Messages in this thread | | | Date | Sun, 26 May 2013 17:38:53 -0400 | From | KOSAKI Motohiro <> | Subject | Re: [PATCH 1/7] posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting |
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(5/7/13 11:24 AM), Frederic Weisbecker wrote: > 2013/5/7 KOSAKI Motohiro <kosaki.motohiro@gmail.com>: >>>> + /* >>>> + * After turning over se.sum_exec_runtime to sig->sum_sched_runtime >>>> + * in __exit_signal(), we must not account exec_runtime for consistency. >>>> + */ >>>> + if (unlikely(!tsk->sighand)) >>>> + return; >>> >>> Ok, if we want the clock and timer to be consistent, do we also want the same check in >>> account_group_user_time() and account_group_system_time()? The task can still account >>> a tick after autoreaping itself between release_task() and the final schedule(). >> >> You are right. >> >> That said, current the man pages don't describe this linux specific >> extensions. So, nobody >> (glibc, ltp, and me) tested them. Please give me a couple of days. >> I'll test and fix this features >> too. >> >> timer_create(2): http://man7.org/linux/man-pages/man2/timer_create.2.html > > Ah, indeed timer_create() seem to only create CPUCLOCK_SCHED timers. So that > issue with timer_gettime becoming asynchonous with clock_gettime can't happen > with PROF and VIRT clocks > > I see itimers can use those clocks. But there don't seem to be a > similar issue with > getitimer/setitimer as they don't have matching clock reads.
OK. I've found PROF and VIRT clock of posix timer have a bug and I could narrow down and fixed it. Please see my next iteration.
Thanks.
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