Merge branch 'slab-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6

* 'slab-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slab: fix DEBUG_SLAB warning
  slab: shrink sizeof(struct kmem_cache)
  slab: fix DEBUG_SLAB build
  SLUB: Fix missing <linux/stacktrace.h> include
  slub: reduce overhead of slub_debug
  slub: Add method to verify memory is not freed
  slub: Enable backtrace for create/delete points
  slab allocators: Provide generic description of alignment defines
  slab, slub, slob: Unify alignment definition
  slob/lockdep: Fix gfp flags passed to lockdep
This commit is contained in:
Linus Torvalds 2011-07-22 12:44:30 -07:00
commit f99b7880cb
7 changed files with 164 additions and 69 deletions

View File

@ -133,6 +133,26 @@ unsigned int kmem_cache_size(struct kmem_cache *);
#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH)
#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT)
/*
* Some archs want to perform DMA into kmalloc caches and need a guaranteed
* alignment larger than the alignment of a 64-bit integer.
* Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
*/
#ifdef ARCH_DMA_MINALIGN
#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
#else
#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
#endif
/*
* Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
* Intended for arches that get misalignment faults even for 64 bit integer
* aligned buffers.
*/
#ifndef ARCH_SLAB_MINALIGN
#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
#endif
/*
* Common kmalloc functions provided by all allocators
*/

View File

@ -17,32 +17,6 @@
#include <trace/events/kmem.h>
/*
* Enforce a minimum alignment for the kmalloc caches.
* Usually, the kmalloc caches are cache_line_size() aligned, except when
* DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned.
* Some archs want to perform DMA into kmalloc caches and need a guaranteed
* alignment larger than the alignment of a 64-bit integer.
* ARCH_KMALLOC_MINALIGN allows that.
* Note that increasing this value may disable some debug features.
*/
#ifdef ARCH_DMA_MINALIGN
#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
#else
#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
#endif
#ifndef ARCH_SLAB_MINALIGN
/*
* Enforce a minimum alignment for all caches.
* Intended for archs that get misalignment faults even for BYTES_PER_WORD
* aligned buffers. Includes ARCH_KMALLOC_MINALIGN.
* If possible: Do not enable this flag for CONFIG_DEBUG_SLAB, it disables
* some debug features.
*/
#define ARCH_SLAB_MINALIGN 0
#endif
/*
* struct kmem_cache
*
@ -50,21 +24,19 @@
*/
struct kmem_cache {
/* 1) per-cpu data, touched during every alloc/free */
struct array_cache *array[NR_CPUS];
/* 2) Cache tunables. Protected by cache_chain_mutex */
/* 1) Cache tunables. Protected by cache_chain_mutex */
unsigned int batchcount;
unsigned int limit;
unsigned int shared;
unsigned int buffer_size;
u32 reciprocal_buffer_size;
/* 3) touched by every alloc & free from the backend */
/* 2) touched by every alloc & free from the backend */
unsigned int flags; /* constant flags */
unsigned int num; /* # of objs per slab */
/* 4) cache_grow/shrink */
/* 3) cache_grow/shrink */
/* order of pgs per slab (2^n) */
unsigned int gfporder;
@ -80,11 +52,11 @@ struct kmem_cache {
/* constructor func */
void (*ctor)(void *obj);
/* 5) cache creation/removal */
/* 4) cache creation/removal */
const char *name;
struct list_head next;
/* 6) statistics */
/* 5) statistics */
#ifdef CONFIG_DEBUG_SLAB
unsigned long num_active;
unsigned long num_allocations;
@ -111,16 +83,18 @@ struct kmem_cache {
int obj_size;
#endif /* CONFIG_DEBUG_SLAB */
/* 6) per-cpu/per-node data, touched during every alloc/free */
/*
* We put nodelists[] at the end of kmem_cache, because we want to size
* this array to nr_node_ids slots instead of MAX_NUMNODES
* We put array[] at the end of kmem_cache, because we want to size
* this array to nr_cpu_ids slots instead of NR_CPUS
* (see kmem_cache_init())
* We still use [MAX_NUMNODES] and not [1] or [0] because cache_cache
* is statically defined, so we reserve the max number of nodes.
* We still use [NR_CPUS] and not [1] or [0] because cache_cache
* is statically defined, so we reserve the max number of cpus.
*/
struct kmem_list3 *nodelists[MAX_NUMNODES];
struct kmem_list3 **nodelists;
struct array_cache *array[NR_CPUS];
/*
* Do not add fields after nodelists[]
* Do not add fields after array[]
*/
};

