Commit a3f7fde2 authored by Zhao Lei's avatar Zhao Lei Committed by David Sterba
Browse files

btrfs: reada: Move is_need_to_readahead contition earlier 



Move is_need_to_readahead contition earlier to avoid useless loop
to get relative data for readahead.

Signed-off-by: default avatarZhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 97d5f0e6

fs/btrfs/reada.c

+9 −11
Original line number Diff line number Diff line
@@ -660,7 +660,6 @@ static int reada_start_machine_dev(struct btrfs_fs_info *fs_info, 
	u64 logical;

	int ret;

	int i;

	int need_kick = 0;



	spin_lock(&fs_info->reada_lock);

	if (dev->reada_curr_zone == NULL) {
@@ -696,6 +695,15 @@ static int reada_start_machine_dev(struct btrfs_fs_info *fs_info, 


	spin_unlock(&fs_info->reada_lock);



	spin_lock(&re->lock);

	if (re->scheduled_for || list_empty(&re->extctl)) {

		spin_unlock(&re->lock);

		reada_extent_put(fs_info, re);

		return 0;

	}

	re->scheduled_for = dev;

	spin_unlock(&re->lock);



	/*

	 * find mirror num

	 */
@@ -707,18 +715,8 @@ static int reada_start_machine_dev(struct btrfs_fs_info *fs_info, 
	}

	logical = re->logical;



	spin_lock(&re->lock);

	if (!re->scheduled_for && !list_empty(&re->extctl)) {

		re->scheduled_for = dev;

		need_kick = 1;

	}

	spin_unlock(&re->lock);



	reada_extent_put(fs_info, re);



	if (!need_kick)

		return 0;



	atomic_inc(&dev->reada_in_flight);

	ret = reada_tree_block_flagged(fs_info->extent_root, logical,

			mirror_num, &eb);