perf ui/tui: Protect windows by ui__lock

Sometimes perf top TUI breaks display with concurrent help/input window
and pr_* messages since they're not protected by ui__lock.

You can check it by pressing (and not releasing) 'h' key on a "perf top
-vvv" TUI session.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1388036284-32342-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/ui/tui/util.c b/tools/perf/ui/tui/util.c
index 092902e..bf890f7 100644 (file)
--- a/tools/perf/ui/tui/util.c
+++ b/tools/perf/ui/tui/util.c
@@ -92,6 +92,8 @@ int ui_browser__input_window(const char *title, const char *text, char *input,
                t = sep + 1;
        }
 
+       pthread_mutex_lock(&ui__lock);
+
        max_len += 2;
        nr_lines += 8;
        y = SLtt_Screen_Rows / 2 - nr_lines / 2;
@@ -120,13 +122,19 @@ int ui_browser__input_window(const char *title, const char *text, char *input,
        SLsmg_write_nstring((char *)exit_msg, max_len);
        SLsmg_refresh();
 
+       pthread_mutex_unlock(&ui__lock);
+
        x += 2;
        len = 0;
        key = ui__getch(delay_secs);
        while (key != K_TIMER && key != K_ENTER && key != K_ESC) {
+               pthread_mutex_lock(&ui__lock);
+
                if (key == K_BKSPC) {
-                       if (len == 0)
+                       if (len == 0) {
+                               pthread_mutex_unlock(&ui__lock);
                                goto next_key;
+                       }
                        SLsmg_gotorc(y, x + --len);
                        SLsmg_write_char(' ');
                } else {
@@ -136,6 +144,8 @@ int ui_browser__input_window(const char *title, const char *text, char *input,
                }
                SLsmg_refresh();
 
+               pthread_mutex_unlock(&ui__lock);
+
                /* XXX more graceful overflow handling needed */
                if (len == sizeof(buf) - 1) {
                        ui_helpline__push("maximum size of symbol name reached!");
@@ -174,6 +184,8 @@ int ui__question_window(const char *title, const char *text,
                t = sep + 1;
        }
 
+       pthread_mutex_lock(&ui__lock);
+
        max_len += 2;
        nr_lines += 4;
        y = SLtt_Screen_Rows / 2 - nr_lines / 2,
@@ -195,6 +207,9 @@ int ui__question_window(const char *title, const char *text,
        SLsmg_gotorc(y + nr_lines - 1, x);
        SLsmg_write_nstring((char *)exit_msg, max_len);
        SLsmg_refresh();
+
+       pthread_mutex_unlock(&ui__lock);
+
        return ui__getch(delay_secs);
 }
 
@@ -215,9 +230,7 @@ static int __ui__warning(const char *title, const char *format, va_list args)
        if (vasprintf(&s, format, args) > 0) {
                int key;
 
-               pthread_mutex_lock(&ui__lock);
                key = ui__question_window(title, s, "Press any key...", 0);
-               pthread_mutex_unlock(&ui__lock);
                free(s);
                return key;
        }