perf report/top: Do not offer annotation for symbols without samples

This can happen in the --children mode, i.e. the default mode when
callchains are present, where one of the main entries may be a callchain
entry with no samples.

So far we were not providing any information about why an annotation
couldn't be provided even offering the Annotation option in the popup
menu.

Work is needed to allow for no-samples "annotation', i.e. to show the
disassembly anyway and allow for navigation, etc.

Reviewed-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jin Yao <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: https://lkml.kernel.org/n/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 10 insertions, 1 deletions

diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index 8776b1cb29b7..3bec8de89880 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -2465,7 +2465,8 @@ add_annotate_opt(struct hist_browser *browser __maybe_unused,
 		 struct popup_action *act, char **optstr,
 		 struct map_symbol *ms)
 {
-	if (ms->sym == NULL || ms->map->dso->annotate_warned)
+	if (ms->sym == NULL || ms->map->dso->annotate_warned ||
+	    symbol__annotation(ms->sym)->src == NULL)
 		return 0;
 
 	if (asprintf(optstr, "Annotate %s", ms->sym->name) < 0)
@@ -3031,6 +3032,14 @@ do_hotkey:		 // key came straight from options ui__popup_menu()
 			    browser->selection->map->dso->annotate_warned)
 				continue;
 
+			if (symbol__annotation(browser->selection->sym)->src == NULL) {
+				ui_browser__warning(&browser->b, delay_secs * 2,
+						    "No samples for the \"%s\" symbol.\n\n"
+						    "Probably appeared just in a callchain",
+						    browser->selection->sym->name);
+				continue;
+			}
+
 			actions->ms.map = browser->selection->map;
 			actions->ms.sym = browser->selection->sym;
 			do_annotate(browser, actions);