@@ -739,14 +739,10 @@ static struct dentry *dentry_kill(struct dentry *dentry)
spin_lock(&dentry->d_lock);
parent = lock_parent(dentry);
got_locks:
- if (unlikely(dentry->d_lockref.count != 1)) {
- dentry->d_lockref.count--;
- } else if (likely(!retain_dentry(dentry))) {
- dentry->d_lockref.count--;
+ dentry->d_lockref.count--;
+ if (likely(dentry->d_lockref.count == 0)) {
__dentry_kill(dentry);
return parent;
- } else {
- dentry->d_lockref.count--;
}
/* we are keeping it, after all */
if (inode)
We have already checked it and dentry used to look not worthy of keeping. The only hard obstacle to evicting dentry is non-zero refcount; everything else is advisory - e.g. memory pressure could evict any dentry found with refcount zero. On the slow path in dentry_kill() we had dropped and regained ->d_lock; we must recheck the refcount, but everything else is not worth bothering with. Note that filesystem can not count upon ->d_delete() being called for dentry - not even once. Again, memory pressure (as well as d_prune_aliases(), or attempted rmdir() of ancestor, or...) will not call ->d_delete() at all. So from the correctness point of view we are fine doing the check only once. And it makes things simpler down the road. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> --- fs/dcache.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)