From ea382199071931d19aac5f688b543e07360e2b64 Mon Sep 17 00:00:00 2001 From: Mateusz Guzik Date: Wed, 20 Nov 2024 12:20:34 +0100 Subject: vfs: support caching symlink lengths in inodes When utilized it dodges strlen() in vfs_readlink(), giving about 1.5% speed up when issuing readlink on /initrd.img on ext4. Filesystems opt in by calling inode_set_cached_link() when creating an inode. The size is stored in a new union utilizing the same space as i_devices, thus avoiding growing the struct or taking up any more space. Churn-wise the current readlink_copy() helper is patched to accept the size instead of calculating it. Signed-off-by: Mateusz Guzik Link: https://lore.kernel.org/r/20241120112037.822078-2-mjguzik@gmail.com Signed-off-by: Christian Brauner --- security/apparmor/apparmorfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'security') diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 2c0185ebc900..c07d150685d7 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -2612,7 +2612,7 @@ static int policy_readlink(struct dentry *dentry, char __user *buffer, res = snprintf(name, sizeof(name), "%s:[%lu]", AAFS_NAME, d_inode(dentry)->i_ino); if (res > 0 && res < sizeof(name)) - res = readlink_copy(buffer, buflen, name); + res = readlink_copy(buffer, buflen, name, strlen(name)); else res = -ENOENT; -- cgit v1.2.3