X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fslub.c;h=b7e2cd5d82dbd34577962e56d436dd94bd455b64;hb=4ad7a018cf4ac3cbad661c28c0f783ee0a6e3bf6;hp=38914bc64aca2cd58a4c40e35b1b8ef45b9e55d9;hpb=1b27d05b6e21249d2338be26dfcbe8f8d8ff8a5b;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/slub.c b/mm/slub.c index 38914bc..b7e2cd5 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -5,7 +5,7 @@ * The allocator synchronizes using per slab locks and only * uses a centralized lock to manage a pool of partial slabs. * - * (C) 2007 SGI, Christoph Lameter + * (C) 2007 SGI, Christoph Lameter */ #include @@ -19,8 +19,10 @@ #include #include #include +#include #include #include +#include /* * Lock order: @@ -100,44 +102,12 @@ * the fast path and disables lockless freelists. */ -#define FROZEN (1 << PG_active) - #ifdef CONFIG_SLUB_DEBUG -#define SLABDEBUG (1 << PG_error) +#define SLABDEBUG 1 #else #define SLABDEBUG 0 #endif -static inline int SlabFrozen(struct page *page) -{ - return page->flags & FROZEN; -} - -static inline void SetSlabFrozen(struct page *page) -{ - page->flags |= FROZEN; -} - -static inline void ClearSlabFrozen(struct page *page) -{ - page->flags &= ~FROZEN; -} - -static inline int SlabDebug(struct page *page) -{ - return page->flags & SLABDEBUG; -} - -static inline void SetSlabDebug(struct page *page) -{ - page->flags |= SLABDEBUG; -} - -static inline void ClearSlabDebug(struct page *page) -{ - page->flags &= ~SLABDEBUG; -} - /* * Issues still to be resolved: * @@ -149,25 +119,6 @@ static inline void ClearSlabDebug(struct page *page) /* Enable to test recovery from slab corruption on boot */ #undef SLUB_RESILIENCY_TEST -#if PAGE_SHIFT <= 12 - -/* - * Small page size. Make sure that we do not fragment memory - */ -#define DEFAULT_MAX_ORDER 1 -#define DEFAULT_MIN_OBJECTS 4 - -#else - -/* - * Large page machines are customarily able to handle larger - * page orders. - */ -#define DEFAULT_MAX_ORDER 2 -#define DEFAULT_MIN_OBJECTS 8 - -#endif - /* * Mininum number of partial slabs. These will be left on the partial * lists even if they are empty. kmem_cache_shrink may reclaim them. @@ -204,8 +155,6 @@ static inline void ClearSlabDebug(struct page *page) /* Internal SLUB flags */ #define __OBJECT_POISON 0x80000000 /* Poison object */ #define __SYSFS_ADD_DEFERRED 0x40000000 /* Not yet visible via sysfs */ -#define __KMALLOC_CACHE 0x20000000 /* objects freed using kfree */ -#define __PAGE_ALLOC_FALLBACK 0x10000000 /* Allow fallback to page alloc */ static int kmem_size = sizeof(struct kmem_cache); @@ -236,7 +185,7 @@ struct track { enum track_item { TRACK_ALLOC, TRACK_FREE }; -#if defined(CONFIG_SYSFS) && defined(CONFIG_SLUB_DEBUG) +#ifdef CONFIG_SLUB_DEBUG static int sysfs_slab_add(struct kmem_cache *); static int sysfs_slab_alias(struct kmem_cache *, const char *); static void sysfs_slab_remove(struct kmem_cache *); @@ -296,7 +245,7 @@ static inline int check_valid_pointer(struct kmem_cache *s, return 1; base = page_address(page); - if (object < base || object >= base + s->objects * s->size || + if (object < base || object >= base + page->objects * s->size || (object - base) % s->size) { return 0; } @@ -322,8 +271,8 @@ static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) } /* Loop over all objects in a slab */ -#define for_each_object(__p, __s, __addr) \ - for (__p = (__addr); __p < (__addr) + (__s)->objects * (__s)->size;\ +#define for_each_object(__p, __s, __addr, __objects) \ + for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\ __p += (__s)->size) /* Scan freelist */ @@ -336,6 +285,26 @@ static inline int slab_index(void *p, struct kmem_cache *s, void *addr) return (p - addr) / s->size; } +static inline struct kmem_cache_order_objects oo_make(int order, + unsigned long size) +{ + struct kmem_cache_order_objects x = { + (order << 16) + (PAGE_SIZE << order) / size + }; + + return x; +} + +static inline int oo_order(struct kmem_cache_order_objects x) +{ + return x.x >> 16; +} + +static inline int oo_objects(struct kmem_cache_order_objects x) +{ + return x.x & ((1 << 16) - 1); +} + #ifdef CONFIG_SLUB_DEBUG /* * Debug settings: @@ -410,7 +379,7 @@ static void set_track(struct kmem_cache *s, void *object, if (addr) { p->addr = addr; p->cpu = smp_processor_id(); - p->pid = current ? current->pid : -1; + p->pid = current->pid; p->when = jiffies; } else memset(p, 0, sizeof(struct track)); @@ -430,9 +399,8 @@ static void print_track(const char *s, struct track *t) if (!t->addr) return; - printk(KERN_ERR "INFO: %s in ", s); - __print_symbol("%s", (unsigned long)t->addr); - printk(" age=%lu cpu=%u pid=%d\n", jiffies - t->when, t->cpu, t->pid); + printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n", + s, t->addr, jiffies - t->when, t->cpu, t->pid); } static void print_tracking(struct kmem_cache *s, void *object) @@ -446,8 +414,8 @@ static void print_tracking(struct kmem_cache *s, void *object) static void print_page_info(struct page *page) { - printk(KERN_ERR "INFO: Slab 0x%p used=%u fp=0x%p flags=0x%04lx\n", - page, page->inuse, page->freelist, page->flags); + printk(KERN_ERR "INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n", + page, page->objects, page->inuse, page->freelist, page->flags); } @@ -492,7 +460,7 @@ static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) if (p > addr + 16) print_section("Bytes b4", p - 16, 16); - print_section("Object", p, min(s->objsize, 128)); + print_section("Object", p, min_t(unsigned long, s->objsize, PAGE_SIZE)); if (s->flags & SLAB_RED_ZONE) print_section("Redzone", p + s->objsize, @@ -647,6 +615,7 @@ static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) p + off, POISON_INUSE, s->size - off); } +/* Check the pad bytes at the end of a slab page */ static int slab_pad_check(struct kmem_cache *s, struct page *page) { u8 *start; @@ -659,20 +628,20 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) return 1; start = page_address(page); - end = start + (PAGE_SIZE << s->order); - length = s->objects * s->size; - remainder = end - (start + length); + length = (PAGE_SIZE << compound_order(page)); + end = start + length; + remainder = length % s->size; if (!remainder) return 1; - fault = check_bytes(start + length, POISON_INUSE, remainder); + fault = check_bytes(end - remainder, POISON_INUSE, remainder); if (!fault) return 1; while (end > fault && end[-1] == POISON_INUSE) end--; slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); - print_section("Padding", start, length); + print_section("Padding", end - remainder, remainder); restore_bytes(s, "slab padding", POISON_INUSE, start, end); return 0; @@ -734,15 +703,24 @@ static int check_object(struct kmem_cache *s, struct page *page, static int check_slab(struct kmem_cache *s, struct page *page) { + int maxobj; + VM_BUG_ON(!irqs_disabled()); if (!PageSlab(page)) { slab_err(s, page, "Not a valid slab page"); return 0; } - if (page->inuse > s->objects) { + + maxobj = (PAGE_SIZE << compound_order(page)) / s->size; + if (page->objects > maxobj) { + slab_err(s, page, "objects %u > max %u", + s->name, page->objects, maxobj); + return 0; + } + if (page->inuse > page->objects) { slab_err(s, page, "inuse %u > max %u", - s->name, page->inuse, s->objects); + s->name, page->inuse, page->objects); return 0; } /* Slab_pad_check fixes things up after itself */ @@ -759,8 +737,9 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) int nr = 0; void *fp = page->freelist; void *object = NULL; + unsigned long max_objects; - while (fp && nr <= s->objects) { + while (fp && nr <= page->objects) { if (fp == search) return 1; if (!check_valid_pointer(s, page, fp)) { @@ -772,7 +751,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) } else { slab_err(s, page, "Freepointer corrupt"); page->freelist = NULL; - page->inuse = s->objects; + page->inuse = page->objects; slab_fix(s, "Freelist cleared"); return 0; } @@ -783,16 +762,27 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) nr++; } - if (page->inuse != s->objects - nr) { + max_objects = (PAGE_SIZE << compound_order(page)) / s->size; + if (max_objects > 65535) + max_objects = 65535; + + if (page->objects != max_objects) { + slab_err(s, page, "Wrong number of objects. Found %d but " + "should be %d", page->objects, max_objects); + page->objects = max_objects; + slab_fix(s, "Number of objects adjusted."); + } + if (page->inuse != page->objects - nr) { slab_err(s, page, "Wrong object count. Counter is %d but " - "counted were %d", page->inuse, s->objects - nr); - page->inuse = s->objects - nr; + "counted were %d", page->inuse, page->objects - nr); + page->inuse = page->objects - nr; slab_fix(s, "Object count adjusted."); } return search == NULL; } -static void trace(struct kmem_cache *s, struct page *page, void *object, int alloc) +static void trace(struct kmem_cache *s, struct page *page, void *object, + int alloc) { if (s->flags & SLAB_TRACE) { printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n", @@ -840,7 +830,7 @@ static inline unsigned long slabs_node(struct kmem_cache *s, int node) return atomic_long_read(&n->nr_slabs); } -static inline void inc_slabs_node(struct kmem_cache *s, int node) +static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) { struct kmem_cache_node *n = get_node(s, node); @@ -850,14 +840,17 @@ static inline void inc_slabs_node(struct kmem_cache *s, int node) * dilemma by deferring the increment of the count during * bootstrap (see early_kmem_cache_node_alloc). */ - if (!NUMA_BUILD || n) + if (!NUMA_BUILD || n) { atomic_long_inc(&n->nr_slabs); + atomic_long_add(objects, &n->total_objects); + } } -static inline void dec_slabs_node(struct kmem_cache *s, int node) +static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) { struct kmem_cache_node *n = get_node(s, node); atomic_long_dec(&n->nr_slabs); + atomic_long_sub(objects, &n->total_objects); } /* Object debug checks for alloc/free paths */ @@ -905,7 +898,7 @@ bad: * as used avoids touching the remaining objects. */ slab_fix(s, "Marking all objects used"); - page->inuse = s->objects; + page->inuse = page->objects; page->freelist = NULL; } return 0; @@ -946,7 +939,7 @@ static int free_debug_processing(struct kmem_cache *s, struct page *page, } /* Special debug activities for freeing objects */ - if (!SlabFrozen(page) && !page->freelist) + if (!PageSlubFrozen(page) && !page->freelist) remove_full(s, page); if (s->flags & SLAB_STORE_USER) set_track(s, object, TRACK_FREE, addr); @@ -1019,7 +1012,7 @@ __setup("slub_debug", setup_slub_debug); static unsigned long kmem_cache_flags(unsigned long objsize, unsigned long flags, const char *name, - void (*ctor)(struct kmem_cache *, void *)) + void (*ctor)(void *)) { /* * Enable debugging if selected on the kernel commandline. @@ -1047,7 +1040,7 @@ static inline int check_object(struct kmem_cache *s, struct page *page, static inline void add_full(struct kmem_cache_node *n, struct page *page) {} static inline unsigned long kmem_cache_flags(unsigned long objsize, unsigned long flags, const char *name, - void (*ctor)(struct kmem_cache *, void *)) + void (*ctor)(void *)) { return flags; } @@ -1055,31 +1048,52 @@ static inline unsigned long kmem_cache_flags(unsigned long objsize, static inline unsigned long slabs_node(struct kmem_cache *s, int node) { return 0; } -static inline void inc_slabs_node(struct kmem_cache *s, int node) {} -static inline void dec_slabs_node(struct kmem_cache *s, int node) {} +static inline void inc_slabs_node(struct kmem_cache *s, int node, + int objects) {} +static inline void dec_slabs_node(struct kmem_cache *s, int node, + int objects) {} #endif + /* * Slab allocation and freeing */ +static inline struct page *alloc_slab_page(gfp_t flags, int node, + struct kmem_cache_order_objects oo) +{ + int order = oo_order(oo); + + if (node == -1) + return alloc_pages(flags, order); + else + return alloc_pages_node(node, flags, order); +} + static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) { struct page *page; - int pages = 1 << s->order; + struct kmem_cache_order_objects oo = s->oo; flags |= s->allocflags; - if (node == -1) - page = alloc_pages(flags, s->order); - else - page = alloc_pages_node(node, flags, s->order); - - if (!page) - return NULL; + page = alloc_slab_page(flags | __GFP_NOWARN | __GFP_NORETRY, node, + oo); + if (unlikely(!page)) { + oo = s->min; + /* + * Allocation may have failed due to fragmentation. + * Try a lower order alloc if possible + */ + page = alloc_slab_page(flags, node, oo); + if (!page) + return NULL; + stat(get_cpu_slab(s, raw_smp_processor_id()), ORDER_FALLBACK); + } + page->objects = oo_objects(oo); mod_zone_page_state(page_zone(page), (s->flags & SLAB_RECLAIM_ACCOUNT) ? NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, - pages); + 1 << oo_order(oo)); return page; } @@ -1089,7 +1103,7 @@ static void setup_object(struct kmem_cache *s, struct page *page, { setup_object_debug(s, page, object); if (unlikely(s->ctor)) - s->ctor(s, object); + s->ctor(object); } static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) @@ -1106,20 +1120,20 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) if (!page) goto out; - inc_slabs_node(s, page_to_nid(page)); + inc_slabs_node(s, page_to_nid(page), page->objects); page->slab = s; page->flags |= 1 << PG_slab; if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | SLAB_TRACE)) - SetSlabDebug(page); + __SetPageSlubDebug(page); start = page_address(page); if (unlikely(s->flags & SLAB_POISON)) - memset(start, POISON_INUSE, PAGE_SIZE << s->order); + memset(start, POISON_INUSE, PAGE_SIZE << compound_order(page)); last = start; - for_each_object(p, s, start) { + for_each_object(p, s, start, page->objects) { setup_object(s, page, last); set_freepointer(s, last, p); last = p; @@ -1135,15 +1149,17 @@ out: static void __free_slab(struct kmem_cache *s, struct page *page) { - int pages = 1 << s->order; + int order = compound_order(page); + int pages = 1 << order; - if (unlikely(SlabDebug(page))) { + if (unlikely(SLABDEBUG && PageSlubDebug(page))) { void *p; slab_pad_check(s, page); - for_each_object(p, s, page_address(page)) + for_each_object(p, s, page_address(page), + page->objects) check_object(s, page, p, 0); - ClearSlabDebug(page); + __ClearPageSlubDebug(page); } mod_zone_page_state(page_zone(page), @@ -1153,7 +1169,7 @@ static void __free_slab(struct kmem_cache *s, struct page *page) __ClearPageSlab(page); reset_page_mapcount(page); - __free_pages(page, s->order); + __free_pages(page, order); } static void rcu_free_slab(struct rcu_head *h) @@ -1179,7 +1195,7 @@ static void free_slab(struct kmem_cache *s, struct page *page) static void discard_slab(struct kmem_cache *s, struct page *page) { - dec_slabs_node(s, page_to_nid(page)); + dec_slabs_node(s, page_to_nid(page), page->objects); free_slab(s, page); } @@ -1219,8 +1235,7 @@ static void add_partial(struct kmem_cache_node *n, spin_unlock(&n->list_lock); } -static void remove_partial(struct kmem_cache *s, - struct page *page) +static void remove_partial(struct kmem_cache *s, struct page *page) { struct kmem_cache_node *n = get_node(s, page_to_nid(page)); @@ -1235,12 +1250,13 @@ static void remove_partial(struct kmem_cache *s, * * Must hold list_lock. */ -static inline int lock_and_freeze_slab(struct kmem_cache_node *n, struct page *page) +static inline int lock_and_freeze_slab(struct kmem_cache_node *n, + struct page *page) { if (slab_trylock(page)) { list_del(&page->lru); n->nr_partial--; - SetSlabFrozen(page); + __SetPageSlubFrozen(page); return 