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>

2 files changed, 2 insertions, 2 deletions

diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index d8f3a652243d..844a7903c72f 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -949,7 +949,7 @@ root_found:
                 table += 2;
         if (opt.check == 'r')
                 table++;
-        s->s_root->d_op = &isofs_dentry_ops[table];
+        d_set_d_op(s->s_root, &isofs_dentry_ops[table]);
 
         kfree(opt.iocharset);
 
diff --git a/fs/isofs/namei.c b/fs/isofs/namei.c
index 715f7d318046..679a849c3b27 100644
--- a/fs/isofs/namei.c
+++ b/fs/isofs/namei.c
@@ -172,7 +172,7 @@ struct dentry *isofs_lookup(struct inode *dir, struct dentry *dentry, struct nam
         struct inode *inode;
         struct page *page;
 
-        dentry->d_op = dir->i_sb->s_root->d_op;
+        d_set_d_op(dentry, dir->i_sb->s_root->d_op);
 
         page = alloc_page(GFP_USER);
         if (!page)