fs: dcache reduce branches in lookup path

Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
This commit is contained in:
Nick Piggin 2011-01-07 17:49:55 +11:00
parent 5f57cbcc02
commit fb045adb99
63 changed files with 174 additions and 137 deletions

View file

@ -189,7 +189,7 @@ int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry,
if (special_file(lower_inode->i_mode))
init_special_inode(inode, lower_inode->i_mode,
lower_inode->i_rdev);
dentry->d_op = &ecryptfs_dops;
d_set_d_op(dentry, &ecryptfs_dops);
fsstack_copy_attr_all(inode, lower_inode);
/* This size will be overwritten for real files w/ headers and
* other metadata */
@ -594,7 +594,7 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
deactivate_locked_super(s);
goto out;
}
s->s_root->d_op = &ecryptfs_dops;
d_set_d_op(s->s_root, &ecryptfs_dops);
s->s_root->d_sb = s;
s->s_root->d_parent = s->s_root;