Messages in this thread | | | From | Ian Rogers <> | Date | Wed, 22 Apr 2020 10:37:38 -0700 | Subject | Re: [PATCH v2] perf record: add dummy event during system wide synthesis |
| |
On Wed, Apr 22, 2020 at 1:46 AM Jiri Olsa <jolsa@redhat.com> wrote: > > On Mon, Apr 20, 2020 at 11:11:03PM -0700, Ian Rogers wrote: > > During the processing of /proc during event synthesis new processes may > > start. Add a dummy event if /proc is to be processed, to capture mmaps > > for starting processes. This reuses the existing logic for > > initial-delay. > > > > v2 fixes the dummy event configuration and a branch stack issue. > > heya, > it's breaking attr tests for me: > > [jolsa@krava perf]$ sudo ./perf test -v 17 > 17: Setup struct perf_event_attr : > --- start --- > test child forked, pid 1046560 > running './tests/attr/test-record-graph-default' > running './tests/attr/test-record-raw' > running './tests/attr/test-record-branch-filter-any' > running './tests/attr/test-record-freq' > running './tests/attr/test-record-branch-any' > running './tests/attr/test-stat-group1' > running './tests/attr/test-record-no-samples' > running './tests/attr/test-record-graph-dwarf' > running './tests/attr/test-stat-C0' > running './tests/attr/test-stat-basic' > running './tests/attr/test-record-group' > running './tests/attr/test-record-branch-filter-k' > running './tests/attr/test-stat-group' > running './tests/attr/test-record-C0' > expected config=0, got 9 > expected sample_type=391, got 455 > expected disabled=1, got 0 > FAILED './tests/attr/test-record-C0' - match failure > test child finished with -1 > ---- end ---- > Setup struct perf_event_attr: FAILED! > > jirka
Thanks, fixed in v3: https://lore.kernel.org/lkml/20200422173615.59436-1-irogers@google.com/
Ian
> > > > Suggested-by: Stephane Eranian <eranian@google.com> > > Signed-off-by: Ian Rogers <irogers@google.com> > > --- > > tools/perf/builtin-record.c | 19 ++++++++++++++----- > > tools/perf/util/evsel.c | 5 ++++- > > 2 files changed, 18 insertions(+), 6 deletions(-) > > > > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > > index 1ab349abe904..8d1e93351298 100644 > > --- a/tools/perf/builtin-record.c > > +++ b/tools/perf/builtin-record.c > > @@ -805,19 +805,28 @@ static int record__open(struct record *rec) > > int rc = 0; > > > > /* > > - * For initial_delay we need to add a dummy event so that we can track > > - * PERF_RECORD_MMAP while we wait for the initial delay to enable the > > - * real events, the ones asked by the user. > > + * For initial_delay or system wide, we need to add a dummy event so > > + * that we can track PERF_RECORD_MMAP to cover the delay of waiting or > > + * event synthesis. > > */ > > - if (opts->initial_delay) { > > + if (opts->initial_delay || target__has_cpu(&opts->target)) { > > if (perf_evlist__add_dummy(evlist)) > > return -ENOMEM; > > > > + /* Disable tracking of mmaps on lead event. */ > > pos = evlist__first(evlist); > > pos->tracking = 0; > > + /* Set up dummy event. */ > > pos = evlist__last(evlist); > > pos->tracking = 1; > > - pos->core.attr.enable_on_exec = 1; > > + /* > > + * Enable the dummy event when the process is forked for > > + * initial_delay, immediately for system wide. > > + */ > > + if (opts->initial_delay) > > + pos->core.attr.enable_on_exec = 1; > > + else > > + pos->immediate = 1; > > } > > > > perf_evlist__config(evlist, opts, &callchain_param); > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > > index 6a571d322bb2..ca8f9533d8f9 100644 > > --- a/tools/perf/util/evsel.c > > +++ b/tools/perf/util/evsel.c > > @@ -1163,11 +1163,14 @@ void perf_evsel__config(struct evsel *evsel, struct record_opts *opts, > > } > > > > /* > > + * A dummy event never triggers any actual counter and therefore > > + * cannot be used with branch_stack. > > + * > > * For initial_delay, a dummy event is added implicitly. > > * The software event will trigger -EOPNOTSUPP error out, > > * if BRANCH_STACK bit is set. > > */ > > - if (opts->initial_delay && is_dummy_event(evsel)) > > + if (is_dummy_event(evsel)) > > perf_evsel__reset_sample_bit(evsel, BRANCH_STACK); > > } > > > > -- > > 2.26.1.301.g55bc3eb7cb9-goog > > >
| |