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

2017-08-07 Thread Peter Zijlstra
On Mon, Aug 07, 2017 at 02:15:51PM +0200, Peter Zijlstra wrote: > On Fri, Aug 04, 2017 at 04:50:54PM +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

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

2017-08-07 Thread Peter Zijlstra
On Mon, Aug 07, 2017 at 02:15:51PM +0200, Peter Zijlstra wrote: > On Fri, Aug 04, 2017 at 04:50:54PM +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

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

2017-08-07 Thread Peter Zijlstra
On Fri, Aug 04, 2017 at 04:50:54PM +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

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

2017-08-07 Thread Peter Zijlstra
On Fri, Aug 04, 2017 at 04:50:54PM +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,

[PATCH] perf/core: Avoid context switch overheads

2017-08-04 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

[PATCH] perf/core: Avoid context switch overheads

2017-08-04 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.