1; } return 0; @@ -1350,7 +1366,7 @@ 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()); - ClearSlabFrozen(page); + __ClearPageSlubFrozen(page); if (page->inuse) { if (page->freelist) { @@ -1358,7 +1374,8 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) stat(c, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); } else { stat(c, DEACTIVATE_FULL); - if (SlabDebug(page) && (s->flags & SLAB_STORE_USER)) + if (SLABDEBUG && PageSlubDebug(page) && + (s->flags & SLAB_STORE_USER)) add_full(n, page); } slab_unlock(page); @@ -1372,8 +1389,8 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) * so that the others get filled first. That way the * size of the partial list stays small. * - * kmem_cache_shrink can reclaim any empty slabs from the - * partial list. + * kmem_cache_shrink can reclaim any empty slabs from + * the partial list. */ add_partial(n, page, 1); slab_unlock(page); @@ -1447,15 +1464,7 @@ static void flush_cpu_slab(void *d) static void flush_all(struct kmem_cache *s) { -#ifdef CONFIG_SMP - on_each_cpu(flush_cpu_slab, s, 1, 1); -#else - unsigned long flags; - - local_irq_save(flags); - flush_cpu_slab(s); - local_irq_restore(flags); -#endif + on_each_cpu(flush_cpu_slab, s, 1); } /* @@ -1511,11 +1520,11 @@ load_freelist: object = c->page->freelist; if (unlikely(!object)) goto another_slab; - if (unlikely(SlabDebug(c->page))) + if (unlikely(SLABDEBUG && PageSlubDebug(c->page))) goto debug; c->freelist = object[c->offset]; - c->page->inuse = s->objects; + c->page->inuse = c->page->objects; c->page->freelist = NULL; c->node = page_to_nid(c->page); unlock_out: @@ -1548,31 +1557,10 @@ new_slab: if (c->page) flush_slab(s, c); slab_lock(new); - SetSlabFrozen(new); + __SetPageSlubFrozen(new); c->page = new; goto load_freelist; } - - /* - * No memory available. - * - * If the slab uses higher order allocs but the object is - * smaller than a page size then we can fallback in emergencies - * to the page allocator via kmalloc_large. The page allocator may - * have failed to obtain a higher order page and we can try to - * allocate a single page if the object fits into a single page. - * That is only possible if certain conditions are met that are being - * checked when a slab is created. - */ - if (!(gfpflags & __GFP_NORETRY) && - (s->flags & __PAGE_ALLOC_FALLBACK)) { - if (gfpflags & __GFP_WAIT) - local_irq_enable(); - object = kmalloc_large(s->objsize, gfpflags); - if (gfpflags & __GFP_WAIT) - local_irq_disable(); - return object; - } return NULL; debug: if (!alloc_debug_processing(s, c->page, object, addr)) @@ -1600,9 +1588,11 @@ static __always_inline void *slab_alloc(struct kmem_cache *s, void **object; struct kmem_cache_cpu *c; unsigned long flags; + unsigned int objsize; local_irq_save(flags); c = get_cpu_slab(s, smp_processor_id()); + objsize = c->objsize; if (unlikely(!c->freelist || !node_match(c, node))) object = __slab_alloc(s, gfpflags, node, addr, c); @@ -1615,7 +1605,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s, local_irq_restore(flags); if (unlikely((gfpflags & __GFP_ZERO) && object)) - memset(object, 0, c->objsize); + memset(object, 0, objsize); return object; } @@ -1653,7 +1643,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page, stat(c, FREE_SLOWPATH); slab_lock(page); - if (unlikely(SlabDebug(page))) + if (unlikely(SLABDEBUG && PageSlubDebug(page))) goto debug; checks_ok: @@ -1661,7 +1651,7 @@ checks_ok: page->freelist = object; page->inuse--; - if (unlikely(SlabFrozen(page))) { + if (unlikely(PageSlubFrozen(page))) { stat(c, FREE_FROZEN); goto out_unlock; } @@ -1722,6 +1712,8 @@ static __always_inline void slab_free(struct kmem_cache *s, local_irq_save(flags); c = get_cpu_slab(s, smp_processor_id()); debug_check_no_locks_freed(object, c->objsize); + if (!(s->flags & SLAB_DEBUG_OBJECTS)) + debug_check_no_obj_freed(object, s->objsize); if (likely(page == c->page && c->node >= 0)) { object[c->offset] = c->freelist; c->freelist = object; @@ -1773,8 +1765,8 @@ static struct page *get_object_page(const void *x) * take the list_lock. */ static int slub_min_order; -static int slub_max_order = DEFAULT_MAX_ORDER; -static int slub_min_objects = DEFAULT_MIN_OBJECTS; +static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER; +static int slub_min_objects; /* * Merge control. If this is set then no merging of slab caches will occur. @@ -1789,7 +1781,7 @@ static int slub_nomerge; * system components. Generally order 0 allocations should be preferred since * order 0 does not cause fragmentation in the page allocator. Larger objects * be problematic to put into order 0 slabs because there may be too much - * unused space left. We go to a higher order if more than 1/8th of the slab + * unused space left. We go to a higher order if more than 1/16th of the slab * would be wasted. * * In order to reach satisfactory performance we must ensure that a minimum @@ -1814,6 +1806,9 @@ static inline int slab_order(int size, int min_objects, int rem; int min_order = slub_min_order; + if ((PAGE_SIZE << min_order) / size > 65535) + return get_order(size * 65535) - 1; + for (order = max(min_order, fls(min_objects * size - 