[PATCH 5.0 054/137] perf top: Always sample time to satisfy needs of use of ordered queuing

From: Greg Kroah-Hartman
Date: Wed May 15 2019 - 07:29:53 EST

[ Upstream commit 1e6db2ee86e6a4399fc0ae5689e55e0fd1c43caf ]

Bastian reported broken 'perf top -p PID' command, it won't display any

The problem is that for -p option we monitor single thread, so we don't
enable time in samples, because it's not needed.

However since commit 16c66bc167cc we use ordered queues to stash data
plus later commits added logic for dropping samples in case there's big
load and we don't keep up. All this needs timestamp for sample. Enabling
it unconditionally for perf top.

Reported-by: Bastian Beischer <bastian.beischer@xxxxxxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: bastian beischer <bastian.beischer@xxxxxxxxxxxxxx>
Fixes: 16c66bc167cc ("perf top: Add processing thread")
Link: http://lkml.kernel.org/r/20190415125333.27160-1-jolsa@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
tools/perf/builtin-top.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 616408251e258..63750a711123f 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1393,6 +1393,7 @@ int cmd_top(int argc, const char **argv)
* */
.overwrite = 0,
.sample_time = true,
+ .sample_time_set = true,
.max_stack = sysctl__max_stack(),
.annotation_opts = annotation__default_options,