[PATCH 6/6] clean up afterwards

[Al Viro]

a) dentry_kill() arguments are redundant - unlock_on_failure == !!morgue
b) the second kind of dentry_kill() can see dentry on process of being
killed only after it's been unlocked by dentry_iput(), so inode is
guaranteed to be NULL in that case
c) the first kind of dentry_kill can't see DCACHE_DENTRY_KILLED at all
(it's only set when refcount reaches zero and is unable to grow back;
the first kind is done right after having dropped the recount to zero).

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
 fs/dcache.c |   18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index f0773f6..a83b933 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -466,7 +466,7 @@ static DECLARE_WAIT_QUEUE_HEAD(free_wq);
  * Returns dentry requiring refcount drop, or NULL if we're done.
  */
 static struct dentry *
-dentry_kill(struct dentry *dentry, int unlock_on_failure, struct list_head *morgue)
+dentry_kill(struct dentry *dentry, struct list_head *morgue)
 	__releases(dentry->d_lock)
 {
 	struct inode *inode;
@@ -476,7 +476,7 @@ dentry_kill(struct dentry *dentry, int unlock_on_failure, struct list_head *morg
 	inode = dentry->d_inode;
 	if (inode && !spin_trylock(&inode->i_lock)) {
 relock:
-		if (unlock_on_failure) {
+		if (!morgue) {
 			spin_unlock(&dentry->d_lock);
 			cpu_relax();
 		}
@@ -492,12 +492,12 @@ relock:
 		goto relock;
 	}
 
-	if (unlikely(morgue && dentry->d_flags & DCACHE_DENTRY_KILLED)) {
+	if (unlikely(dentry->d_flags & DCACHE_DENTRY_KILLED)) {
+		/* morgue must be non-NULL */
 		list_move(&dentry->d_lru, morgue);
 		if (parent)
 			spin_unlock(&parent->d_lock);
-		if (inode)
-			spin_unlock(&inode->i_lock);
+		/* inode must be NULL */
 		spin_unlock(&dentry->d_lock);
 		return parent;
 	}
@@ -516,7 +516,7 @@ relock:
 	if (dentry->d_flags & DCACHE_LRU_LIST) {
 		if (!(dentry->d_flags & DCACHE_SHRINK_LIST))
 			d_lru_del(dentry);
-		else if (!unlock_on_failure)
+		else if (morgue)
 			d_shrink_del(dentry);
 		else
 			can_free = false;
@@ -605,7 +605,7 @@ repeat:
 	return;
 
 kill_it:
-	dentry = dentry_kill(dentry, 1, NULL);
+	dentry = dentry_kill(dentry, NULL);
 	if (dentry)
 		goto repeat;
 }
@@ -857,7 +857,7 @@ static void shrink_dentry_list(struct list_head *list)
 		}
 		rcu_read_unlock();
 
-		parent = dentry_kill(dentry, 0, &morgue);
+		parent = dentry_kill(dentry, &morgue);
 		/*
 		 * If dentry_kill returns NULL, we have nothing more to do.
 		 */
@@ -884,7 +884,7 @@ static void shrink_dentry_list(struct list_head *list)
 		 */
 		dentry = parent;
 		while (dentry && !lockref_put_or_lock(&dentry->d_lockref))
-			dentry = dentry_kill(dentry, 1, NULL);
+			dentry = dentry_kill(dentry, NULL);
 		rcu_read_lock();
 	}
 	rcu_read_unlock();
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/