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Commit ea982d9f authored by Pekka Enberg's avatar Pekka Enberg
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Merge branch 'slab/struct-page' into slab/next

parents d56791b3 7e007355
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Showing with 243 additions and 365 deletions
include/linux/mm_types.h
View file @ ea982d9f
......@@ -42,6 +42,7 @@ struct page {
/* First double word block */
unsigned long flags; /* Atomic flags, some possibly
* updated asynchronously */
union {
struct address_space *mapping; /* If low bit clear, points to
* inode address_space, or NULL.
* If page mapped as anonymous
......@@ -49,11 +50,14 @@ struct page {
* it points to anon_vma object:
* see PAGE_MAPPING_ANON below.
*/
void *s_mem; /* slab first object */
};
/* Second double word */
struct {
union {
pgoff_t index; /* Our offset within mapping. */
void *freelist; /* slub/slob first free object */
void *freelist; /* sl[aou]b first free object */
bool pfmemalloc; /* If set by the page allocator,
* ALLOC_NO_WATERMARKS was set
* and the low watermark was not
......@@ -109,6 +113,7 @@ struct page {
};
atomic_t _count; /* Usage count, see below. */
};
unsigned int active; /* SLAB */
};
};
......@@ -130,6 +135,9 @@ struct page {
struct list_head list; /* slobs list of pages */
struct slab *slab_page; /* slab fields */
struct rcu_head rcu_head; /* Used by SLAB
* when destroying via RCU
*/
};
/* Remainder is not double word aligned */
......
include/linux/slab.h
View file @ ea982d9f
......@@ -51,7 +51,14 @@
* }
* rcu_read_unlock();
*
* See also the comment on struct slab_rcu in mm/slab.c.
* This is useful if we need to approach a kernel structure obliquely,
* from its address obtained without the usual locking. We can lock
* the structure to stabilize it and check it's still at the given address,
* only if we can be sure that the memory has not been meanwhile reused
* for some other kind of object (which our subsystem's lock might corrupt).
*
* rcu_read_lock before reading the address, then rcu_read_unlock after
* taking the spinlock within the structure expected at that address.
*/
#define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */
#define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */
......
include/linux/slab_def.h
View file @ ea982d9f
......@@ -41,8 +41,8 @@ struct kmem_cache {
size_t colour; /* cache colouring range */
unsigned int colour_off; /* colour offset */
struct kmem_cache *slabp_cache;
unsigned int slab_size;
struct kmem_cache *freelist_cache;
unsigned int freelist_size;
/* constructor func */
void (*ctor)(void *obj);
......
mm/slab.c
View file @ ea982d9f
......@@ -163,72 +163,6 @@
*/
static bool pfmemalloc_active __read_mostly;
/*
* kmem_bufctl_t:
*
* Bufctl's are used for linking objs within a slab
* linked offsets.
*
* This implementation relies on "struct page" for locating the cache &
* slab an object belongs to.
* This allows the bufctl structure to be small (one int), but limits
* the number of objects a slab (not a cache) can contain when off-slab
* bufctls are used. The limit is the size of the largest general cache
* that does not use off-slab slabs.
* For 32bit archs with 4 kB pages, is this 56.
* This is not serious, as it is only for large objects, when it is unwise
* to have too many per slab.
* Note: This limit can be raised by introducing a general cache whose size
* is less than 512 (PAGE_SIZE<<3), but greater than 256.
*/
typedef unsigned int kmem_bufctl_t;
#define BUFCTL_END (((kmem_bufctl_t)(~0U))-0)
#define BUFCTL_FREE (((kmem_bufctl_t)(~0U))-1)
#define BUFCTL_ACTIVE (((kmem_bufctl_t)(~0U))-2)
#define SLAB_LIMIT (((kmem_bufctl_t)(~0U))-3)
/*
* struct slab_rcu
*
* slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to
* arrange for kmem_freepages to be called via RCU. This is useful if
* we need to approach a kernel structure obliquely, from its address
* obtained without the usual locking. We can lock the structure to
* stabilize it and check it's still at the given address, only if we
* can be sure that the memory has not been meanwhile reused for some
* other kind of object (which our subsystem's lock might corrupt).
*
* rcu_read_lock before reading the address, then rcu_read_unlock after
* taking the spinlock within the structure expected at that address.
