diff options
-rw-r--r-- | include/linux/mm_types.h | 5 | ||||
-rw-r--r-- | mm/slub.c | 70 |
2 files changed, 24 insertions, 51 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index bfee0bd..34023c6 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -64,10 +64,7 @@ struct page { #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS spinlock_t ptl; #endif - struct { - struct kmem_cache *slab; /* SLUB: Pointer to slab */ - void *end; /* SLUB: end marker */ - }; + struct kmem_cache *slab; /* SLUB: Pointer to slab */ struct page *first_page; /* Compound tail pages */ }; union { @@ -291,32 +291,15 @@ static inline struct kmem_cache_cpu *get_cpu_slab(struct kmem_cache *s, int cpu) #endif } -/* - * The end pointer in a slab is special. It points to the first object in the - * slab but has bit 0 set to mark it. - * - * Note that SLUB relies on page_mapping returning NULL for pages with bit 0 - * in the mapping set. - */ -static inline int is_end(void *addr) -{ - return (unsigned long)addr & PAGE_MAPPING_ANON; -} - -static void *slab_address(struct page *page) -{ - return page->end - PAGE_MAPPING_ANON; -} - static inline int check_valid_pointer(struct kmem_cache *s, struct page *page, const void *object) { void *base; - if (object == page->end) + if (!object) return 1; - base = slab_address(page); + base = page_address(page); if (object < base || object >= base + s->objects * s->size || (object - base) % s->size) { return 0; @@ -349,8 +332,7 @@ static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) /* Scan freelist */ #define for_each_free_object(__p, __s, __free) \ - for (__p = (__free); (__p) != page->end; __p = get_freepointer((__s),\ - __p)) + for (__p = (__free); __p; __p = get_freepointer((__s), __p)) /* Determine object index from a given position */ static inline int slab_index(void *p, struct kmem_cache *s, void *addr) @@ -502,7 +484,7 @@ static void slab_fix(struct kmem_cache *s, char *fmt, ...) static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) { unsigned int off; /* Offset of last byte */ - u8 *addr = slab_address(page); + u8 *addr = page_address(page); print_tracking(s, p); @@ -680,7 +662,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page) if (!(s->flags & SLAB_POISON)) return 1; - start = slab_address(page); + start = page_address(page); end = start + (PAGE_SIZE << s->order); length = s->objects * s->size; remainder = end - (start + length); @@ -748,7 +730,7 @@ static int check_object(struct kmem_cache *s, struct page *page, * of the free objects in this slab. May cause * another error because the object count is now wrong. */ - set_freepointer(s, p, page->end); + set_freepointer(s, p, NULL); return 0; } return 1; @@ -782,18 +764,18 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search) void *fp = page->freelist; void *object = NULL; - while (fp != page->end && nr <= s->objects) { + while (fp && nr <= s->objects) { if (fp == search) return 1; if (!check_valid_pointer(s, page, fp)) { if (object) { object_err(s, page, object, "Freechain corrupt"); - set_freepointer(s, object, page->end); + set_freepointer(s, object, NULL); break; } else { slab_err(s, page, "Freepointer corrupt"); - page->freelist = page->end; + page->freelist = NULL; page->inuse = s->objects; slab_fix(s, "Freelist cleared"); return 0; @@ -899,7 +881,7 @@ bad: */ slab_fix(s, "Marking all objects used"); page->inuse = s->objects; - page->freelist = page->end; + page->freelist = NULL; } return 0; } @@ -939,7 +921,7 @@ static int free_debug_processing(struct kmem_cache *s, struct page *page, } /* Special debug activities for freeing objects */ - if (!SlabFrozen(page) && page->freelist == page->end) + if (!SlabFrozen(page) && !page->freelist) remove_full(s, page); if (s->flags & SLAB_STORE_USER) set_track(s, object, TRACK_FREE, addr); @@ -1124,7 +1106,6 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) SetSlabDebug(page); start = page_address(page); - page->end = start + 1; if (unlikely(s->flags & SLAB_POISON)) memset(start, POISON_INUSE, PAGE_SIZE << s->order); @@ -1136,7 +1117,7 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) last = p; } setup_object(s, page, last); - set_freepointer(s, last, page->end); + set_freepointer(s, last, NULL); page->freelist = start; page->inuse = 0; @@ -1152,7 +1133,7 @@ static void __free_slab(struct kmem_cache *s, struct page *page) void *p; slab_pad_check(s, page); - for_each_object(p, s, slab_address(page)) + for_each_object(p, s, page_address(page)) check_object(s, page, p, 0); ClearSlabDebug(page); } @@ -1162,7 +1143,6 @@ static void __free_slab(struct kmem_cache *s, struct page *page) NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, -pages); - page->mapping = NULL; __free_pages(page, s->order); } @@ -1366,7 +1346,7 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) ClearSlabFrozen(page); if (page->inuse) { - if (page->freelist != page->end) { + if (page->freelist) { add_partial(n, page, tail); stat(c, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); } else { @@ -1410,12 +1390,8 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) * Merge cpu freelist into freelist. Typically we get here * because both freelists are empty. So this is unlikely * to occur. - * - * We need to use _is_end here because deactivate slab may - * be called for a debug slab. Then c->freelist may contain - * a dummy pointer. */ - while (unlikely(!is_end(c->freelist))) { + while (unlikely(c->freelist)) { void **object; tail = 0; /* Hot objects. Put the slab first */ @@ -1517,7 +1493,7 @@ static void *__slab_alloc(struct kmem_cache *s, stat(c, ALLOC_REFILL); load_freelist: object = c->page->freelist; - if (unlikely(object == c->page->end)) + if (unlikely(!object)) goto another_slab; if (unlikely(SlabDebug(c->page))) goto debug; @@ -1525,7 +1501,7 @@ load_freelist: object = c->page->freelist; c->freelist = object[c->offset]; c->page->inuse = s->objects; - c->page->freelist = c->page->end; + c->page->freelist = NULL; c->node = page_to_nid(c->page); unlock_out: slab_unlock(c->page); @@ -1607,7 +1583,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s, local_irq_save(flags); c = get_cpu_slab(s, smp_processor_id()); - if (unlikely(is_end(c->freelist) || !node_match(c, node))) + if (unlikely(!c->freelist || !node_match(c, node))) object = __slab_alloc(s, gfpflags, node, addr, c); @@ -1677,7 +1653,7 @@ checks_ok: * was not on the partial list before * then add it. */ - if (unlikely(prior == page->end)) { + if (unlikely(!prior)) { add_partial(get_node(s, page_to_nid(page)), page, 1); stat(c, FREE_ADD_PARTIAL); } @@ -1687,7 +1663,7 @@ out_unlock: return; slab_empty: - if (prior != page->end) { + if (prior) { /* * Slab still on the partial list. */ @@ -1910,7 +1886,7 @@ static void init_kmem_cache_cpu(struct kmem_cache *s, struct kmem_cache_cpu *c) { c->page = NULL; - c->freelist = (void *)PAGE_MAPPING_ANON; + c->freelist = NULL; c->node = 0; c->offset = s->offset / sizeof(void *); c->objsize = s->objsize; @@ -3199,7 +3175,7 @@ static int validate_slab(struct kmem_cache *s, struct page *page, unsigned long *map) { void *p; - void *addr = slab_address(page); + void *addr = page_address(page); if (!check_slab(s, page) || !on_freelist(s, page, NULL)) @@ -3482,7 +3458,7 @@ static int add_location(struct loc_track *t, struct kmem_cache *s, static void process_slab(struct loc_track *t, struct kmem_cache *s, struct page *page, enum track_item alloc) { - void *addr = slab_address(page); + void *addr = page_address(page); DECLARE_BITMAP(map, s->objects); void *p; |