freezer: unexport refrigerator() and update try_to_freeze() slightly
There is no reason to export two functions for entering the
refrigerator. Calling refrigerator() instead of try_to_freeze()
doesn't save anything noticeable or removes any race condition.
* Rename refrigerator() to __refrigerator() and make it return bool
indicating whether it scheduled out for freezing.
* Update try_to_freeze() to return bool and relay the return value of
__refrigerator() if freezing().
* Convert all refrigerator() users to try_to_freeze().
* Update documentation accordingly.
* While at it, add might_sleep() to try_to_freeze().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Christoph Hellwig <hch@infradead.org>
diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 7ec1409..98ab240 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -340,7 +340,7 @@
if (freezing(current)) {
worker->working = 0;
spin_unlock_irq(&worker->lock);
- refrigerator();
+ try_to_freeze();
} else {
spin_unlock_irq(&worker->lock);
if (!kthread_should_stop()) {