Commit 45bac0f3 authored by Liu Bo's avatar Liu Bo Committed by David Sterba
Browse files

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: default avatarLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 69cc7151

fs/btrfs/ioctl.c

+3 −18
Original line number Diff line number Diff line
@@ -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)