[PATCH v2] perf trace: Skip unnecessary synthesis for summary-only mode

[Namhyung Kim]

It needs to synthesize task info for the comm name.  The mmap
information is only needed for callchain symbolization which is not used
by the summary mode.  Also total or cgroup summary mode don't require
the task info.  Let's skip the processing if possible.

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
v2) minimize the diff  (Ian)

 tools/perf/builtin-trace.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index f487fbaa0ad60028..d121640ace6e1456 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -2004,9 +2004,13 @@ static int trace__symbols_init(struct trace *trace, int argc, const char **argv,
 	if (err < 0)
 		goto out;
 
+	if (trace->summary_only && trace->summary_mode != SUMMARY__BY_THREAD)
+		goto out;
+
 	err = __machine__synthesize_threads(trace->host, &trace->tool, &trace->opts.target,
 					    evlist->core.threads, trace__tool_process,
-					    /*needs_mmap=*/callchain_param.enabled,
+					    /*needs_mmap=*/callchain_param.enabled &&
+							   !trace->summary_only,
 					    /*mmap_data=*/false,
 					    /*nr_threads_synthesize=*/1);
 out:
-- 
2.53.0.1213.gd9a14994de-goog