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author | Xunlei Pang <xlpang@redhat.com> | 2017-03-23 15:56:09 +0100 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2017-04-04 11:44:05 +0200 |
commit | 85e2d4f992868ad78dc8bb2c077b652fcfb3661a (patch) | |
tree | b0c81f1685b1799f174bfe8ba0a914dd3f500f18 | |
parent | e96a7705e7d3fef96aec9b590c63b2f6f7d2ba22 (diff) | |
download | linux-85e2d4f992868ad78dc8bb2c077b652fcfb3661a.tar.bz2 |
sched/deadline/rtmutex: Dont miss the dl_runtime/dl_period update
Currently dl tasks will actually return at the very beginning
of rt_mutex_adjust_prio_chain() in !detect_deadlock cases:
if (waiter->prio == task->prio) {
if (!detect_deadlock)
goto out_unlock_pi; // out here
else
requeue = false;
}
As the deadline value of blocked deadline tasks(waiters) without
changing their sched_class(thus prio doesn't change) never changes,
this seems reasonable, but it actually misses the chance of updating
rt_mutex_waiter's "dl_runtime(period)_copy" if a waiter updates its
deadline parameters(dl_runtime, dl_period) or boosted waiter changes
to !deadline class.
Thus, force deadline task not out by adding the !dl_prio() condition.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@arm.com
Cc: bigeasy@linutronix.de
Cc: mathieu.desnoyers@efficios.com
Cc: jdesfossez@efficios.com
Cc: bristot@redhat.com
Link: http://lkml.kernel.org/r/1460633827-345-7-git-send-email-xlpang@redhat.com
Link: http://lkml.kernel.org/r/20170323150216.206577901@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r-- | kernel/locking/rtmutex.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index bc05b104eaed..8faf472c430f 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -605,7 +605,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, * enabled we continue, but stop the requeueing in the chain * walk. */ - if (waiter->prio == task->prio) { + if (waiter->prio == task->prio && !dl_task(task)) { if (!detect_deadlock) goto out_unlock_pi; else |