diff options
Diffstat (limited to 'mm/slab.c')
-rw-r--r-- | mm/slab.c | 266 |
1 files changed, 186 insertions, 80 deletions
diff --git a/mm/slab.c b/mm/slab.c index 83311c9aaf9d..5f0c5ef303d4 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -116,6 +116,7 @@ #include <linux/kmemcheck.h> #include <linux/memory.h> #include <linux/prefetch.h> +#include <linux/locallock.h> #include <asm/cacheflush.h> #include <asm/tlbflush.h> @@ -607,6 +608,12 @@ int slab_is_available(void) return g_cpucache_up >= EARLY; } +/* + * Guard access to the cache-chain. + */ +static DEFINE_MUTEX(cache_chain_mutex); +static struct list_head cache_chain; + #ifdef CONFIG_LOCKDEP /* @@ -668,38 +675,41 @@ static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep) slab_set_debugobj_lock_classes_node(cachep, node); } -static void init_node_lock_keys(int q) +static void init_lock_keys(struct kmem_cache *cachep, int node) { - struct cache_sizes *s = malloc_sizes; + struct kmem_list3 *l3; if (g_cpucache_up < LATE) return; - for (s = malloc_sizes; s->cs_size != ULONG_MAX; s++) { - struct kmem_list3 *l3; + l3 = cachep->nodelists[node]; + if (!l3 || OFF_SLAB(cachep)) + return; - l3 = s->cs_cachep->nodelists[q]; - if (!l3 || OFF_SLAB(s->cs_cachep)) - continue; + slab_set_lock_classes(cachep, &on_slab_l3_key, &on_slab_alc_key, node); +} - slab_set_lock_classes(s->cs_cachep, &on_slab_l3_key, - &on_slab_alc_key, q); - } +static void init_node_lock_keys(int node) +{ + struct kmem_cache *cachep; + + list_for_each_entry(cachep, &cache_chain, next) + init_lock_keys(cachep, node); } -static inline void init_lock_keys(void) +static inline void init_cachep_lock_keys(struct kmem_cache *cachep) { int node; for_each_node(node) - init_node_lock_keys(node); + init_lock_keys(cachep, node); } #else -static void init_node_lock_keys(int q) +static void init_node_lock_keys(int node) { } -static inline void init_lock_keys(void) +static void init_cachep_lock_keys(struct kmem_cache *cachep) { } @@ -712,19 +722,67 @@ static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep) } #endif +static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); +static DEFINE_PER_CPU(struct list_head, slab_free_list); +static DEFINE_LOCAL_IRQ_LOCK(slab_lock); + +#ifndef CONFIG_PREEMPT_RT_BASE +# define slab_on_each_cpu(func, cp) on_each_cpu(func, cp, 1) +#else /* - * Guard access to the cache-chain. + * execute func() for all CPUs. On PREEMPT_RT we dont actually have + * to run on the remote CPUs - we only have to take their CPU-locks. + * (This is a rare operation, so cacheline bouncing is not an issue.) */ -static DEFINE_MUTEX(cache_chain_mutex); -static struct list_head cache_chain; +static void +slab_on_each_cpu(void (*func)(void *arg, int this_cpu), void *arg) +{ + unsigned int i; -static DEFINE_PER_CPU(struct delayed_work, slab_reap_work); + for_each_online_cpu(i) + func(arg, i); +} +#endif + +static void free_delayed(struct list_head *h) +{ + while(!list_empty(h)) { + struct page *page = list_first_entry(h, struct page, lru); + + list_del(&page->lru); + __free_pages(page, page->index); + } +} + +static void unlock_l3_and_free_delayed(spinlock_t *list_lock) +{ + LIST_HEAD(tmp); + + list_splice_init(&__get_cpu_var(slab_free_list), &tmp); + local_spin_unlock_irq(slab_lock, list_lock); + free_delayed(&tmp); +} + +static void unlock_slab_and_free_delayed(unsigned long flags) +{ + LIST_HEAD(tmp); + + list_splice_init(&__get_cpu_var(slab_free_list), &tmp); + local_unlock_irqrestore(slab_lock, flags); + free_delayed(&tmp); +} static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) { return cachep->array[smp_processor_id()]; } +static inline struct array_cache *cpu_cache_get_on_cpu(struct kmem_cache *cachep, + int cpu) +{ + return