Commit 039363f3 authored by Christoph Lameter's avatar Christoph Lameter Committed by Pekka Enberg
Browse files

mm, sl[aou]b: Extract common code for kmem_cache_create() 



Kmem_cache_create() does a variety of sanity checks but those
vary depending on the allocator. Use the strictest tests and put them into
a slab_common file. Make the tests conditional on CONFIG_DEBUG_VM.

This patch has the effect of adding sanity checks for SLUB and SLOB
under CONFIG_DEBUG_VM and removes the checks in SLAB for !CONFIG_DEBUG_VM.

Signed-off-by: default avatarChristoph Lameter <cl@linux.com>
Signed-off-by: default avatarPekka Enberg <penberg@kernel.org>
parent 068ce415

include/linux/slab.h

+4 −0
Original line number Diff line number Diff line
@@ -130,6 +130,10 @@ int kmem_cache_shrink(struct kmem_cache *); 
void kmem_cache_free(struct kmem_cache *, void *);

unsigned int kmem_cache_size(struct kmem_cache *);



/* Slab internal function */

struct kmem_cache *__kmem_cache_create(const char *, size_t, size_t,

			unsigned long,

			void (*)(void *));

/*

 * Please use this macro to create slab caches. Simply specify the

 * name of the structure and maybe some flags that are listed above.

mm/Makefile

+2 −1
Original line number Diff line number Diff line
@@ -16,7 +16,8 @@ obj-y := filemap.o mempool.o oom_kill.o fadvise.o \ 
			   readahead.o swap.o truncate.o vmscan.o shmem.o \

			   prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \

			   page_isolation.o mm_init.o mmu_context.o percpu.o \

			   compaction.o $(mmu-y)

			   compaction.o slab_common.o $(mmu-y)



obj-y += init-mm.o



ifdef CONFIG_NO_BOOTMEM

mm/slab.c

+9 −15
Original line number Diff line number Diff line
@@ -1558,7 +1558,7 @@ void __init kmem_cache_init(void) 
	 * bug.

	 */



	sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name,

	sizes[INDEX_AC].cs_cachep = __kmem_cache_create(names[INDEX_AC].name,

					sizes[INDEX_AC].cs_size,

					ARCH_KMALLOC_MINALIGN,

					ARCH_KMALLOC_FLAGS|SLAB_PANIC,
@@ -1566,7 +1566,7 @@ void __init kmem_cache_init(void) 


	if (INDEX_AC != INDEX_L3) {

		sizes[INDEX_L3].cs_cachep =

			kmem_cache_create(names[INDEX_L3].name,

			__kmem_cache_create(names[INDEX_L3].name,

				sizes[INDEX_L3].cs_size,

				ARCH_KMALLOC_MINALIGN,

				ARCH_KMALLOC_FLAGS|SLAB_PANIC,
@@ -1584,14 +1584,14 @@ void __init kmem_cache_init(void) 
		 * allow tighter packing of the smaller caches.

		 */

		if (!sizes->cs_cachep) {

			sizes->cs_cachep = kmem_cache_create(names->name,

			sizes->cs_cachep = __kmem_cache_create(names->name,

					sizes->cs_size,

					ARCH_KMALLOC_MINALIGN,

					ARCH_KMALLOC_FLAGS|SLAB_PANIC,

					NULL);

		}

#ifdef CONFIG_ZONE_DMA

		sizes->cs_dmacachep = kmem_cache_create(

		sizes->cs_dmacachep = __kmem_cache_create(

					names->name_dma,

					sizes->cs_size,

					ARCH_KMALLOC_MINALIGN,
@@ -2220,7 +2220,7 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) 
}



/**

 * kmem_cache_create - Create a cache.

 * __kmem_cache_create - Create a cache.

 * @name: A string which is used in /proc/slabinfo to identify this cache.

 * @size: The size of objects to be created in this cache.

 * @align: The required alignment for the objects.
@@ -2247,7 +2247,7 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) 
 * as davem.

