Commit 39dc7bd9 authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
Browse files

btrfs: scrub: don't go ordered workqueue for dev-replace 



The workqueue fs_info->scrub_worker would go ordered workqueue if it's a
device replace operation.

However the scrub is relying on multiple workers to do data csum
verification, and we always submit several read requests in a row.

Thus there is no need to use ordered workqueue just for dev-replace.
We have extra synchronization (the main thread will always
submit-and-wait for dev-replace writes) to handle it for zoned devices.

Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent ae76d8e3

fs/btrfs/scrub.c

+3 −7
Original line number Diff line number Diff line
@@ -2777,8 +2777,7 @@ static void scrub_workers_put(struct btrfs_fs_info *fs_info) 
/*

 * get a reference count on fs_info->scrub_workers. start worker if necessary

 */

static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,

						int is_dev_replace)

static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info)

{

	struct workqueue_struct *scrub_workers = NULL;

	unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND;
@@ -2788,9 +2787,6 @@ static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info, 
	if (refcount_inc_not_zero(&fs_info->scrub_workers_refcnt))

		return 0;



	if (is_dev_replace)

		scrub_workers = alloc_ordered_workqueue("btrfs-scrub", flags);

	else

	scrub_workers = alloc_workqueue("btrfs-scrub", flags, max_active);

	if (!scrub_workers)

		return -ENOMEM;
@@ -2843,7 +2839,7 @@ int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start, 
	if (IS_ERR(sctx))

		return PTR_ERR(sctx);



	ret = scrub_workers_get(fs_info, is_dev_replace);

	ret = scrub_workers_get(fs_info);

	if (ret)

		goto out_free_ctx;