btrfs: use mutex in btrfs_resume_balance_async
While the spinlock does not cause problems, using the mutex is more
correct and consistent with others. The global status of balance is eg.
checked from btrfs_pause_balance or btrfs_cancel_balance with mutex.
Resuming balance happens during mount or ro->rw remount. In the former
case, no other user of the balance_ctl exists, in the latter, balance
cannot run until the ro/rw transition is finished.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 197b91b..447a0c2 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3959,12 +3959,12 @@ int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
{
struct task_struct *tsk;
- spin_lock(&fs_info->balance_lock);
+ mutex_lock(&fs_info->balance_mutex);
if (!fs_info->balance_ctl) {
- spin_unlock(&fs_info->balance_lock);
+ mutex_unlock(&fs_info->balance_mutex);
return 0;
}
- spin_unlock(&fs_info->balance_lock);
+ mutex_unlock(&fs_info->balance_mutex);
if (btrfs_test_opt(fs_info, SKIP_BALANCE)) {
btrfs_info(fs_info, "force skipping balance");