btrfs: scrub: convert scrub_workers_refcnt to refcount_t

Use the refcount_t for fs_info::scrub_workers_refcnt instead of int so
we get the extra checks. All reference changes are still done under
scrub_lock.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Anand Jain
2019-01-30 14:45:02 +08:00
committed by David Sterba
parent eb4318e59a
commit ff09c4ca59
3 changed files with 8 additions and 5 deletions

View File

@@ -3743,7 +3743,7 @@ static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
lockdep_assert_held(&fs_info->scrub_lock);
if (fs_info->scrub_workers_refcnt == 0) {
if (refcount_read(&fs_info->scrub_workers_refcnt) == 0) {
fs_info->scrub_workers = btrfs_alloc_workqueue(fs_info, "scrub",
flags, is_dev_replace ? 1 : max_active, 4);
if (!fs_info->scrub_workers)
@@ -3760,8 +3760,11 @@ static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
max_active, 2);
if (!fs_info->scrub_parity_workers)
goto fail_scrub_parity_workers;
refcount_set(&fs_info->scrub_workers_refcnt, 1);
} else {
refcount_inc(&fs_info->scrub_workers_refcnt);
}
++fs_info->scrub_workers_refcnt;
return 0;
fail_scrub_parity_workers:
@@ -3927,7 +3930,7 @@ int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
mutex_lock(&fs_info->scrub_lock);
dev->scrub_ctx = NULL;
if (--fs_info->scrub_workers_refcnt == 0) {
if (refcount_dec_and_test(&fs_info->scrub_workers_refcnt)) {
scrub_workers = fs_info->scrub_workers;
scrub_wr_comp = fs_info->scrub_wr_completion_workers;
scrub_parity = fs_info->scrub_parity_workers;