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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-22 09:36:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-22 09:36:23 -0700
commit14577beb8293c187a12d2e78ac6250d5dcec2190 (patch)
treecca4d8feba497870e3a5936ba2a65c68ce4ddf6b
parent09b9cc44c942256026bf7a63fec2155b8f488899 (diff)
parente8c500c2b64b6e237e67ecba7249e72363c47047 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6: slub: Dont define useless label in the !CONFIG_CMPXCHG_LOCAL case slab,rcu: don't assume the size of struct rcu_head slub,rcu: don't assume the size of struct rcu_head slub: automatically reserve bytes at the end of slab Lockless (and preemptless) fastpaths for slub slub: Get rid of slab_free_hook_irq() slub: min_partial needs to be in first cacheline slub: fix ksize() build error slub: fix kmemcheck calls to match ksize() hints Revert "slab: Fix missing DEBUG_SLAB last user" mm: Remove support for kmem_cache_name()
-rw-r--r--include/linux/slab.h1
-rw-r--r--include/linux/slub_def.h8
-rw-r--r--mm/slab.c55
-rw-r--r--mm/slob.c6
-rw-r--r--mm/slub.c366
5 files changed, 333 insertions, 103 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h
index fa9086647eb7..ad4dd1c8d30a 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -105,7 +105,6 @@ void kmem_cache_destroy(struct kmem_cache *);
int kmem_cache_shrink(struct kmem_cache *);
void kmem_cache_free(struct kmem_cache *, void *);
unsigned int kmem_cache_size(struct kmem_cache *);
-const char *kmem_cache_name(struct kmem_cache *);
/*
* Please use this macro to create slab caches. Simply specify the
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 8b6e8ae5d5ca..90fbb6d87e11 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -35,7 +35,10 @@ enum stat_item {
NR_SLUB_STAT_ITEMS };
struct kmem_cache_cpu {
- void **freelist; /* Pointer to first free per cpu object */
+ void **freelist; /* Pointer to next available object */
+#ifdef CONFIG_CMPXCHG_LOCAL
+ unsigned long tid; /* Globally unique transaction id */
+#endif
struct page *page; /* The slab from which we are allocating */
int node; /* The node of the page (or -1 for debug) */
#ifdef CONFIG_SLUB_STATS
@@ -70,6 +73,7 @@ struct kmem_cache {
struct kmem_cache_cpu __percpu *cpu_slab;
/* Used for retriving partial slabs etc */
unsigned long flags;
+ unsigned long min_partial;
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. */
@@ -83,7 +87,7 @@ struct kmem_cache {
void (*ctor)(void *);
int inuse; /* Offset to metadata */
int align; /* Alignment */
- unsigned long min_partial;
+ int reserved; /* Reserved bytes at the end of slabs */
const char *name; /* Name (only for display!) */
struct list_head list; /* List of slab caches */
#ifdef CONFIG_SYSFS
diff --git a/mm/slab.c b/mm/slab.c
index 37961d1f584f..a18ba57517af 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -191,22 +191,6 @@ typedef unsigned int kmem_bufctl_t;
#define SLAB_LIMIT (((kmem_bufctl_t)(~0U))-3)
/*
- * struct slab
- *
- * Manages the objs in a slab. Placed either at the beginning of mem allocated
- * for a slab, or allocated from an general cache.
- * Slabs are chained into three list: fully used, partial, fully free slabs.
- */
-struct slab {
- struct list_head list;
- unsigned long colouroff;
- void *s_mem; /* including colour offset */
- unsigned int inuse; /* num of objs active in slab */
- kmem_bufctl_t free;
- unsigned short nodeid;
-};
-
-/*
* struct slab_rcu
*
* slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to
@@ -219,8 +203,6 @@ struct slab {
*
* rcu_read_lock before reading the address, then rcu_read_unlock after
* taking the spinlock within the structure expected at that address.
- *
- * We assume struct slab_rcu can overlay struct slab when destroying.
*/
struct slab_rcu {
struct rcu_head head;
@@ -229,6 +211,27 @@ struct slab_rcu {
};
/*
+ * struct slab
+ *
+ * Manages the objs in a slab. Placed either at the beginning of mem allocated
+ * for a slab, or allocated from an general cache.
+ * Slabs are chained into three list: fully used, partial, fully free slabs.