1) - PAGE_SHIFT); order <= max_order; order++) { @@ -1848,8 +1843,10 @@ static inline int calculate_order(int size) * we reduce the minimum objects required in a slab. */ min_objects = slub_min_objects; + if (!min_objects) + min_objects = 4 * (fls(nr_cpu_ids) + 1); while (min_objects > 1) { - fraction = 8; + fraction = 16; while (fraction >= 4) { order = slab_order(size, min_objects, slub_max_order, fraction); @@ -2091,7 +2088,7 @@ static struct kmem_cache_node *early_kmem_cache_node_alloc(gfp_t gfpflags, init_tracking(kmalloc_caches, n); #endif init_kmem_cache_node(n); - inc_slabs_node(kmalloc_caches, node); + inc_slabs_node(kmalloc_caches, node, page->objects); /* * lockdep requires consistent irq usage for each lock @@ -2167,11 +2164,12 @@ static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) * calculate_sizes() determines the order and the distribution of data within * a slab object. */ -static int calculate_sizes(struct kmem_cache *s) +static int calculate_sizes(struct kmem_cache *s, int forced_order) { unsigned long flags = s->flags; unsigned long size = s->objsize; unsigned long align = s->align; + int order; /* * Round up object size to the next word boundary. We can only @@ -2255,26 +2253,16 @@ static int calculate_sizes(struct kmem_cache *s) */ size = ALIGN(size, align); s->size = size; + if (forced_order >= 0) + order = forced_order; + else + order = calculate_order(size); - if ((flags & __KMALLOC_CACHE) && - PAGE_SIZE / size < slub_min_objects) { - /* - * Kmalloc cache that would not have enough objects in - * an order 0 page. Kmalloc slabs can fallback to - * page allocator order 0 allocs so take a reasonably large - * order that will allows us a good number of objects. - */ - s->order = max(slub_max_order, PAGE_ALLOC_COSTLY_ORDER); - s->flags |= __PAGE_ALLOC_FALLBACK; - s->allocflags |= __GFP_NOWARN; - } else - s->order = calculate_order(size); - - if (s->order < 0) + if (order < 0) return 0; s->allocflags = 0; - if (s->order) + if (order) s->allocflags |= __GFP_COMP; if (s->flags & SLAB_CACHE_DMA) @@ -2286,16 +2274,19 @@ static int calculate_sizes(struct kmem_cache *s) /* * Determine the number of objects per slab */ - s->objects = (PAGE_SIZE << s->order) / size; + 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; - return !!s->objects; + return !!oo_objects(s->oo); } static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, const char *name, size_t size, size_t align, unsigned long flags, - void (*ctor)(struct kmem_cache *, void *)) + void (*ctor)(void *)) { memset(s, 0, kmem_size); s->name = name; @@ -2304,7 +2295,7 @@ static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, s->align = align; s->flags = kmem_cache_flags(size, flags, name, ctor); - if (!calculate_sizes(s)) + if (!calculate_sizes(s, -1)) goto error; s->refcount = 1; @@ -2321,7 +2312,7 @@ error: if (flags & SLAB_PANIC) panic("Cannot create slab %s size=%lu realsize=%u " "order=%u offset=%u flags=%lx\n", - s->name, (unsigned long)size, s->size, s->order, + s->name, (unsigned long)size, s->size, oo_order(s->oo), s->offset, flags); return 0; } @@ -2367,26 +2358,52 @@ const char *kmem_cache_name(struct kmem_cache *s) } EXPORT_SYMBOL(kmem_cache_name); +static void list_slab_objects(struct kmem_cache *s, struct page *page, + const char *text) +{ +#ifdef CONFIG_SLUB_DEBUG + void *addr = page_address(page); + void *p; + DECLARE_BITMAP(map, page->objects); + + bitmap_zero(map, page->objects); + slab_err(s, page, "%s", text); + slab_lock(page); + for_each_free_object(p, s, page->freelist) + set_bit(slab_index(p, s, addr), map); + + for_each_object(p, s, addr, page->objects) { + + if (!test_bit(slab_index(p, s, addr), map)) { + printk(KERN_ERR "INFO: Object 0x%p @offset=%tu\n", + p, p - addr); + print_tracking(s, p); + } + } + slab_unlock(page); +#endif +} + /* - * Attempt to free all slabs on a node. Return the number of slabs we - * were unable to free. + * Attempt to free all partial slabs on a node. */ -static int free_list(struct kmem_cache *s, struct kmem_cache_node *n, - struct list_head *list) +static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) { - int slabs_inuse = 0; unsigned long flags; struct page *page, *h; spin_lock_irqsave(&n->list_lock, flags); - list_for_each_entry_safe(page, h, list, lru) + list_for_each_entry_safe(page, h, &n->partial, lru) { if (!page->inuse) { list_del(&page->lru); discard_slab(s, page); - } else - slabs_inuse++; + n->nr_partial--; + } else { + list_slab_objects(s, page, + "Objects remaining on kmem_cache_close()"); + } + } spin_unlock_irqrestore(&n->list_lock, flags); - return slabs_inuse; } /* @@ -2403,8 +2420,8 @@ static inline int kmem_cache_close(struct kmem_cache *s) for_each_node_state(node, N_NORMAL_MEMORY) { struct kmem_cache_node *n = get_node(s, node); - n->nr_partial -= free_list(s, n, &n->partial); - if (slabs_node(s, node)) + free_partial(s, n); + if (n->nr_partial || slabs_node(s, node)) return 1; } free_kmem_cache_nodes(s); @@ -2422,8 +2439,11 @@ void kmem_cache_destroy(struct kmem_cache *s) if (!s->refcount) { list_del(&s->list); up_write(&slub_lock); - if (kmem_cache_close(s)) - WARN_ON(1); + if (kmem_cache_close(s)) { + printk(KERN_ERR "SLUB %s: %s called for cache that " + "still has objects.