perf hists browser: Allow annotating entries in callchains

Instead of annotating just the top level hist_entry, allow instead
annotating a map_symbol, i.e. the top level hist_entry or one of the
callchains for which there were samples.

Suggested-by: Stephane Eranian <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: Don Zickus <[e-mail]>
Cc: Frederic Weisbecker <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Link: http://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/ui/browsers/annotate.c

···
 	return key;
 }
 
+int map_symbol__tui_annotate(struct map_symbol *ms, struct perf_evsel *evsel,
+			     struct hist_browser_timer *hbt)
+{
+	return symbol__tui_annotate(ms->sym, ms->map, evsel, hbt);
+}
+
 int hist_entry__tui_annotate(struct hist_entry *he, struct perf_evsel *evsel,
 			     struct hist_browser_timer *hbt)
 {
-	return symbol__tui_annotate(he->ms.sym, he->ms.map, evsel, hbt);
+	return map_symbol__tui_annotate(&he->ms, evsel, hbt);
 }
 
 static void annotate_browser__mark_jump_targets(struct annotate_browser *browser,

tools/perf/ui/browsers/hists.c

···
 		if (choice == annotate || choice == annotate_t || choice == annotate_f) {
 			struct hist_entry *he;
 			struct annotation *notes;
+			struct map_symbol ms;
 			int err;
 do_annotate:
 			if (!objdump_path && perf_session_env__lookup_objdump(env))
···
 			if (he == NULL)
 				continue;
 
-			/*
-			 * we stash the branch_info symbol + map into the
-			 * the ms so we don't have to rewrite all the annotation
-			 * code to use branch_info.
-			 * in branch mode, the ms struct is not used
-			 */
 			if (choice == annotate_f) {
-				he->ms.sym = he->branch_info->from.sym;
-				he->ms.map = he->branch_info->from.map;
-			}  else if (choice == annotate_t) {
-				he->ms.sym = he->branch_info->to.sym;
-				he->ms.map = he->branch_info->to.map;
+				ms.map = he->branch_info->from.map;
+				ms.sym = he->branch_info->from.sym;
+			} else if (choice == annotate_t) {
+				ms.map = he->branch_info->to.map;
+				ms.sym = he->branch_info->to.sym;
+			} else {
+				ms = *browser->selection;
 			}
 
-			notes = symbol__annotation(he->ms.sym);
+			notes = symbol__annotation(ms.sym);
 			if (!notes->src)
 				continue;
 
-			err = hist_entry__tui_annotate(he, evsel, hbt);
+			err = map_symbol__tui_annotate(&ms, evsel, hbt);
 			/*
 			 * offer option to annotate the other branch source or target
 			 * (if they exists) when returning from annotate

tools/perf/util/hist.h

···
 
 #ifdef HAVE_SLANG_SUPPORT
 #include "../ui/keysyms.h"
+int map_symbol__tui_annotate(struct map_symbol *ms, struct perf_evsel *evsel,
+			     struct hist_browser_timer *hbt);
+
 int hist_entry__tui_annotate(struct hist_entry *he, struct perf_evsel *evsel,
 			     struct hist_browser_timer *hbt);
 
···
 				  struct hist_browser_timer *hbt __maybe_unused,
 				  float min_pcnt __maybe_unused,
 				  struct perf_session_env *env __maybe_unused)
+{
+	return 0;
+}
+static inline int map_symbol__tui_annotate(struct map_symbol *ms __maybe_unused,
+					   struct perf_evsel *evsel __maybe_unused,
+					   struct hist_browser_timer *hbt __maybe_unused)
 {
 	return 0;
 }