*/
struct slab_rcu {
struct rcu_head head;
struct kmem_cache *cachep;
void *addr;
};
/*
* 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
*
......@@ -456,18 +390,10 @@ static inline struct kmem_cache *virt_to_cache(const void *obj)
return page->slab_cache;
}
static inline struct slab *virt_to_slab(const void *obj)
{
struct page *page = virt_to_head_page(obj);
VM_BUG_ON(!PageSlab(page));
return page->slab_page;
}
static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab,
static inline void *index_to_obj(struct kmem_cache *cache, struct page *page,
unsigned int idx)
{
return slab->s_mem + cache->size * idx;
return page->s_mem + cache->size * idx;
}
/*
......@@ -477,9 +403,9 @@ static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab,
* reciprocal_divide(offset, cache->reciprocal_buffer_size)
*/
static inline unsigned int obj_to_index(const struct kmem_cache *cache,
const struct slab *slab, void *obj)
const struct page *page, void *obj)
{
u32 offset = (obj - slab->s_mem);
u32 offset = (obj - page->s_mem);
return reciprocal_divide(offset, cache->reciprocal_buffer_size);
}
......@@ -641,7 +567,7 @@ static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep)
static size_t slab_mgmt_size(size_t nr_objs, size_t align)
{
return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align);
return ALIGN(nr_objs * sizeof(unsigned int), align);
}
/*
......@@ -660,8 +586,7 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size,
* on it. For the latter case, the memory allocated for a
* slab is used for:
*
* - The struct slab
* - One kmem_bufctl_t for each object
* - One unsigned int for each object
* - Padding to respect alignment of @align
* - @buffer_size bytes for each object
*
......@@ -674,8 +599,6 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size,
mgmt_size = 0;
nr_objs = slab_size / buffer_size;
if (nr_objs > SLAB_LIMIT)
nr_objs = SLAB_LIMIT;
} else {
/*
* Ignore padding for the initial guess. The padding
......@@ -685,8 +608,7 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size,
* into the memory allocation when taking the padding
* into account.
*/
nr_objs = (slab_size - sizeof(struct slab)) /
(buffer_size + sizeof(kmem_bufctl_t));
nr_objs = (slab_size) / (buffer_size + sizeof(unsigned int));
/*
* This calculated number will be either the right
......@@ -696,9 +618,6 @@ static void cache_estimate(unsigned long gfporder, size_t buffer_size,
> slab_size)
nr_objs--;
if (nr_objs > SLAB_LIMIT)
nr_objs = SLAB_LIMIT;
mgmt_size = slab_mgmt_size(nr_objs, align);
}
*num = nr_objs;
......@@ -829,10 +748,8 @@ static struct array_cache *alloc_arraycache(int node, int entries,
return nc;
}
static inline bool is_slab_pfmemalloc(struct slab *slabp)
static inline bool is_slab_pfmemalloc(struct page *page)
{
struct page *page = virt_to_page(slabp->s_mem);
return PageSlabPfmemalloc(page);
}
......@@ -841,23 +758,23 @@ static void recheck_pfmemalloc_active(struct kmem_cache *cachep,
struct array_cache *ac)
{
struct kmem_cache_node *n = cachep->node[numa_mem_id()];
struct slab *slabp;
struct page *page;
unsigned long flags;
if (!pfmemalloc_active)
return;
spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(slabp, &n->slabs_full, list)
if (is_slab_pfmemalloc(slabp))
list_for_each_entry(page, &n->slabs_full, lru)
if (is_slab_pfmemalloc(page))
goto out;
list_for_each_entry(slabp, &n->slabs_partial, list)
if (is_slab_pfmemalloc(slabp))
list_for_each_entry(page, &n->slabs_partial, lru)
if (is_slab_pfmemalloc(page))
goto out;
list_for_each_entry(slabp, &n->slabs_free, list)
if (is_slab_pfmemalloc(slabp))
list_for_each_entry(page, &n->slabs_free, lru)
if (is_slab_pfmemalloc(page))
goto out;
pfmemalloc_active = false;
......@@ -897,8 +814,8 @@ static void *__ac_get_obj(struct kmem_cache *cachep, struct array_cache *ac,
*/
n = cachep->node[numa_mem_id()];
if (!list_empty(&n->slabs_free) && force_refill) {
struct slab *slabp = virt_to_slab(objp);
ClearPageSlabPfmemalloc(virt_to_head_page(slabp->s_mem));
struct page *page = virt_to_head_page(objp);
ClearPageSlabPfmemalloc(page);
clear_obj_pfmemalloc(&objp);
recheck_pfmemalloc_active(cachep, ac);
return objp;
......@@ -1099,8 +1016,7 @@ static void drain_alien_cache(struct kmem_cache *cachep,
static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
{
struct slab *slabp = virt_to_slab(objp);
int nodeid = slabp->nodeid;
int nodeid = page_to_nid(virt_to_page(objp));
struct kmem_cache_node *n;
struct array_cache *alien = NULL;
int node;
......@@ -1111,7 +1027,7 @@ static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
* Make sure we are not freeing a object from another node to the array
* cache on this cpu.
