make retain_dentry() neutral with respect to refcounting

retain_dentry() used to decrement refcount if and only if it returned
true.  Lift those decrements into the callers.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/dcache.c b/fs/dcache.c
index 0718b3895c129532a69e21f8febba19e59682b0c..2e74f3f2ce2ee03752b314ae4514f4f1a44649e6 100644 (file)
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -680,7 +680,6 @@ static inline bool retain_dentry(struct dentry *dentry)
                return false;
 
        /* retain; LRU fodder */
-       dentry->d_lockref.count--;
        if (unlikely(!(dentry->d_flags & DCACHE_LRU_LIST)))
                d_lru_add(dentry);
        else if (unlikely(!(dentry->d_flags & DCACHE_REFERENCED)))
@@ -744,6 +743,8 @@ got_locks:
        } else if (likely(!retain_dentry(dentry))) {
                __dentry_kill(dentry);
                return parent;
+       } else {
+               dentry->d_lockref.count--;
        }
        /* we are keeping it, after all */
        if (inode)
@@ -893,6 +894,7 @@ void dput(struct dentry *dentry)
                rcu_read_unlock();
 
                if (likely(retain_dentry(dentry))) {
+                       dentry->d_lockref.count--;
                        spin_unlock(&dentry->d_lock);
                        return;
                }
@@ -925,6 +927,8 @@ void dput_to_list(struct dentry *dentry, struct list_head *list)
        if (!retain_dentry(dentry)) {
                --dentry->d_lockref.count;
                to_shrink_list(dentry, list);
+       } else {
+               --dentry->d_lockref.count;
        }
        spin_unlock(&dentry->d_lock);
 }