cachep->array[cpu]; +} + static inline struct kmem_cache *__find_general_cachep(size_t size, gfp_t gfpflags) { @@ -1062,9 +1120,10 @@ static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3) if (l3->alien) { struct array_cache *ac = l3->alien[node]; - if (ac && ac->avail && spin_trylock_irq(&ac->lock)) { + if (ac && ac->avail && + local_spin_trylock_irq(slab_lock, &ac->lock)) { __drain_alien_cache(cachep, ac, node); - spin_unlock_irq(&ac->lock); + local_spin_unlock_irq(slab_lock, &ac->lock); } } } @@ -1079,9 +1138,9 @@ static void drain_alien_cache(struct kmem_cache *cachep, for_each_online_node(i) { ac = alien[i]; if (ac) { - spin_lock_irqsave(&ac->lock, flags); + local_spin_lock_irqsave(slab_lock, &ac->lock, flags); __drain_alien_cache(cachep, ac, i); - spin_unlock_irqrestore(&ac->lock, flags); + local_spin_unlock_irqrestore(slab_lock, &ac->lock, flags); } } } @@ -1160,11 +1219,11 @@ static int init_cache_nodelists_node(int node) cachep->nodelists[node] = l3; } - spin_lock_irq(&cachep->nodelists[node]->list_lock); + local_spin_lock_irq(slab_lock, &cachep->nodelists[node]->list_lock); cachep->nodelists[node]->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; - spin_unlock_irq(&cachep->nodelists[node]->list_lock); + local_spin_unlock_irq(slab_lock, &cachep->nodelists[node]->list_lock); } return 0; } @@ -1189,7 +1248,7 @@ static void __cpuinit cpuup_canceled(long cpu) if (!l3) goto free_array_cache; - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); /* Free limit for this kmem_list3 */ l3->free_limit -= cachep->batchcount; @@ -1197,7 +1256,7 @@ static void __cpuinit cpuup_canceled(long cpu) free_block(cachep, nc->entry, nc->avail, node); if (!cpumask_empty(mask)) { - spin_unlock_irq(&l3->list_lock); + unlock_l3_and_free_delayed(&l3->list_lock); goto free_array_cache; } @@ -1211,7 +1270,7 @@ static void __cpuinit cpuup_canceled(long cpu) alien = l3->alien; l3->alien = NULL; - spin_unlock_irq(&l3->list_lock); + unlock_l3_and_free_delayed(&l3->list_lock); kfree(shared); if (alien) { @@ -1285,7 +1344,7 @@ static int __cpuinit cpuup_prepare(long cpu) l3 = cachep->nodelists[node]; BUG_ON(!l3); - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); if (!l3->shared) { /* * We are serialised from CPU_DEAD or @@ -1300,7 +1359,7 @@ static int __cpuinit cpuup_prepare(long cpu) alien = NULL; } #endif - spin_unlock_irq(&l3->list_lock); + local_spin_unlock_irq(slab_lock, &l3->list_lock); kfree(shared); free_alien_cache(alien); if (cachep->flags & SLAB_DEBUG_OBJECTS) @@ -1491,6 +1550,10 @@ void __init kmem_cache_init(void) if (num_possible_nodes() == 1) use_alien_caches = 0; + local_irq_lock_init(slab_lock); + for_each_possible_cpu(i) + INIT_LIST_HEAD(&per_cpu(slab_free_list, i)); + for (i = 0; i < NUM_INIT_LISTS; i++) { kmem_list3_init(&initkmem_list3[i]); if (i < MAX_NUMNODES) @@ -1669,14 +1732,13 @@ void __init kmem_cache_init_late(void) g_cpucache_up = LATE; - /* Annotate slab for lockdep -- annotate the malloc caches */ - init_lock_keys(); - /* 6) resize the head arrays to their final sizes */ mutex_lock(&cache_chain_mutex); - list_for_each_entry(cachep, &cache_chain, next) + list_for_each_entry(cachep, &cache_chain, next) { + init_cachep_lock_keys(cachep); if (enable_cpucache(cachep, GFP_NOWAIT)) BUG(); + } mutex_unlock(&cache_chain_mutex); /* Done! */ @@ -1769,12 +1831,14 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) /* * Interface to system's page release. */ -static void kmem_freepages(struct kmem_cache *cachep, void *addr) +static void kmem_freepages(struct kmem_cache *cachep, void *addr, bool delayed) { unsigned long i = (1 << cachep->gfporder); - struct page *page = virt_to_page(addr); + struct page *page, *basepage = virt_to_page(addr); const unsigned