perf report: Support a new key to reload the browser

Sometimes we may need to reload the browser to update the output since
some options are changed.

This patch creates a new key K_RELOAD. Once the __cmd_report() returns
K_RELOAD, it would repeat the whole process, such as, read samples from
data file, sort the data and display in the browser.

 v5:
 ---
 1. Fix the 'make NO_SLANG=1' error. Define K_RELOAD in util/hist.h.
 2. Skip setup_sorting() in repeat path if last key is K_RELOAD.

 v4:
 ---
 Need to quit in perf_evsel_menu__run if key is K_RELOAD.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200220013616.19916-3-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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:
@@ -1480,7 +1480,7 @@ int cmd_report(int argc, const char **argv)
 		sort_order = sort_tmp;
 	}
 
-	if ((last_key != K_SWITCH_INPUT_DATA) &&
+	if ((last_key != K_SWITCH_INPUT_DATA && last_key != K_RELOAD) &&
 	    (setup_sorting(session->evlist) < 0)) {
 		if (sort_order)
 			parse_options_usage(report_usage, options, "s", 1);
@@ -1559,7 +1559,7 @@ 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);
 		last_key = K_SWITCH_INPUT_DATA;
 		goto repeat;

tools/perf/ui/browsers/hists.c

@@ -3495,6 +3495,7 @@ static int perf_evsel_menu__run(struct evsel_menu *menu,
 					pos = perf_evsel__prev(pos);
 				goto browse_hists;
 			case K_SWITCH_INPUT_DATA:
+			case K_RELOAD:
 			case 'q':
 			case CTRL('c'):
 				goto out;

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_ */

tools/perf/util/hist.h

@@ -536,6 +536,7 @@ static inline int block_hists_tui_browse(struct block_hist *bh __maybe_unused,
 #define K_LEFT  -1000
 #define K_RIGHT -2000
 #define K_SWITCH_INPUT_DATA -3000
+#define K_RELOAD -4000
 #endif
 
 unsigned int hists__sort_list_width(struct hists *hists);