[tip:perf/core] perf top: Set display thread COMM to help with debugging

[tip-bot for Arnaldo Carvalho de Melo]

Commit-ID:  1205a2719e52b6b52e0f9c0011554419da0377a0
Gitweb:     https://git.kernel.org/tip/1205a2719e52b6b52e0f9c0011554419da0377a0
Author:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Tue, 6 Aug 2019 11:20:42 -0300
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 12 Aug 2019 16:26:02 -0300

perf top: Set display thread COMM to help with debugging

When we want to attach just to the thread that updates the display it
helps having its COMM stand out, so change it from the default "perf" to
"perf-top-UI".

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-5w0hmlk3zfvysxvpsh763k9w@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/builtin-top.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 1a4615a5f6c9..94e34853a238 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -601,6 +601,8 @@ static void *display_thread_tui(void *arg)
 	 */
 	unshare(CLONE_FS);
 
+	prctl(PR_SET_NAME, "perf-top-UI", 0, 0, 0);
+
 	perf_top__sort_new_samples(top);
 
 	/*
@@ -651,6 +653,8 @@ static void *display_thread(void *arg)
 	 */
 	unshare(CLONE_FS);
 
+	prctl(PR_SET_NAME, "perf-top-UI", 0, 0, 0);
+
 	display_setup_sig();
 	pthread__unblock_sigwinch();
 repeat: