[glommer-memcg:slab-common/kmalloc 29/30] mm/slab_common.c:274:68: sparse: incorrect type in argumen

Fengguang Wu
2012-09-28T11:16:24Z

[-- Attachment #1: Type: text/plain, Size: 3361 bytes --]

Hi Christoph,

FYI, there are new sparse warnings show up in

tree: git://git.kernel.org/pub/scm/linux/kernel/git/glommer/memcg.git slab-common/kmalloc
head: f957c1ead131972db578b945e25982f4607da6ba
commit: f957c1ead131972db578b945e25982f4607da6ba [29/30] CK1 [13/13] Common function to create the kmalloc array

+ mm/slab_common.c:274:68: sparse: incorrect type in argument 3 (different base types)
mm/slab_common.c:274:68: expected unsigned long [unsigned] flags
mm/slab_common.c:274:68: got restricted gfp_t [usertype] flags
mm/slab_common.c:277:69: sparse: incorrect type in argument 3 (different base types)
mm/slab_common.c:277:69: expected unsigned long [unsigned] flags
mm/slab_common.c:277:69: got restricted gfp_t [usertype] flags
mm/slab_common.c:282:65: sparse: incorrect type in argument 3 (different base types)
mm/slab_common.c:282:65: expected unsigned long [unsigned] flags
mm/slab_common.c:282:65: got restricted gfp_t [usertype] flags
+ mm/slab_common.c:310:56: sparse: restricted gfp_t degrades to integer
mm/slab_common.c: In function 'create_boot_cache':
mm/slab_common.c:236:6: warning: format '%ld' expects argument of type 'long int', but argument 3 has type 'size_t' [-Wformat]

vim +274 mm/slab_common.c

55a6b9f9 (Christoph Lameter 2012-09-26 258) #ifdef CONFIG_ZONE_DMA
55a6b9f9 (Christoph Lameter 2012-09-26 259) struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
55a6b9f9 (Christoph Lameter 2012-09-26 260) EXPORT_SYMBOL(kmalloc_dma_caches);
55a6b9f9 (Christoph Lameter 2012-09-26 261) #endif
55a6b9f9 (Christoph Lameter 2012-09-26 262)
f957c1ea (Christoph Lameter 2012-09-26 263) /*
f957c1ea (Christoph Lameter 2012-09-26 264) * Create the kmalloc array. Some of the regular kmalloc arrays
f957c1ea (Christoph Lameter 2012-09-26 265) * may already have been created because they were needed to
f957c1ea (Christoph Lameter 2012-09-26 266) * enable allocations for slab creation.
f957c1ea (Christoph Lameter 2012-09-26 267) */
f957c1ea (Christoph Lameter 2012-09-26 268) void __init create_kmalloc_caches(gfp_t flags)
f957c1ea (Christoph Lameter 2012-09-26 269) {
f957c1ea (Christoph Lameter 2012-09-26 270) int i;
f957c1ea (Christoph Lameter 2012-09-26 271)
f957c1ea (Christoph Lameter 2012-09-26 272) /* Caches that are not of the two-to-the-power-of size */
f957c1ea (Christoph Lameter 2012-09-26 273) if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1])
f957c1ea (Christoph Lameter 2012-09-26 @274) kmalloc_caches[1] = create_kmalloc_cache(NULL, 96, flags);
f957c1ea (Christoph Lameter 2012-09-26 275)
f957c1ea (Christoph Lameter 2012-09-26 276) if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2])
f957c1ea (Christoph Lameter 2012-09-26 277) kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags);
f957c1ea (Christoph Lameter 2012-09-26 278)
f957c1ea (Christoph Lameter 2012-09-26 279) for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
f957c1ea (Christoph Lameter 2012-09-26 280) if (!kmalloc_caches[i])
f957c1ea (Christoph Lameter 2012-09-26 281) kmalloc_caches[i] = create_kmalloc_cache(NULL,
f957c1ea (Christoph Lameter 2012-09-26 282) 1 << i, flags);

---
0-DAY kernel build testing backend Open Source Technology Centre
Fengguang Wu, Yuanhan Liu Intel Corporation

[-- Attachment #2: slab_common.c --]
[-- Type: text/x-csrc, Size: 7532 bytes --]

/*
* 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 <linux/cpu.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/page.h>

#include "slab.h"

enum slab_state slab_state;
LIST_HEAD(slab_caches);
DEFINE_MUTEX(slab_mutex);
struct kmem_cache *kmem_cache;

#ifdef CONFIG_DEBUG_VM
static int kmem_cache_sanity_check(const char *name, size_t size)
{
struct kmem_cache *s = NULL;

if (!name || in_interrupt() || size < sizeof(void *) ||
size > KMALLOC_MAX_SIZE) {
pr_err("kmem_cache_create(%s) integrity check failed\n", name);
return -EINVAL;
}

list_for_each_entry(s, &slab_caches, list) {
char tmp;
int res;

/*
* This happens when the module gets unloaded and doesn't
* destroy its slab cache and no-one else reuses the vmalloc
* area of the module. Print a warning.
*/
res = probe_kernel_address(s->name, tmp);
if (res) {
pr_err("Slab cache with size %d has lost its name\n",
s->object_size);
continue;
}

if (!strcmp(s->name, name)) {
pr_err("%s (%s): Cache name already exists.\n",
__func__, name);
dump_stack();
s = NULL;
return -EINVAL;
}
}

