From 809c104221fc2a33b5809ef1806640d6686c823e Mon Sep 17 00:00:00 2001 From: Mike Galbraith Date: Fri, 26 Mar 2010 11:11:33 +0100 Subject: [PATCH] --- yaml --- r: 189431 b: refs/heads/master c: 8bb39f9aa068262732fe44b965d7a6eb5a5a7d67 h: refs/heads/master i: 189429: b85731d30152f912f8ddbe533f07fa032a75c6a8 189427: a501001aca03c3b3e2218caa00203327cccc80b5 189423: 18a714cdf478e6d3514fa3357e1c52c7910ec873 v: v3 --- [refs] | 2 +- trunk/kernel/perf_event.c | 15 ++++++++++++--- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/[refs] b/[refs] index 62b381b1b2e5..dab065d2cafb 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: 257ef9d21f1b008a6c7425544b36641c4325a922 +refs/heads/master: 8bb39f9aa068262732fe44b965d7a6eb5a5a7d67 diff --git a/trunk/kernel/perf_event.c b/trunk/kernel/perf_event.c index b0feb4795af3..96aae13c7960 100644 --- a/trunk/kernel/perf_event.c +++ b/trunk/kernel/perf_event.c @@ -3376,15 +3376,23 @@ static void perf_event_task_output(struct perf_event *event, struct perf_task_event *task_event) { struct perf_output_handle handle; - int size; struct task_struct *task = task_event->task; - int ret; + unsigned long flags; + int size, ret; + + /* + * If this CPU attempts to acquire an rq lock held by a CPU spinning + * in perf_output_lock() from interrupt context, it's game over. + */ + local_irq_save(flags); size = task_event->event_id.header.size; ret = perf_output_begin(&handle, event, size, 0, 0); - if (ret) + if (ret) { + local_irq_restore(flags); return; + } task_event->event_id.pid = perf_event_pid(event, task); task_event->event_id.ppid = perf_event_pid(event, current); @@ -3395,6 +3403,7 @@ static void perf_event_task_output(struct perf_event *event, perf_output_put(&handle, task_event->event_id); perf_output_end(&handle); + local_irq_restore(flags); } static int perf_event_task_match(struct perf_event *event)