perf annotate: Fix sample events lost in stdio mode

In hist__find_annotations(), since different 'struct hist_entry' entries
may point to same symbol, we free notes->src to signal already processed
this symbol in stdio mode; when annotate, entry will skipped if
notes->src is NULL to avoid repeated output.

However, there is a problem, for example, run the following command:

 # perf record -e branch-misses -e branch-instructions -a sleep 1

perf.data file contains different types of sample event.

If the same IP sample event exists in branch-misses and branch-instructions,
this event uses the same symbol. When annotate branch-misses events, notes->src
corresponding to this event is set to null, as a result, when annotate
branch-instructions events, this event is skipped and no annotate is output.

Solution of this patch is to remove zfree in hists__find_annotations and
change sort order to "dso,symbol" to avoid duplicate output when different
processes correspond to the same symbol.

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: zhangjinhao2@huawei.com
Link: http://lore.kernel.org/lkml/20210319123527.173883-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-annotate.c

@@ -374,13 +374,6 @@ static void hists__find_annotations(struct hists *hists,
 		} else {
 			hist_entry__tty_annotate(he, evsel, ann);
 			nd = rb_next(nd);
-			/*
-			 * Since we have a hist_entry per IP for the same
-			 * symbol, free he->ms.sym->src to signal we already
-			 * processed this symbol.
-			 */
-			zfree(&notes->src->cycles_hist);
-			zfree(&notes->src);
 		}
 	}
 }
@@ -623,14 +616,22 @@ int cmd_annotate(int argc, const char **argv)
 
 	setup_browser(true);
 
-	if ((use_browser == 1 || annotate.use_stdio2) && annotate.has_br_stack) {
+	/*
+	 * Events of different processes may correspond to the same
+	 * symbol, we do not care about the processes in annotate,
+	 * set sort order to avoid repeated output.
+	 */
+	sort_order = "dso,symbol";
+
+	/*
+	 * Set SORT_MODE__BRANCH so that annotate display IPC/Cycle
+	 * if branch info is in perf data in TUI mode.
+	 */
+	if ((use_browser == 1 || annotate.use_stdio2) && annotate.has_br_stack)
 		sort__mode = SORT_MODE__BRANCH;
-		if (setup_sorting(annotate.session->evlist) < 0)
-			usage_with_options(annotate_usage, options);
-	} else {
-		if (setup_sorting(NULL) < 0)
-			usage_with_options(annotate_usage, options);
-	}
+
+	if (setup_sorting(NULL) < 0)
+		usage_with_options(annotate_usage, options);
 
 	ret = __cmd_annotate(&annotate);