Merge tag 'vfs-6.11.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs inode / dentry updates from Christian Brauner:
 "This contains smaller performance improvements to inodes and dentries:

  inode:

   - Add rcu based inode lookup variants.

     They avoid one inode hash lock acquire in the common case thereby
     significantly reducing contention. We already support RCU-based
     operations but didn't take advantage of them during inode
     insertion.

     Callers of iget_locked() get the improvement without any code
     changes. Callers that need a custom callback can switch to
     iget5_locked_rcu() as e.g., did btrfs.

     With 20 threads each walking a dedicated 1000 dirs * 1000 files
     directory tree to stat(2) on a 32 core + 24GB ram vm:

        before: 3.54s user 892.30s system 1966% cpu 45.549 total
        after:  3.28s user 738.66s system 1955% cpu 37.932 total (-16.7%)

     Long-term we should pick up the effort to introduce more
     fine-grained locking and possibly improve on the currently used
     hash implementation.

   - Start zeroing i_state in inode_init_always() instead of doing it in
     individual filesystems.

     This allows us to remove an unneeded lock acquire in new_inode()
     and not burden individual filesystems with this.

  dcache:

   - Move d_lockref out of the area used by RCU lookup to avoid
     cacheline ping poing because the embedded name is sharing a
     cacheline with d_lockref.

   - Fix dentry size on 32bit with CONFIG_SMP=y so it does actually end
     up with 128 bytes in total"

* tag 'vfs-6.11.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: fix dentry size
  vfs: move d_lockref out of the area used by RCU lookup
  bcachefs: remove now spurious i_state initialization
  xfs: remove now spurious i_state initialization in xfs_inode_alloc
  vfs: partially sanitize i_state zeroing on inode creation
  xfs: preserve i_state around inode_init_always in xfs_reinit_inode
  btrfs: use iget5_locked_rcu
  vfs: add rcu-based find_inode variants for iget ops

1 files changed, 3 insertions, 2 deletions

diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 9967334ea99f..cf629302d48e 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -86,9 +86,8 @@ xfs_inode_alloc(
 		return NULL;
 	}
 
-	/* VFS doesn't initialise i_mode or i_state! */
+	/* VFS doesn't initialise i_mode! */
 	VFS_I(ip)->i_mode = 0;
-	VFS_I(ip)->i_state = 0;
 	mapping_set_large_folios(VFS_I(ip)->i_mapping);
 
 	XFS_STATS_INC(mp, vn_active);
@@ -314,6 +313,7 @@ xfs_reinit_inode(
 	dev_t			dev = inode->i_rdev;
 	kuid_t			uid = inode->i_uid;
 	kgid_t			gid = inode->i_gid;
+	unsigned long		state = inode->i_state;
 
 	error = inode_init_always(mp->m_super, inode);
 
@@ -324,6 +324,7 @@ xfs_reinit_inode(
 	inode->i_rdev = dev;
 	inode->i_uid = uid;
 	inode->i_gid = gid;
+	inode->i_state = state;
 	mapping_set_large_folios(inode->i_mapping);
 	return error;
 }