diff options
| author | Steven Rostedt <rostedt@goodmis.org> | 2012-03-01 13:55:33 -0500 |
|---|---|---|
| committer | Steven Rostedt <rostedt@rostedt.homelinux.com> | 2012-10-26 14:42:45 -0400 |
| commit | 0f194bf75cb462cc7bd77b1660c1e1915690ae7c (patch) | |
| tree | 7d515818c167853bf503f81a1df1d7d7a4de2127 | |
| parent | a77cae5230538c575ab23ddaaa8d3e749515b032 (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 9a43d00c8ea6..ae081012cd9c 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2281,7 +2281,8 @@ 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(); } @@ -2296,7 +2297,8 @@ 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); |