SLUB: Move sysfs operations outside of slub_lock
Sysfs can do a gazillion things when called. Make sure that we do not call
any sysfs functions while holding the slub_lock.
Just protect the essentials:
1. The list of all slab caches
2. The kmalloc_dma array
3. The ref counters of the slabs.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slub.c b/mm/slub.c
index f976d28..1c5d6a0 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2192,12 +2192,13 @@
s->refcount--;
if (!s->refcount) {
list_del(&s->list);
+ up_write(&slub_lock);
if (kmem_cache_close(s))
WARN_ON(1);
sysfs_slab_remove(s);
kfree(s);
- }
- up_write(&slub_lock);
+ } else
+ up_write(&slub_lock);
}
EXPORT_SYMBOL(kmem_cache_destroy);
@@ -2679,25 +2680,26 @@
*/
s->objsize = max(s->objsize, (int)size);
s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
+ up_write(&slub_lock);
if (sysfs_slab_alias(s, name))
goto err;
- } else {
- s = kmalloc(kmem_size, GFP_KERNEL);
- if (s && kmem_cache_open(s, GFP_KERNEL, name,
+ return s;
+ }
+ s = kmalloc(kmem_size, GFP_KERNEL);
+ if (s) {
+ if (kmem_cache_open(s, GFP_KERNEL, name,
size, align, flags, ctor)) {
- if (sysfs_slab_add(s)) {
- kfree(s);
- goto err;
- }
list_add(&s->list, &slab_caches);
- } else
- kfree(s);
+ up_write(&slub_lock);
+ if (sysfs_slab_add(s))
+ goto err;
+ return s;
+ }
+ kfree(s);
}
up_write(&slub_lock);
- return s;
err:
- up_write(&slub_lock);
if (flags & SLAB_PANIC)
panic("Cannot create slabcache %s\n", name);
else