diff options
| author | Steven Rostedt <rostedt@goodmis.org> | 2012-03-01 13:55:33 -0500 |
|---|---|---|
| committer | Clark Williams <williams@redhat.com> | 2012-03-24 09:29:28 -0500 |
| commit | 98e224500f4aaa842de765fc19234cae10085f8e (patch) | |
| tree | 626979ffd84f2a7ecdadf178ffa24b1dcf3ddeb4 | |
| parent | 0647eb91f22f0ebf5adcd792f7aa28195d42f016 (diff) | |
sched/rt: Fix wait_task_interactive() to test rt_spin_lock state
The wait_task_interactive() will have a task sleep waiting for another
task to have a certain state. But it ignores the rt_spin_locks state
and can return with an incorrect result if the task it is waiting
for is blocked on a rt_spin_lock() and is waking up.
The rt_spin_locks save the tasks state in the saved_state field
and the wait_task_interactive() must also test that state.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Carsten Emde <C.Emde@osadl.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Clark Williams <clark.williams@gmail.com>
Cc: stable-rt@vger.kernel.org
Link: http://lkml.kernel.org/r/20120301190345.979435764@goodmis.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/sched.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 81b340df601e..1cc706da3676 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2450,7 +2450,8 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) * is actually now running somewhere else! */ while (task_running(rq, p)) { - if (match_state && unlikely(p->state != match_state)) + if (match_state && unlikely(p->state != match_state) + && unlikely(p->saved_state != match_state)) return 0; cpu_relax(); } @@ -2465,7 +2466,8 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) running = task_running(rq, p); on_rq = p->on_rq; ncsw = 0; - if (!match_state || p->state == match_state) + if (!match_state || p->state == match_state + || p->saved_state == match_state) ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ task_rq_unlock(rq, p, &flags); |