perf annotate browser: Allow toggling the visualization of source code lines

Just press 'S' on any assembly line and the source code will be hidden
while the current line remains selected. Press 'S' again to show them
back.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-efmxm5etouebb7es0kkyqqwa@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/ui/browsers/annotate.c

@@ -21,12 +21,16 @@ struct annotate_browser {
 	struct rb_root	  entries;
 	struct rb_node	  *curr_hot;
 	struct objdump_line *selection;
+	int		    nr_asm_entries;
+	int		    nr_entries;
+	bool		    hide_src_code;
 };
 
 struct objdump_line_rb_node {
 	struct rb_node	rb_node;
 	double		percent;
 	u32		idx;
+	int		idx_asm;
 };
 
 static inline
@@ -35,10 +39,22 @@ struct objdump_line_rb_node *objdump_line__rb(struct objdump_line *self)
 	return (struct objdump_line_rb_node *)(self + 1);
 }
 
+static bool objdump_line__filter(struct ui_browser *browser, void *entry)
+{
+	struct annotate_browser *ab = container_of(browser, struct annotate_browser, b);
+
+	if (ab->hide_src_code) {
+		struct objdump_line *ol = list_entry(entry, struct objdump_line, node);
+		return ol->offset == -1;
+	}
+
+	return false;
+}
+
 static void annotate_browser__write(struct ui_browser *self, void *entry, int row)
 {
 	struct annotate_browser *ab = container_of(self, struct annotate_browser, b);
-	struct objdump_line *ol = rb_entry(entry, struct objdump_line, node);
+	struct objdump_line *ol = list_entry(entry, struct objdump_line, node);
 	bool current_entry = ui_browser__is_current_entry(self, row);
 	int width = self->width;
 
@@ -168,6 +184,45 @@ static void annotate_browser__calc_percent(struct annotate_browser *browser,
 	browser->curr_hot = rb_last(&browser->entries);
 }
 
+static bool annotate_browser__toggle_source(struct annotate_browser *browser)
+{
+	struct objdump_line *ol;
+	struct objdump_line_rb_node *olrb;
+	off_t offset = browser->b.index - browser->b.top_idx;
+
+	browser->b.seek(&browser->b, offset, SEEK_CUR);
+	ol = list_entry(browser->b.top, struct objdump_line, node);
+	olrb = objdump_line__rb(ol);
+
+	if (browser->hide_src_code) {
+		if (olrb->idx_asm < offset)
+			offset = olrb->idx;
+
+		browser->b.nr_entries = browser->nr_entries;
+		browser->hide_src_code = false;
+		browser->b.seek(&browser->b, -offset, SEEK_CUR);
+		browser->b.top_idx = olrb->idx - offset;
+		browser->b.index = olrb->idx;
+	} else {
+		if (olrb->idx_asm < 0) {
+			ui_helpline__puts("Only available for assembly lines.");
+			browser->b.seek(&browser->b, -offset, SEEK_CUR);
+			return false;
+		}
+
+		if (olrb->idx_asm < offset)
+			offset = olrb->idx_asm;
+
+		browser->b.nr_entries = browser->nr_asm_entries;
+		browser->hide_src_code = true;
+		browser->b.seek(&browser->b, -offset, SEEK_CUR);
+		browser->b.top_idx = olrb->idx_asm - offset;
+		browser->b.index = olrb->idx_asm;
+	}
+
+	return true;
+}
+
 static int annotate_browser__run(struct annotate_browser *self, int evidx,
 				 int nr_events, void(*timer)(void *arg),
 				 void *arg, int delay_secs)
@@ -175,11 +230,12 @@ static int annotate_browser__run(struct annotate_browser *self, int evidx,
 	struct rb_node *nd = NULL;
 	struct map_symbol *ms = self->b.priv;
 	struct symbol *sym = ms->sym;
+	const char *help = "<-, ESC: exit, TAB/shift+TAB: cycle hottest lines, "
+			   "H: Hottest, -> Line action, S -> Toggle source "
+			   "code view";
 	int key;
 
-	if (ui_browser__show(&self->b, sym->name,
-			     "<- or ESC: exit, TAB/shift+TAB: "
-			     "cycle hottest lines, H: Hottest, -> Line action") < 0)
+	if (ui_browser__show(&self->b, sym->name, help) < 0)
 		return -1;
 
 	annotate_browser__calc_percent(self, evidx);
@@ -234,6 +290,10 @@ static int annotate_browser__run(struct annotate_browser *self, int evidx,
 		case 'H':
 			nd = self->curr_hot;
 			break;
+		case 'S':
+			if (annotate_browser__toggle_source(self))
+				ui_helpline__puts(help);
+			continue;
 		case NEWT_KEY_ENTER:
 		case NEWT_KEY_RIGHT:
 			if (self->selection == NULL) {
@@ -324,6 +384,7 @@ int symbol__tui_annotate(struct symbol *sym, struct map *map, int evidx,
 			.refresh = ui_browser__list_head_refresh,
 			.seek	 = ui_browser__list_head_seek,
 			.write	 = annotate_browser__write,
+			.filter  = objdump_line__filter,
 			.priv	 = &ms,
 		},
 	};
@@ -351,9 +412,14 @@ int symbol__tui_annotate(struct symbol *sym, struct map *map, int evidx,
 		if (browser.b.width < line_len)
 			browser.b.width = line_len;
 		rbpos = objdump_line__rb(pos);
-		rbpos->idx = browser.b.nr_entries++;
+		rbpos->idx = browser.nr_entries++;
+		if (pos->offset != -1)
+			rbpos->idx_asm = browser.nr_asm_entries++;
+		else
+			rbpos->idx_asm = -1;
 	}
 
+	browser.b.nr_entries = browser.nr_entries;
 	browser.b.entries = &notes->src->source,
 	browser.b.width += 18; /* Percentage */
 	ret = annotate_browser__run(&browser, evidx, nr_events,