Hi Masami, On Wed, 2018-04-04 at 21:33 +0900, Masami Hiramatsu wrote: > Hi Tom, > > On Mon, 02 Apr 2018 12:09:33 -0500 > Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx> wrote: > > > after: > > > > # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events > > # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger > > # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger > > # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger > > # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger > > # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger > > I ensured this sequence has no problem. > After above sequence, the trigger file shows > > ====== > # cat events/sched/sched_switch/trigger > hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0:sort=hitcount:size=2048:clock=global if next_comm=="cyclictest" [active] > hist:keys=next_pid:vals=hitcount:sort=hitcount:size=2048:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest" [active] > hist:keys=next_pid:vals=hitcount:sort=hitcount:size=2048:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest" [active] > hist:keys=next_pid:vals=hitcount:sort=hitcount:size=2048 if next_comm=="cyclictest" [active] > ====== > > So I clear the last one > > ====== > # echo '!hist:keys=next_pid if next_comm=="cyclictest"' >> events/sched/sched_switch/trigger > # > ====== > > OK, it should be removed. I can not see it anymore on the trigger file. > > ====== > # cat events/sched/sched_switch/trigger > hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0:sort=hitcount:size=2048:clock=global if next_comm=="cyclictest" [active] > hist:keys=next_pid:vals=hitcount:sort=hitcount:size=2048:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest" [active] > hist:keys=next_pid:vals=hitcount:sort=hitcount:size=2048:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest" [active] > ====== > > But when I missed to remove it again, it is accepted (is not an error?) > > ====== > # echo '!hist:keys=next_pid if next_comm=="cyclictest"' >> events/sched/sched_switch/trigger > # > ====== This is consistent with existing behavior, not only for the hist triggers but ftrace in general I think e.g. # echo 'traceoff:1 if nr_rq > 1' >> /sys/kernel/debug/tracing/events/block/block_unplug/trigger # echo '!traceoff:1 if nr_rq > 1' >> /sys/kernel/debug/tracing/events/block/block_unplug/trigger # echo '!traceoff:1 if nr_rq > 1' >> /sys/kernel/debug/tracing/events/block/block_unplug/trigger # echo 'try_to_wake_up:enable_event:sched:sched_switch:2' >> set_ftrace_filter # echo '!try_to_wake_up:enable_event:sched:sched_switch:2' >> set_ftrace_filter # echo '!try_to_wake_up:enable_event:sched:sched_switch:2' >> set_ftrace_filter Neither produces an error trying to remove an already-removed trigger. Or are you thinking about something else? > > Hmm... anyway, let's clear others too. > > ====== > # echo '!hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> events/sched/sched_switch/trigger > # echo '!hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> events/sched/sched_switch/trigger > # cat events/sched/sched_switch/trigger > # Available triggers: > # traceon traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist > ====== > > OK, it is cleared now. > > Now I test it again. > > ====== > # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> events/sched/sched_wakeup/trigger > sh: write error: Invalid argument > ====== > > Oops, what's the error? > > ====== > # cat events/sched/sched_switch/hist > > ERROR: Variable already defined: ts0 > Last command: keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest" > ====== > Hmm, but ts0 is defined on sched_wakeup - you removed the triggers on sched_switch, but I didn't see where you removed the sched_wakeup trigger defining ts0... > Hmm, how can I undef ts0 and test it again? You should be able to remove the sched_wakeup trigger defining ts0 and after doing that test again. At least I was able to: # echo '!hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> events/sched/sched_wakeup/trigger # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> events/sched/sched_wakeup/trigger Thanks, Tom > If I can not clean it, the testcase must fail on the 2nd time. > > Thank you, > -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
