Group short-lived and reclaimable kernel allocations

[sfrench/cifs-2.6.git] / include / linux / slab.h

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 27402fea9b794d5e0f0960dd41bc67069ba4af49..3a5bad3ad126c2a901cac50e7a69579c3f4e40a5 100644 (file)
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -24,12 +24,27 @@
 #define SLAB_HWCACHE_ALIGN     0x00002000UL    /* Align objs on cache lines */
 #define SLAB_CACHE_DMA         0x00004000UL    /* Use GFP_DMA memory */
 #define SLAB_STORE_USER                0x00010000UL    /* DEBUG: Store the last owner for bug hunting */
-#define SLAB_RECLAIM_ACCOUNT   0x00020000UL    /* Objects are reclaimable */
 #define SLAB_PANIC             0x00040000UL    /* Panic if kmem_cache_create() fails */
 #define SLAB_DESTROY_BY_RCU    0x00080000UL    /* Defer freeing slabs to RCU */
 #define SLAB_MEM_SPREAD                0x00100000UL    /* Spread some memory over cpuset */
 #define SLAB_TRACE             0x00200000UL    /* Trace allocations and frees */
 
+/* The following flags affect the page allocator grouping pages by mobility */
+#define SLAB_RECLAIM_ACCOUNT   0x00020000UL            /* Objects are reclaimable */
+#define SLAB_TEMPORARY         SLAB_RECLAIM_ACCOUNT    /* Objects are short-lived */
+/*
+ * 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)
+
+#define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
+                               (unsigned long)ZERO_SIZE_PTR)
+
 /*
  * struct kmem_cache related prototypes
  */
@@ -38,11 +53,9 @@ int slab_is_available(void);
 
 struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
                        unsigned long,
-                       void (*)(void *, struct kmem_cache *, unsigned long),
                        void (*)(void *, struct kmem_cache *, unsigned long));
 void kmem_cache_destroy(struct kmem_cache *);
 int kmem_cache_shrink(struct kmem_cache *);
-void *kmem_cache_zalloc(struct kmem_cache *, gfp_t);
 void kmem_cache_free(struct kmem_cache *, void *);
 unsigned int kmem_cache_size(struct kmem_cache *);
 const char *kmem_cache_name(struct kmem_cache *);
@@ -58,7 +71,7 @@ int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr);
  */
 #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
                sizeof(struct __struct), __alignof__(struct __struct),\
-               (__flags), NULL, NULL)
+               (__flags), NULL)
 
 /*
  * The largest kmalloc size supported by the slab allocators is
@@ -78,11 +91,37 @@ int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr);
 /*
  * Common kmalloc functions provided by all allocators
  */
-void *__kzalloc(size_t, gfp_t);
 void * __must_check krealloc(const void *, size_t, gfp_t);
 void kfree(const void *);
 size_t ksize(const void *);
 
+/*
+ * Allocator specific definitions. These are mainly used to establish optimized
+ * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by
+ * selecting the appropriate general cache at compile time.
+ *
+ * Allocators must define at least:
+ *
+ *     kmem_cache_alloc()
+ *     __kmalloc()
+ *     kmalloc()
+ *
+ * Those wishing to support NUMA must also define:
+ *
+ *     kmem_cache_alloc_node()
+ *     kmalloc_node()
+ *
+ * See each allocator definition file for additional comments and
+ * implementation notes.
+ */
+#ifdef CONFIG_SLUB
+#include <linux/slub_def.h>
+#elif defined(CONFIG_SLOB)
+#include <linux/slob_def.h>
+#else
+#include <linux/slab_def.h>
+#endif
+
 /**
  * kcalloc - allocate memory for an array. The memory is set to zero.
  * @n: number of elements.
@@ -138,37 +177,9 @@ static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 {
        if (n != 0 && size > ULONG_MAX / n)
                return NULL;
-       return __kzalloc(n * size, flags);
+       return __kmalloc(n * size, flags | __GFP_ZERO);
 }
 
-/*
- * Allocator specific definitions. These are mainly used to establish optimized
- * ways to convert kmalloc() calls to kmem_cache_alloc() invocations by
- * selecting the appropriate general cache at compile time.
- *
- * Allocators must define at least:
- *
- *     kmem_cache_alloc()
- *     __kmalloc()
- *     kmalloc()
- *     kzalloc()
- *
- * Those wishing to support NUMA must also define:
- *
- *     kmem_cache_alloc_node()
- *     kmalloc_node()
- *
- * See each allocator definition file for additional comments and
- * implementation notes.
- */
-#ifdef CONFIG_SLUB
-#include <linux/slub_def.h>
-#elif defined(CONFIG_SLOB)
-#include <linux/slob_def.h>
-#else
-#include <linux/slab_def.h>
-#endif
-
 #if !defined(CONFIG_NUMA) && !defined(CONFIG_SLOB)
 /**
  * kmalloc_node - allocate memory from a specific node
@@ -242,5 +253,23 @@ extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, void *);
 
 #endif /* DEBUG_SLAB */
 
+/*
+ * Shortcuts
+ */
+static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
+{
+       return kmem_cache_alloc(k, flags | __GFP_ZERO);
+}
+
+/**
+ * kzalloc - allocate memory. The memory is set to zero.
+ * @size: how many bytes of memory are required.
+ * @flags: the type of memory to allocate (see kmalloc).
+ */
+static inline void *kzalloc(size_t size, gfp_t flags)
+{
+       return kmalloc(size, flags | __GFP_ZERO);
+}
+
 #endif /* __KERNEL__ */
 #endif /* _LINUX_SLAB_H */