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>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 998e3a715bcc..35efd85a4d32 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -120,7 +120,7 @@ static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry,
                 goto out;
 
         err = NULL;
-        dentry->d_op = &proc_sys_dentry_operations;
+        d_set_d_op(dentry, &proc_sys_dentry_operations);
         d_add(dentry, inode);
 
 out:
@@ -201,7 +201,7 @@ static int proc_sys_fill_cache(struct file *filp, void *dirent,
                                 dput(child);
                                 return -ENOMEM;
                         } else {
-                                child->d_op = &proc_sys_dentry_operations;
+                                d_set_d_op(child, &proc_sys_dentry_operations);
                                 d_add(child, inode);
                         }
                 } else {