path: root/tools/perf/util/ui/helpline.c
diff options
authorArnaldo Carvalho de Melo <acme@redhat.com>2011-02-09 11:38:43 -0200
committerArnaldo Carvalho de Melo <acme@redhat.com>2011-02-16 14:47:55 -0200
commit5c35d69fb60b1dc49595f5b9a2c7158283e9eaf3 (patch)
treeb41206e03fa84bcbb752a320513feb8f7b7603ad /tools/perf/util/ui/helpline.c
parentperf: Optimize hrtimer events (diff)
perf ui: Serialize screen updates
The ui operations so far were used by just one thread, but 'perf top --tui' now has two threads updating the screen, so we need to use a mutex to avoid garbling the screen. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Tom Zanussi <tzanussi@gmail.com> LKML-Reference: <new-submission> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/ui/helpline.c')
1 files changed, 4 insertions, 1 deletions
diff --git a/tools/perf/util/ui/helpline.c b/tools/perf/util/ui/helpline.c
index 8d79daa4458a..f36d2ff509ed 100644
--- a/tools/perf/util/ui/helpline.c
+++ b/tools/perf/util/ui/helpline.c
@@ -5,6 +5,7 @@
#include "../debug.h"
#include "helpline.h"
+#include "ui.h"
void ui_helpline__pop(void)
@@ -55,7 +56,8 @@ int ui_helpline__show_help(const char *format, va_list ap)
int ret;
static int backlog;
- ret = vsnprintf(ui_helpline__last_msg + backlog,
+ pthread_mutex_lock(&ui__lock);
+ ret = vsnprintf(ui_helpline__last_msg + backlog,
sizeof(ui_helpline__last_msg) - backlog, format, ap);
backlog += ret;
@@ -64,6 +66,7 @@ int ui_helpline__show_help(const char *format, va_list ap)
backlog = 0;
+ pthread_mutex_unlock(&ui__lock);
return ret;