*/
if (likely(slabp->nodeid == node))
if (likely(nodeid == node))
return 0;
n = cachep->node[node];
......@@ -1512,6 +1428,8 @@ void __init kmem_cache_init(void)
{
int i;
BUILD_BUG_ON(sizeof(((struct page *)NULL)->lru) <
sizeof(struct rcu_head));
kmem_cache = &kmem_cache_boot;
setup_node_pointer(kmem_cache);
......@@ -1687,7 +1605,7 @@ static noinline void
slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
{
struct kmem_cache_node *n;
struct slab *slabp;
struct page *page;
unsigned long flags;
int node;
......@@ -1706,15 +1624,15 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
continue;
spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(slabp, &n->slabs_full, list) {
list_for_each_entry(page, &n->slabs_full, lru) {
active_objs += cachep->num;
active_slabs++;
}
list_for_each_entry(slabp, &n->slabs_partial, list) {
active_objs += slabp->inuse;
list_for_each_entry(page, &n->slabs_partial, lru) {
active_objs += page->active;
active_slabs++;
}
list_for_each_entry(slabp, &n->slabs_free, list)
list_for_each_entry(page, &n->slabs_free, lru)
num_slabs++;
free_objects += n->free_objects;
......@@ -1736,19 +1654,11 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
* did not request dmaable memory, we might get it, but that
* would be relatively rare and ignorable.
*/
static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
int nodeid)
{
struct page *page;
int nr_pages;
int i;
#ifndef CONFIG_MMU
/*
* Nommu uses slab's for process anonymous memory allocations, and thus
* requires __GFP_COMP to properly refcount higher order allocations
*/
flags |= __GFP_COMP;
#endif
flags |= cachep->allocflags;
if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
......@@ -1772,12 +1682,9 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
else
add_zone_page_state(page_zone(page),
NR_SLAB_UNRECLAIMABLE, nr_pages);
for (i = 0; i < nr_pages; i++) {
__SetPageSlab(page + i);
__SetPageSlab(page);
if (page->pfmemalloc)
SetPageSlabPfmemalloc(page + i);
}
SetPageSlabPfmemalloc(page);
memcg_bind_pages(cachep, cachep->gfporder);
if (kmemcheck_enabled && !(cachep->flags & SLAB_NOTRACK)) {
......@@ -1789,17 +1696,15 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
kmemcheck_mark_unallocated_pages(page, nr_pages);
}
return page_address(page);
return page;
}
/*
* Interface to system's page release.