\n", s->name, __func__); + dump_stack(); + } sysfs_slab_remove(s); } else up_write(&slub_lock); @@ -2482,7 +2502,7 @@ static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s, down_write(&slub_lock); if (!kmem_cache_open(s, gfp_flags, name, size, ARCH_KMALLOC_MINALIGN, - flags | __KMALLOC_CACHE, NULL)) + flags, NULL)) goto panic; list_add(&s->list, &slab_caches); @@ -2668,9 +2688,10 @@ size_t ksize(const void *object) page = virt_to_head_page(object); - if (unlikely(!PageSlab(page))) + if (unlikely(!PageSlab(page))) { + WARN_ON(!PageCompound(page)); return PAGE_SIZE << compound_order(page); - + } s = page->slab; #ifdef CONFIG_SLUB_DEBUG @@ -2706,6 +2727,7 @@ void kfree(const void *x) page = virt_to_head_page(x); if (unlikely(!PageSlab(page))) { + BUG_ON(!PageCompound(page)); put_page(page); return; } @@ -2730,8 +2752,9 @@ int kmem_cache_shrink(struct kmem_cache *s) struct kmem_cache_node *n; struct page *page; struct page *t; + int objects = oo_objects(s->max); struct list_head *slabs_by_inuse = - kmalloc(sizeof(struct list_head) * s->objects, GFP_KERNEL); + kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL); unsigned long flags; if (!slabs_by_inuse) @@ -2744,7 +2767,7 @@ int kmem_cache_shrink(struct kmem_cache *s) if (!n->nr_partial) continue; - for (i = 0; i < s->objects; i++) + for (i = 0; i < objects; i++) INIT_LIST_HEAD(slabs_by_inuse + i); spin_lock_irqsave(&n->list_lock, flags); @@ -2776,7 +2799,7 @@ int kmem_cache_shrink(struct kmem_cache *s) * Rebuild the partial list with the slabs filled up most * first and the least used slabs at the end. */ - for (i = s->objects - 1; i >= 0; i--) + for (i = objects - 1; i >= 0; i--) list_splice(slabs_by_inuse + i, n->partial.prev); spin_unlock_irqrestore(&n->list_lock, flags); @@ -2851,7 +2874,7 @@ static int slab_mem_going_online_callback(void *arg) return 0; /* - * We are bringing a node online. No memory is availabe yet. We must + * We are bringing a node online. No memory is available yet. We must * allocate a kmem_cache_node structure in order to bring the node * online. */ @@ -2924,7 +2947,7 @@ void __init kmem_cache_init(void) kmalloc_caches[0].refcount = -1; caches++; - hotplug_memory_notifier(slab_memory_callback, 1); + hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); #endif /* Able to allocate the per node structures */ @@ -2935,8 +2958,6 @@ void __init kmem_cache_init(void) create_kmalloc_cache(&kmalloc_caches[1], "kmalloc-96", 96, GFP_KERNEL); caches++; - } - if (KMALLOC_MIN_SIZE <= 128) { create_kmalloc_cache(&kmalloc_caches[2], "kmalloc-192", 192, GFP_KERNEL); caches++; @@ -2966,6 +2987,16 @@ void __init kmem_cache_init(void) for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) size_index[(i - 1) / 8] = KMALLOC_SHIFT_LOW; + if (KMALLOC_MIN_SIZE == 128) { + /* + * The 192 byte sized cache is not used if the alignment + * is 128 byte. Redirect kmalloc to use the 256 byte cache + * instead. + */ + for (i = 128 + 8; i <= 192; i += 8) + size_index[(i - 1) / 8] = 8; + } + slab_state = UP; /* Provide the correct kmalloc names now that the caches are up */ @@ -2997,9 +3028,6 @@ static int slab_unmergeable(struct kmem_cache *s) if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE)) return 1; - if ((s->flags & __PAGE_ALLOC_FALLBACK)) - return 1; - if (s->ctor) return 1; @@ -3014,7 +3042,7 @@ static int slab_unmergeable(struct kmem_cache *s) static struct kmem_cache *find_mergeable(size_t size, size_t align, unsigned long flags, const char *name, - void (*ctor)(struct kmem_cache *, void *)) + void (*ctor)(void *)) { struct kmem_cache *s; @@ -3054,8 +3082,7 @@ static struct kmem_cache *find_mergeable(size_t size, } struct kmem_cache *kmem_cache_create(const char *name, size_t size, - size_t align, unsigned long flags, - void (*ctor)(struct kmem_cache *, void *)) + size_t align, unsigned long flags, void (*ctor)(void *)) { struct kmem_cache *s; @@ -3191,8 +3218,9 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, return slab_alloc(s, gfpflags, node, caller); } -#if (defined(CONFIG_SYSFS) && defined(CONFIG_SLUB_DEBUG)) || defined(CONFIG_SLABINFO) -static unsigned long count_partial(struct kmem_cache_node *n) +#ifdef CONFIG_SLUB_DEBUG +static unsigned long count_partial(struct kmem_cache_node *n, + int (*get_count)(struct page *)) { unsigned long flags; unsigned long x = 0; @@ -3200,13 +3228,26 @@ static unsigned long count_partial(struct kmem_cache_node *n) spin_lock_irqsave(&n->list_lock, flags); list_for_each_entry(page, &n->partial, lru) - x += page->inuse; + x += get_count(page); spin_unlock_irqrestore(&n->list_lock, flags); return x; } -#endif -#if defined(CONFIG_SYSFS) && defined(CONFIG_SLUB_DEBUG) +static int count_inuse(struct page *page) +{ + return page->inuse; +} + +static int count_total(struct page *page) +{ + return page->objects; +} + +static int count_free(struct page *page) +{ + return page->objects - page->inuse; +} + static int validate_slab(struct kmem_cache *s, struct page *page, unsigned long *map) { @@ -3218,7 +3259,7 @@ static int validate_slab(struct kmem_cache *s, struct