[tip: perf/urgent] perf top: Support --group-sort-idx to change the sort order

[tip-bot2 for Jin Yao]

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID:     df7deb2cceef0546ab2115702da3421b7c61a8c0
Gitweb:        https://git.kernel.org/tip/df7deb2cceef0546ab2115702da3421b7c61a8c0
Author:        Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
AuthorDate:    Wed, 25 Mar 2020 06:07:10 +08:00
Committer:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Fri, 03 Apr 2020 09:37:55 -03:00

perf top: Support --group-sort-idx to change the sort order

'perf report' supports the option --group-sort-idx, which sorts the
output by the event at the index n in event group.

For example:

  perf record -e cycles,instructions,cache-misses
  perf report --group --group-sort-idx 2 --stdio

The perf-report output is sorted by cache-misses.

This patch supports --group-sort-idx in perf-top.

For example:

  perf top --group -e cycles,instructions,cache-misses --group-sort-idx 2

The perf-top output is sorted by cache-misses.

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
Suggested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lore.kernel.org/lkml/20200324220711.6025-1-yao.jin@xxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/Documentation/perf-top.txt | 5 +++++
 tools/perf/builtin-top.c              | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/tools/perf/Documentation/perf-top.txt b/tools/perf/Documentation/perf-top.txt
index ddab103..487737a 100644
--- a/tools/perf/Documentation/perf-top.txt
+++ b/tools/perf/Documentation/perf-top.txt
@@ -53,6 +53,11 @@ Default is to monitor all CPUS.
 --group::
         Put the counters into a counter group.
 
+--group-sort-idx::
+	Sort the output by the event at the index n in group. If n is invalid,
+	sort by the first event. It can support multiple groups with different
+	amount of events. WARNING: This should be used on grouped events.
+
 -F <freq>::
 --freq=<freq>::
 	Profile at this frequency. Use 'max' to use the currently maximum
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 02ea2cf..9ff7943 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1560,6 +1560,10 @@ int cmd_top(int argc, const char **argv)
 		    "Record namespaces events"),
 	OPT_BOOLEAN(0, "all-cgroups", &opts->record_cgroup,
 		    "Record cgroup events"),
+	OPT_INTEGER(0, "group-sort-idx", &symbol_conf.group_sort_idx,
+		    "Sort the output by the event at the index n in group. "
+		    "If n is invalid, sort by the first event. "
+		    "WARNING: should be used on grouped events."),
 	OPTS_EVSWITCH(&top.evswitch),
 	OPT_END()
 	};