[v2,6/8] btrfs: remove unnecessary delayed refs locking at btrfs_qgroup_trace_extent()

Commit Message

Filipe Manana Sept. 26, 2024, 9:33 a.m. UTC

From: Filipe Manana <[e-mail]>

There's no need to hold the delayed refs spinlock when calling
btrfs_qgroup_trace_extent_nolock() from btrfs_qgroup_trace_extent(), since
it doesn't change anything in delayed refs and it only changes the xarray
used to track qgroup extent records, which is protected by the xarray's
lock.

Holding the lock is only adding unnecessary lock contention with other
tasks that actually need to take the lock to add/remove/change delayed
references. So remove the locking.

Signed-off-by: Filipe Manana <[e-mail]>
---
 fs/btrfs/qgroup.c | 3 ---
 1 file changed, 3 deletions(-)

Patch

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 8d000a9d35af..3574af6d25ef 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2021,7 +2021,6 @@  int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
 	}
 #endif
 
-	lockdep_assert_held(&delayed_refs->lock);
 	trace_btrfs_qgroup_trace_extent(fs_info, record, bytenr);
 
 	xa_lock(&delayed_refs->dirty_extents);
@@ -2160,9 +2159,7 @@  int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
 	record->num_bytes = num_bytes;
 	record->old_roots = NULL;
 
-	spin_lock(&delayed_refs->lock);
 	ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record, bytenr);
-	spin_unlock(&delayed_refs->lock);
 	if (ret) {
 		/* Clean up if insertion fails or item exists. */
 		xa_release(&delayed_refs->dirty_extents, index);