page *page, return 0; /* Now we know that a valid freelist exists */ - bitmap_zero(map, s->objects); + bitmap_zero(map, page->objects); for_each_free_object(p, s, page->freelist) { set_bit(slab_index(p, s, addr), map); @@ -3226,7 +3267,7 @@ static int validate_slab(struct kmem_cache *s, struct page *page, return 0; } - for_each_object(p, s, addr) + for_each_object(p, s, addr, page->objects) if (!test_bit(slab_index(p, s, addr), map)) if (!check_object(s, page, p, 1)) return 0; @@ -3244,12 +3285,12 @@ static void validate_slab_slab(struct kmem_cache *s, struct page *page, s->name, page); if (s->flags & DEBUG_DEFAULT_FLAGS) { - if (!SlabDebug(page)) - printk(KERN_ERR "SLUB %s: SlabDebug not set " + if (!PageSlubDebug(page)) + printk(KERN_ERR "SLUB %s: SlubDebug not set " "on slab 0x%p\n", s->name, page); } else { - if (SlabDebug(page)) - printk(KERN_ERR "SLUB %s: SlabDebug set on " + if (PageSlubDebug(page)) + printk(KERN_ERR "SLUB %s: SlubDebug set on " "slab 0x%p\n", s->name, page); } } @@ -3292,7 +3333,7 @@ static long validate_slab_cache(struct kmem_cache *s) { int node; unsigned long count = 0; - unsigned long *map = kmalloc(BITS_TO_LONGS(s->objects) * + unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) * sizeof(unsigned long), GFP_KERNEL); if (!map) @@ -3495,14 +3536,14 @@ static void process_slab(struct loc_track *t, struct kmem_cache *s, struct page *page, enum track_item alloc) { void *addr = page_address(page); - DECLARE_BITMAP(map, s->objects); + DECLARE_BITMAP(map, page->objects); void *p; - bitmap_zero(map, s->objects); + bitmap_zero(map, page->objects); for_each_free_object(p, s, page->freelist) set_bit(slab_index(p, s, addr), map); - for_each_object(p, s, addr) + for_each_object(p, s, addr, page->objects) if (!test_bit(slab_index(p, s, addr), map)) add_location(t, s, get_track(s, p, alloc)); } @@ -3551,12 +3592,10 @@ static int list_locations(struct kmem_cache *s, char *buf, len += sprintf(buf + len, ""); if (l->sum_time != l->min_time) { - unsigned long remainder; - len += sprintf(buf + len, " age=%ld/%ld/%ld", - l->min_time, - div_long_long_rem(l->sum_time, l->count, &remainder), - l->max_time); + l->min_time, + (long)div_u64(l->sum_time, l->count), + l->max_time); } else len += sprintf(buf + len, " age=%ld", l->min_time); @@ -3592,22 +3631,23 @@ static int list_locations(struct kmem_cache *s, char *buf, } enum slab_stat_type { - SL_FULL, - SL_PARTIAL, - SL_CPU, - SL_OBJECTS + SL_ALL, /* All slabs */ + SL_PARTIAL, /* Only partially allocated slabs */ + SL_CPU, /* Only slabs used for cpu caches */ + SL_OBJECTS, /* Determine allocated objects not slabs */ + SL_TOTAL /* Determine object capacity not slabs */ }; -#define SO_FULL (1 << SL_FULL) +#define SO_ALL (1 << SL_ALL) #define SO_PARTIAL (1 << SL_PARTIAL) #define SO_CPU (1 << SL_CPU) #define SO_OBJECTS (1 << SL_OBJECTS) +#define SO_TOTAL (1 << SL_TOTAL) static ssize_t show_slab_objects(struct kmem_cache *s, char *buf, unsigned long flags) { unsigned long total = 0; - int cpu; int node; int x; unsigned long *nodes; @@ -3618,56 +3658,60 @@ static ssize_t show_slab_objects(struct kmem_cache *s, return -ENOMEM; per_cpu = nodes + nr_node_ids; - for_each_possible_cpu(cpu) { - struct page *page; - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); + if (flags & SO_CPU) { + int cpu; - if (!c) - continue; + for_each_possible_cpu(cpu) { + struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); - page = c->page; - node = c->node; - if (node < 0) - continue; - if (page) { - if (flags & SO_CPU) { - if (flags & SO_OBJECTS) - x = page->inuse; + if (!c || c->node < 0) + continue; + + if (c->page) { + if (flags & SO_TOTAL) + x = c->page->objects; + else if (flags & SO_OBJECTS) + x = c->page->inuse; else x = 1; + total += x; - nodes[node] += x; + nodes[c->node] += x; } - per_cpu[node]++; + per_cpu[c->node]++; } } - for_each_node_state(node, N_NORMAL_MEMORY) { - struct kmem_cache_node *n = get_node(s, node); + if (flags & SO_ALL) { + for_each_node_state(node, N_NORMAL_MEMORY) { + struct kmem_cache_node *n = get_node(s, node); + + if (flags & SO_TOTAL) + x = atomic_long_read(&n->total_objects); + else if (flags & SO_OBJECTS) + x = atomic_long_read(&n->total_objects) - + count_partial(n, count_free); - if (flags & SO_PARTIAL) { - if (flags & SO_OBJECTS) - x = count_partial(n); else - x = n->nr_partial; + x = atomic_long_read(&n->nr_slabs); total += x; nodes[node] += x; } - if (flags & SO_FULL) { - int full_slabs = atomic_long_read(&n->nr_slabs) - - per_cpu[node] - - n->nr_partial; + } else if (flags & SO_PARTIAL) { + for_each_node_state(node, N_NORMAL_MEMORY) { + struct kmem_cache_node *n = get_node(s, node); - if (flags & SO_OBJECTS) - x = full_slabs * s->objects; + if (flags & SO_TOTAL) + x = count_partial(n, count_total); + else if (flags & SO_OBJECTS) + x = count_partial(n, count_inuse); else - x = full_slabs; + x = n->nr_partial; total += x; nodes[node] += x; } } - x = sprintf(buf, "%lu", total); #ifdef CONFIG_NUMA for_each_node_state(node, N_NORMAL_MEMORY) @@ -3682,14 +3726,6 @@ static ssize_t show_slab_objects(struct kmem_cache *s, static int any_slab_objects(struct kmem_cache *s) { int