slab: delete cache from list after __kmem_cache_shutdown succeeds

Currently, on kmem_cache_destroy we delete the cache from the slab_list
before __kmem_cache_shutdown, inserting it back to the list on failure.
Initially, this was done, because we could release the slab_mutex in
__kmem_cache_shutdown to delete sysfs slub entry, but since commit
41a212859a ("slub: use sysfs'es release mechanism for kmem_cache") we
remove sysfs entry later in kmem_cache_destroy after dropping the
slab_mutex, so that no implementation of __kmem_cache_shutdown can ever
release the lock.  Therefore we can simplify the code a bit by moving
list_del after __kmem_cache_shutdown.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Vladimir Davydov 2014-06-04 16:10:03 -07:00 committed by Linus Torvalds
parent 776ed0f037
commit 0bd62b1190

View File

@ -346,15 +346,15 @@ void kmem_cache_destroy(struct kmem_cache *s)
if (memcg_cleanup_cache_params(s) != 0)
goto out_unlock;
list_del(&s->list);
if (__kmem_cache_shutdown(s) != 0) {
list_add(&s->list, &slab_caches);
printk(KERN_ERR "kmem_cache_destroy %s: "
"Slab cache still has objects\n", s->name);
dump_stack();
goto out_unlock;
}
list_del(&s->list);
mutex_unlock(&slab_mutex);
if (s->flags & SLAB_DESTROY_BY_RCU)
rcu_barrier();