[PATCH 02/32] xfs: check the flags earlier in xfs_attr_match

Darrick J. Wong
2024-04-10T00:54:02Z

From: Christoph Hellwig <hch@lst.de>

Checking the flags match is much cheaper than a memcmp, so do it early
on in xfs_attr_match, and also add a little helper to calculate the
match mask right under the comment explaining the logic for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/libxfs/xfs_attr_leaf.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 53ef784e3049e..9cb3a5d1c07d1 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -506,6 +506,13 @@ xfs_attr3_leaf_read(
* INCOMPLETE flag will not be set in attr->attr_filter, but rather
* XFS_DA_OP_RECOVERY will be set in args->op_flags.
*/
+static inline unsigned int xfs_attr_match_mask(const struct xfs_da_args *args)
+{
+ if (args->op_flags & XFS_DA_OP_RECOVERY)
+ return XFS_ATTR_NSP_ONDISK_MASK;
+ return XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE;
+}
+
static bool
xfs_attr_match(
struct xfs_da_args *args,
@@ -513,21 +520,15 @@ xfs_attr_match(
const unsigned char *name,
unsigned int namelen)
{
+ unsigned int mask = xfs_attr_match_mask(args);

if (args->namelen != namelen)
return false;
+ if ((args->attr_filter & mask) != (attr_flags & mask))
+ return false;
if (memcmp(args->name, name, namelen) != 0)
return false;

- /* Recovery ignores the INCOMPLETE flag. */
- if ((args->op_flags & XFS_DA_OP_RECOVERY) &&
- args->attr_filter == (attr_flags & XFS_ATTR_NSP_ONDISK_MASK))
- return true;
-
- /* All remaining matches need to be filtered by INCOMPLETE state. */
- if (args->attr_filter !=
- (attr_flags & (XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE)))
- return false;
return true;
}