[PATCH 5/7] perf session: don't rely on evlist in pipe mode

[David Carrillo-Cisneros]

Session sets a number parameters that rely on evlist. These parameters
are not used in pipe-mode and should not be set, since evlist is
unavailable. Fix that.

Signed-off-by: David Carrillo-Cisneros <davidcc@xxxxxxxxxx>
---
 tools/perf/util/session.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index a25302bc55a8..db554b7461b8 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -140,8 +140,14 @@ struct perf_session *perf_session__new(struct perf_data_file *file,
 			if (perf_session__open(session) < 0)
 				goto out_close;
 
-			perf_session__set_id_hdr_size(session);
-			perf_session__set_comm_exec(session);
+			/*
+			 * set session attributes that are present in perf.data
+			 * but not in pipe-mode.
+			 */
+			if (!file->is_pipe) {
+				perf_session__set_id_hdr_size(session);
+				perf_session__set_comm_exec(session);
+			}
 		}
 	} else  {
 		session->machines.host.env = &perf_env;
@@ -156,7 +162,11 @@ struct perf_session *perf_session__new(struct perf_data_file *file,
 			pr_warning("Cannot read kernel map\n");
 	}
 
-	if (tool && tool->ordering_requires_timestamps &&
+	/*
+	 * In pipe-mode, evlist is empty until PERF_RECORD_HEADER_ATTR is
+	 * processed, so perf_evlist__sample_id_all is not meaningful here.
+	 */
+	if (!file->is_pipe && tool && tool->ordering_requires_timestamps &&
 	    tool->ordered_events && !perf_evlist__sample_id_all(session->evlist)) {
 		dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n");
 		tool->ordered_events = false;
-- 
2.12.2.715.g7642488e1d-goog