*/
static void kmem_freepages(struct kmem_cache *cachep, void *addr)
static void kmem_freepages(struct kmem_cache *cachep, struct page *page)
{
unsigned long i = (1 << cachep->gfporder);
struct page *page = virt_to_page(addr);
const unsigned long nr_freed = i;
const unsigned long nr_freed = (1 << cachep->gfporder);
kmemcheck_free_shadow(page, cachep->gfporder);
......@@ -1809,27 +1714,28 @@ static void kmem_freepages(struct kmem_cache *cachep, void *addr)
else
sub_zone_page_state(page_zone(page),
NR_SLAB_UNRECLAIMABLE, nr_freed);
while (i--) {
BUG_ON(!PageSlab(page));
__ClearPageSlabPfmemalloc(page);
__ClearPageSlab(page);
page++;
}
page_mapcount_reset(page);
page->mapping = NULL;
memcg_release_pages(cachep, cachep->gfporder);
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += nr_freed;
free_memcg_kmem_pages((unsigned long)addr, cachep->gfporder);
__free_memcg_kmem_pages(page, cachep->gfporder);
}
static void kmem_rcu_free(struct rcu_head *head)
{
struct slab_rcu *slab_rcu = (struct slab_rcu *)head;
struct kmem_cache *cachep = slab_rcu->cachep;
struct kmem_cache *cachep;
struct page *page;
kmem_freepages(cachep, slab_rcu->addr);
if (OFF_SLAB(cachep))
kmem_cache_free(cachep->slabp_cache, slab_rcu);
page = container_of(head, struct page, rcu_head);
cachep = page->slab_cache;
kmem_freepages(cachep, page);
}
#if DEBUG
......@@ -1978,19 +1884,19 @@ static void check_poison_obj(struct kmem_cache *cachep, void *objp)
/* Print some data about the neighboring objects, if they
* exist:
*/
struct slab *slabp = virt_to_slab(objp);
struct page *page = virt_to_head_page(objp);
unsigned int objnr;
objnr = obj_to_index(cachep, slabp, objp);
objnr = obj_to_index(cachep, page, objp);
if (objnr) {
objp = index_to_obj(cachep, slabp, objnr - 1);
objp = index_to_obj(cachep, page, objnr - 1);
realobj = (char *)objp + obj_offset(cachep);
printk(KERN_ERR "Prev obj: start=%p, len=%d\n",
realobj, size);
print_objinfo(cachep, objp, 2);
}
if (objnr + 1 < cachep->num) {
objp = index_to_obj(cachep, slabp, objnr + 1);
objp = index_to_obj(cachep, page, objnr + 1);
realobj = (char *)objp + obj_offset(cachep);
printk(KERN_ERR "Next obj: start=%p, len=%d\n",
realobj, size);
......@@ -2001,11 +1907,12 @@ static void check_poison_obj(struct kmem_cache *cachep, void *objp)
#endif
#if DEBUG
static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slabp)
static void slab_destroy_debugcheck(struct kmem_cache *cachep,
struct page *page)
{
int i;
for (i = 0; i < cachep->num; i++) {
void *objp = index_to_obj(cachep, slabp, i);
void *objp = index_to_obj(cachep, page, i);
if (cachep->flags & SLAB_POISON) {
#ifdef CONFIG_DEBUG_PAGEALLOC
......@@ -2030,7 +1937,8 @@ static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slab
}
}
#else
static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slabp)
static void slab_destroy_debugcheck(struct kmem_cache *cachep,
struct page *page)
{
}
#endif
......@@ -2044,23 +1952,34 @@ static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slab
* Before calling the slab must have been unlinked from the cache. The
* cache-lock is not held/needed.
*/
static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp)
static void slab_destroy(struct kmem_cache *cachep, struct page *page)
{
void *addr = slabp->s_mem - slabp->colouroff;
void *freelist;
slab_destroy_debugcheck(cachep, slabp);
freelist = page->freelist;
slab_destroy_debugcheck(cachep, page);
if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) {
struct slab_rcu *slab_rcu;
struct rcu_head *head;
/*
* RCU free overloads the RCU head over the LRU.
* slab_page has been overloeaded over the LRU,
* however it is not used from now on so that
* we can use it safely.
*/
head = (void *)&page->rcu_head;
call_rcu(head, kmem_rcu_free);
slab_rcu = (struct slab_rcu *)slabp;
slab_rcu->cachep = cachep;
slab_rcu->addr = addr;
call_rcu(&slab_rcu->head, kmem_rcu_free);
} else {
kmem_freepages(cachep, addr);
if (OFF_SLAB(cachep))
kmem_cache_free(cachep->slabp_cache, slabp);
kmem_freepages(cachep, page);
}
/*
* From now on, we don't use freelist
* although actual page can be freed in rcu context
*/
if (OFF_SLAB(cachep))
kmem_cache_free(cachep->freelist_cache, freelist);
}
/**
......@@ -2097,8 +2016,8 @@ static size_t calculate_slab_order(struct kmem_cache *cachep,
* use off-slab slabs. Needed to avoid a possible
* looping condition in cache_grow().
