Re: [PATCH 1/3] perf record: Fix per-thread option.

From: Arnaldo Carvalho de Melo
Date: Wed Apr 13 2022 - 21:31:24 EST


Em Wed, Apr 13, 2022 at 04:42:07AM +0300, Alexey Bayduraev escreveu:
> On 12.04.2022 09:21, Ian Rogers wrote:
>
> > From: Alexey Bayduraev <alexey.bayduraev@xxxxxxxxx>
>
> Thanks,
>
> The tag
> Signed-off-by: Alexey Bayduraev <alexey.bayduraev@xxxxxxxxx>
> can be added to this patch.

Thanks, will add that to the cset,

Best regards,

- Arnaldo

> Regards,
> Alexey
>
> >
> > Per-thread mode doesn't have specific CPUs for events, add checks for
> > this case.
> >
> > Minor fix to a pr_debug by Ian Rogers <irogers@xxxxxxxxxx> to avoid an
> > out of bound array access.
> >
> > Reported-by: Ian Rogers <irogers@xxxxxxxxxx>
> > Fixes: 7954f71689f9 ("perf record: Introduce thread affinity and mmap masks")
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > ---
> > tools/perf/builtin-record.c | 22 +++++++++++++++++-----
> > 1 file changed, 17 insertions(+), 5 deletions(-)
> >
> > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> > index ba74fab02e62..069825c48d40 100644
> > --- a/tools/perf/builtin-record.c
> > +++ b/tools/perf/builtin-record.c
> > @@ -989,8 +989,11 @@ static int record__thread_data_init_maps(struct record_thread *thread_data, stru
> > struct mmap *overwrite_mmap = evlist->overwrite_mmap;
> > struct perf_cpu_map *cpus = evlist->core.user_requested_cpus;
> >
> > - thread_data->nr_mmaps = bitmap_weight(thread_data->mask->maps.bits,
> > - thread_data->mask->maps.nbits);
> > + if (cpu_map__is_dummy(cpus))
> > + thread_data->nr_mmaps = nr_mmaps;
> > + else
> > + thread_data->nr_mmaps = bitmap_weight(thread_data->mask->maps.bits,
> > + thread_data->mask->maps.nbits);
> > if (mmap) {
> > thread_data->maps = zalloc(thread_data->nr_mmaps * sizeof(struct mmap *));
> > if (!thread_data->maps)
> > @@ -1007,16 +1010,17 @@ static int record__thread_data_init_maps(struct record_thread *thread_data, stru
> > thread_data->nr_mmaps, thread_data->maps, thread_data->overwrite_maps);
> >
> > for (m = 0, tm = 0; m < nr_mmaps && tm < thread_data->nr_mmaps; m++) {
> > - if (test_bit(cpus->map[m].cpu, thread_data->mask->maps.bits)) {
> > + if (cpu_map__is_dummy(cpus) ||
> > + test_bit(cpus->map[m].cpu, thread_data->mask->maps.bits)) {
> > if (thread_data->maps) {
> > thread_data->maps[tm] = &mmap[m];
> > pr_debug2("thread_data[%p]: cpu%d: maps[%d] -> mmap[%d]\n",
> > - thread_data, cpus->map[m].cpu, tm, m);
> > + thread_data, perf_cpu_map__cpu(cpus, m).cpu, tm, m);
> > }
> > if (thread_data->overwrite_maps) {
> > thread_data->overwrite_maps[tm] = &overwrite_mmap[m];
> > pr_debug2("thread_data[%p]: cpu%d: ow_maps[%d] -> ow_mmap[%d]\n",
> > - thread_data, cpus->map[m].cpu, tm, m);
> > + thread_data, perf_cpu_map__cpu(cpus, m).cpu, tm, m);
> > }
> > tm++;
> > }
> > @@ -3329,6 +3333,9 @@ static void record__mmap_cpu_mask_init(struct mmap_cpu_mask *mask, struct perf_c
> > {
> > int c;
> >
> > + if (cpu_map__is_dummy(cpus))
> > + return;
> > +
> > for (c = 0; c < cpus->nr; c++)
> > set_bit(cpus->map[c].cpu, mask->bits);
> > }
> > @@ -3680,6 +3687,11 @@ static int record__init_thread_masks(struct record *rec)
> > if (!record__threads_enabled(rec))
> > return record__init_thread_default_masks(rec, cpus);
> >
> > + if (cpu_map__is_dummy(cpus)) {
> > + pr_err("--per-thread option is mutually exclusive to parallel streaming mode.\n");
> > + return -EINVAL;
> > + }
> > +
> > switch (rec->opts.threads_spec) {
> > case THREAD_SPEC__CPU:
> > ret = record__init_thread_cpu_masks(rec, cpus);
> >

--

- Arnaldo