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

@@ -25,7 +25,7 @@ static struct dentry *hfs_lookup(struct inode *dir, struct dentry *dentry,
struct inode *inode = NULL;
int res;
dentry->d_op = &hfs_dentry_operations;
d_set_d_op(dentry, &hfs_dentry_operations);
hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
hfs_cat_build_key(dir->i_sb, fd.search_key, dir->i_ino, &dentry->d_name);

View File

@@ -434,7 +434,7 @@ static int hfs_fill_super(struct super_block *sb, void *data, int silent)
if (!sb->s_root)
goto bail_iput;
sb->s_root->d_op = &hfs_dentry_operations;
d_set_d_op(sb->s_root, &hfs_dentry_operations);
/* everything's okay */
return 0;