View File

@ -1,16 +1,6 @@
#ifndef __LINUX_SLOB_DEF_H
#define __LINUX_SLOB_DEF_H
#ifdef ARCH_DMA_MINALIGN
#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
#else
#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long)
#endif
#ifndef ARCH_SLAB_MINALIGN
#define ARCH_SLAB_MINALIGN __alignof__(unsigned long)
#endif
void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
static __always_inline void *kmem_cache_alloc(struct kmem_cache *cachep,

View File

@ -113,16 +113,6 @@ struct kmem_cache {
#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
#ifdef ARCH_DMA_MINALIGN
#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
#else
#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
#endif
#ifndef ARCH_SLAB_MINALIGN
#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
#endif
/*
* Maximum kmalloc object size handled by SLUB. Larger object allocations
* are passed through to the page allocator. The page allocator "fastpath"
@ -228,6 +218,19 @@ kmalloc_order(size_t size, gfp_t flags, unsigned int order)
return ret;
}
/**
* Calling this on allocated memory will check that the memory
* is expected to be in use, and print warnings if not.
*/
#ifdef CONFIG_SLUB_DEBUG
extern bool verify_mem_not_deleted(const void *x);
#else
static inline bool verify_mem_not_deleted(const void *x)
{
return true;
}
#endif
#ifdef CONFIG_TRACING
extern void *
kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size);

View File

@ -574,7 +574,9 @@ static struct arraycache_init initarray_generic =
{ {0, BOOT_CPUCACHE_ENTRIES, 1, 0} };
/* internal cache of cache description objs */
static struct kmem_list3 *cache_cache_nodelists[MAX_NUMNODES];
static struct kmem_cache cache_cache = {
.nodelists = cache_cache_nodelists,
.batchcount = 1,
.limit = BOOT_CPUCACHE_ENTRIES,
.shared = 1,
@ -1492,11 +1494,10 @@ void __init kmem_cache_init(void)
cache_cache.nodelists[node] = &initkmem_list3[CACHE_CACHE + node];
/*
* struct kmem_cache size depends on nr_node_ids, which
* can be less than MAX_NUMNODES.
* struct kmem_cache size depends on nr_node_ids & nr_cpu_ids
*/
cache_cache.buffer_size = offsetof(struct kmem_cache, nodelists) +
nr_node_ids * sizeof(struct kmem_list3 *);
cache_cache.buffer_size = offsetof(struct kmem_cache, array[nr_cpu_ids]) +
nr_node_ids * sizeof(struct kmem_list3 *);
#if DEBUG
cache_cache.obj_size = cache_cache.buffer_size;
#endif
@ -2308,6 +2309,7 @@ kmem_cache_create (const char *name, size_t size, size_t align,
if (!cachep)
goto oops;
cachep->nodelists = (struct kmem_list3 **)&cachep->array[nr_cpu_ids];
#if DEBUG
cachep->obj_size = size;
@ -3153,12 +3155,11 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
objp += obj_offset(cachep);
if (cachep->ctor && cachep->flags & SLAB_POISON)
cachep->ctor(objp);
#if ARCH_SLAB_MINALIGN
if ((u32)objp & (ARCH_SLAB_MINALIGN-1)) {
if (ARCH_SLAB_MINALIGN &&
((unsigned long)objp & (ARCH_SLAB_MINALIGN-1))) {
printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n",
objp, ARCH_SLAB_MINALIGN);
objp, (int)ARCH_SLAB_MINALIGN);
}
#endif
return objp;
}
#else

View File

@ -482,6 +482,8 @@ void *__kmalloc_node(size_t size, gfp_t gfp, int node)
int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
void *ret;
gfp &= gfp_allowed_mask;
lockdep_trace_alloc(gfp);
if (size < PAGE_SIZE - align) {
@ -608,6 +610,10 @@ void *kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node)
{
void *b;
flags &= gfp_allowed_mask;
lockdep_trace_alloc(flags);
if (c->size < PAGE_SIZE) {
b = slob_alloc(c->size, flags, c->align, node);
trace_kmem_cache_alloc_node(_RET_IP_, b, c->size,

