Btrfs: fix race in worker_loop
Need to check kthread_should_stop after schedule_timeout() before calling
schedule(). This causes threads to sleep with potentially no one to wake them
up causing mount(2) to hang in btrfs_stop_workers waiting for threads to stop.
Signed-off-by: Amit Gud <gud@ksu.edu>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index c84ca1f..cba701d 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -195,6 +195,9 @@
if (!list_empty(&worker->pending))
continue;
+ if (kthread_should_stop())
+ break;
+
/* still no more work?, sleep for real */
spin_lock_irq(&worker->lock);
set_current_state(TASK_INTERRUPTIBLE);
@@ -208,7 +211,8 @@
worker->working = 0;
spin_unlock_irq(&worker->lock);
- schedule();
+ if (!kthread_should_stop())
+ schedule();
}
__set_current_state(TASK_RUNNING);
}