Messages in this thread | | | Date | Fri, 23 Mar 2018 10:24:30 +0100 | From | Jiri Olsa <> | Subject | Re: [PATCH v2 0/3] perf/core: expose thread context switch out event type to user space |
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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: > > event_header->misc &= > PERF_RECORD_MISC_SWITCH_OUT|PERF_RECORD_MISC_SWITCH_OUT_YIELD > > Perf tool report and script commands output has been extended to decode > new yield bit and the updated output looks like in the examples below. > > The documentation has been updated to mention yield switch out events > and its decoding symbols in perf script output. > > The changes have been manually tested on Fedora 27 with the patched kernel: > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf/core > > perf report -D -i system-wide.perf | grep _SWITCH: > > 1 113807080924003 0x26db26 [0x28]: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 20495/20495 > 1 113807080925644 0x26db4e [0x28]: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 31479/31479 > 1 113807080937266 0x26db76 [0x28]: PERF_RECORD_SWITCH_CPU_WIDE OUT yield next pid/tid: 16/16 > 1 113807080938445 0x26db9e [0x28]: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 20495/20495 > 1 113807080945455 0x26dbc6 [0x28]: PERF_RECORD_SWITCH_CPU_WIDE OUT yield next pid/tid: 20495/20495 > > perf script --show-switch-events -F +misc -I -i system-wide.perf: > > rcu_sched 8 [003] 113800.748548: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 > perf 31479 [000] S 113800.748548: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 59/59 > kworker/0:1 59 [000] 113800.748549: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 31479/31479 > rcu_sched 8 [003] Sy 113800.748551: PERF_RECORD_SWITCH_CPU_WIDE OUT yield next pid/tid: 0/0 > swapper 0 [003] 113800.748551: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 8/8
Acked-by: Jiri Olsa <jolsa@kernel.org>
thanks, jirka
> > --- > Alexey Budankov (3): > perf/core: store context switch out type into Perf trace > perf report: extend raw dump (-D) out with switch out event type > perf script: extend misc field decoding with switch out event type > > include/uapi/linux/perf_event.h | 5 +++++ > kernel/events/core.c | 4 +++- > tools/include/uapi/linux/perf_event.h | 5 +++++ > tools/perf/Documentation/perf-script.txt | 17 +++++++++-------- > tools/perf/builtin-script.c | 5 ++++- > tools/perf/util/event.c | 4 +++- > 6 files changed, 29 insertions(+), 11 deletions(-)
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