diff options
Diffstat (limited to 'mm/slub.c')
| -rw-r--r-- | mm/slub.c | 112 |
1 files changed, 31 insertions, 81 deletions
diff --git a/mm/slub.c b/mm/slub.c index 44aa7847324ac..15505479c3abb 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -52,11 +52,11 @@ * and to synchronize major metadata changes to slab cache structures. * * The slab_lock is only used for debugging and on arches that do not - * have the ability to do a cmpxchg_double. It only protects the second - * double word in the page struct. Meaning + * have the ability to do a cmpxchg_double. It only protects: * A. page->freelist -> List of object free in a page - * B. page->counters -> Counters of objects - * C. page->frozen -> frozen state + * B. page->inuse -> Number of objects in use + * C. page->objects -> Number of objects in page + * D. page->frozen -> frozen state * * If a slab is frozen then it is exempt from list management. It is not * on any list. The processor that froze the slab is the one who can @@ -316,16 +316,16 @@ static inline unsigned int slab_index(void *p, struct kmem_cache *s, void *addr) return (p - addr) / s->size; } -static inline unsigned int order_objects(unsigned int order, unsigned int size, unsigned int reserved) +static inline unsigned int order_objects(unsigned int order, unsigned int size) { - return (((unsigned int)PAGE_SIZE << order) - reserved) / size; + return ((unsigned int)PAGE_SIZE << order) / size; } static inline struct kmem_cache_order_objects oo_make(unsigned int order, - unsigned int size, unsigned int reserved) + unsigned int size) { struct kmem_cache_order_objects x = { - (order << OO_SHIFT) + order_objects(order, size, reserved) + (order << OO_SHIFT) + order_objects(order, size) }; return x; @@ -356,21 +356,6 @@ static __always_inline void slab_unlock(struct page *page) __bit_spin_unlock(PG_locked, &page->flags); } -static inline void set_page_slub_counters(struct page *page, unsigned long counters_new) -{ - struct page tmp; - tmp.counters = counters_new; - /* - * page->counters can cover frozen/inuse/objects as well - * as page->_refcount. If we assign to ->counters directly - * we run the risk of losing updates to page->_refcount, so - * be careful and only assign to the fields we need. - */ - page->frozen = tmp.frozen; - page->inuse = tmp.inuse; - page->objects = tmp.objects; -} - /* Interrupts must be disabled (for the fallback code to work right) */ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page, void *freelist_old, unsigned long counters_old, @@ -392,7 +377,7 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page if (page->freelist == freelist_old && page->counters == counters_old) { page->freelist = freelist_new; - set_page_slub_counters(page, counters_new); + page->counters = counters_new; slab_unlock(page); return true; } @@ -431,7 +416,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page, if (page->freelist == freelist_old && page->counters == counters_old) { page->freelist = freelist_new; - set_page_slub_counters(page, counters_new); + page->counters = counters_new; slab_unlock(page); local_irq_restore(flags); return true; @@ -711,7 +696,7 @@ void object_err(struct kmem_cache *s, struct page *page, print_trailer(s, page, object); } -static void slab_err(struct kmem_cache *s, struct page *page, +static __printf(3, 4) void slab_err(struct kmem_cache *s, struct page *page, const char *fmt, ...) { va_list args; @@ -847,7 +832,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) return 1; start = page_address(page); - length = (PAGE_SIZE << compound_order(page)) - s->reserved; + length = PAGE_SIZE << compound_order(page); end = start + length; remainder = length % s->size; if (!remainder) @@ -936,7 +921,7 @@ static int check_slab(struct kmem_cache *s, struct page *page) return 0; } - maxobj = order_objects(compound_order(page), s->size, s->reserved); + maxobj = order_objects(compound_order(page), s->size); if (page->objects > maxobj) { slab_err(s, page, "objects %u > max %u", page->objects, maxobj); @@ -986,7 +971,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) nr++; } - max_objects = order_objects(compound_order(page), s->size, s->reserved); + max_objects = order_objects(compound_order(page), s->size); if (max_objects > MAX_OBJS_PER_PAGE) max_objects = MAX_OBJS_PER_PAGE; @@ -1694,24 +1679,16 @@ static void __free_slab(struct kmem_cache *s, struct page *page) __ClearPageSlabPfmemalloc(page); __ClearPageSlab(page); - page_mapcount_reset(page); + page->mapping = NULL; if (current->reclaim_state) current->reclaim_state->reclaimed_slab += pages; memcg_uncharge_slab(page, order, s); __free_pages(page, order); } -#define need_reserve_slab_rcu \ - (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head)) - static void rcu_free_slab(struct rcu_head *h) { - struct page *page; - - if (need_reserve_slab_rcu) - page = virt_to_head_page(h); - else - page = container_of((struct list_head *)h, struct page, lru); + struct page *page = container_of(h, struct page, rcu_head); __free_slab(page->slab_cache, page); } @@ -1719,19 +1696,7 @@ static void rcu_free_slab(struct rcu_head *h) static void free_slab(struct kmem_cache *s, struct page *page) { if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) { - struct rcu_head *head; - - if (need_reserve_slab_rcu) { - int order = compound_order(page); - int offset = (PAGE_SIZE << order) - s->reserved; - - VM_BUG_ON(s->reserved != sizeof(*head)); - head = page_address(page) + offset; - } else { - head = &page->rcu_head; - } - - call_rcu(head, rcu_free_slab); + call_rcu(&page->rcu_head, rcu_free_slab); } else __free_slab(s, page); } @@ -2444,6 +2409,8 @@ static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags, struct kmem_cache_cpu *c = *pc; struct page *page; + WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); + freelist = get_partial(s, flags, node, c); if (freelist) @@ -3226,21 +3193,21 @@ static unsigned int slub_min_objects; */ static inline unsigned int slab_order(unsigned int size, unsigned int min_objects, unsigned int max_order, - unsigned int fract_leftover, unsigned int reserved) + unsigned int fract_leftover) { unsigned int min_order = slub_min_order; unsigned int order; - if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE) + if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) return get_order(size * MAX_OBJS_PER_PAGE) - 1; - for (order = max(min_order, (unsigned int)get_order(min_objects * size + reserved)); + for (order = max(min_order, (unsigned int)get_order(min_objects * size)); order <= max_order; order++) { unsigned int slab_size = (unsigned int)PAGE_SIZE << order; unsigned int rem; - rem = (slab_size - reserved) % size; + rem = slab_size % size; if (rem <= slab_size / fract_leftover) break; @@ -3249,7 +3216,7 @@ static inline unsigned int slab_order(unsigned int size, return order; } -static inline int calculate_order(unsigned int size, unsigned int reserved) +static inline int calculate_order(unsigned int size) { unsigned int order; unsigned int min_objects; @@ -3266,7 +3233,7 @@ static inline int calculate_order(unsigned int size, unsigned int reserved) min_objects = slub_min_objects; if (!min_objects) min_objects = 4 * (fls(nr_cpu_ids) + 1); - max_objects = order_objects(slub_max_order, size, reserved); + max_objects = order_objects(slub_max_order, size); min_objects = min(min_objects, max_objects); while (min_objects > 1) { @@ -3275,7 +3242,7 @@ static inline int calculate_order(unsigned int size, unsigned int reserved) fraction = 16; while (fraction >= 4) { order = slab_order(size, min_objects, - slub_max_order, fraction, reserved); + slub_max_order, fraction); if (order <= slub_max_order) return order; fraction /= 2; @@ -3287,14 +3254,14 @@ static inline int calculate_order(unsigned int size, unsigned int reserved) * We were unable to place multiple objects in a slab. Now * lets see if we can place a single object there. */ - order = slab_order(size, 1, slub_max_order, 1, reserved); + order = slab_order(size, 1, slub_max_order, 1); if (order <= slub_max_order) return order; /* * Doh this slab cannot be placed using slub_max_order. */ - order = slab_order(size, 1, MAX_ORDER, 1, reserved); + order = slab_order(size, 1, MAX_ORDER, 1); if (order < MAX_ORDER) return order; return -ENOSYS; @@ -3562,7 +3529,7 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order) if (forced_order >= 0) order = forced_order; else - order = calculate_order(size, s->reserved); + order = calculate_order(size); if ((int)order < 0) return 0; @@ -3580,8 +3547,8 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order) /* * Determine the number of objects per slab */ - s->oo = oo_make(order, size, s->reserved); - s->min = oo_make(get_order(size), size, s->reserved); + s->oo = oo_make(order, size); + s->min = oo_make(get_order(size), size); if (oo_objects(s->oo) > oo_objects(s->max)) s->max = s->oo; @@ -3591,14 +3558,10 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order) static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) { s->flags = kmem_cache_flags(s->size, flags, s->name, s->ctor); - s->reserved = 0; #ifdef CONFIG_SLAB_FREELIST_HARDENED s->random = get_random_long(); #endif - if (need_reserve_slab_rcu && (s->flags & SLAB_TYPESAFE_BY_RCU)) - s->reserved = sizeof(struct rcu_head); - if (!calculate_sizes(s, -1)) goto error; if (disable_higher_order_debug) { @@ -4239,12 +4202,6 @@ void __init kmem_cache_init(void) SLAB_HWCACHE_ALIGN, 0, 0); kmem_cache = bootstrap(&boot_kmem_cache); - - /* - * Allocate kmem_cache_node properly from the kmem_cache slab. - * kmem_cache_node is separately allocated so no need to - * update any list pointers. - */ kmem_cache_node = bootstrap(&boot_kmem_cache_node); /* Now we can use the kmem_cache to allocate kmalloc slabs */ @@ -5117,12 +5074,6 @@ static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) } SLAB_ATTR_RO(destroy_by_rcu); -static ssize_t reserved_show(struct kmem_cache *s, char *buf) -{ - return sprintf(buf, "%u\n", s->reserved); -} -SLAB_ATTR_RO(reserved); - #ifdef CONFIG_SLUB_DEBUG static ssize_t slabs_show(struct kmem_cache *s, char *buf) { @@ -5435,7 +5386,6 @@ static struct attribute *slab_attrs[] = { &reclaim_account_attr.attr, &destroy_by_rcu_attr.attr, &shrink_attr.attr, - &reserved_attr.attr, &slabs_cpu_partial_attr.attr, #ifdef CONFIG_SLUB_DEBUG &total_objects_attr.attr, |