wrote: > 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, an

[PATCH v3] perf/core: Avoid context switch overheads

2017-08-08 Thread linxiulei
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 v3] 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. __