Re: [PATCH] tools/perf: add breakpoint benchmarks

[Dmitry Vyukov <dvyukov@google.com>]

On Wed, 11 May 2022 at 20:17, Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
> > >
> > > Acked-by: Ian Rogers <irogers@google.com>
> >
> > Thanks, applied.
>
> But I'll add some error checks, etc, running as !root, in a toolbox in
> Fedora Silverblue produces:

Thanks!

> ⬢[acme@toolbox perf]$ perf bench breakpoint all
> # Running breakpoint/thread benchmark...
> # Created/joined 10 threads with 1 breakpoints and 1 parallelism
>      Total time: 0.000 [sec]
>
>       54.600000 usecs/op
>       54.600000 usecs/op/cpu
>
> # Running breakpoint/enable benchmark...
> # Enabled/disabled breakpoint 10 time with 0 passive and 0 active threads
>      Total time: 0.000 [sec]
>
>        1.100000 usecs/op
>
> ⬢[acme@toolbox perf]$
>
> ⬢[acme@toolbox perf]$ perf bench --repeat=20000 breakpoint enable --passive=224 --active=0
> # Running 'breakpoint/enable' benchmark:
> # Enabled/disabled breakpoint 20000 time with 224 passive and 0 active threads
>      Total time: 8.933 [sec]
>
>      446.674950 usecs/op
> ⬢[acme@toolbox perf]$
>
> $ grep -m1 "model name" /proc/cpuinfo
> model name      : AMD Ryzen 9 5950X 16-Core Processor
>
> Diff:
>
> diff --git a/tools/perf/bench/breakpoint.c b/tools/perf/bench/breakpoint.c
> index 56936fea246d73c2..d2c074bba06a3d1f 100644
> --- a/tools/perf/bench/breakpoint.c
> +++ b/tools/perf/bench/breakpoint.c
> @@ -83,6 +83,9 @@ static void *breakpoint_thread(void *arg)
>         pthread_t *threads;
>
>         threads = calloc(thread_params.nthreads, sizeof(threads[0]));
> +       if (!threads)
> +               exit((perror("calloc"), EXIT_FAILURE));
> +
>         while (__atomic_fetch_sub(repeat, 1, __ATOMIC_RELAXED) > 0) {
>                 done = 0;
>                 for (i = 0; i < thread_params.nthreads; i++) {
> @@ -114,6 +117,9 @@ int bench_breakpoint_thread(int argc, const char **argv)
>         }
>         breakpoints = calloc(thread_params.nbreakpoints, sizeof(breakpoints[0]));
>         parallel = calloc(thread_params.nparallel, sizeof(parallel[0]));
> +       if (!breakpoints || !parallel)
> +               exit((perror("calloc"), EXIT_FAILURE));
> +
>         for (i = 0; i < thread_params.nbreakpoints; i++) {
>                 breakpoints[i].fd = breakpoint_setup(&breakpoints[i].watched);
>                 if (breakpoints[i].fd == -1)
> @@ -194,6 +200,9 @@ int bench_breakpoint_enable(int argc, const char **argv)
>                 exit((perror("perf_event_open"), EXIT_FAILURE));
>         nthreads = enable_params.npassive + enable_params.nactive;
>         threads = calloc(nthreads, sizeof(threads[0]));
> +       if (!threads)
> +               exit((perror("calloc"), EXIT_FAILURE));
> +
>         for (i = 0; i < nthreads; i++) {
>                 if (pthread_create(&threads[i], NULL,
>                         i < enable_params.npassive ? passive_thread : active_thread, &done))