*/
offslab_limit = size - sizeof(struct slab);
offslab_limit /= sizeof(kmem_bufctl_t);
offslab_limit = size;
offslab_limit /= sizeof(unsigned int);
if (num > offslab_limit)
break;
......@@ -2220,7 +2139,7 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
int
__kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
{
size_t left_over, slab_size, ralign;
size_t left_over, freelist_size, ralign;
gfp_t gfp;
int err;
size_t size = cachep->size;
......@@ -2339,22 +2258,21 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
if (!cachep->num)
return -E2BIG;
slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t)
+ sizeof(struct slab), cachep->align);
freelist_size =
ALIGN(cachep->num * sizeof(unsigned int), cachep->align);
/*
* If the slab has been placed off-slab, and we have enough space then
* move it on-slab. This is at the expense of any extra colouring.
*/
if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) {
if (flags & CFLGS_OFF_SLAB && left_over >= freelist_size) {
flags &= ~CFLGS_OFF_SLAB;
left_over -= slab_size;
left_over -= freelist_size;
}
if (flags & CFLGS_OFF_SLAB) {
/* really off slab. No need for manual alignment */
slab_size =
cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab);
freelist_size = cachep->num * sizeof(unsigned int);
#ifdef CONFIG_PAGE_POISONING
/* If we're going to use the generic kernel_map_pages()
......@@ -2371,16 +2289,16 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
if (cachep->colour_off < cachep->align)
cachep->colour_off = cachep->align;
cachep->colour = left_over / cachep->colour_off;
cachep->slab_size = slab_size;
cachep->freelist_size = freelist_size;
cachep->flags = flags;
cachep->allocflags = 0;
cachep->allocflags = __GFP_COMP;
if (CONFIG_ZONE_DMA_FLAG && (flags & SLAB_CACHE_DMA))
cachep->allocflags |= GFP_DMA;
cachep->size = size;
cachep->reciprocal_buffer_size = reciprocal_value(size);
if (flags & CFLGS_OFF_SLAB) {
cachep->slabp_cache = kmalloc_slab(slab_size, 0u);
cachep->freelist_cache = kmalloc_slab(freelist_size, 0u);
/*
* This is a possibility for one of the malloc_sizes caches.
* But since we go off slab only for object size greater than
......@@ -2388,7 +2306,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
* this should not happen at all.
* But leave a BUG_ON for some lucky dude.
*/
BUG_ON(ZERO_OR_NULL_PTR(cachep->slabp_cache));
BUG_ON(ZERO_OR_NULL_PTR(cachep->freelist_cache));
}
err = setup_cpu_cache(cachep, gfp);
......@@ -2494,7 +2412,7 @@ static int drain_freelist(struct kmem_cache *cache,
{
struct list_head *p;
int nr_freed;
struct slab *slabp;
struct page *page;
nr_freed = 0;
while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
......@@ -2506,18 +2424,18 @@ static int drain_freelist(struct kmem_cache *cache,
goto out;
}
slabp = list_entry(p, struct slab, list);
page = list_entry(p, struct page, lru);
#if DEBUG
BUG_ON(slabp->inuse);
BUG_ON(page->active);
#endif
list_del(&slabp->list);
list_del(&page->lru);
/*
* Safe to drop the lock. The slab is no longer linked
* to the cache.
*/
n->free_objects -= cache->num;
spin_unlock_irq(&n->list_lock);
slab_destroy(cache, slabp);
slab_destroy(cache, page);
nr_freed++;
}
out:
......@@ -2600,52 +2518,42 @@ int __kmem_cache_shutdown(struct kmem_cache *cachep)
* descriptors in kmem_cache_create, we search through the malloc_sizes array.
* If we are creating a malloc_sizes cache here it would not be visible to
* kmem_find_general_cachep till the initialization is complete.
* Hence we cannot have slabp_cache same as the original cache.
* Hence we cannot have freelist_cache same as the original cache.
*/
static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp,
int colour_off, gfp_t local_flags,
int nodeid)
static void *alloc_slabmgmt(struct kmem_cache *cachep,
struct page *page, int colour_off,
gfp_t local_flags, int nodeid)
{
struct slab *slabp;
void *freelist;
void *addr = page_address(page);
if (OFF_SLAB(cachep)) {
/* Slab management obj is off-slab. */
slabp = kmem_cache_alloc_node(cachep->slabp_cache,
freelist = kmem_cache_alloc_node(cachep->freelist_cache,
local_flags, nodeid);
/*
* If the first object in the slab is leaked (it's allocated
* but no one has a reference to it), we want to make sure
* kmemleak does not treat the ->s_mem pointer as a reference
* to the object. Otherwise we will not report the leak.
