untangling do_lookup() - get rid of need_reval in !dentry case

Everything arriving into if (!dentry) will have need_reval = 1.
Indeed, the only way to get there with need_reval reset to 0 would
be via
	if (unlikely(d_need_lookup(dentry)))
		goto unlazy;
	if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE)) {
		status = d_revalidate(dentry, nd);
	if (unlikely(status <= 0)) {
		if (status != -ECHILD)
			need_reval = 0;
		goto unlazy;
...
unlazy:
	/* no assignments to dentry */
	if (dentry && unlikely(d_need_lookup(dentry))) {
		dput(dentry);
		dentry = NULL;
	}
and if d_need_lookup() had already been false the first time around, it
will remain false on the second call as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index 9ce43a3..14bb00a 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1181,7 +1181,6 @@ retry:
                                return PTR_ERR(dentry);
                        }
                        /* known good */
-                       need_reval = 0;
                        status = 1;
                } else if (unlikely(d_need_lookup(dentry))) {
                        dentry = d_inode_lookup(parent, dentry, nd);
@@ -1190,10 +1189,8 @@ retry:
                                return PTR_ERR(dentry);
                        }
                        /* known good */
-                       need_reval = 0;
                        status = 1;
-               }
-               if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE) && need_reval)
+               } else if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE))
                        status = d_revalidate(dentry, nd);
                if (unlikely(status <= 0)) {
                        if (status < 0) {
@@ -1209,7 +1206,6 @@ retry:
                                        return PTR_ERR(dentry);
                                }
                                /* known good */
-                               need_reval = 0;
                                status = 1;
                        }
                }
@@ -1226,7 +1222,6 @@ retry:
                if (!d_invalidate(dentry)) {
                        dput(dentry);
                        dentry = NULL;
-                       need_reval = 1;
                        goto retry;
                }
        }