diff --git a/include/linux/slab.h b/include/linux/slab.h index fd2e129fc813..4ee5b2fed164 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -243,27 +243,17 @@ static inline unsigned int arch_slab_minalign(void) #ifdef CONFIG_SLAB /* - * The largest kmalloc size supported by the SLAB allocators is - * 32 megabyte (2^25) or the maximum allocatable page order if that is - * less than 32 MB. - * - * WARNING: Its not easy to increase this value since the allocators have - * to do various tricks to work around compiler limitations in order to - * ensure proper constant folding. + * SLAB and SLUB directly allocates requests fitting in to an order-1 page + * (PAGE_SIZE*2). Larger requests are passed to the page allocator. */ -#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ - (MAX_ORDER + PAGE_SHIFT - 1) : 25) -#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH +#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif #endif #ifdef CONFIG_SLUB -/* - * SLUB directly allocates requests fitting in to an order-1 page - * (PAGE_SIZE*2). Larger requests are passed to the page allocator. - */ #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) #define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) #ifndef KMALLOC_SHIFT_LOW @@ -415,10 +405,6 @@ static __always_inline unsigned int __kmalloc_index(size_t size, if (size <= 512 * 1024) return 19; if (size <= 1024 * 1024) return 20; if (size <= 2 * 1024 * 1024) return 21; - if (size <= 4 * 1024 * 1024) return 22; - if (size <= 8 * 1024 * 1024) return 23; - if (size <= 16 * 1024 * 1024) return 24; - if (size <= 32 * 1024 * 1024) return 25; if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); @@ -428,6 +414,7 @@ static __always_inline unsigned int __kmalloc_index(size_t size, /* Will never be reached. Needed because the compiler may complain */ return -1; } +static_assert(PAGE_SHIFT <= 20); #define kmalloc_index(s) __kmalloc_index(s, true) #endif /* !CONFIG_SLOB */ diff --git a/mm/slab.c b/mm/slab.c index 8c08d7f3dead..10c9af904410 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3585,11 +3585,19 @@ __do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) struct kmem_cache *cachep; void *ret; - if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) - return NULL; + if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { + ret = kmalloc_large_node_notrace(size, flags, node); + + trace_kmalloc_node(caller, ret, NULL, size, + PAGE_SIZE << get_order(size), + flags, node); + return ret; + } + cachep = kmalloc_slab(size, flags); if (unlikely(ZERO_OR_NULL_PTR(cachep))) return cachep; + ret = kmem_cache_alloc_node_trace(cachep, flags, node, size); ret = kasan_kmalloc(cachep, ret, size, flags); @@ -3664,17 +3672,27 @@ EXPORT_SYMBOL(kmem_cache_free); void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p) { - struct kmem_cache *s; - size_t i; local_irq_disable(); - for (i = 0; i < size; i++) { + for (int i = 0; i < size; i++) { void *objp = p[i]; + struct kmem_cache *s; - if (!orig_s) /* called via kfree_bulk */ - s = virt_to_cache(objp); - else + if (!orig_s) { + struct folio *folio = virt_to_folio(objp); + + /* called via kfree_bulk */ + if (!folio_test_slab(folio)) { + local_irq_enable(); + free_large_kmalloc(folio, objp); + local_irq_disable(); + continue; + } + s = folio_slab(folio)->slab_cache; + } else { s = cache_from_obj(orig_s, objp); + } + if (!s) continue; @@ -3703,20 +3721,24 @@ void kfree(const void *objp) { struct kmem_cache *c; unsigned long flags; + struct folio *folio; trace_kfree(_RET_IP_, objp); if (unlikely(ZERO_OR_NULL_PTR(objp))) return; - local_irq_save(flags); - kfree_debugcheck(objp); - c = virt_to_cache(objp); - if (!c) { - local_irq_restore(flags); + + folio = virt_to_folio(objp); + if (!folio_test_slab(folio)) { + free_large_kmalloc(folio, (void *)objp); return; } - debug_check_no_locks_freed(objp, c->object_size); + c = folio_slab(folio)->slab_cache; + + local_irq_save(flags); + kfree_debugcheck(objp); + debug_check_no_locks_freed(objp, c->object_size); debug_check_no_obj_freed(objp, c->object_size); __cache_free(c, (void *)objp, _RET_IP_); local_irq_restore(flags); @@ -4138,15 +4160,17 @@ void __check_heap_object(const void *ptr, unsigned long n, size_t __ksize(const void *objp) { struct kmem_cache *c; - size_t size; + struct folio *folio; BUG_ON(!objp); if (unlikely(objp == ZERO_SIZE_PTR)) return 0; - c = virt_to_cache(objp); - size = c ? c->object_size : 0; + folio = virt_to_folio(objp); + if (!folio_test_slab(folio)) + return folio_size(folio); - return size; + c = folio_slab(folio)->slab_cache; + return c->object_size; } EXPORT_SYMBOL(__ksize); diff --git a/mm/slab.h b/mm/slab.h index 801a207a5cd7..9808d537f6ba 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -660,6 +660,9 @@ static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) print_tracking(cachep, x); return cachep; } + +void free_large_kmalloc(struct folio *folio, void *object); + #endif /* CONFIG_SLOB */ static inline size_t slab_ksize(const struct kmem_cache *s) diff --git a/mm/slab_common.c b/mm/slab_common.c index 51ccd0545816..5a2e81f42ee9 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -744,8 +744,8 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags) /* * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time. - * kmalloc_index() supports up to 2^25=32MB, so the final entry of the table is - * kmalloc-32M. + * kmalloc_index() supports up to 2^21=2MB, so the final entry of the table is + * kmalloc-2M. */ const struct kmalloc_info_struct kmalloc_info[] __initconst = { INIT_KMALLOC_INFO(0, 0), @@ -769,11 +769,7 @@ const struct kmalloc_info_struct kmalloc_info[] __initconst = { INIT_KMALLOC_INFO(262144, 256k), INIT_KMALLOC_INFO(524288, 512k), INIT_KMALLOC_INFO(1048576, 1M), - INIT_KMALLOC_INFO(2097152, 2M), - INIT_KMALLOC_INFO(4194304, 4M), - INIT_KMALLOC_INFO(8388608, 8M), - INIT_KMALLOC_INFO(16777216, 16M), - INIT_KMALLOC_INFO(33554432, 32M) + INIT_KMALLOC_INFO(2097152, 2M) }; /* @@ -886,6 +882,21 @@ void __init create_kmalloc_caches(slab_flags_t flags) /* Kmalloc array is now usable */ slab_state = UP; } + +void free_large_kmalloc(struct folio *folio, void *object) +{ + unsigned int order = folio_order(folio); + + if (WARN_ON_ONCE(order == 0)) + pr_warn_once("object pointer: 0x%p\n", object); + + kmemleak_free(object); + kasan_kfree_large(object); + + mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, + -(PAGE_SIZE << order)); + __free_pages(folio_page(folio, 0), order); +} #endif /* !CONFIG_SLOB */ gfp_t kmalloc_fix_flags(gfp_t flags) diff --git a/mm/slub.c b/mm/slub.c index 165fe87af204..a659874c5d44 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1704,12 +1704,6 @@ static bool freelist_corrupted(struct kmem_cache *s, struct slab *slab, * Hooks for other subsystems that check memory allocations. In a typical * production configuration these hooks all should produce no code at all. */ -static __always_inline void kfree_hook(void *x) -{ - kmemleak_free(x); - kasan_kfree_large(x); -} - static __always_inline bool slab_free_hook(struct kmem_cache *s, void *x, bool init) { @@ -3550,19 +3544,6 @@ struct detached_freelist { struct kmem_cache *s; }; -static inline void free_large_kmalloc(struct folio *folio, void *object) -{ - unsigned int order = folio_order(folio); - - if (WARN_ON_ONCE(order == 0)) - pr_warn_once("object pointer: 0x%p\n", object); - - kfree_hook(object); - mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, - -(PAGE_SIZE << order)); - __free_pages(folio_page(folio, 0), order); -} - /* * This function progressively scans the array with free objects (with * a limited look ahead) and extract objects belonging to the same