diff options
Diffstat (limited to 'include/linux/slab.h')
| -rw-r--r-- | include/linux/slab.h | 59 |
1 files changed, 47 insertions, 12 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index 0c97d788762c..083f3ce550bc 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -305,9 +305,21 @@ static inline void __check_heap_object(const void *ptr, unsigned long n, /* * Whenever changing this, take care of that kmalloc_type() and * create_kmalloc_caches() still work as intended. + * + * KMALLOC_NORMAL can contain only unaccounted objects whereas KMALLOC_CGROUP + * is for accounted but unreclaimable and non-dma objects. All the other + * kmem caches can have both accounted and unaccounted objects. */ enum kmalloc_cache_type { KMALLOC_NORMAL = 0, +#ifndef CONFIG_ZONE_DMA + KMALLOC_DMA = KMALLOC_NORMAL, +#endif +#ifndef CONFIG_MEMCG_KMEM + KMALLOC_CGROUP = KMALLOC_NORMAL, +#else + KMALLOC_CGROUP, +#endif KMALLOC_RECLAIM, #ifdef CONFIG_ZONE_DMA KMALLOC_DMA, @@ -319,24 +331,36 @@ enum kmalloc_cache_type { extern struct kmem_cache * kmalloc_caches[NR_KMALLOC_TYPES][KMALLOC_SHIFT_HIGH + 1]; +/* + * Define gfp bits that should not be set for KMALLOC_NORMAL. + */ +#define KMALLOC_NOT_NORMAL_BITS \ + (__GFP_RECLAIMABLE | \ + (IS_ENABLED(CONFIG_ZONE_DMA) ? __GFP_DMA : 0) | \ + (IS_ENABLED(CONFIG_MEMCG_KMEM) ? __GFP_ACCOUNT : 0)) + static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) { -#ifdef CONFIG_ZONE_DMA /* * The most common case is KMALLOC_NORMAL, so test for it - * with a single branch for both flags. + * with a single branch for all the relevant flags. */ - if (likely((flags & (__GFP_DMA | __GFP_RECLAIMABLE)) == 0)) + if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0)) return KMALLOC_NORMAL; /* - * At least one of the flags has to be set. If both are, __GFP_DMA - * is more important. + * At least one of the flags has to be set. Their priorities in + * decreasing order are: + * 1) __GFP_DMA + * 2) __GFP_RECLAIMABLE + * 3) __GFP_ACCOUNT */ - return flags & __GFP_DMA ? KMALLOC_DMA : KMALLOC_RECLAIM; -#else - return flags & __GFP_RECLAIMABLE ? KMALLOC_RECLAIM : KMALLOC_NORMAL; -#endif + if (IS_ENABLED(CONFIG_ZONE_DMA) && (flags & __GFP_DMA)) + return KMALLOC_DMA; + if (!IS_ENABLED(CONFIG_MEMCG_KMEM) || (flags & __GFP_RECLAIMABLE)) + return KMALLOC_RECLAIM; + else + return KMALLOC_CGROUP; } /* @@ -346,8 +370,14 @@ static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) * 1 = 65 .. 96 bytes * 2 = 129 .. 192 bytes * n = 2^(n-1)+1 .. 2^n + * + * Note: __kmalloc_index() is compile-time optimized, and not runtime optimized; + * typical usage is via kmalloc_index() and therefore evaluated at compile-time. + * Callers where !size_is_constant should only be test modules, where runtime + * overheads of __kmalloc_index() can be tolerated. Also see kmalloc_slab(). */ -static __always_inline unsigned int kmalloc_index(size_t size) +static __always_inline unsigned int __kmalloc_index(size_t size, + bool size_is_constant) { if (!size) return 0; @@ -382,12 +412,17 @@ static __always_inline unsigned int kmalloc_index(size_t size) if (size <= 8 * 1024 * 1024) return 23; if (size <= 16 * 1024 * 1024) return 24; if (size <= 32 * 1024 * 1024) return 25; - if (size <= 64 * 1024 * 1024) return 26; - BUG(); + + if ((IS_ENABLED(CONFIG_CC_IS_GCC) || CONFIG_CLANG_VERSION >= 110000) + && !IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && size_is_constant) + BUILD_BUG_ON_MSG(1, "unexpected size in kmalloc_index()"); + else + BUG(); /* Will never be reached. Needed because the compiler may complain */ return -1; } +#define kmalloc_index(s) __kmalloc_index(s, true) #endif /* !CONFIG_SLOB */ void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc; |