long nr_freed = i; + page = basepage; + kmemcheck_free_shadow(page, cachep->gfporder); if (cachep->flags & SLAB_RECLAIM_ACCOUNT) @@ -1790,7 +1854,13 @@ static void kmem_freepages(struct kmem_cache *cachep, void *addr) } if (current->reclaim_state) current->reclaim_state->reclaimed_slab += nr_freed; - free_pages((unsigned long)addr, cachep->gfporder); + + if (!delayed) { + free_pages((unsigned long)addr, cachep->gfporder); + } else { + basepage->index = cachep->gfporder; + list_add(&basepage->lru, &__get_cpu_var(slab_free_list)); + } } static void kmem_rcu_free(struct rcu_head *head) @@ -1798,7 +1868,7 @@ static void kmem_rcu_free(struct rcu_head *head) struct slab_rcu *slab_rcu = (struct slab_rcu *)head; struct kmem_cache *cachep = slab_rcu->cachep; - kmem_freepages(cachep, slab_rcu->addr); + kmem_freepages(cachep, slab_rcu->addr, false); if (OFF_SLAB(cachep)) kmem_cache_free(cachep->slabp_cache, slab_rcu); } @@ -2017,7 +2087,8 @@ static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slab * Before calling the slab must have been unlinked from the cache. The * cache-lock is not held/needed. */ -static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp) +static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp, + bool delayed) { void *addr = slabp->s_mem - slabp->colouroff; @@ -2030,7 +2101,7 @@ static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp) slab_rcu->addr = addr; call_rcu(&slab_rcu->head, kmem_rcu_free); } else { - kmem_freepages(cachep, addr); + kmem_freepages(cachep, addr, delayed); if (OFF_SLAB(cachep)) kmem_cache_free(cachep->slabp_cache, slabp); } @@ -2479,6 +2550,8 @@ kmem_cache_create (const char *name, size_t size, size_t align, slab_set_debugobj_lock_classes(cachep); } + init_cachep_lock_keys(cachep); + /* cache setup completed, link it into the list */ list_add(&cachep->next, &cache_chain); oops: @@ -2496,7 +2569,7 @@ EXPORT_SYMBOL(kmem_cache_create); #if DEBUG static void check_irq_off(void) { - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); } static void check_irq_on(void) @@ -2531,26 +2604,43 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, struct array_cache *ac, int force, int node); -static void do_drain(void *arg) +static void __do_drain(void *arg, unsigned int cpu) { struct kmem_cache *cachep = arg; struct array_cache *ac; - int node = numa_mem_id(); + int node = cpu_to_mem(cpu); - check_irq_off(); - ac = cpu_cache_get(cachep); + ac = cpu_cache_get_on_cpu(cachep, cpu); spin_lock(&cachep->nodelists[node]->list_lock); free_block(cachep, ac->entry, ac->avail, node); spin_unlock(&cachep->nodelists[node]->list_lock); ac->avail = 0; } +#ifndef CONFIG_PREEMPT_RT_BASE +static void do_drain(void *arg) +{ + __do_drain(arg, smp_processor_id()); +} +#else +static void do_drain(void *arg, int cpu) +{ + LIST_HEAD(tmp); + + spin_lock_irq(&per_cpu(slab_lock, cpu).lock); + __do_drain(arg, cpu); + list_splice_init(&per_cpu(slab_free_list, cpu), &tmp); + spin_unlock_irq(&per_cpu(slab_lock, cpu).lock); + free_delayed(&tmp); +} +#endif + static void drain_cpu_caches(struct kmem_cache *cachep) { struct kmem_list3 *l3; int node; - on_each_cpu(do_drain, cachep, 1); + slab_on_each_cpu(do_drain, cachep); check_irq_on(); for_each_online_node(node) { l3 = cachep->nodelists[node]; @@ -2581,10 +2671,10 @@ static int drain_freelist(struct kmem_cache *cache, nr_freed = 0; while (nr_freed < tofree && !list_empty(&l3->slabs_free)) { - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); p = l3->slabs_free.prev; if (p == &l3->slabs_free) { - spin_unlock_irq(&l3->list_lock); + local_spin_unlock_irq(slab_lock, &l3->list_lock); goto out; } @@ -2598,8 +2688,8 @@ static int drain_freelist(struct kmem_cache *cache, * to the cache. */ l3->free_objects -= cache->num; - spin_unlock_irq(&l3->list_lock); - slab_destroy(cache, slabp); + local_spin_unlock_irq(slab_lock, &l3->list_lock); + slab_destroy(cache, slabp, false); nr_freed++; } out: @@ -2893,7 +2983,7 @@ static int cache_grow(struct kmem_cache *cachep, offset *= cachep->colour_off; if (local_flags & __GFP_WAIT) - local_irq_enable(); + local_unlock_irq(slab_lock); /* * The test for missing atomic flag is performed here, rather than @@ -2923,7 +3013,7 @@ static int cache_grow(struct kmem_cache *cachep, cache_init_objs(cachep, slabp); if (local_flags & __GFP_WAIT) - local_irq_disable(); + local_lock_irq(slab_lock); check_irq_off(); spin_lock(&l3->list_lock); @@ -2934,10 +3024,10 @@ static int cache_grow(struct kmem_cache *cachep, spin_unlock(&l3->list_lock); return 1; opps1: - kmem_freepages(cachep, objp); + kmem_freepages(cachep, objp, false); failed: if (local_flags & __GFP_WAIT) - local_irq_disable(); + local_lock_irq(slab_lock); return 0; } @@ -3329,11 +3419,11 @@ retry: * set and go into memory reserves if necessary. */ if (local_flags & __GFP_WAIT) - local_irq_enable(); + local_unlock_irq(slab_lock); kmem_flagcheck(cache, flags); obj = kmem_getpages(cache, local_flags, numa_mem_id()); if (local_flags & __GFP_WAIT) - local_irq_disable(); + local_lock_irq(slab_lock); if (obj) { /* * Insert into the appropriate per node queues @@ -3449,7 +3539,7 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, return NULL; cache_alloc_debugcheck_before(cachep, flags); - local_irq_save(save_flags); + local_lock_irqsave(slab_lock, save_flags); if (nodeid == NUMA_NO_NODE) nodeid = slab_node; @@ -3474,7 +3564,7 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, /* ___cache_alloc_node can fall back to other nodes */ ptr = ____cache_alloc_node(cachep, flags, nodeid); out: - local_irq_restore(save_flags); + local_unlock_irqrestore(slab_lock, save_flags); ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, caller); kmemleak_alloc_recursive(ptr, obj_size(cachep), 1, cachep->flags, flags); @@ -3534,9 +3624,9 @@ __cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller) return NULL; cache_alloc_debugcheck_before(cachep, flags); - local_irq_save(save_flags); + local_lock_irqsave(slab_lock, save_flags); objp = __do_cache_alloc(cachep, flags); - local_irq_restore(save_flags); + local_unlock_irqrestore(slab_lock, save_flags); objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); kmemleak_alloc_recursive(objp, obj_size(cachep), 1, cachep->flags, flags); @@ -3584,7 +3674,7 @@ static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects, * a different cache, refer to comments before * alloc_slabmgmt. */ - slab_destroy(cachep, slabp); + slab_destroy(cachep, slabp, true); } else { list_add(&slabp->list, &l3->slabs_free); } @@ -3847,12 +3937,12 @@ void kmem_cache_free(struct kmem_cache *cachep, void *objp) { unsigned long flags; - local_irq_save(flags); debug_check_no_locks_freed(objp, obj_size(cachep)); if (!(cachep->flags & SLAB_DEBUG_OBJECTS)) debug_check_no_obj_freed(objp, obj_size(cachep)); + local_lock_irqsave(slab_lock, flags); __cache_free(cachep, objp, __builtin_return_address(0)); - local_irq_restore(flags); + unlock_slab_and_free_delayed(flags); trace_kmem_cache_free(_RET_IP_, objp); } @@ -3876,13 +3966,13 @@ void kfree(const void *objp) if (unlikely(ZERO_OR_NULL_PTR(objp))) return; - local_irq_save(flags); kfree_debugcheck(objp); c = virt_to_cache(objp); debug_check_no_locks_freed(objp, obj_size(c)); debug_check_no_obj_freed(objp, obj_size(c)); + local_lock_irqsave(slab_lock, flags); __cache_free(c, (void *)objp, __builtin_return_address(0)); - local_irq_restore(flags); + unlock_slab_and_free_delayed(flags); } EXPORT_SYMBOL(kfree); @@ -3925,7 +4015,7 @@ static int