+ */
+struct slab {
+ union {
+ struct {
+ struct list_head list;
+ unsigned long colouroff;
+ void *s_mem; /* including colour offset */
+ unsigned int inuse; /* num of objs active in slab */
+ kmem_bufctl_t free;
+ unsigned short nodeid;
+ };
+ struct slab_rcu __slab_cover_slab_rcu;
+ };
+};
+
+/*
* struct array_cache
*
* Purpose:
@@ -2147,8 +2150,6 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
*
* @name must be valid until the cache is destroyed. This implies that
* the module calling this has to destroy the cache before getting unloaded.
- * Note that kmem_cache_name() is not guaranteed to return the same pointer,
- * therefore applications must manage it themselves.
*
* The flags are
*
@@ -2288,8 +2289,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
if (ralign < align) {
ralign = align;
}
- /* disable debug if not aligning with REDZONE_ALIGN */
- if (ralign & (__alignof__(unsigned long long) - 1))
+ /* disable debug if necessary */
+ if (ralign > __alignof__(unsigned long long))
flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
/*
* 4) Store it.
@@ -2315,8 +2316,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
*/
if (flags & SLAB_RED_ZONE) {
/* add space for red zone words */
- cachep->obj_offset += align;
- size += align + sizeof(unsigned long long);
+ cachep->obj_offset += sizeof(unsigned long long);
+ size += 2 * sizeof(unsigned long long);
}
if (flags & SLAB_STORE_USER) {
/* user store requires one word storage behind the end of
@@ -3840,12 +3841,6 @@ unsigned int kmem_cache_size(struct kmem_cache *cachep)
}
EXPORT_SYMBOL(kmem_cache_size);
-const char *kmem_cache_name(struct kmem_cache *cachep)
-{
- return cachep->name;
-}
-EXPORT_SYMBOL_GPL(kmem_cache_name);
-
/*
* This initializes kmem_list3 or resizes various caches for all nodes.
*/
diff --git a/mm/slob.c b/mm/slob.c
index 3588eaaef726..46e0aee33a23 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -666,12 +666,6 @@ unsigned int kmem_cache_size(struct kmem_cache *c)
}
EXPORT_SYMBOL(kmem_cache_size);
-const char *kmem_cache_name(struct kmem_cache *c)
-{
- return c->name;
-}
-EXPORT_SYMBOL(kmem_cache_name);
-
int kmem_cache_shrink(struct kmem_cache *d)
{
return 0;
diff --git a/mm/slub.c b/mm/slub.c
index e15aa7f193c9..7e4f835e32ab 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -281,11 +281,40 @@ static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
return (p - addr) / s->size;
}
+static inline size_t slab_ksize(const struct kmem_cache *s)
+{
+#ifdef CONFIG_SLUB_DEBUG
+ /*
+ * Debugging requires use of the padding between object
+ * and whatever may come after it.
+ */
+ if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
+ return s->objsize;
+
+#endif
+ /*
+ * If we have the need to store the freelist pointer
+ * back there or track user information then we can
+ * only use the space before that information.
+ */
+ if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
+ return s->inuse;
+ /*
+ * Else we can use all the padding etc for the allocation
+ */
+ return s->size;
+}
+
+static inline int order_objects(int order, unsigned long size, int reserved)
+{
+ return ((PAGE_SIZE << order) - reserved) / size;
+}
+
static inline struct kmem_cache_order_objects oo_make(int order,
- unsigned long size)
+ unsigned long size, int reserved)
{
struct kmem_cache_order_objects x = {
- (order << OO_SHIFT) + (PAGE_SIZE << order) / size
+ (order << OO_SHIFT) + order_objects(order, size, reserved)
};
return x;
@@ -617,7 +646,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page)
return 1;
start = page_address(page);
- length = (PAGE_SIZE << compound_order(page));
+ length = (PAGE_SIZE << compound_order(page)) - s->reserved;
end = start + length;
remainder = length % s->size;
if (!remainder)
@@ -698,7 +727,7 @@ static int check_slab(struct kmem_cache *s, struct page *page)
return 0;
}
- maxobj = (PAGE_SIZE << compound_order(page)) / s->size;
+ maxobj = order_objects(compound_order(page), s->size, s->reserved);
if (page->objects > maxobj) {
slab_err(s, page, "objects %u > max %u",
s->name, page->objects, maxobj);
@@ -748,7 +777,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
nr++;
}
- max_objects = (PAGE_SIZE << compound_order(page)) / s->size;
+ max_objects = order_objects(compound_order(page), s->size, s->reserved);
if (max_objects > MAX_OBJS_PER_PAGE)
max_objects = MAX_OBJS_PER_PAGE;
@@ -800,21 +829,31 @@ static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, void *object)
{
flags &= gfp_allowed_mask;
- kmemcheck_slab_alloc(s, flags, object, s->objsize);
+ kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
kmemleak_alloc_recursive(object, s->objsize, 1, s->flags, flags);
}
static inline void slab_free_hook(struct kmem_cache *s, void *x)
{
kmemleak_free_recursive(x, s->flags);
-}
-static inline void slab_free_hook_irq(struct kmem_cache *s, void *object)
-{
- kmemcheck_slab_free(s, object, s->objsize);
- debug_check_no_locks_freed(object, s->objsize);
- if (!(s->flags & SLAB_DEBUG_OBJECTS))
- debug_check_no_obj_freed(object, s->objsize);
+ /*
+ * Trouble is that we may no longer disable interupts in the fast path
+ * So in order to make the debug calls that expect irqs to be
+ * disabled we need to disable interrupts temporarily.
