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>
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 3b3e072..35ffe43 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -227,10 +227,10 @@
}
out:
unlock_super(sb);
- dentry->d_op = &msdos_dentry_operations;
+ d_set_d_op(dentry, &msdos_dentry_operations);
dentry = d_splice_alias(inode, dentry);
if (dentry)
- dentry->d_op = &msdos_dentry_operations;
+ d_set_d_op(dentry, &msdos_dentry_operations);
return dentry;
error:
@@ -673,7 +673,7 @@
}
sb->s_flags |= MS_NOATIME;
- sb->s_root->d_op = &msdos_dentry_operations;
+ d_set_d_op(sb->s_root, &msdos_dentry_operations);
unlock_super(sb);
return 0;
}