 */

struct kmem_cache *

kmem_cache_create (const char *name, size_t size, size_t align,

__kmem_cache_create (const char *name, size_t size, size_t align,

	unsigned long flags, void (*ctor)(void *))

{

	size_t left_over, slab_size, ralign;
@@ -2388,7 +2388,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, 
	/* Get cache's description obj. */

	cachep = kmem_cache_zalloc(&cache_cache, gfp);

	if (!cachep)

		goto oops;

		return NULL;



	cachep->nodelists = (struct kmem_list3 **)&cachep->array[nr_cpu_ids];

	cachep->object_size = size;
@@ -2445,8 +2445,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, 
		printk(KERN_ERR

		       "kmem_cache_create: couldn't create cache %s.\n", name);

		kmem_cache_free(&cache_cache, cachep);

		cachep = NULL;

		goto oops;

		return NULL;

	}

	slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t)

			  + sizeof(struct slab), align);
@@ -2504,8 +2503,7 @@ kmem_cache_create (const char *name, size_t size, size_t align, 


	if (setup_cpu_cache(cachep, gfp)) {

		__kmem_cache_destroy(cachep);

		cachep = NULL;

		goto oops;

		return NULL;

	}



	if (flags & SLAB_DEBUG_OBJECTS) {
@@ -2521,16 +2519,12 @@ kmem_cache_create (const char *name, size_t size, size_t align, 
	/* cache setup completed, link it into the list */

	list_add(&cachep->list, &cache_chain);

oops:

	if (!cachep && (flags & SLAB_PANIC))

		panic("kmem_cache_create(): failed to create slab `%s'\n",

		      name);

	if (slab_is_available()) {

		mutex_unlock(&cache_chain_mutex);

		put_online_cpus();

	}

	return cachep;

}

EXPORT_SYMBOL(kmem_cache_create);



#if DEBUG

static void check_irq_off(void)

mm/slab_common.c

0 → 100644
+68 −0
Original line number Diff line number Diff line 
/*

 * Slab allocator functions that are independent of the allocator strategy

 *

 * (C) 2012 Christoph Lameter <cl@linux.com>

 */

#include <linux/slab.h>



#include <linux/mm.h>

#include <linux/poison.h>

#include <linux/interrupt.h>

#include <linux/memory.h>

#include <linux/compiler.h>

#include <linux/module.h>



#include <asm/cacheflush.h>

#include <asm/tlbflush.h>

#include <asm/page.h>



/*

 * kmem_cache_create - Create a cache.

 * @name: A string which is used in /proc/slabinfo to identify this cache.

 * @size: The size of objects to be created in this cache.

 * @align: The required alignment for the objects.

 * @flags: SLAB flags

 * @ctor: A constructor for the objects.

 *

 * Returns a ptr to the cache on success, NULL on failure.

 * Cannot be called within a interrupt, but can be interrupted.

 * The @ctor is run when new pages are allocated by the cache.

 *

 * The flags are

 *

 * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)

 * to catch references to uninitialised memory.

 *

 * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check

 * for buffer overruns.

 *

 * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware

 * cacheline.  This can be beneficial if you're counting cycles as closely

 * as davem.

 */



struct kmem_cache *kmem_cache_create(const char *name, size_t size, size_t align,

		unsigned long flags, void (*ctor)(void *))

{

	struct kmem_cache *s = NULL;



#ifdef CONFIG_DEBUG_VM

	if (!name || in_interrupt() || size < sizeof(void *) ||

		size > KMALLOC_MAX_SIZE) {

		printk(KERN_ERR "kmem_cache_create(%s) integrity check"

			" failed\n", name);

		goto out;

	}

#endif



	s = __kmem_cache_create(name, size, align, flags, ctor);



#ifdef CONFIG_DEBUG_VM

out:

#endif

	if (!s && (flags & SLAB_PANIC))

		panic("kmem_cache_create: Failed to create slab '%s'\n", name);



	return s;

}

EXPORT_SYMBOL(kmem_cache_create);

mm/slob.c

+3 −5
Original line number Diff line number Diff line
@@ -506,7 +506,7 @@ size_t ksize(const void *block) 
}

EXPORT_SYMBOL(ksize);



struct kmem_cache *kmem_cache_create(const char *name, size_t size,

struct kmem_cache *__kmem_cache_create(const char *name, size_t size,

	size_t align, unsigned long flags, void (*ctor)(void *))

{

	struct kmem_cache *c;
@@ -529,13 +529,11 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size, 
			c->align = ARCH_SLAB_MINALIGN;

		if (c->align < align)

			c->align = align;

	} else if (flags & SLAB_PANIC)

		panic("Cannot create slab cache %s\n", name);



		kmemleak_alloc(c, sizeof(struct kmem_cache), 1, GFP_KERNEL);

	}

	return c;

}

EXPORT_SYMBOL(kmem_cache_create);



void kmem_cache_destroy(struct kmem_cache *c)

{

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