[PATCH v6 2/3] perf tools annotate: Fix a crash/hang when switch disassemble and source view

[Tianyou Li <tianyou.li@intel.com>]

When perf report with annotation, press 'TAB' to navigate among hot lines,
press 's' to switch on the source view, then press 'TAB' again, the perf
report could crash or hang. The 'nd' and 'browser->curr_hot' need to be
updated when switch the disassemble and source view.

Signed-off-by: Tianyou Li <tianyou.li@intel.com>
---
 tools/perf/ui/browsers/annotate.c | 35 ++++++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c
index 8fe699f98542..32da310b3b62 100644
--- a/tools/perf/ui/browsers/annotate.c
+++ b/tools/perf/ui/browsers/annotate.c
@@ -852,6 +852,30 @@ static void annotate_browser__debuginfo_warning(struct annotate_browser *browser
 	}
 }
 
+static u32 rb_node__get_idx_asm(struct rb_node *nd)
+{
+	struct annotation_line *al = NULL;
+
+	if (nd == NULL)
+		return 0;
+
+	al = rb_entry(nd, struct annotation_line, rb_node);
+
+	return al->idx_asm;
+}
+
+static struct rb_node *annotate_browser__rb_node_by_idx_asm(struct annotate_browser *browser,
+									u32 idx_asm)
+{
+	struct annotation_line *al = NULL;
+
+	if (idx_asm == 0)
+		return NULL;
+
+	al = annotate_browser__find_new_asm_line(browser, idx_asm);
+	return al ? &al->rb_node : NULL;
+}
+
 static int annotate_browser__run(struct annotate_browser *browser,
 				 struct evsel *evsel,
 				 struct hist_browser_timer *hbt)
@@ -969,8 +993,17 @@ static int annotate_browser__run(struct annotate_browser *browser,
 			nd = browser->curr_hot;
 			break;
 		case 's':
-			if (annotate_browser__toggle_source(browser, evsel))
+			u32 idx_asm_nd = rb_node__get_idx_asm(nd);
+			u32 idx_asm_curr_hot = rb_node__get_idx_asm(browser->curr_hot);
+
+			if (annotate_browser__toggle_source(browser, evsel)) {
 				ui_helpline__puts(help);
+				/* Update the annotation browser's rb_tree, and reset the nd */
+				annotate_browser__calc_percent(browser, evsel);
+				nd = annotate_browser__rb_node_by_idx_asm(browser, idx_asm_nd);
+				browser->curr_hot = annotate_browser__rb_node_by_idx_asm(browser,
+							idx_asm_curr_hot);
+			}
 			annotate__scnprintf_title(hists, title, sizeof(title));
 			annotate_browser__show(browser, title, help);
 			continue;
-- 
2.47.1