Btrfs: use wait_event instead of a single function
Since TASK_UNINTERRUPTIBLE has been used here, wait_event() can do the
same job.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 1d4f8a7..95bd533 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -609,23 +609,6 @@ static noinline int create_subvol(struct inode *dir,
return ret;
}
-static void btrfs_wait_for_no_snapshotting_writes(struct btrfs_root *root)
-{
- s64 writers;
- DEFINE_WAIT(wait);
-
- do {
- prepare_to_wait(&root->subv_writers->wait, &wait,
- TASK_UNINTERRUPTIBLE);
-
- writers = percpu_counter_sum(&root->subv_writers->counter);
- if (writers)
- schedule();
-
- } while (writers);
- finish_wait(&root->subv_writers->wait, &wait);
-}
-
static int create_snapshot(struct btrfs_root *root, struct inode *dir,
struct dentry *dentry,
u64 *async_transid, bool readonly,
@@ -654,7 +637,9 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
atomic_inc(&root->will_be_snapshotted);
smp_mb__after_atomic();
- btrfs_wait_for_no_snapshotting_writes(root);
+ /* wait for no snapshot writes */
+ wait_event(root->subv_writers->wait,
+ percpu_counter_sum(&root->subv_writers->counter) == 0);
ret = btrfs_start_delalloc_inodes(root, 0);
if (ret)