Messages in this thread | | | Subject | Re: [PATCH v2 0/3] perf/core: expose thread context switch out event type to user space | From | Alexey Budankov <> | Date | Fri, 23 Mar 2018 23:38:03 +0300 |
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On 23.03.2018 21:05, Peter Zijlstra wrote: > On Thu, Mar 22, 2018 at 07:08:25PM +0300, Alexey Budankov wrote: >> >> Implementation of exposing context-switch-out type event as a part >> of PERF_RECORD_SWITCH[_CPU_WIDE] record. >> >> Introduced types of events assumed to be: >> a) preempt: when task->state == TASK_RUNNING >> b) yield: !preempt, encoding is done using new bit >> PERF_RECORD_MISC_SWITCH_OUT_YIELD like this: > > A !preempt context switch isn't nessecarily a yield; please don't use > that name, it means something quite specific and this isn't it. > > Specifically, on Linux yield() doesn't actually change task->state, so > when task->state is set !0 it _cannot_ have been yield. > > I would invert the thing and call the preempt one SWITCH_OUT_PREEMPT. >
Make sense. This way it names the thing exactly what it is. Let me take care of that.
Thanks, Alexey
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