+ */
+#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP)
+ {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ kmemcheck_slab_free(s, x, s->objsize);
+ debug_check_no_locks_freed(x, s->objsize);
+ if (!(s->flags & SLAB_DEBUG_OBJECTS))
+ debug_check_no_obj_freed(x, s->objsize);
+ local_irq_restore(flags);
+ }
+#endif
}
/*
@@ -1101,9 +1140,6 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
static inline void slab_free_hook(struct kmem_cache *s, void *x) {}
-static inline void slab_free_hook_irq(struct kmem_cache *s,
- void *object) {}
-
#endif /* CONFIG_SLUB_DEBUG */
/*
@@ -1249,21 +1285,38 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
__free_pages(page, order);
}
+#define need_reserve_slab_rcu \
+ (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
+
static void rcu_free_slab(struct rcu_head *h)
{
struct page *page;
- page = container_of((struct list_head *)h, struct page, lru);
+ if (need_reserve_slab_rcu)
+ page = virt_to_head_page(h);
+ else
+ page = container_of((struct list_head *)h, struct page, lru);
+
__free_slab(page->slab, page);
}
static void free_slab(struct kmem_cache *s, struct page *page)
{
if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) {
- /*
- * RCU free overloads the RCU head over the LRU
- */
- struct rcu_head *head = (void *)&page->lru;
+ struct rcu_head *head;
+
+ if (need_reserve_slab_rcu) {
+ int order = compound_order(page);
+ int offset = (PAGE_SIZE << order) - s->reserved;
+
+ VM_BUG_ON(s->reserved != sizeof(*head));
+ head = page_address(page) + offset;
+ } else {
+ /*
+ * RCU free overloads the RCU head over the LRU
+ */
+ head = (void *)&page->lru;
+ }
call_rcu(head, rcu_free_slab);
} else
@@ -1487,6 +1540,77 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
}
}
+#ifdef CONFIG_CMPXCHG_LOCAL
+#ifdef CONFIG_PREEMPT
+/*
+ * Calculate the next globally unique transaction for disambiguiation
+ * during cmpxchg. The transactions start with the cpu number and are then
+ * incremented by CONFIG_NR_CPUS.
+ */
+#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS)
+#else
+/*
+ * No preemption supported therefore also no need to check for
+ * different cpus.
+ */
+#define TID_STEP 1
+#endif
+
+static inline unsigned long next_tid(unsigned long tid)
+{
+ return tid + TID_STEP;
+}
+
+static inline unsigned int tid_to_cpu(unsigned long tid)
+{
+ return tid % TID_STEP;
+}
+
+static inline unsigned long tid_to_event(unsigned long tid)
+{
+ return tid / TID_STEP;
+}
+
+static inline unsigned int init_tid(int cpu)
+{
+ return cpu;
+}
+
+static inline void note_cmpxchg_failure(const char *n,
+ const struct kmem_cache *s, unsigned long tid)
+{
+#ifdef SLUB_DEBUG_CMPXCHG
+ unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid);
+
+ printk(KERN_INFO "%s %s: cmpxchg redo ", n, s->name);
+
+#ifdef CONFIG_PREEMPT
+ if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))
+ printk("due to cpu change %d -> %d\n",
+ tid_to_cpu(tid), tid_to_cpu(actual_tid));
+ else
+#endif
+ if (tid_to_event(tid) != tid_to_event(actual_tid))
+ printk("due to cpu running other code. Event %ld->%ld\n",
+ tid_to_event(tid), tid_to_event(actual_tid));
+ else
+ printk("for unknown reason: actual=%lx was=%lx target=%lx\n",
+ actual_tid, tid, next_tid(tid));
+#endif
+}
+
+#endif
+
+void init_kmem_cache_cpus(struct kmem_cache *s)
+{
+#if defined(CONFIG_CMPXCHG_LOCAL) && defined(CONFIG_PREEMPT)
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu);
+#endif
+
+}
/*
* Remove the cpu slab
*/
@@ -1518,6 +1642,9 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
page->inuse--;
}
c->page = NULL;
+#ifdef CONFIG_CMPXCHG_LOCAL
+ c->tid = next_tid(c->tid);
+#endif
unfreeze_slab(s, page, tail);
}
@@ -1652,6 +1779,19 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
{
void **object;
struct page *new;
+#ifdef CONFIG_CMPXCHG_LOCAL
+ unsigned long flags;
+
+ local_irq_save(flags);
+#ifdef CONFIG_PREEMPT
+ /*
+ * We may have been preempted and rescheduled on a different
+ * cpu before disabling interrupts. Need to reload cpu area
+ * pointer.
