perf record: Add --synth option

Add an option to control the synthesizing behavior.

    --synth <no|all|task|mmap|cgroup>
                      Fine-tune event synthesis: default=all

This can be useful when we know it doesn't need some synthesis like
in a specific usecase and/or when using pipe:

  $ perf record -a --all-cgroups --synth cgroup -o- sleep 1 | \
  > perf report -i- -s cgroup

Committer notes:

Added a clarification to the man page entry for --synth that this is
about pre-existing threads.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https //lore.kernel.org/r/20210811044658.1313391-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/tools/perf/util/synthetic-events.h b/tools/perf/util/synthetic-events.h
index 44f72d56ca4d..c931433bacbf 100644
--- a/tools/perf/util/synthetic-events.h
+++ b/tools/perf/util/synthetic-events.h
@@ -27,6 +27,18 @@ struct target;
 
 union perf_event;
 
+enum perf_record_synth {
+	PERF_SYNTH_TASK		= 1 << 0,
+	PERF_SYNTH_MMAP		= 1 << 1,
+	PERF_SYNTH_CGROUP	= 1 << 2,
+
+	/* last element */
+	PERF_SYNTH_MAX		= 1 << 3,
+};
+#define PERF_SYNTH_ALL  (PERF_SYNTH_MAX - 1)
+
+int parse_synth_opt(char *str);
+
 typedef int (*perf_event__handler_t)(struct perf_tool *tool, union perf_event *event,
 				     struct perf_sample *sample, struct machine *machine);