Hi Arnaldo, Could you please take a look at this?
Thanks, Namhyung On Wed, Nov 16, 2016 at 03:06:26PM +0900, Namhyung Kim wrote: > Hello, > > This patchset is a rebased version of David's sched timehist work [1]. > I plan to improve perf sched command more and think that having > timehist command before the work looks good. It seems David is busy > these days, so I'm retrying it by myself. > > * changes in v2) > - change name 'b/n time' to 'wait time' (Ingo) > - show arrow between functions in the callchain (Ingo) > - fix a bug in calculating initial run time > > This implements only basic feature and a few options. I just split > the patch to make it easier to review and did some cosmetic changes. > More patches will come later. > > The below is from the David's original description (w/ slight change): > > ------------------------8<------------------------- > 'perf sched timehist' provides an analysis of scheduling events. > > Example usage: > perf sched record -- sleep 1 > perf sched timehist > > By default it shows the individual schedule events, including the time between > sched-in events for the task, the task scheduling delay (time between wakeup > and actually running) and run time for the task: > > time cpu task name[tid/pid] wait time sch delay run time > ------------- ---- -------------------- --------- --------- --------- > 79371.874569 [11] gcc[31949] 0.014 0.000 1.148 > 79371.874591 [10] gcc[31951] 0.000 0.000 0.024 > 79371.874603 [10] migration/10[59] 3.350 0.004 0.011 > 79371.874604 [11] <idle> 1.148 0.000 0.035 > 79371.874723 [05] <idle> 0.016 0.000 1.383 > 79371.874746 [05] gcc[31949] 0.153 0.078 0.022 > ... > > Times are in msec.usec. > > If callchains were recorded they are appended to the line with a default > stack depth of 5: > > 79371.874569 [11] gcc[31949] 0.014 0.000 1.148 > wait_for_completion_killable <- do_fork <- sys_vfork <- stub_vfork <- __vfork > 79371.874591 [10] gcc[31951] 0.000 0.000 0.024 > __cond_resched <- _cond_resched <- wait_for_completion <- stop_one_cpu <- > sched_exec > 79371.874603 [10] migration/10[59] 3.350 0.004 0.011 > smpboot_thread_fn <- kthread <- ret_from_fork > 79371.874604 [11] <idle> 1.148 0.000 0.035 > cpu_startup_entry <- start_secondary > 79371.874723 [05] <idle> 0.016 0.000 1.383 > cpu_startup_entry <- start_secondary > 79371.874746 [05] gcc[31949] 0.153 0.078 0.022 > do_wait sys_wait4 <- system_call_fastpath <- __GI___waitpid > > --no-call-graph can be used to not show the callchains. --max-stack is used > to control the number of frames shown (default of 5). -x/--excl options can > be used to collapse redundant callchains to get more relevant data on screen. > > Similar to perf-trace -s and -S can be used to dump a statistical summary > without or with events (respectively). Statistics include min run time, > average run time and max run time. Stats are also shown for run time by > cpu. > > The cpu-visual option provides a visual aid for sched switches by cpu: > ... > 79371.874569 [11] s gcc[31949] 0.014 > 0.000 1.148 > 79371.874591 [10] s gcc[31951] 0.000 > 0.000 0.024 > 79371.874603 [10] s migration/10[59] 3.350 > 0.004 0.011 > 79371.874604 [11] i <idle> 1.148 > 0.000 0.035 > 79371.874723 [05] i <idle> 0.016 > 0.000 1.383 > 79371.874746 [05] s gcc[31949] 0.153 > 0.078 0.022 > ... > > ------------------------8<------------------------- > > This code is available at 'perf/timehist-v2' branch in my tree > > git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git > > Any feedback is welcomed. > > Thanks, > Namhyung > > > [1] https://lkml.org/lkml/2013/12/1/129 > > David Ahern (6): > perf sched timehist: Introduce timehist command > perf sched timehist: Add summary options > perf sched timehist: Add -w/--wakeups option > perf sched timehist: Add call graph options > perf sched timehist: Add -V/--cpu-visual option > perf sched: Add documentation for timehist options > > Namhyung Kim (2): > perf symbol: Print symbol offsets conditionally > perf tools: Support printing callchains with arrows > > tools/perf/Documentation/perf-sched.txt | 46 +- > tools/perf/builtin-sched.c | 914 > +++++++++++++++++++++++++++++++- > tools/perf/util/evsel.h | 1 + > tools/perf/util/evsel_fprintf.c | 12 +- > tools/perf/util/symbol.h | 3 +- > tools/perf/util/symbol_fprintf.c | 11 +- > 6 files changed, 972 insertions(+), 15 deletions(-) > > -- > 2.10.1 >
