static void free_block(struct kmem_cache *cachep, void **objpp, int len,
int node);
static int enable_cpucache(struct kmem_cache *cachep);
-static void cache_reap(void *unused);
+static void cache_reap(struct work_struct *unused);
/*
* This function must be completely optimized away if a constant is passed to
}
#endif
-/* Guard access to the cache-chain. */
+/*
+ * 1. Guard access to the cache-chain.
+ * 2. Protect sanity of cpu_online_map against cpu hotplug events
+ */
static DEFINE_MUTEX(cache_chain_mutex);
static struct list_head cache_chain;
return g_cpucache_up == FULL;
}
-static DEFINE_PER_CPU(struct work_struct, reap_work);
+static DEFINE_PER_CPU(struct delayed_work, reap_work);
static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep)
{
dump_stack();
}
+/*
+ * By default on NUMA we use alien caches to stage the freeing of
+ * objects allocated from other nodes. This causes massive memory
+ * inefficiencies when using fake NUMA setup to split memory into a
+ * large number of small nodes, so it can be disabled on the command
+ * line
+ */
+
+static int use_alien_caches __read_mostly = 1;
+static int __init noaliencache_setup(char *s)
+{
+ use_alien_caches = 0;
+ return 1;
+}
+__setup("noaliencache", noaliencache_setup);
+
#ifdef CONFIG_NUMA
/*
* Special reaping functions for NUMA systems called from cache_reap().
if (node == MAX_NUMNODES)
node = first_node(node_online_map);
- __get_cpu_var(reap_node) = node;
+ per_cpu(reap_node, cpu) = node;
}
static void next_reap_node(void)
*/
static void __devinit start_cpu_timer(int cpu)
{
- struct work_struct *reap_work = &per_cpu(reap_work, cpu);
+ struct delayed_work *reap_work = &per_cpu(reap_work, cpu);
/*
* When this gets called from do_initcalls via cpucache_init(),
* init_workqueues() has already run, so keventd will be setup
* at that time.
*/
- if (keventd_up() && reap_work->func == NULL) {
+ if (keventd_up() && reap_work->work.func == NULL) {
init_reap_node(cpu);
- INIT_WORK(reap_work, cache_reap, NULL);
+ INIT_DELAYED_WORK(reap_work, cache_reap);
schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu);
}
}
* Make sure we are not freeing a object from another node to the array
* cache on this cpu.
*/
- if (likely(slabp->nodeid == node))
+ if (likely(slabp->nodeid == node) || unlikely(!use_alien_caches))
return 0;
l3 = cachep->nodelists[node];
list_for_each_entry(cachep, &cache_chain, next) {
struct array_cache *nc;
struct array_cache *shared;
- struct array_cache **alien;
+ struct array_cache **alien = NULL;
nc = alloc_arraycache(node, cachep->limit,
cachep->batchcount);
if (!shared)
goto bad;
- alien = alloc_alien_cache(node, cachep->limit);
- if (!alien)
- goto bad;
+ if (use_alien_caches) {
+ alien = alloc_alien_cache(node, cachep->limit);
+ if (!alien)
+ goto bad;
+ }
cachep->array[cpu] = nc;
l3 = cachep->nodelists[node];
BUG_ON(!l3);
kfree(shared);
free_alien_cache(alien);
}
- mutex_unlock(&cache_chain_mutex);
break;
case CPU_ONLINE:
+ mutex_unlock(&cache_chain_mutex);
start_cpu_timer(cpu);
break;
#ifdef CONFIG_HOTPLUG_CPU
+ case CPU_DOWN_PREPARE:
+ mutex_lock(&cache_chain_mutex);
+ break;
+ case CPU_DOWN_FAILED:
+ mutex_unlock(&cache_chain_mutex);
+ break;
case CPU_DEAD:
/*
* Even if all the cpus of a node are down, we don't free the
* gets destroyed at kmem_cache_destroy().
*/
/* fall thru */
+#endif
case CPU_UP_CANCELED:
- mutex_lock(&cache_chain_mutex);
list_for_each_entry(cachep, &cache_chain, next) {
struct array_cache *nc;
struct array_cache *shared;
}
mutex_unlock(&cache_chain_mutex);
break;
-#endif
}
return NOTIFY_OK;
bad:
- mutex_unlock(&cache_chain_mutex);
return NOTIFY_BAD;
}
}
/*
- * Prevent CPUs from coming and going.