+ */
+ c = this_cpu_ptr(s->cpu_slab);
+#endif
+#endif
/* We handle __GFP_ZERO in the caller */
gfpflags &= ~__GFP_ZERO;
@@ -1678,6 +1818,10 @@ load_freelist:
c->node = page_to_nid(c->page);
unlock_out:
slab_unlock(c->page);
+#ifdef CONFIG_CMPXCHG_LOCAL
+ c->tid = next_tid(c->tid);
+ local_irq_restore(flags);
+#endif
stat(s, ALLOC_SLOWPATH);
return object;
@@ -1739,23 +1883,76 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,
{
void **object;
struct kmem_cache_cpu *c;
+#ifdef CONFIG_CMPXCHG_LOCAL
+ unsigned long tid;
+#else
unsigned long flags;
+#endif
if (slab_pre_alloc_hook(s, gfpflags))
return NULL;
+#ifndef CONFIG_CMPXCHG_LOCAL
local_irq_save(flags);
+#else
+redo:
+#endif
+
+ /*
+ * Must read kmem_cache cpu data via this cpu ptr. Preemption is
+ * enabled. We may switch back and forth between cpus while
+ * reading from one cpu area. That does not matter as long
+ * as we end up on the original cpu again when doing the cmpxchg.
+ */
c = __this_cpu_ptr(s->cpu_slab);
+
+#ifdef CONFIG_CMPXCHG_LOCAL
+ /*
+ * The transaction ids are globally unique per cpu and per operation on
+ * a per cpu queue. Thus they can be guarantee that the cmpxchg_double
+ * occurs on the right processor and that there was no operation on the
+ * linked list in between.
+ */
+ tid = c->tid;
+ barrier();
+#endif
+
object = c->freelist;
if (unlikely(!object || !node_match(c, node)))
object = __slab_alloc(s, gfpflags, node, addr, c);
else {
+#ifdef CONFIG_CMPXCHG_LOCAL
+ /*
+ * The cmpxchg will only match if there was no additonal
+ * operation and if we are on the right processor.
+ *
+ * The cmpxchg does the following atomically (without lock semantics!)
+ * 1. Relocate first pointer to the current per cpu area.
+ * 2. Verify that tid and freelist have not been changed
+ * 3. If they were not changed replace tid and freelist
+ *
+ * Since this is without lock semantics the protection is only against
+ * code executing on this cpu *not* from access by other cpus.