WARN_ON(strchr(name, ' ')); /* It confuses parsers */
return 0;
}
#else
static inline int kmem_cache_sanity_check(const char *name, size_t size)
{
return 0;
}
#endif

/*
* Figure out what the alignment of the objects will be given a set of
* flags, a user specified alignment and the size of the objects.
*/
unsigned long calculate_alignment(unsigned long flags,
unsigned long align, unsigned long size)
{
/*
* If the user wants hardware cache aligned objects then follow that
* suggestion if the object is sufficiently large.
*
* The hardware cache alignment cannot override the specified
* alignment though. If that is greater then use it.
*/
if (flags & SLAB_HWCACHE_ALIGN) {
unsigned long ralign = cache_line_size();
while (size <= ralign / 2)
ralign /= 2;
align = max(align, ralign);
}

if (align < ARCH_SLAB_MINALIGN)
align = ARCH_SLAB_MINALIGN;

return ALIGN(align, sizeof(void *));
}

/*
* 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;
int err = 0;

get_online_cpus();
mutex_lock(&slab_mutex);

if (!kmem_cache_sanity_check(name, size) == 0)
goto out_locked;

s = __kmem_cache_alias(name, size, align, flags, ctor);
if (s)
goto out_locked;

s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL);
if (s) {
s->object_size = s->size = size;
s->align = calculate_alignment(flags, align, size);
s->ctor = ctor;
s->name = kstrdup(name, GFP_KERNEL);
if (!s->name) {
kmem_cache_free(kmem_cache, s);
err = -ENOMEM;
goto out_locked;
}

err = __kmem_cache_create(s, flags);
if (!err) {

s->refcount = 1;
list_add(&s->list, &slab_caches);

} else {
kfree(s->name);
kmem_cache_free(kmem_cache, s);
}
} else
err = -ENOMEM;

out_locked:
mutex_unlock(&slab_mutex);
put_online_cpus();

if (err) {

if (flags & SLAB_PANIC)
panic("kmem_cache_create: Failed to create slab '%s'. Error %d\n",
name, err);
else {
printk(KERN_WARNING "kmem_cache_create(%s) failed with error %d",
name, err);
dump_stack();
}

return NULL;
}

return s;
}
EXPORT_SYMBOL(kmem_cache_create);

void kmem_cache_destroy(struct kmem_cache *s)
{
get_online_cpus();
mutex_lock(&slab_mutex);
s->refcount--;
if (!s->refcount) {
list_del(&s->list);

if (!__kmem_cache_shutdown(s)) {
if (s->flags & SLAB_DESTROY_BY_RCU)
rcu_barrier();

kfree(s->name);
kmem_cache_free(kmem_cache, s);
} else {
list_add(&s->list, &slab_caches);
printk(KERN_ERR "kmem_cache_destroy %s: Slab cache still has objects\n",
s->name);
dump_stack();
}
}
mutex_unlock(&slab_mutex);
put_online_cpus();
}
EXPORT_SYMBOL(kmem_cache_destroy);

int slab_is_available(void)
{
return slab_state >= UP;
}

#ifndef CONFIG_SLOB

/* Create a cache during boot when no slab services are available yet */
void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t size,
unsigned long flags)
{
int err;

s->name = name;
s->size = s->object_size = size;
s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size);
err = __kmem_cache_create(s, flags);

if (err)
panic("Creation of kmalloc slab %s size=%ld failed. Reason %d\n",
name, size, err);

list_add(&s->list, &slab_caches);
s->refcount = -1; /* Exempt from merging for now */
}

struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size,
unsigned long flags)
{
struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT);

if (!s)
panic("Out of memory when creating slab %s\n", name);

create_boot_cache(s, name, size, flags);
s->refcount = 1;
return s;
}

struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
EXPORT_SYMBOL(kmalloc_caches);

#ifdef CONFIG_ZONE_DMA
struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
EXPORT_SYMBOL(kmalloc_dma_caches);
#endif

/*
* Create the kmalloc array. Some of the regular kmalloc arrays
* may already have been created because they were needed to
* enable allocations for slab creation.
*/
void __init create_kmalloc_caches(gfp_t flags)
{
int i;

/* Caches that are not of the two-to-the-power-of size */
if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1])
kmalloc_caches[1] = create_kmalloc_cache(NULL, 96, flags);

if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2])
kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags);

for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
if (!kmalloc_caches[i])
kmalloc_caches[i] = create_kmalloc_cache(NULL,
1 << i, flags);

/* Kmalloc array is now usable */
slab_state = UP;

for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
struct kmem_cache *s = kmalloc_caches[i];
char *n;

if (s) {
n = kasprintf(GFP_NOWAIT, "kmalloc-%d", kmalloc_size(i));

BUG_ON(!n);
s->name = n;
}
}

#ifdef CONFIG_ZONE_DMA
for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
struct kmem_cache *s = kmalloc_caches[i];

if (s) {
int size = kmalloc_size(i);
char *n = kasprintf(GFP_NOWAIT,
"dma-kmalloc-%d", size);

BUG_ON(!n);
kmalloc_dma_caches[i] = create_kmalloc_cache(n,
size, SLAB_CACHE_DMA | flags);
}
}
#endif
}

#endif /* !CONFIG_SLOB */