diff options
| -rw-r--r-- | mm/slab.c | 123 |
1 files changed, 85 insertions, 38 deletions
diff --git a/mm/slab.c b/mm/slab.c index d3f68543f9f4..9cc049a942c6 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -884,14 +884,14 @@ static void __drain_alien_cache(struct kmem_cache *cachep, } } -static void drain_alien_cache(struct kmem_cache *cachep, struct kmem_list3 *l3) +static void drain_alien_cache(struct kmem_cache *cachep, struct array_cache **alien) { int i = 0; struct array_cache *ac; unsigned long flags; for_each_online_node(i) { - ac = l3->alien[i]; + ac = alien[i]; if (ac) { spin_lock_irqsave(&ac->lock, flags); __drain_alien_cache(cachep, ac, i); @@ -901,8 +901,11 @@ static void drain_alien_cache(struct kmem_cache *cachep, struct kmem_list3 *l3) } #else #define alloc_alien_cache(node, limit) do { } while (0) -#define free_alien_cache(ac_ptr) do { } while (0) -#define drain_alien_cache(cachep, l3) do { } while (0) +#define drain_alien_cache(cachep, alien) do { } while (0) + +static inline void free_alien_cache(struct array_cache **ac_ptr) +{ +} #endif static int __devinit cpuup_callback(struct notifier_block *nfb, @@ -936,6 +939,11 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + ((unsigned long)cachep) % REAPTIMEOUT_LIST3; + /* + * The l3s don't come and go as CPUs come and + * go. cache_chain_mutex is sufficient + * protection here. + */ cachep->nodelists[node] = l3; } @@ -950,26 +958,47 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, & array cache's */ list_for_each_entry(cachep, &cache_chain, next) { struct array_cache *nc; + struct array_cache *shared; + struct array_cache **alien; nc = alloc_arraycache(node, cachep->limit, - cachep->batchcount); + cachep->batchcount); if (!nc) goto bad; + shared = alloc_arraycache(node, + cachep->shared * cachep->batchcount, + 0xbaadf00d); + if (!shared) + goto bad; +#ifdef CONFIG_NUMA + alien = alloc_alien_cache(node, cachep->limit); + if (!alien) + goto bad; +#endif cachep->array[cpu] = nc; l3 = cachep->nodelists[node]; BUG_ON(!l3); - if (!l3->shared) { - if (!(nc = alloc_arraycache(node, - cachep->shared * - cachep->batchcount, - 0xbaadf00d))) - goto bad; - /* we are serialised from CPU_DEAD or - CPU_UP_CANCELLED by the cpucontrol lock */ - l3->shared = nc; + spin_lock_irq(&l3->list_lock); + if (!l3->shared) { + /* + * We are serialised from CPU_DEAD or + * CPU_UP_CANCELLED by the cpucontrol lock + */ + l3->shared = shared; + shared = NULL; } +#ifdef CONFIG_NUMA + if (!l3->alien) { + l3->alien = alien; + alien = NULL; + } +#endif + spin_unlock_irq(&l3->list_lock); + + kfree(shared); + free_alien_cache(alien); } mutex_unlock(&cache_chain_mutex); break; @@ -978,23 +1007,32 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, break; #ifdef CONFIG_HOTPLUG_CPU case CPU_DEAD: + /* + * Even if all the cpus of a node are down, we don't free the + * kmem_list3 of any cache. This to avoid a race between + * cpu_down, and a kmalloc allocation from another cpu for + * memory from the node of the cpu going down. The list3 + * structure is usually allocated from kmem_cache_create() and + * gets destroyed at kmem_cache_destroy(). + */ /* fall thru */ 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; + struct array_cache **alien; cpumask_t mask; mask = node_to_cpumask(node); - spin_lock(&cachep->spinlock); /* cpu is dead; no one can alloc from it. */ nc = cachep->array[cpu]; cachep->array[cpu] = NULL; l3 = cachep->nodelists[node]; if (!l3) - goto unlock_cache; + goto free_array_cache; spin_lock_irq(&l3->list_lock); @@ -1005,33 +1043,43 @@ static int __devinit cpuup_callback(struct notifier_block *nfb, if (!cpus_empty(mask)) { spin_unlock_irq(&l3->list_lock); - goto unlock_cache; + goto free_array_cache; } - if (l3->shared) { + shared = l3->shared; + if (shared) { free_block(cachep, l3->shared->entry, l3->shared->avail, node); - kfree(l3->shared); l3->shared = NULL; } - if (l3->alien) { - drain_alien_cache(cachep, l3); - free_alien_cache(l3->alien); - l3->alien = NULL; - } - /* free slabs belonging to this node */ - if (__node_shrink(cachep, node)) { - cachep->nodelists[node] = NULL; - spin_unlock_irq(&l3->list_lock); - kfree(l3); - } else { - spin_unlock_irq(&l3->list_lock); + alien = l3->alien; + l3->alien = NULL; + + spin_unlock_irq(&l3->list_lock); + + kfree(shared); + if (alien) { + drain_alien_cache(cachep, alien); + free_alien_cache(alien); } - unlock_cache: - spin_unlock(&cachep->spinlock); +free_array_cache: kfree(nc); } + /* + * In the previous loop, all the objects were freed to + * the respective cache's slabs, now we can go ahead and + * shrink each nodelist to its limit. + */ + list_for_each_entry(cachep, &cache_chain, next) { + l3 = cachep->nodelists[node]; + if (!l3) + continue; + spin_lock_irq(&l3->list_lock); + /* free slabs belonging to this node */ + __node_shrink(cachep, node); + spin_unlock_irq(&l3->list_lock); + } mutex_unlock(&cache_chain_mutex); break; #endif @@ -2011,7 +2059,6 @@ static void drain_cpu_caches(struct kmem_cache *cachep) smp_call_function_all_cpus(do_drain, cachep); check_irq_on(); - spin_lock(&cachep->spinlock); for_each_online_node(node) { l3 = cachep->nodelists[node]; if (l3) { @@ -2019,10 +2066,9 @@ static void drain_cpu_caches(struct kmem_cache *cachep) drain_array_locked(cachep, l3->shared, 1, node); spin_unlock_irq(&l3->list_lock); if (l3->alien) - drain_alien_cache(cachep, l3); + drain_alien_cache(cachep, l3->alien); } } - spin_unlock(&cachep->spinlock); } static int __node_shrink(struct kmem_cache *cachep, int node) @@ -3440,7 +3486,7 @@ static void cache_reap(void *unused) l3 = searchp->nodelists[numa_node_id()]; if (l3->alien) - drain_alien_cache(searchp, l3); + drain_alien_cache(searchp, l3->alien); spin_lock_irq(&l3->list_lock); drain_array_locked(searchp, cpu_cache_get(searchp), 0, @@ -3598,7 +3644,8 @@ static int s_show(struct seq_file *m, void *p) num_slabs++; } free_objects += l3->free_objects; - shared_avail += l3->shared->avail; + if (l3->shared) + shared_avail += l3->shared->avail; spin_unlock_irq(&l3->list_lock); } |