+ */
+ if (unlikely(!this_cpu_cmpxchg_double(
+ s->cpu_slab->freelist, s->cpu_slab->tid,
+ object, tid,
+ get_freepointer(s, object), next_tid(tid)))) {
+
+ note_cmpxchg_failure("slab_alloc", s, tid);
+ goto redo;
+ }
+#else
c->freelist = get_freepointer(s, object);
+#endif
stat(s, ALLOC_FASTPATH);
}
+
+#ifndef CONFIG_CMPXCHG_LOCAL
local_irq_restore(flags);
+#endif
if (unlikely(gfpflags & __GFP_ZERO) && object)
memset(object, 0, s->objsize);
@@ -1833,9 +2030,13 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
{
void *prior;
void **object = (void *)x;
+#ifdef CONFIG_CMPXCHG_LOCAL
+ unsigned long flags;
- stat(s, FREE_SLOWPATH);
+ local_irq_save(flags);
+#endif
slab_lock(page);
+ stat(s, FREE_SLOWPATH);
if (kmem_cache_debug(s))
goto debug;
@@ -1865,6 +2066,9 @@ checks_ok:
out_unlock:
slab_unlock(page);
+#ifdef CONFIG_CMPXCHG_LOCAL
+ local_irq_restore(flags);
+#endif
return;
slab_empty:
@@ -1876,6 +2080,9 @@ slab_empty:
stat(s, FREE_REMOVE_PARTIAL);
}
slab_unlock(page);
+#ifdef CONFIG_CMPXCHG_LOCAL
+ local_irq_restore(flags);
+#endif
stat(s, FREE_SLAB);
discard_slab(s, page);
return;
@@ -1902,23 +2109,56 @@ static __always_inline void slab_free(struct kmem_cache *s,
{
void **object = (void *)x;
struct kmem_cache_cpu *c;
+#ifdef CONFIG_CMPXCHG_LOCAL
+ unsigned long tid;
+#else
unsigned long flags;
+#endif
slab_free_hook(s, x);
+#ifndef CONFIG_CMPXCHG_LOCAL
local_irq_save(flags);
+
+#else
+redo:
+#endif
+
+ /*
+ * Determine the currently cpus per cpu slab.
+ * The cpu may change afterward. However that does not matter since
+ * data is retrieved via this pointer. If we are on the same cpu
+ * during the cmpxchg then the free will succedd.
+ */
c = __this_cpu_ptr(s->cpu_slab);
- slab_free_hook_irq(s, x);
+#ifdef CONFIG_CMPXCHG_LOCAL
+ tid = c->tid;
+ barrier();
+#endif
if (likely(page == c->page && c->node != NUMA_NO_NODE)) {
set_freepointer(s, object, c->freelist);
+
+#ifdef CONFIG_CMPXCHG_LOCAL
+ if (unlikely(!this_cpu_cmpxchg_double(
+ s->cpu_slab->freelist, s->cpu_slab->tid,
+ c->freelist, tid,
+ object, next_tid(tid)))) {
+
+ note_cmpxchg_failure("slab_free", s, tid);
+ goto redo;
+ }
+#else
c->freelist = object;
+#endif
stat(s, FREE_FASTPATH);
} else
__slab_free(s, page, x, addr);
+#ifndef CONFIG_CMPXCHG_LOCAL
local_irq_restore(flags);
+#endif
}
void kmem_cache_free(struct kmem_cache *s, void *x)
@@ -1988,13 +2228,13 @@ static int slub_nomerge;
* the smallest order which will fit the object.
*/
static inline int slab_order(int size, int min_objects,
- int max_order, int fract_leftover)
+ int max_order, int fract_leftover, int reserved)
{
int order;
int rem;
int min_order = slub_min_order;
- if ((PAGE_SIZE << min_order) / size > MAX_OBJS_PER_PAGE)
+ if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE)
return get_order(size * MAX_OBJS_PER_PAGE) - 1;
for (order = max(min_order,
@@ -2003,10 +2243,10 @@ static inline int slab_order(int size, int min_objects,
unsigned long slab_size = PAGE_SIZE << order;
- if (slab_size < min_objects * size)
+ if (slab_size < min_objects * size + reserved)
continue;
- rem = slab_size % size;
+ rem = (slab_size - reserved) % size;
if (rem <= slab_size / fract_leftover)
break;
@@ -2016,7 +2256,7 @@ static inline int slab_order(int size, int min_objects,
return order;
}
-static inline int calculate_order(int size)
+static inline int calculate_order(int size, int reserved)
{
int order;
int min_objects;
@@ -2034,14 +2274,14 @@ static inline int calculate_order(int size)
min_objects = slub_min_objects;
if (!min_objects)
min_objects = 4 * (fls(nr_cpu_ids) + 1);
- max_objects = (PAGE_SIZE << slub_max_order)/size;
+ max_objects = order_objects(slub_max_order, size, reserved);
min_objects = min(min_objects, max_objects);
while (min_objects > 1) {
fraction = 16;
while (fraction >= 4) {
order = slab_order(size, min_objects,
- slub_max_order, fraction);
+ slub_max_order, fraction, reserved);
if (order <= slub_max_order)
return order;
fraction /= 2;
@@ -2053,14 +2293,14 @@ static inline int calculate_order(int size)
* We were unable to place multiple objects in a slab. Now
* lets see if we can place a single object there.