alloc_kmemlist(struct kmem_cache *cachep, gfp_t gfp) if (l3) { struct array_cache *shared = l3->shared; - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); if (shared) free_block(cachep, shared->entry, @@ -3938,7 +4028,8 @@ static int alloc_kmemlist(struct kmem_cache *cachep, gfp_t gfp) } l3->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount + cachep->num; - spin_unlock_irq(&l3->list_lock); + unlock_l3_and_free_delayed(&l3->list_lock); + kfree(shared); free_alien_cache(new_alien); continue; @@ -3985,17 +4076,30 @@ struct ccupdate_struct { struct array_cache *new[0]; }; -static void do_ccupdate_local(void *info) +static void __do_ccupdate_local(void *info, int cpu) { struct ccupdate_struct *new = info; struct array_cache *old; - check_irq_off(); - old = cpu_cache_get(new->cachep); + old = cpu_cache_get_on_cpu(new->cachep, cpu); + + new->cachep->array[cpu] = new->new[cpu]; + new->new[cpu] = old; +} - new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; - new->new[smp_processor_id()] = old; +#ifndef CONFIG_PREEMPT_RT_BASE +static void do_ccupdate_local(void *info) +{ + __do_ccupdate_local(info, smp_processor_id()); } +#else +static void do_ccupdate_local(void *info, int cpu) +{ + spin_lock_irq(&per_cpu(slab_lock, cpu).lock); + __do_ccupdate_local(info, cpu); + spin_unlock_irq(&per_cpu(slab_lock, cpu).lock); +} +#endif /* Always called with the cache_chain_mutex held */ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, @@ -4021,7 +4125,7 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, } new->cachep = cachep; - on_each_cpu(do_ccupdate_local, (void *)new, 1); + slab_on_each_cpu(do_ccupdate_local, (void *)new); check_irq_on(); cachep->batchcount = batchcount; @@ -4032,9 +4136,11 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, struct array_cache *ccold = new->new[i]; if (!ccold) continue; - spin_lock_irq(&cachep->nodelists[cpu_to_mem(i)]->list_lock); + local_spin_lock_irq(slab_lock, + &cachep->nodelists[cpu_to_mem(i)]->list_lock); free_block(cachep, ccold->entry, ccold->avail, cpu_to_mem(i)); - spin_unlock_irq(&cachep->nodelists[cpu_to_mem(i)]->list_lock); + + unlock_l3_and_free_delayed(&cachep->nodelists[cpu_to_mem(i)]->list_lock); kfree(ccold); } kfree(new); @@ -4110,7 +4216,7 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, if (ac->touched && !force) { ac->touched = 0; } else { - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); if (ac->avail) { tofree = force ? ac->avail : (ac->limit + 4) / 5; if (tofree > ac->avail) @@ -4120,7 +4226,7 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, memmove(ac->entry, &(ac->entry[tofree]), sizeof(void *) * ac->avail); } - spin_unlock_irq(&l3->list_lock); + local_spin_unlock_irq(slab_lock, &l3->list_lock); } } @@ -4259,7 +4365,7 @@ static int s_show(struct seq_file *m, void *p) continue; check_irq_on(); - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); list_for_each_entry(slabp, &l3->slabs_full, list) { if (slabp->inuse != cachep->num && !error) @@ -4284,7 +4390,7 @@ static int s_show(struct seq_file *m, void *p) if (l3->shared) shared_avail += l3->shared->avail; - spin_unlock_irq(&l3->list_lock); + local_spin_unlock_irq(slab_lock, &l3->list_lock); } num_slabs += active_slabs; num_objs = num_slabs * cachep->num; @@ -4513,13 +4619,13 @@ static int leaks_show(struct seq_file *m, void *p) continue; check_irq_on(); - spin_lock_irq(&l3->list_lock); + local_spin_lock_irq(slab_lock, &l3->list_lock); list_for_each_entry(slabp, &l3->slabs_full, list) handle_slab(n, cachep, slabp); list_for_each_entry(slabp, &l3->slabs_partial, list) handle_slab(n, cachep, slabp); - spin_unlock_irq(&l3->list_lock); + local_spin_unlock_irq(slab_lock, &l3->list_lock); } name = cachep->name; if (n[0] == n[1]) { |