From: Adrian Hunter <adrian.hun...@intel.com> The 'idx' member was added as preparation for AUX area sampling. Add a comment to describe why.
Signed-off-by: Adrian Hunter <adrian.hun...@intel.com> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Michael Petlan <mpet...@redhat.com> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Peter Zijlstra <pet...@infradead.org> Link: http://lkml.kernel.org/r/83ff264f-84c3-5372-8976-dd9293d20...@intel.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/evsel.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index 9cd6e3ae479a..efe08065838f 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -23,6 +23,13 @@ struct perf_sample_id { struct hlist_node node; u64 id; struct evsel *evsel; + /* + * 'idx' will be used for AUX area sampling. A sample will have AUX area + * data that will be queued for decoding, where there are separate + * queues for each CPU (per-cpu tracing) or task (per-thread tracing). + * The sample ID can be used to lookup 'idx' which is effectively the + * queue number. + */ int idx; int cpu; pid_t tid; -- 2.21.0