*/
- order = slab_order(size, 1, slub_max_order, 1);
+ order = slab_order(size, 1, slub_max_order, 1, reserved);
if (order <= slub_max_order)
return order;
/*
* Doh this slab cannot be placed using slub_max_order.
*/
- order = slab_order(size, 1, MAX_ORDER, 1);
+ order = slab_order(size, 1, MAX_ORDER, 1, reserved);
if (order < MAX_ORDER)
return order;
return -ENOSYS;
@@ -2110,9 +2350,23 @@ static inline int alloc_kmem_cache_cpus(struct kmem_cache *s)
BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE <
SLUB_PAGE_SHIFT * sizeof(struct kmem_cache_cpu));
+#ifdef CONFIG_CMPXCHG_LOCAL
+ /*
+ * Must align to double word boundary for the double cmpxchg instructions
+ * to work.
+ */
+ s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), 2 * sizeof(void *));
+#else
+ /* Regular alignment is sufficient */
s->cpu_slab = alloc_percpu(struct kmem_cache_cpu);
+#endif
- return s->cpu_slab != NULL;
+ if (!s->cpu_slab)
+ return 0;
+
+ init_kmem_cache_cpus(s);
+
+ return 1;
}
static struct kmem_cache *kmem_cache_node;
@@ -2311,7 +2565,7 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
if (forced_order >= 0)
order = forced_order;
else
- order = calculate_order(size);
+ order = calculate_order(size, s->reserved);
if (order < 0)
return 0;
@@ -2329,8 +2583,8 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
/*
* Determine the number of objects per slab
*/
- s->oo = oo_make(order, size);
- s->min = oo_make(get_order(size), size);
+ s->oo = oo_make(order, size, s->reserved);
+ s->min = oo_make(get_order(size), size, s->reserved);
if (oo_objects(s->oo) > oo_objects(s->max))
s->max = s->oo;
@@ -2349,6 +2603,10 @@ static int kmem_cache_open(struct kmem_cache *s,
s->objsize = size;
s->align = align;
s->flags = kmem_cache_flags(size, flags, name, ctor);
+ s->reserved = 0;
+
+ if (need_reserve_slab_rcu && (s->flags & SLAB_DESTROY_BY_RCU))
+ s->reserved = sizeof(struct rcu_head);
if (!calculate_sizes(s, -1))
goto error;
@@ -2399,12 +2657,6 @@ unsigned int kmem_cache_size(struct kmem_cache *s)
}
EXPORT_SYMBOL(kmem_cache_size);
-const char *kmem_cache_name(struct kmem_cache *s)
-{
- return s->name;
-}
-EXPORT_SYMBOL(kmem_cache_name);
-
static void list_slab_objects(struct kmem_cache *s, struct page *page,
const char *text)
{
@@ -2696,7 +2948,6 @@ EXPORT_SYMBOL(__kmalloc_node);
size_t ksize(const void *object)
{
struct page *page;
- struct kmem_cache *s;
if (unlikely(object == ZERO_SIZE_PTR))
return 0;
@@ -2707,28 +2958,8 @@ size_t ksize(const void *object)
WARN_ON(!PageCompound(page));
return PAGE_SIZE << compound_order(page);
}
- s = page->slab;
-#ifdef CONFIG_SLUB_DEBUG
- /*
- * Debugging requires use of the padding between object
- * and whatever may come after it.
- */
- if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
- return s->objsize;
-
-#endif
- /*
- * If we have the need to store the freelist pointer
- * back there or track user information then we can
- * only use the space before that information.
- */
- if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
- return s->inuse;
- /*
- * Else we can use all the padding etc for the allocation
- */
- return s->size;
+ return slab_ksize(page->slab);
}
EXPORT_SYMBOL(ksize);
@@ -4017,6 +4248,12 @@ static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
}
SLAB_ATTR_RO(destroy_by_rcu);
+static ssize_t reserved_show(struct kmem_cache *s, char *buf)
+{
+ return sprintf(buf, "%d\n", s->reserved);
+}
+SLAB_ATTR_RO(reserved);
+
#ifdef CONFIG_SLUB_DEBUG
static ssize_t slabs_show(struct kmem_cache *s, char *buf)
{
@@ -4303,6 +4540,7 @@ static struct attribute *slab_attrs[] = {
&reclaim_account_attr.attr,
&destroy_by_rcu_attr.attr,
&shrink_attr.attr,
+ &reserved_attr.attr,
#ifdef CONFIG_SLUB_DEBUG
&total_objects_attr.attr,
&slabs_attr.attr,