[PATCH v1 2/2] perf report: support hotkey to let user select any event in group for sorting

[Jin Yao]

When performing "perf report --group", it shows the event group information
together. In previous patch, we have supported a new option "--group-sort-idx"
to sort the output by the event at the index n in event group.

It would be nice if we can use a hotkey in browser to select a event
for sorting.

For example,

  # perf report --group

 Samples: 12K of events 'cpu/instructions,period=2000003/, cpu/cpu-cycles,period=200003/, ...
                        Overhead  Command    Shared Object            Symbol
  92.19%  98.68%   0.00%  93.30%  mgen       mgen                     [.] LOOP1
   3.12%   0.29%   0.00%   0.16%  gsd-color  libglib-2.0.so.0.5600.4  [.] 0x0000000000049515
   1.56%   0.03%   0.00%   0.04%  gsd-color  libglib-2.0.so.0.5600.4  [.] 0x00000000000494b7
   1.56%   0.01%   0.00%   0.00%  gsd-color  libglib-2.0.so.0.5600.4  [.] 0x00000000000494ce
   1.56%   0.00%   0.00%   0.00%  mgen       [kernel.kallsyms]        [k] task_tick_fair
   0.00%   0.15%   0.00%   0.04%  perf       [kernel.kallsyms]        [k] smp_call_function_single
   0.00%   0.13%   0.00%   6.08%  swapper    [kernel.kallsyms]        [k] intel_idle
   0.00%   0.03%   0.00%   0.00%  gsd-color  libglib-2.0.so.0.5600.4  [.] g_main_context_check
   0.00%   0.03%   0.00%   0.00%  swapper    [kernel.kallsyms]        [k] apic_timer_interrupt
   0.00%   0.03%   0.00%   0.00%  swapper    [kernel.kallsyms]        [k] check_preempt_curr

When user press hotkey '3' (event index, starting from 0), it indicates
to sort output by the fourth event in group.

  Samples: 12K of events 'cpu/instructions,period=2000003/, cpu/cpu-cycles,period=200003/, ...
                        Overhead  Command    Shared Object            Symbol
  92.19%  98.68%   0.00%  93.30%  mgen       mgen                     [.] LOOP1
   0.00%   0.13%   0.00%   6.08%  swapper    [kernel.kallsyms]        [k] intel_idle
   3.12%   0.29%   0.00%   0.16%  gsd-color  libglib-2.0.so.0.5600.4  [.] 0x0000000000049515
   0.00%   0.00%   0.00%   0.06%  swapper    [kernel.kallsyms]        [k] hrtimer_start_range_ns
   1.56%   0.03%   0.00%   0.04%  gsd-color  libglib-2.0.so.0.5600.4  [.] 0x00000000000494b7
   0.00%   0.15%   0.00%   0.04%  perf       [kernel.kallsyms]        [k] smp_call_function_single
   0.00%   0.00%   0.00%   0.02%  mgen       [kernel.kallsyms]        [k] update_curr
   0.00%   0.00%   0.00%   0.02%  mgen       [kernel.kallsyms]        [k] apic_timer_interrupt
   0.00%   0.00%   0.00%   0.02%  mgen       [kernel.kallsyms]        [k] native_apic_msr_eoi_write
   0.00%   0.00%   0.00%   0.02%  mgen       [kernel.kallsyms]        [k] __update_load_avg_se

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
 tools/perf/builtin-report.c    |  4 ++--
 tools/perf/ui/browsers/hists.c | 21 ++++++++++++++++++++-
 tools/perf/ui/keysyms.h        |  1 +
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 729cf7611d8a..02178fc54d67 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -635,7 +635,7 @@ static int report__browse_hists(struct report *rep)
 		 * Usually "ret" is the last pressed key, and we only
 		 * care if the key notifies us to switch data file.
 		 */
-		if (ret != K_SWITCH_INPUT_DATA)
+		if (ret != K_SWITCH_INPUT_DATA && ret != K_RELOAD)
 			ret = 0;
 		break;
 	case 2:
@@ -1538,7 +1538,7 @@ int cmd_report(int argc, const char **argv)
 	sort__setup_elide(stdout);
 
 	ret = __cmd_report(&report);
-	if (ret == K_SWITCH_INPUT_DATA) {
+	if (ret == K_SWITCH_INPUT_DATA || ret == K_RELOAD) {
 		perf_session__delete(session);
 		goto repeat;
 	} else
diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index d4d3558fdef4..1de2456f27c3 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -2876,7 +2876,8 @@ static int perf_evsel__hists_browse(struct evsel *evsel, int nr_events,
 	"s             Switch to another data file in PWD\n"
 	"t             Zoom into current Thread\n"
 	"V             Verbose (DSO names in callchains, etc)\n"
-	"/             Filter symbol by name";
+	"/             Filter symbol by name\n"
+	"0-9           Sort by event n in group";
 	static const char top_help[] = HIST_BROWSER_HELP_COMMON
 	"P             Print histograms to perf.hist.N\n"
 	"t             Zoom into current Thread\n"
@@ -2937,6 +2938,24 @@ static int perf_evsel__hists_browse(struct evsel *evsel, int nr_events,
 			 * go to the next or previous
 			 */
 			goto out_free_stack;
+		case '0':
+		case '1':
+		case '2':
+		case '3':
+		case '4':
+		case '5':
+		case '6':
+		case '7':
+		case '8':
+		case '9':
+			symbol_conf.group_sort_idx = key - '0';
+			if (!symbol_conf.event_group ||
+			    symbol_conf.group_sort_idx >= evsel->core.nr_members) {
+				continue;
+			}
+
+			key = K_RELOAD;
+			goto out_free_stack;
 		case 'a':
 			if (!hists__has(hists, sym)) {
 				ui_browser__warning(&browser->b, delay_secs * 2,
diff --git a/tools/perf/ui/keysyms.h b/tools/perf/ui/keysyms.h
index fbfac29077f2..04cc4e5c031f 100644
--- a/tools/perf/ui/keysyms.h
+++ b/tools/perf/ui/keysyms.h
@@ -25,5 +25,6 @@
 #define K_ERROR	 -2
 #define K_RESIZE -3
 #define K_SWITCH_INPUT_DATA -4
+#define K_RELOAD -5
 
 #endif /* _PERF_KEYSYMS_H_ */
-- 
2.17.1