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author | Joonsoo Kim <iamjoonsoo.kim@lge.com> | 2014-08-07 01:04:35 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-07 03:01:14 +0200 |
commit | 367f7f2f45e7f601bcf87aeffb0c81e6d26e53df (patch) | |
tree | 9fd27e53d1e0c82e905ffd07501072d96f54d087 /mm/slab.c | |
parent | slab: destroy a slab without holding any alien cache lock (diff) | |
download | linux-367f7f2f45e7f601bcf87aeffb0c81e6d26e53df.tar.xz linux-367f7f2f45e7f601bcf87aeffb0c81e6d26e53df.zip |
slab: remove a useless lockdep annotation
Now, there is no code to hold two lock simultaneously, since we don't
call slab_destroy() with holding any lock. So, lockdep annotation is
useless now. Remove it.
v2: don't remove BAD_ALIEN_MAGIC in this patch. It will be removed
in the following patch.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/slab.c')
-rw-r--r-- | mm/slab.c | 153 |
1 files changed, 0 insertions, 153 deletions
diff --git a/mm/slab.c b/mm/slab.c index e4dc0896b891..630c85469164 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -472,139 +472,6 @@ static struct kmem_cache kmem_cache_boot = { #define BAD_ALIEN_MAGIC 0x01020304ul -#ifdef CONFIG_LOCKDEP - -/* - * Slab sometimes uses the kmalloc slabs to store the slab headers - * for other slabs "off slab". - * The locking for this is tricky in that it nests within the locks - * of all other slabs in a few places; to deal with this special - * locking we put on-slab caches into a separate lock-class. - * - * We set lock class for alien array caches which are up during init. - * The lock annotation will be lost if all cpus of a node goes down and - * then comes back up during hotplug - */ -static struct lock_class_key on_slab_l3_key; -static struct lock_class_key on_slab_alc_key; - -static struct lock_class_key debugobj_l3_key; -static struct lock_class_key debugobj_alc_key; - -static void slab_set_lock_classes(struct kmem_cache *cachep, - struct lock_class_key *l3_key, struct lock_class_key *alc_key, - struct kmem_cache_node *n) -{ - struct alien_cache **alc; - int r; - - lockdep_set_class(&n->list_lock, l3_key); - alc = n->alien; - /* - * FIXME: This check for BAD_ALIEN_MAGIC - * should go away when common slab code is taught to - * work even without alien caches. - * Currently, non NUMA code returns BAD_ALIEN_MAGIC - * for alloc_alien_cache, - */ - if (!alc || (unsigned long)alc == BAD_ALIEN_MAGIC) - return; - for_each_node(r) { - if (alc[r]) - lockdep_set_class(&(alc[r]->lock), alc_key); - } -} - -static void slab_set_debugobj_lock_classes_node(struct kmem_cache *cachep, - struct kmem_cache_node *n) -{ - slab_set_lock_classes(cachep, &debugobj_l3_key, &debugobj_alc_key, n); -} - -static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep) -{ - int node; - struct kmem_cache_node *n; - - for_each_kmem_cache_node(cachep, node, n) - slab_set_debugobj_lock_classes_node(cachep, n); -} - -static void init_node_lock_keys(int q) -{ - int i; - - if (slab_state < UP) - return; - - for (i = 1; i <= KMALLOC_SHIFT_HIGH; i++) { - struct kmem_cache_node *n; - struct kmem_cache *cache = kmalloc_caches[i]; - - if (!cache) - continue; - - n = get_node(cache, q); - if (!n || OFF_SLAB(cache)) - continue; - - slab_set_lock_classes(cache, &on_slab_l3_key, - &on_slab_alc_key, n); - } -} - -static void on_slab_lock_classes_node(struct kmem_cache *cachep, - struct kmem_cache_node *n) -{ - slab_set_lock_classes(cachep, &on_slab_l3_key, - &on_slab_alc_key, n); -} - -static inline void on_slab_lock_classes(struct kmem_cache *cachep) -{ - int node; - struct kmem_cache_node *n; - - VM_BUG_ON(OFF_SLAB(cachep)); - for_each_kmem_cache_node(cachep, node, n) - on_slab_lock_classes_node(cachep, n); -} - -static inline void __init init_lock_keys(void) -{ - int node; - - for_each_node(node) - init_node_lock_keys(node); -} -#else -static void __init init_node_lock_keys(int q) -{ -} - -static inline void init_lock_keys(void) -{ -} - -static inline void on_slab_lock_classes(struct kmem_cache *cachep) -{ -} - -static inline void on_slab_lock_classes_node(struct kmem_cache *cachep, - struct kmem_cache_node *n) -{ -} - -static void slab_set_debugobj_lock_classes_node(struct kmem_cache *cachep, - struct kmem_cache_node *n) -{ -} - -static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep) -{ -} -#endif - static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) @@ -1348,13 +1215,7 @@ static int cpuup_prepare(long cpu) spin_unlock_irq(&n->list_lock); kfree(shared); free_alien_cache(alien); - if (cachep->flags & SLAB_DEBUG_OBJECTS) - slab_set_debugobj_lock_classes_node(cachep, n); - else if (!OFF_SLAB(cachep) && - !(cachep->flags & SLAB_DESTROY_BY_RCU)) - on_slab_lock_classes_node(cachep, n); } - init_node_lock_keys(node); return 0; bad: @@ -1663,9 +1524,6 @@ void __init kmem_cache_init_late(void) BUG(); mutex_unlock(&slab_mutex); - /* Annotate slab for lockdep -- annotate the malloc caches */ - init_lock_keys(); - /* Done! */ slab_state = FULL; @@ -2446,17 +2304,6 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags) return err; } - if (flags & SLAB_DEBUG_OBJECTS) { - /* - * Would deadlock through slab_destroy()->call_rcu()-> - * debug_object_activate()->kmem_cache_alloc(). - */ - WARN_ON_ONCE(flags & SLAB_DESTROY_BY_RCU); - - slab_set_debugobj_lock_classes(cachep); - } else if (!OFF_SLAB(cachep) && !(flags & SLAB_DESTROY_BY_RCU)) - on_slab_lock_classes(cachep); - return 0; } |