[PATCH 3.18 38/68] perf session: Dont rely on evlist in pipe mode

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Carrillo-Cisneros <redacted>


[ Upstream commit 0973ad97c187e06aece61f685b9c3b2d93290a73 ]

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 <redacted>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <redacted>
Cc: He Kuang <redacted>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <redacted>
Cc: Stephane Eranian <redacted>
Cc: Wang Nan <redacted>
Link: http://lkml.kernel.org/r/20170410201432.24807-6-davidcc@google.com
[ Check if file != NULL in perf_session__new(), like when used by builtin-top.c ]
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
Signed-off-by: Sasha Levin <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 tools/perf/util/session.c |   16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c

@@ -108,8 +108,14 @@ struct perf_session *perf_session__new(s
 			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);
+			}
 		}
 	}
 

@@ -122,7 +128,11 @@ struct perf_session *perf_session__new(s
 			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 || !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;