Em Fri, Jun 24, 2022 at 04:13:09PM -0700, Namhyung Kim escreveu:
> As offcpu-time event is synthesized at the end, it could not get the
> all the sample info. Define OFFCPU_SAMPLE_TYPES for allowed ones and
> mask out others in evsel__config() to prevent parse errors.
>
> Because perf sample parsing assumes a specific ordering with the
> sample types, setting unsupported one would make it fail to read
> data like perf record -d/--data.
> Fixes: edc41a1099c2 ("perf record: Enable off-cpu analysis with BPF")
Thanks, applied.
- Arnaldo
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
> tools/perf/util/bpf_off_cpu.c | 7 ++++++-
> tools/perf/util/evsel.c | 9 +++++++++
> tools/perf/util/off_cpu.h | 9 +++++++++
> 3 files changed, 24 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/bpf_off_cpu.c b/tools/perf/util/bpf_off_cpu.c
> index b73e84a02264..f289b7713598 100644
> --- a/tools/perf/util/bpf_off_cpu.c
> +++ b/tools/perf/util/bpf_off_cpu.c
> @@ -265,6 +265,12 @@ int off_cpu_write(struct perf_session *session)
>
> sample_type = evsel->core.attr.sample_type;
>
> + if (sample_type & ~OFFCPU_SAMPLE_TYPES) {
> + pr_err("not supported sample type: %llx\n",
> + (unsigned long long)sample_type);
> + return -1;
> + }
> +
> if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) {
> if (evsel->core.id)
> sid = evsel->core.id[0];
> @@ -319,7 +325,6 @@ int off_cpu_write(struct perf_session *session)
> }
> if (sample_type & PERF_SAMPLE_CGROUP)
> data.array[n++] = key.cgroup_id;
> - /* TODO: handle more sample types */
>
> size = n * sizeof(u64);
> data.hdr.size = size;
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index ce499c5da8d7..094b0a9c0bc0 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -48,6 +48,7 @@
> #include "util.h"
> #include "hashmap.h"
> #include "pmu-hybrid.h"
> +#include "off_cpu.h"
> #include "../perf-sys.h"
> #include "util/parse-branch-options.h"
> #include <internal/xyarray.h>
> @@ -1102,6 +1103,11 @@ static void evsel__set_default_freq_period(struct record_opts *opts,
> }
> }
>
> +static bool evsel__is_offcpu_event(struct evsel *evsel)
> +{
> + return evsel__is_bpf_output(evsel) && !strcmp(evsel->name, OFFCPU_EVENT);
> +}
> +
> /*
> * The enable_on_exec/disabled value strategy:
> *
> @@ -1366,6 +1372,9 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts,
> */
> if (evsel__is_dummy_event(evsel))
> evsel__reset_sample_bit(evsel, BRANCH_STACK);
> +
> + if (evsel__is_offcpu_event(evsel))
> + evsel->core.attr.sample_type &= OFFCPU_SAMPLE_TYPES;
> }
>
> int evsel__set_filter(struct evsel *evsel, const char *filter)
> diff --git a/tools/perf/util/off_cpu.h b/tools/perf/util/off_cpu.h
> index 548008f74d42..2dd67c60f211 100644
> --- a/tools/perf/util/off_cpu.h
> +++ b/tools/perf/util/off_cpu.h
> @@ -1,6 +1,8 @@
> #ifndef PERF_UTIL_OFF_CPU_H
> #define PERF_UTIL_OFF_CPU_H
>
> +#include <linux/perf_event.h>
> +
> struct evlist;
> struct target;
> struct perf_session;
> @@ -8,6 +10,13 @@ struct record_opts;
>
> #define OFFCPU_EVENT "offcpu-time"
>
> +#define OFFCPU_SAMPLE_TYPES (PERF_SAMPLE_IDENTIFIER | PERF_SAMPLE_IP | \
> + PERF_SAMPLE_TID | PERF_SAMPLE_TIME | \
> + PERF_SAMPLE_ID | PERF_SAMPLE_CPU | \
> + PERF_SAMPLE_PERIOD | PERF_SAMPLE_CALLCHAIN | \
> + PERF_SAMPLE_CGROUP)
> +
> +
> #ifdef HAVE_BPF_SKEL
> int off_cpu_prepare(struct evlist *evlist, struct target *target,
> struct record_opts *opts);
> --
> 2.37.0.rc0.161.g10f37bed90-goog
--
- Arnaldo