105
mm/slub.c
View File

@ -27,6 +27,7 @@
#include <linux/memory.h>
#include <linux/math64.h>
#include <linux/fault-inject.h>
#include <linux/stacktrace.h>
#include <trace/events/kmem.h>
@ -191,8 +192,12 @@ static LIST_HEAD(slab_caches);
/*
* Tracking user of a slab.
*/
#define TRACK_ADDRS_COUNT 16
struct track {
unsigned long addr; /* Called from address */
#ifdef CONFIG_STACKTRACE
unsigned long addrs[TRACK_ADDRS_COUNT]; /* Called from address */
#endif
int cpu; /* Was running on cpu */
int pid; /* Pid context */
unsigned long when; /* When did the operation occur */
@ -420,6 +425,24 @@ static void set_track(struct kmem_cache *s, void *object,
struct track *p = get_track(s, object, alloc);
if (addr) {
#ifdef CONFIG_STACKTRACE
struct stack_trace trace;
int i;
trace.nr_entries = 0;
trace.max_entries = TRACK_ADDRS_COUNT;
trace.entries = p->addrs;
trace.skip = 3;
save_stack_trace(&trace);
/* See rant in lockdep.c */
if (trace.nr_entries != 0 &&
trace.entries[trace.nr_entries - 1] == ULONG_MAX)
trace.nr_entries--;
for (i = trace.nr_entries; i < TRACK_ADDRS_COUNT; i++)
p->addrs[i] = 0;
#endif
p->addr = addr;
p->cpu = smp_processor_id();
p->pid = current->pid;
@ -444,6 +467,16 @@ static void print_track(const char *s, struct track *t)
printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n",
s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid);
#ifdef CONFIG_STACKTRACE
{
int i;
for (i = 0; i < TRACK_ADDRS_COUNT; i++)
if (t->addrs[i])
printk(KERN_ERR "\t%pS\n", (void *)t->addrs[i]);
else
break;
}
#endif
}
static void print_tracking(struct kmem_cache *s, void *object)
@ -557,10 +590,10 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
memset(p + s->objsize, val, s->inuse - s->objsize);
}
static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
static u8 *check_bytes8(u8 *start, u8 value, unsigned int bytes)
{
while (bytes) {
if (*start != (u8)value)
if (*start != value)
return start;
start++;
bytes--;
@ -568,6 +601,38 @@ static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
return NULL;
}
static u8 *check_bytes(u8 *start, u8 value, unsigned int bytes)
{
u64 value64;
unsigned int words, prefix;
if (bytes <= 16)
return check_bytes8(start, value, bytes);
value64 = value | value << 8 | value << 16 | value << 24;
value64 = value64 | value64 << 32;
prefix = 8 - ((unsigned long)start) % 8;
if (prefix) {
u8 *r = check_bytes8(start, value, prefix);
if (r)
return r;
start += prefix;
bytes -= prefix;
}
words = bytes / 8;
while (words) {
if (*(u64 *)start != value64)
return check_bytes8(start, value, 8);
start += 8;
words--;
}
return check_bytes8(start, value, bytes % 8);
}
static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
void *from, void *to)
{
@ -2928,6 +2993,42 @@ size_t ksize(const void *object)
}
EXPORT_SYMBOL(ksize);
#ifdef CONFIG_SLUB_DEBUG
bool verify_mem_not_deleted(const void *x)
{
struct page *page;
void *object = (void *)x;
unsigned long flags;
bool rv;
if (unlikely(ZERO_OR_NULL_PTR(x)))
return false;
local_irq_save(flags);
page = virt_to_head_page(x);
if (unlikely(!PageSlab(page))) {
/* maybe it was from stack? */
rv = true;
goto out_unlock;
}
slab_lock(page);
if (on_freelist(page->slab, page, object)) {
object_err(page->slab, page, object, "Object is on free-list");
rv = false;
} else {
rv = true;
}
slab_unlock(page);
out_unlock:
local_irq_restore(flags);
return rv;
}
EXPORT_SYMBOL(verify_mem_not_deleted);
#endif
void kfree(const void *x)
{
struct page *page;