[tip: perf/core] perf report/top: Improve toggle callchain menu option

[tip-bot2 for Arnaldo Carvalho de Melo]

The following commit has been merged into the perf/core branch of tip:

Commit-ID:     bdc633fec50be7e6856b9dee89af9bb7c5e9a04f
Gitweb:        https://git.kernel.org/tip/bdc633fec50be7e6856b9dee89af9bb7c5e9a04f
Author:        Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate:    Thu, 12 Dec 2019 11:48:23 -03:00
Committer:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Mon, 06 Jan 2020 11:46:10 -03:00

perf report/top: Improve toggle callchain menu option

Taking into account the current status of the callchain, i.e. if folded,
show "Expand", otherwise "Collapse", also show the name of the entry
that will be affected and mention the hotkeys for expanding/collapsing
all callchains below the main entry, the one that appears with/without
callchains.

Reviewed-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-03arm6poo8463k5tfcfp7gkk@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/ui/browsers/hists.c | 54 +++++++++++++++++++++++++++++++--
 tools/perf/util/sort.c         |  3 +--
 tools/perf/util/sort.h         |  2 +-
 3 files changed, 54 insertions(+), 5 deletions(-)

diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index 1b5a599..a4413d9 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -391,6 +391,52 @@ static void hist_entry__init_have_children(struct hist_entry *he)
 	he->init_have_children = true;
 }
 
+static bool hist_browser__selection_has_children(struct hist_browser *browser)
+{
+	struct hist_entry *he = browser->he_selection;
+	struct map_symbol *ms = browser->selection;
+
+	if (!he || !ms)
+		return false;
+
+	if (ms == &he->ms)
+	       return he->has_children;
+
+	return container_of(ms, struct callchain_list, ms)->has_children;
+}
+
+static bool hist_browser__selection_unfolded(struct hist_browser *browser)
+{
+	struct hist_entry *he = browser->he_selection;
+	struct map_symbol *ms = browser->selection;
+
+	if (!he || !ms)
+		return false;
+
+	if (ms == &he->ms)
+	       return he->unfolded;
+
+	return container_of(ms, struct callchain_list, ms)->unfolded;
+}
+
+static char *hist_browser__selection_sym_name(struct hist_browser *browser, char *bf, size_t size)
+{
+	struct hist_entry *he = browser->he_selection;
+	struct map_symbol *ms = browser->selection;
+	struct callchain_list *callchain_entry;
+
+	if (!he || !ms)
+		return NULL;
+
+	if (ms == &he->ms) {
+	       hist_entry__sym_snprintf(he, bf, size, 0);
+	       return bf + 4; // skip the level, e.g. '[k] '
+	}
+
+	callchain_entry = container_of(ms, struct callchain_list, ms);
+	return callchain_list__sym_name(callchain_entry, bf, size, browser->show_dso);
+}
+
 static bool hist_browser__toggle_fold(struct hist_browser *browser)
 {
 	struct hist_entry *he = browser->he_selection;
@@ -2535,12 +2581,14 @@ static int do_toggle_callchain(struct hist_browser *browser, struct popup_action
 
 static int add_callchain_toggle_opt(struct hist_browser *browser, struct popup_action *act, char **optstr)
 {
-	struct hist_entry *he = browser->he_selection;
+	char sym_name[512];
 
-        if (!he->has_children)
+        if (!hist_browser__selection_has_children(browser))
                 return 0;
 
-	if (asprintf(optstr, "Expand/Collapse callchain") < 0)
+	if (asprintf(optstr, "%s [%s] callchain (one level, same as '+' hotkey, use 'e'/'c' for the whole main level entry)",
+		     hist_browser__selection_unfolded(browser) ? "Collapse" : "Expand",
+		     hist_browser__selection_sym_name(browser, sym_name, sizeof(sym_name))) < 0)
 		return 0;
 
 	act->fn = do_toggle_callchain;
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 9fcba28..ab0cfd7 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -324,8 +324,7 @@ static int _hist_entry__sym_snprintf(struct map_symbol *ms,
 	return ret;
 }
 
-static int hist_entry__sym_snprintf(struct hist_entry *he, char *bf,
-				    size_t size, unsigned int width)
+int hist_entry__sym_snprintf(struct hist_entry *he, char *bf, size_t size, unsigned int width)
 {
 	return _hist_entry__sym_snprintf(&he->ms, he->ip,
 					 he->level, bf, size, width);
diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 5aff954..6c862d6 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h
@@ -164,6 +164,8 @@ static __pure inline bool hist_entry__has_callchains(struct hist_entry *he)
 	return he->callchain_size != 0;
 }
 
+int hist_entry__sym_snprintf(struct hist_entry *he, char *bf, size_t size, unsigned int width);
+
 static inline bool hist_entry__has_pairs(struct hist_entry *he)
 {
 	return !list_empty(&he->pairs.node);