node; - int cpu; - - for_each_possible_cpu(cpu) { - struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); - - if (c && c->page) - return 1; - } for_each_online_node(node) { struct kmem_cache_node *n = get_node(s, node); @@ -3697,7 +3733,7 @@ static int any_slab_objects(struct kmem_cache *s) if (!n) continue; - if (n->nr_partial || atomic_long_read(&n->nr_slabs)) + if (atomic_long_read(&n->total_objects)) return 1; } return 0; @@ -3739,15 +3775,32 @@ SLAB_ATTR_RO(object_size); static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) { - return sprintf(buf, "%d\n", s->objects); + return sprintf(buf, "%d\n", oo_objects(s->oo)); } SLAB_ATTR_RO(objs_per_slab); +static ssize_t order_store(struct kmem_cache *s, + const char *buf, size_t length) +{ + unsigned long order; + int err; + + err = strict_strtoul(buf, 10, &order); + if (err) + return err; + + if (order > slub_max_order || order < slub_min_order) + return -EINVAL; + + calculate_sizes(s, order); + return length; +} + static ssize_t order_show(struct kmem_cache *s, char *buf) { - return sprintf(buf, "%d\n", s->order); + return sprintf(buf, "%d\n", oo_order(s->oo)); } -SLAB_ATTR_RO(order); +SLAB_ATTR(order); static ssize_t ctor_show(struct kmem_cache *s, char *buf) { @@ -3768,7 +3821,7 @@ SLAB_ATTR_RO(aliases); static ssize_t slabs_show(struct kmem_cache *s, char *buf) { - return show_slab_objects(s, buf, SO_FULL|SO_PARTIAL|SO_CPU); + return show_slab_objects(s, buf, SO_ALL); } SLAB_ATTR_RO(slabs); @@ -3786,10 +3839,22 @@ SLAB_ATTR_RO(cpu_slabs); static ssize_t objects_show(struct kmem_cache *s, char *buf) { - return show_slab_objects(s, buf, SO_FULL|SO_PARTIAL|SO_CPU|SO_OBJECTS); + return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); } SLAB_ATTR_RO(objects); +static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) +{ + return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); +} +SLAB_ATTR_RO(objects_partial); + +static ssize_t total_objects_show(struct kmem_cache *s, char *buf) +{ + return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); +} +SLAB_ATTR_RO(total_objects); + static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE)); @@ -3869,7 +3934,7 @@ static ssize_t red_zone_store(struct kmem_cache *s, s->flags &= ~SLAB_RED_ZONE; if (buf[0] == '1') s->flags |= SLAB_RED_ZONE; - calculate_sizes(s); + calculate_sizes(s, -1); return length; } SLAB_ATTR(red_zone); @@ -3888,7 +3953,7 @@ static ssize_t poison_store(struct kmem_cache *s, s->flags &= ~SLAB_POISON; if (buf[0] == '1') s->flags |= SLAB_POISON; - calculate_sizes(s); + calculate_sizes(s, -1); return length; } SLAB_ATTR(poison); @@ -3907,7 +3972,7 @@ static ssize_t store_user_store(struct kmem_cache *s, s->flags &= ~SLAB_STORE_USER; if (buf[0] == '1') s->flags |= SLAB_STORE_USER; - calculate_sizes(s); + calculate_sizes(s, -1); return length; } SLAB_ATTR(store_user); @@ -3975,10 +4040,16 @@ static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, const char *buf, size_t length) { - int n = simple_strtoul(buf, NULL, 10); + unsigned long ratio; + int err; + + err = strict_strtoul(buf, 10, &ratio); + if (err) + return err; + + if (ratio < 100) + s->remote_node_defrag_ratio = ratio * 10; - if (n < 100) - s->remote_node_defrag_ratio = n * 10; return length; } SLAB_ATTR(remote_node_defrag_ratio); @@ -4038,7 +4109,7 @@ STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); - +STAT_ATTR(ORDER_FALLBACK, order_fallback); #endif static struct attribute *slab_attrs[] = { @@ -4047,6 +4118,8 @@ static struct attribute *slab_attrs[] = { &objs_per_slab_attr.attr, &order_attr.attr, &objects_attr.attr, + &objects_partial_attr.attr, + &total_objects_attr.attr, &slabs_attr.attr, &partial_attr.attr, &cpu_slabs_attr.attr, @@ -4089,6 +4162,7 @@ static struct attribute *slab_attrs[] = { &deactivate_to_head_attr.attr, &deactivate_to_tail_attr.attr, &deactivate_remote_frees_attr.attr, + &order_fallback_attr.attr, #endif NULL }; @@ -4332,8 +4406,8 @@ __initcall(slab_sysfs_init); */ #ifdef CONFIG_SLABINFO -ssize_t slabinfo_write(struct file *file, const char __user * buffer, - size_t count, loff_t *ppos) +ssize_t slabinfo_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) { return -EINVAL; } @@ -4375,7 +4449,8 @@ static int s_show(struct seq_file *m, void *p) unsigned long nr_partials = 0; unsigned long nr_slabs = 0; unsigned long nr_inuse = 0; - unsigned long nr_objs; + unsigned long nr_objs = 0; + unsigned long nr_free = 0; struct kmem_cache *s; int node; @@ -4389,14 +4464,15 @@ static int s_show(struct seq_file *m, void *p) nr_partials += n->nr_partial; nr_slabs += atomic_long_read(&n->nr_slabs); - nr_inuse += count_partial(n); + nr_objs += atomic_long_read(&n->total_objects); + nr_free += count_partial(n, count_free); } - nr_objs = nr_slabs * s->objects; - nr_inuse += (nr_slabs - nr_partials) * s->objects; + nr_inuse = nr_objs - nr_free; seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse, - nr_objs, s->size, s->objects, (1 << s->order)); + nr_objs, s->size, oo_objects(s->oo), + (1 << oo_order(s->oo))); seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0); seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs, 0UL);