int size; /* The size of an object including meta data */
int objsize; /* The size of an object without meta data */
int offset; /* Free pointer offset. */
- unsigned int order;
+ int order;
/*
* Avoid an extra cache line for UP, SMP and for the node local to
/*
* Kmalloc subsystem.
*/
-#define KMALLOC_SHIFT_LOW 3
-
-#ifdef CONFIG_LARGE_ALLOCS
-#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT) =< 25 ? \
- (MAX_ORDER + PAGE_SHIFT - 1) : 25)
-#else
-#if !defined(CONFIG_MMU) || NR_CPUS > 512 || MAX_NUMNODES > 256
-#define KMALLOC_SHIFT_HIGH 20
+#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
+#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
#else
-#define KMALLOC_SHIFT_HIGH 18
-#endif
+#define KMALLOC_MIN_SIZE 8
#endif
+#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
+
/*
* We keep the general caches in an array of slab caches that are used for
* 2^x bytes of allocations.
* Sorry that the following has to be that ugly but some versions of GCC
* have trouble with constant propagation and loops.
*/
-static inline int kmalloc_index(int size)
+static inline int kmalloc_index(size_t size)
{
- /*
- * We should return 0 if size == 0 but we use the smallest object
- * here for SLAB legacy reasons.
- */
- WARN_ON_ONCE(size == 0);
+ if (!size)
+ return 0;
- if (size > (1 << KMALLOC_SHIFT_HIGH))
+ if (size > KMALLOC_MAX_SIZE)
return -1;
+ if (size <= KMALLOC_MIN_SIZE)
+ return KMALLOC_SHIFT_LOW;
+
if (size > 64 && size <= 96)
return 1;
if (size > 128 && size <= 192)
if (size <= 64 * 1024) return 16;
if (size <= 128 * 1024) return 17;
if (size <= 256 * 1024) return 18;
-#if KMALLOC_SHIFT_HIGH > 18
if (size <= 512 * 1024) return 19;
if (size <= 1024 * 1024) return 20;
-#endif
-#if KMALLOC_SHIFT_HIGH > 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;
-#endif
return -1;
/*
if (index == 0)
return NULL;
- if (index < 0) {
+ /*
+ * This function only gets expanded if __builtin_constant_p(size), so
+ * testing it here shouldn't be needed. But some versions of gcc need
+ * help.
+ */
+ if (__builtin_constant_p(size) && index < 0) {
/*
* Generate a link failure. Would be great if we could
* do something to stop the compile here.
#define SLUB_DMA 0
#endif
+
+/*
+ * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
+ *
+ * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
+ *
+ * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
+ * Both make kfree a no-op.
+ */
+#define ZERO_SIZE_PTR ((void *)16)
+
+
+void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
+void *__kmalloc(size_t size, gfp_t flags);
+
static inline void *kmalloc(size_t size, gfp_t flags)
{
if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
struct kmem_cache *s = kmalloc_slab(size);
if (!s)
- return NULL;
+ return ZERO_SIZE_PTR;
return kmem_cache_alloc(s, flags);
} else
struct kmem_cache *s = kmalloc_slab(size);
if (!s)
- return NULL;
+ return ZERO_SIZE_PTR;
return kmem_cache_zalloc(s, flags);
} else
}
#ifdef CONFIG_NUMA
-extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
+void *__kmalloc_node(size_t size, gfp_t flags, int node);
+void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
struct kmem_cache *s = kmalloc_slab(size);
if (!s)
- return NULL;
+ return ZERO_SIZE_PTR;
return kmem_cache_alloc_node(s, flags, node);
} else