- * lock_cpu_hotplug() nests outside cache_chain_mutex
+ * We use cache_chain_mutex to ensure a consistent view of
+ * cpu_online_map as well. Please see cpuup_callback
*/
- lock_cpu_hotplug();
-
mutex_lock(&cache_chain_mutex);
list_for_each_entry(pc, &cache_chain, next) {
if (flags & SLAB_RED_ZONE || flags & SLAB_STORE_USER)
ralign = BYTES_PER_WORD;
- /* 2) arch mandated alignment: disables debug if necessary */
+ /* 2) arch mandated alignment */
if (ralign < ARCH_SLAB_MINALIGN) {
ralign = ARCH_SLAB_MINALIGN;
- if (ralign > BYTES_PER_WORD)
- flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
}
- /* 3) caller mandated alignment: disables debug if necessary */
+ /* 3) caller mandated alignment */
if (ralign < align) {
ralign = align;
- if (ralign > BYTES_PER_WORD)
- flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
}
+ /* disable debug if necessary */
+ if (ralign > BYTES_PER_WORD)
+ flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
/*
* 4) Store it.
*/
panic("kmem_cache_create(): failed to create slab `%s'\n",
name);
mutex_unlock(&cache_chain_mutex);
- unlock_cpu_hotplug();
return cachep;
}
EXPORT_SYMBOL(kmem_cache_create);
return nr_freed;
}
+/* Called with cache_chain_mutex held to protect against cpu hotplug */
static int __cache_shrink(struct kmem_cache *cachep)
{
int ret = 0, i = 0;
*/
int kmem_cache_shrink(struct kmem_cache *cachep)
{
+ int ret;
BUG_ON(!cachep || in_interrupt());
- return __cache_shrink(cachep);
+ mutex_lock(&cache_chain_mutex);
+ ret = __cache_shrink(cachep);
+ mutex_unlock(&cache_chain_mutex);
+ return ret;
}
EXPORT_SYMBOL(kmem_cache_shrink);
{
BUG_ON(!cachep || in_interrupt());
- /* Don't let CPUs to come and go */
- lock_cpu_hotplug();
-
/* Find the cache in the chain of caches. */
mutex_lock(&cache_chain_mutex);
/*
* the chain is never empty, cache_cache is never destroyed
*/
list_del(&cachep->next);
- mutex_unlock(&cache_chain_mutex);
-
if (__cache_shrink(cachep)) {
slab_error(cachep, "Can't free all objects");
- mutex_lock(&cache_chain_mutex);
list_add(&cachep->next, &cache_chain);
mutex_unlock(&cache_chain_mutex);
- unlock_cpu_hotplug();
return;
}
synchronize_rcu();
__kmem_cache_destroy(cachep);
- unlock_cpu_hotplug();
+ mutex_unlock(&cache_chain_mutex);
}
EXPORT_SYMBOL(kmem_cache_destroy);
cachep->ctor(objp, cachep, ctor_flags);
}
+#if ARCH_SLAB_MINALIGN
+ if ((u32)objp & (ARCH_SLAB_MINALIGN-1)) {
+ printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n",
+ objp, ARCH_SLAB_MINALIGN);
+ }
+#endif
return objp;
}
#else
int node;
struct kmem_list3 *l3;
struct array_cache *new_shared;
- struct array_cache **new_alien;
+ struct array_cache **new_alien = NULL;
for_each_online_node(node) {
- new_alien = alloc_alien_cache(node, cachep->limit);
- if (!new_alien)
- goto fail;
+ if (use_alien_caches) {
+ new_alien = alloc_alien_cache(node, cachep->limit);
+ if (!new_alien)
+ goto fail;
+ }
new_shared = alloc_arraycache(node,
cachep->shared*cachep->batchcount,
* If we cannot acquire the cache chain mutex then just give up - we'll try
* again on the next iteration.
*/
-static void cache_reap(void *unused)
+static void cache_reap(struct work_struct *unused)
{
struct kmem_cache *searchp;
struct kmem_list3 *l3;