[PATCH 1/2] btrfs: cleaner_kthread() doesn't need explicit freeze

From: Jiri Kosina
Date: Tue Mar 15 2016 - 16:48:20 EST


cleaner_kthread() is not marked freezable, and therefore calling
try_to_freeze() in its context is a pointless no-op.

In addition to that, as has been clearly demonstrated by 80ad623edd2d
("Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()"), it's perfectly
valid / legal for cleaner_kthread() to stay scheduled out in an arbitrary
place during suspend (in that particular example that was waiting for
reading of extent pages), so there is no need to leave any traces of
freezer in this kthread.

Fixes: 80ad623edd2d ("Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()")
Fixes: 696249132158 ("btrfs: clear PF_NOFREEZE in cleaner_kthread()")
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
---
fs/btrfs/disk-io.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4545e2e..d8d68af 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1830,7 +1830,7 @@ static int cleaner_kthread(void *arg)
*/
btrfs_delete_unused_bgs(root->fs_info);
sleep:
- if (!try_to_freeze() && !again) {
+ if (!again) {
set_current_state(TASK_INTERRUPTIBLE);
if (!kthread_should_stop())
schedule();
--
Jiri Kosina
SUSE Labs