Unverified Commit 3e18f625 authored by Mateusz Guzik's avatar Mateusz Guzik Committed by Christian Brauner
Browse files

btrfs: utilize IOP_FASTPERM_MAY_EXEC 



Root filesystem was ext4, btrfs was mounted on /testfs.

Then issuing access(2) in a loop on /testfs/repos/linux/include/linux/fs.h
on Sapphire Rapids (ops/s):

before: 3447976
after:	3620879 (+5%)

Signed-off-by: default avatarMateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251107142149.989998-3-mjguzik@gmail.com


Acked-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent e631df89

fs/btrfs/inode.c

+11 −1
Original line number Diff line number Diff line
@@ -5837,6 +5837,8 @@ struct btrfs_inode *btrfs_iget(u64 ino, struct btrfs_root *root) 
	if (ret)

		return ERR_PTR(ret);



	if (S_ISDIR(inode->vfs_inode.i_mode))

		inode->vfs_inode.i_opflags |= IOP_FASTPERM_MAY_EXEC;

	unlock_new_inode(&inode->vfs_inode);

	return inode;

}
@@ -6788,8 +6790,11 @@ static int btrfs_create_common(struct inode *dir, struct dentry *dentry, 
	}



	ret = btrfs_create_new_inode(trans, &new_inode_args);

	if (!ret)

	if (!ret) {

		if (S_ISDIR(inode->i_mode))

			inode->i_opflags |= IOP_FASTPERM_MAY_EXEC;

		d_instantiate_new(dentry, inode);

	}



	btrfs_end_transaction(trans);

	btrfs_btree_balance_dirty(fs_info);
@@ -9169,6 +9174,11 @@ int btrfs_prealloc_file_range_trans(struct inode *inode, 
					   min_size, actual_len, alloc_hint, trans);

}



/*

 * NOTE: in case you are adding MAY_EXEC check for directories:

 * we are marking them with IOP_FASTPERM_MAY_EXEC, allowing path lookup to

 * elide calls here.

 */

static int btrfs_permission(struct mnt_idmap *idmap,

			    struct inode *inode, int mask)

{