Re: [PATCH 13/35] perf tools: Add machine_pid and vcpu to perf_sample

Ian Rogers
2022-07-20T00:37:16Z

On Mon, Jul 11, 2022 at 2:33 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> When parsing a sample with a sample ID, copy machine_pid and vcpu from
> perf_sample_id to perf_sample.
>
> Note, machine_pid will be zero when unused, so only a non-zero value
> represents a guest machine. vcpu should be ignored if machine_pid is zero.
>
> Note also, machine_pid is used with events that have come from injecting a
> guest perf.data file, however guest events recorded on the host (i.e. using
> perf kvm) have the (QEMU) hypervisor process pid to identify them - refer
> machines__find_for_cpumode().
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>

Acked-by: Ian Rogers <irogers@google.com>

Thanks,
Ian

> ---
> tools/perf/util/event.h | 2 ++
> tools/perf/util/evlist.c | 14 +++++++++++++-
> tools/perf/util/evsel.c | 1 +
> 3 files changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
> index cdd72e05fd28..a660f304f83c 100644
> --- a/tools/perf/util/event.h
> +++ b/tools/perf/util/event.h
> @@ -148,6 +148,8 @@ struct perf_sample {
> u64 code_page_size;
> u64 cgroup;
> u32 flags;
> + u32 machine_pid;
> + u32 vcpu;
> u16 insn_len;
> u8 cpumode;
> u16 misc;
> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> index 03fbe151b0c4..64f5a8074c0c 100644
> --- a/tools/perf/util/evlist.c
> +++ b/tools/perf/util/evlist.c
> @@ -1507,10 +1507,22 @@ int evlist__start_workload(struct evlist *evlist)
> int evlist__parse_sample(struct evlist *evlist, union perf_event *event, struct perf_sample *sample)
> {
> struct evsel *evsel = evlist__event2evsel(evlist, event);
> + int ret;
>
> if (!evsel)
> return -EFAULT;
> - return evsel__parse_sample(evsel, event, sample);
> + ret = evsel__parse_sample(evsel, event, sample);
> + if (ret)
> + return ret;
> + if (perf_guest && sample->id) {
> + struct perf_sample_id *sid = evlist__id2sid(evlist, sample->id);
> +
> + if (sid) {
> + sample->machine_pid = sid->machine_pid;
> + sample->vcpu = sid->vcpu.cpu;
> + }
> + }
> + return 0;
> }
>
> int evlist__parse_sample_timestamp(struct evlist *evlist, union perf_event *event, u64 *timestamp)
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index 9a30ccb7b104..14396ea5a968 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -2365,6 +2365,7 @@ int evsel__parse_sample(struct evsel *evsel, union perf_event *event,
> data->misc = event->header.misc;
> data->id = -1ULL;
> data->data_src = PERF_MEM_DATA_SRC_NONE;
> + data->vcpu = -1;
>
> if (event->header.type != PERF_RECORD_SAMPLE) {
> if (!evsel->core.attr.sample_id_all)
> --
> 2.25.1
>