diff options
Diffstat (limited to 'mm/slub.c')
-rw-r--r-- | mm/slub.c | 337 |
1 files changed, 104 insertions, 233 deletions
diff --git a/mm/slub.c b/mm/slub.c index 8d71aaf888d7..3525a4ec9794 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -151,7 +151,8 @@ * Set of flags that will prevent slab merging */ #define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ - SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE) + SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \ + SLAB_FAILSLAB) #define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \ SLAB_CACHE_DMA | SLAB_NOTRACK) @@ -217,10 +218,10 @@ static inline void sysfs_slab_remove(struct kmem_cache *s) #endif -static inline void stat(struct kmem_cache_cpu *c, enum stat_item si) +static inline void stat(struct kmem_cache *s, enum stat_item si) { #ifdef CONFIG_SLUB_STATS - c->stat[si]++; + __this_cpu_inc(s->cpu_slab->stat[si]); #endif } @@ -242,15 +243,6 @@ static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) #endif } -static inline struct kmem_cache_cpu *get_cpu_slab(struct kmem_cache *s, int cpu) -{ -#ifdef CONFIG_SMP - return s->cpu_slab[cpu]; -#else - return &s->cpu_slab; -#endif -} - /* Verify that a pointer has an address that is valid within a slab page */ static inline int check_valid_pointer(struct kmem_cache *s, struct page *page, const void *object) @@ -269,13 +261,6 @@ static inline int check_valid_pointer(struct kmem_cache *s, return 1; } -/* - * Slow version of get and set free pointer. - * - * This version requires touching the cache lines of kmem_cache which - * we avoid to do in the fast alloc free paths. There we obtain the offset - * from the page struct. - */ static inline void *get_freepointer(struct kmem_cache *s, void *object) { return *(void **)(object + s->offset); @@ -1020,6 +1005,9 @@ static int __init setup_slub_debug(char *str) case 't': slub_debug |= SLAB_TRACE; break; + case 'a': + slub_debug |= SLAB_FAILSLAB; + break; default: printk(KERN_ERR "slub_debug option '%c' " "unknown. skipped\n", *str); @@ -1124,7 +1112,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) if (!page) return NULL; - stat(get_cpu_slab(s, raw_smp_processor_id()), ORDER_FALLBACK); + stat(s, ORDER_FALLBACK); } if (kmemcheck_enabled @@ -1422,23 +1410,22 @@ static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node) static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) { struct kmem_cache_node *n = get_node(s, page_to_nid(page)); - struct kmem_cache_cpu *c = get_cpu_slab(s, smp_processor_id()); __ClearPageSlubFrozen(page); if (page->inuse) { if (page->freelist) { add_partial(n, page, tail); - stat(c, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); + stat(s, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); } else { - stat(c, DEACTIVATE_FULL); + stat(s, DEACTIVATE_FULL); if (SLABDEBUG && PageSlubDebug(page) && (s->flags & SLAB_STORE_USER)) add_full(n, page); } slab_unlock(page); } else { - stat(c, DEACTIVATE_EMPTY); + stat(s, DEACTIVATE_EMPTY); if (n->nr_partial < s->min_partial) { /* * Adding an empty slab to the partial slabs in order @@ -1454,7 +1441,7 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) slab_unlock(page); } else { slab_unlock(page); - stat(get_cpu_slab(s, raw_smp_processor_id()), FREE_SLAB); + stat(s, FREE_SLAB); discard_slab(s, page); } } @@ -1469,7 +1456,7 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) int tail = 1; if (page->freelist) - stat(c, DEACTIVATE_REMOTE_FREES); + stat(s, DEACTIVATE_REMOTE_FREES); /* * Merge cpu freelist into slab freelist. Typically we get here * because both freelists are empty. So this is unlikely @@ -1482,10 +1469,10 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) /* Retrieve object from cpu_freelist */ object = c->freelist; - c->freelist = c->freelist[c->offset]; + c->freelist = get_freepointer(s, c->freelist); /* And put onto the regular freelist */ - object[c->offset] = page->freelist; + set_freepointer(s, object, page->freelist); page->freelist = object; page->inuse--; } @@ -1495,7 +1482,7 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) { - stat(c, CPUSLAB_FLUSH); + stat(s, CPUSLAB_FLUSH); slab_lock(c->page); deactivate_slab(s, c); } @@ -1507,7 +1494,7 @@ static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) */ static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) { - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); + struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); if (likely(c && c->page)) flush_slab(s, c); @@ -1635,7 +1622,7 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, if (unlikely(!node_match(c, node))) goto another_slab; - stat(c, ALLOC_REFILL); + stat(s, ALLOC_REFILL); load_freelist: object = c->page->freelist; @@ -1644,13 +1631,13 @@ load_freelist: if (unlikely(SLABDEBUG && PageSlubDebug(c->page))) goto debug; - c->freelist = object[c->offset]; + c->freelist = get_freepointer(s, object); c->page->inuse = c->page->objects; c->page->freelist = NULL; c->node = page_to_nid(c->page); unlock_out: slab_unlock(c->page); - stat(c, ALLOC_SLOWPATH); + stat(s, ALLOC_SLOWPATH); return object; another_slab: @@ -1660,7 +1647,7 @@ new_slab: new = get_partial(s, gfpflags, node); if (new) { c->page = new; - stat(c, ALLOC_FROM_PARTIAL); + stat(s, ALLOC_FROM_PARTIAL); goto load_freelist; } @@ -1673,8 +1660,8 @@ new_slab: local_irq_disable(); if (new) { - c = get_cpu_slab(s, smp_processor_id()); - stat(c, ALLOC_SLAB); + c = __this_cpu_ptr(s->cpu_slab); + stat(s, ALLOC_SLAB); if (c->page) flush_slab(s, c); slab_lock(new); @@ -1690,7 +1677,7 @@ debug: goto another_slab; c->page->inuse++; - c->page->freelist = object[c->offset]; + c->page->freelist = get_freepointer(s, object); c->node = -1; goto unlock_out; } @@ -1711,35 +1698,33 @@ static __always_inline void *slab_alloc(struct kmem_cache *s, void **object; struct kmem_cache_cpu *c; unsigned long flags; - unsigned int objsize; gfpflags &= gfp_allowed_mask; lockdep_trace_alloc(gfpflags); might_sleep_if(gfpflags & __GFP_WAIT); - if (should_failslab(s->objsize, gfpflags)) + if (should_failslab(s->objsize, gfpflags, s->flags)) return NULL; local_irq_save(flags); - c = get_cpu_slab(s, smp_processor_id()); - objsize = c->objsize; - if (unlikely(!c->freelist || !node_match(c, node))) + c = __this_cpu_ptr(s->cpu_slab); + object = c->freelist; + if (unlikely(!object || !node_match(c, node))) object = __slab_alloc(s, gfpflags, node, addr, c); else { - object = c->freelist; - c->freelist = object[c->offset]; - stat(c, ALLOC_FASTPATH); + c->freelist = get_freepointer(s, object); + stat(s, ALLOC_FASTPATH); } local_irq_restore(flags); if (unlikely(gfpflags & __GFP_ZERO) && object) - memset(object, 0, objsize); + memset(object, 0, s->objsize); - kmemcheck_slab_alloc(s, gfpflags, object, c->objsize); - kmemleak_alloc_recursive(object, objsize, 1, s->flags, gfpflags); + kmemcheck_slab_alloc(s, gfpflags, object, s->objsize); + kmemleak_alloc_recursive(object, s->objsize, 1, s->flags, gfpflags); return object; } @@ -1794,26 +1779,25 @@ EXPORT_SYMBOL(kmem_cache_alloc_node_notrace); * handling required then we can return immediately. */ static void __slab_free(struct kmem_cache *s, struct page *page, - void *x, unsigned long addr, unsigned int offset) + void *x, unsigned long addr) { void *prior; void **object = (void *)x; - struct kmem_cache_cpu *c; - c = get_cpu_slab(s, raw_smp_processor_id()); - stat(c, FREE_SLOWPATH); + stat(s, FREE_SLOWPATH); slab_lock(page); if (unlikely(SLABDEBUG && PageSlubDebug(page))) goto debug; checks_ok: - prior = object[offset] = page->freelist; + prior = page->freelist; + set_freepointer(s, object, prior); page->freelist = object; page->inuse--; if (unlikely(PageSlubFrozen(page))) { - stat(c, FREE_FROZEN); + stat(s, FREE_FROZEN); goto out_unlock; } @@ -1826,7 +1810,7 @@ checks_ok: */ if (unlikely(!prior)) { add_partial(get_node(s, page_to_nid(page)), page, 1); - stat(c, FREE_ADD_PARTIAL); + stat(s, FREE_ADD_PARTIAL); } out_unlock: @@ -1839,10 +1823,10 @@ slab_empty: * Slab still on the partial list. */ remove_partial(s, page); - stat(c, FREE_REMOVE_PARTIAL); + stat(s, FREE_REMOVE_PARTIAL); } slab_unlock(page); - stat(c, FREE_SLAB); + stat(s, FREE_SLAB); discard_slab(s, page); return; @@ -1872,17 +1856,17 @@ static __always_inline void slab_free(struct kmem_cache *s, kmemleak_free_recursive(x, s->flags); local_irq_save(flags); - c = get_cpu_slab(s, smp_processor_id()); - kmemcheck_slab_free(s, object, c->objsize); - debug_check_no_locks_freed(object, c->objsize); + c = __this_cpu_ptr(s->cpu_slab); + kmemcheck_slab_free(s, object, s->objsize); + debug_check_no_locks_freed(object, s->objsize); if (!(s->flags & SLAB_DEBUG_OBJECTS)) - debug_check_no_obj_freed(object, c->objsize); + debug_check_no_obj_freed(object, s->objsize); if (likely(page == c->page && c->node >= 0)) { - object[c->offset] = c->freelist; + set_freepointer(s, object, c->freelist); c->freelist = object; - stat(c, FREE_FASTPATH); + stat(s, FREE_FASTPATH); } else - __slab_free(s, page, x, addr, c->offset); + __slab_free(s, page, x, addr); local_irq_restore(flags); } @@ -2069,19 +2053,6 @@ static unsigned long calculate_alignment(unsigned long flags, return ALIGN(align, sizeof(void *)); } -static void init_kmem_cache_cpu(struct kmem_cache *s, - struct kmem_cache_cpu *c) -{ - c->page = NULL; - c->freelist = NULL; - c->node = 0; - c->offset = s->offset / sizeof(void *); - c->objsize = s->objsize; -#ifdef CONFIG_SLUB_STATS - memset(c->stat, 0, NR_SLUB_STAT_ITEMS * sizeof(unsigned)); -#endif -} - static void init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s) { @@ -2095,130 +2066,24 @@ init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s) #endif } -#ifdef CONFIG_SMP -/* - * Per cpu array for per cpu structures. - * - * The per cpu array places all kmem_cache_cpu structures from one processor - * close together meaning that it becomes possible that multiple per cpu - * structures are contained in one cacheline. This may be particularly - * beneficial for the kmalloc caches. - * - * A desktop system typically has around 60-80 slabs. With 100 here we are - * likely able to get per cpu structures for all caches from the array defined - * here. We must be able to cover all kmalloc caches during bootstrap. - * - * If the per cpu array is exhausted then fall back to kmalloc - * of individual cachelines. No sharing is possible then. - */ -#define NR_KMEM_CACHE_CPU 100 - -static DEFINE_PER_CPU(struct kmem_cache_cpu [NR_KMEM_CACHE_CPU], - kmem_cache_cpu); - -static DEFINE_PER_CPU(struct kmem_cache_cpu *, kmem_cache_cpu_free); -static DECLARE_BITMAP(kmem_cach_cpu_free_init_once, CONFIG_NR_CPUS); - -static struct kmem_cache_cpu *alloc_kmem_cache_cpu(struct kmem_cache *s, - int cpu, gfp_t flags) -{ - struct kmem_cache_cpu *c = per_cpu(kmem_cache_cpu_free, cpu); - - if (c) - per_cpu(kmem_cache_cpu_free, cpu) = - (void *)c->freelist; - else { - /* Table overflow: So allocate ourselves */ - c = kmalloc_node( - ALIGN(sizeof(struct kmem_cache_cpu), cache_line_size()), - flags, cpu_to_node(cpu)); - if (!c) - return NULL; - } - - init_kmem_cache_cpu(s, c); - return c; -} - -static void free_kmem_cache_cpu(struct kmem_cache_cpu *c, int cpu) -{ - if (c < per_cpu(kmem_cache_cpu, cpu) || - c >= per_cpu(kmem_cache_cpu, cpu) + NR_KMEM_CACHE_CPU) { - kfree(c); - return; - } - c->freelist = (void *)per_cpu(kmem_cache_cpu_free, cpu); - per_cpu(kmem_cache_cpu_free, cpu) = c; -} - -static void free_kmem_cache_cpus(struct kmem_cache *s) -{ - int cpu; - - for_each_online_cpu(cpu) { - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); - - if (c) { - s->cpu_slab[cpu] = NULL; - free_kmem_cache_cpu(c, cpu); - } - } -} - -static int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags) -{ - int cpu; - - for_each_online_cpu(cpu) { - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); - - if (c) - continue; - - c = alloc_kmem_cache_cpu(s, cpu, flags); - if (!c) { - free_kmem_cache_cpus(s); - return 0; - } - s->cpu_slab[cpu] = c; - } - return 1; -} - -/* - * Initialize the per cpu array. - */ -static void init_alloc_cpu_cpu(int cpu) -{ - int i; +static DEFINE_PER_CPU(struct kmem_cache_cpu, kmalloc_percpu[KMALLOC_CACHES]); - if (cpumask_test_cpu(cpu, to_cpumask(kmem_cach_cpu_free_init_once))) - return; - - for (i = NR_KMEM_CACHE_CPU - 1; i >= 0; i--) - free_kmem_cache_cpu(&per_cpu(kmem_cache_cpu, cpu)[i], cpu); - - cpumask_set_cpu(cpu, to_cpumask(kmem_cach_cpu_free_init_once)); -} - -static void __init init_alloc_cpu(void) +static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags) { - int cpu; - - for_each_online_cpu(cpu) - init_alloc_cpu_cpu(cpu); - } + if (s < kmalloc_caches + KMALLOC_CACHES && s >= kmalloc_caches) + /* + * Boot time creation of the kmalloc array. Use static per cpu data + * since the per cpu allocator is not available yet. + */ + s->cpu_slab = per_cpu_var(kmalloc_percpu) + (s - kmalloc_caches); + else + s->cpu_slab = alloc_percpu(struct kmem_cache_cpu); -#else -static inline void free_kmem_cache_cpus(struct kmem_cache *s) {} -static inline void init_alloc_cpu(void) {} + if (!s->cpu_slab) + return 0; -static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags) -{ - init_kmem_cache_cpu(s, &s->cpu_slab); return 1; } -#endif #ifdef CONFIG_NUMA /* @@ -2287,7 +2152,8 @@ static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) int node; int local_node; - if (slab_state >= UP) + if (slab_state >= UP && (s < kmalloc_caches || + s > kmalloc_caches + KMALLOC_CACHES)) local_node = page_to_nid(virt_to_page(s)); else local_node = 0; @@ -2502,6 +2368,7 @@ static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, if (alloc_kmem_cache_cpus(s, gfpflags & ~SLUB_DMA)) return 1; + free_kmem_cache_nodes(s); error: if (flags & SLAB_PANIC) @@ -2609,9 +2476,8 @@ static inline int kmem_cache_close(struct kmem_cache *s) int node; flush_all(s); - + free_percpu(s->cpu_slab); /* Attempt to free all objects */ - free_kmem_cache_cpus(s); for_each_node_state(node, N_NORMAL_MEMORY) { struct kmem_cache_node *n = get_node(s, node); @@ -2651,7 +2517,7 @@ EXPORT_SYMBOL(kmem_cache_destroy); * Kmalloc subsystem *******************************************************************/ -struct kmem_cache kmalloc_caches[SLUB_PAGE_SHIFT] __cacheline_aligned; +struct kmem_cache kmalloc_caches[KMALLOC_CACHES] __cacheline_aligned; EXPORT_SYMBOL(kmalloc_caches); static int __init setup_slub_min_order(char *str) @@ -2741,6 +2607,7 @@ static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags) char *text; size_t realsize; unsigned long slabflags; + int i; s = kmalloc_caches_dma[index]; if (s) @@ -2760,7 +2627,14 @@ static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags) realsize = kmalloc_caches[index].objsize; text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", (unsigned int)realsize); - s = kmalloc(kmem_size, flags & ~SLUB_DMA); + + s = NULL; + for (i = 0; i < KMALLOC_CACHES; i++) + if (!kmalloc_caches[i].size) + break; + + BUG_ON(i >= KMALLOC_CACHES); + s = kmalloc_caches + i; /* * Must defer sysfs creation to a workqueue because we don't know @@ -2772,9 +2646,9 @@ static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags) if (slab_state >= SYSFS) slabflags |= __SYSFS_ADD_DEFERRED; - if (!s || !text || !kmem_cache_open(s, flags, text, + if (!text || !kmem_cache_open(s, flags, text, realsize, ARCH_KMALLOC_MINALIGN, slabflags, NULL)) { - kfree(s); + s->size = 0; kfree(text); goto unlock_out; } @@ -3176,8 +3050,6 @@ void __init kmem_cache_init(void) int i; int caches = 0; - init_alloc_cpu(); - #ifdef CONFIG_NUMA /* * Must first have the slab cache available for the allocations of the @@ -3261,8 +3133,10 @@ void __init kmem_cache_init(void) #ifdef CONFIG_SMP register_cpu_notifier(&slab_notifier); - kmem_size = offsetof(struct kmem_cache, cpu_slab) + - nr_cpu_ids * sizeof(struct kmem_cache_cpu *); +#endif +#ifdef CONFIG_NUMA + kmem_size = offsetof(struct kmem_cache, node) + + nr_node_ids * sizeof(struct kmem_cache_node *); #else kmem_size = sizeof(struct kmem_cache); #endif @@ -3351,22 +3225,12 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size, down_write(&slub_lock); s = find_mergeable(size, align, flags, name, ctor); if (s) { - int cpu; - s->refcount++; /* * Adjust the object sizes so that we clear * the complete object on kzalloc. */ s->objsize = max(s->objsize, (int)size); - - /* - * And then we need to update the object size in the - * per cpu structures - */ - for_each_online_cpu(cpu) - get_cpu_slab(s, cpu)->objsize = s->objsize; - s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *))); up_write(&slub_lock); @@ -3420,29 +3284,15 @@ static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb, unsigned long flags; switch (action) { - case CPU_UP_PREPARE: - case CPU_UP_PREPARE_FROZEN: - init_alloc_cpu_cpu(cpu); - down_read(&slub_lock); - list_for_each_entry(s, &slab_caches, list) - s->cpu_slab[cpu] = alloc_kmem_cache_cpu(s, cpu, - GFP_KERNEL); - up_read(&slub_lock); - break; - case CPU_UP_CANCELED: case CPU_UP_CANCELED_FROZEN: case CPU_DEAD: case CPU_DEAD_FROZEN: down_read(&slub_lock); list_for_each_entry(s, &slab_caches, list) { - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); - local_irq_save(flags); __flush_cpu_slab(s, cpu); local_irq_restore(flags); - free_kmem_cache_cpu(c, cpu); - s->cpu_slab[cpu] = NULL; } up_read(&slub_lock); break; @@ -3928,7 +3778,7 @@ static ssize_t show_slab_objects(struct kmem_cache *s, int cpu; for_each_possible_cpu(cpu) { - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); + struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); if (!c || c->node < 0) continue; @@ -4171,6 +4021,23 @@ static ssize_t trace_store(struct kmem_cache *s, const char *buf, } SLAB_ATTR(trace); +#ifdef CONFIG_FAILSLAB +static ssize_t failslab_show(struct kmem_cache *s, char *buf) +{ + return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); +} + +static ssize_t failslab_store(struct kmem_cache *s, const char *buf, + size_t length) +{ + s->flags &= ~SLAB_FAILSLAB; + if (buf[0] == '1') + s->flags |= SLAB_FAILSLAB; + return length; +} +SLAB_ATTR(failslab); +#endif + static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); @@ -4353,7 +4220,7 @@ static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) return -ENOMEM; for_each_online_cpu(cpu) { - unsigned x = get_cpu_slab(s, cpu)->stat[si]; + unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; data[cpu] = x; sum += x; @@ -4376,7 +4243,7 @@ static void clear_stat(struct kmem_cache *s, enum stat_item si) int cpu; for_each_online_cpu(cpu) - get_cpu_slab(s, cpu)->stat[si] = 0; + per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; } #define STAT_ATTR(si, text) \ @@ -4467,6 +4334,10 @@ static struct attribute *slab_attrs[] = { &deactivate_remote_frees_attr.attr, &order_fallback_attr.attr, #endif +#ifdef CONFIG_FAILSLAB + &failslab_attr.attr, +#endif + NULL }; |