*/
kmemleak_scan_area(&slabp->list, sizeof(struct list_head),
local_flags);
if (!slabp)
if (!freelist)
return NULL;
} else {
slabp = objp + colour_off;
colour_off += cachep->slab_size;
freelist = addr + colour_off;
colour_off += cachep->freelist_size;
}
slabp->inuse = 0;
slabp->colouroff = colour_off;
slabp->s_mem = objp + colour_off;
slabp->nodeid = nodeid;
slabp->free = 0;
return slabp;
page->active = 0;
page->s_mem = addr + colour_off;
return freelist;
}
static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp)
static inline unsigned int *slab_freelist(struct page *page)
{
return (kmem_bufctl_t *) (slabp + 1);
return (unsigned int *)(page->freelist);
}
static void cache_init_objs(struct kmem_cache *cachep,
struct slab *slabp)
struct page *page)
{
int i;
for (i = 0; i < cachep->num; i++) {
void *objp = index_to_obj(cachep, slabp, i);
void *objp = index_to_obj(cachep, page, i);
#if DEBUG
/* need to poison the objs? */
if (cachep->flags & SLAB_POISON)
......@@ -2681,9 +2589,8 @@ static void cache_init_objs(struct kmem_cache *cachep,
if (cachep->ctor)
cachep->ctor(objp);
#endif
slab_bufctl(slabp)[i] = i + 1;
slab_freelist(page)[i] = i;
}
slab_bufctl(slabp)[i - 1] = BUFCTL_END;
}
static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags)
......@@ -2696,41 +2603,41 @@ static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags)
}
}
static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp,
static void *slab_get_obj(struct kmem_cache *cachep, struct page *page,
int nodeid)
{
void *objp = index_to_obj(cachep, slabp, slabp->free);
kmem_bufctl_t next;
void *objp;
slabp->inuse++;
next = slab_bufctl(slabp)[slabp->free];
objp = index_to_obj(cachep, page, slab_freelist(page)[page->active]);
page->active++;
#if DEBUG
slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE;
WARN_ON(slabp->nodeid != nodeid);
WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);
#endif
slabp->free = next;
return objp;
}
static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp,
static void slab_put_obj(struct kmem_cache *cachep, struct page *page,
void *objp, int nodeid)
{
unsigned int objnr = obj_to_index(cachep, slabp, objp);
unsigned int objnr = obj_to_index(cachep, page, objp);
#if DEBUG
unsigned int i;
/* Verify that the slab belongs to the intended node */
WARN_ON(slabp->nodeid != nodeid);
WARN_ON(page_to_nid(virt_to_page(objp)) != nodeid);
if (slab_bufctl(slabp)[objnr] + 1 <= SLAB_LIMIT + 1) {
/* Verify double free bug */
for (i = page->active; i < cachep->num; i++) {
if (slab_freelist(page)[i] == objnr) {
printk(KERN_ERR "slab: double free detected in cache "
"'%s', objp %p\n", cachep->name, objp);
BUG();
}
}
#endif
slab_bufctl(slabp)[objnr] = slabp->free;
slabp->free = objnr;
slabp->inuse--;
page->active--;
slab_freelist(page)[page->active] = objnr;
}
/*
......@@ -2738,23 +2645,11 @@ static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp,
* for the slab allocator to be able to lookup the cache and slab of a
* virtual address for kfree, ksize, and slab debugging.
*/
static void slab_map_pages(struct kmem_cache *cache, struct slab *slab,
void *addr)
static void slab_map_pages(struct kmem_cache *cache, struct page *page,
void *freelist)
{
int nr_pages;
struct page *page;
page = virt_to_page(addr);
nr_pages = 1;
if (likely(!PageCompound(page)))
nr_pages <<= cache->gfporder;
do {
page->slab_cache = cache;
page->slab_page = slab;
page++;
} while (--nr_pages);
page->freelist = freelist;
}
/*
......@@ -2762,9 +2657,9 @@ static void slab_map_pages(struct kmem_cache *cache, struct slab *slab,
* kmem_cache_alloc() when there are no active objs left in a cache.
*/
static int cache_grow(struct kmem_cache *cachep,
gfp_t flags, int nodeid, void *objp)
gfp_t flags, int nodeid, struct page *page)
{
struct slab *slabp;
void *freelist;
size_t offset;
gfp_t local_flags;
struct kmem_cache_node *n;
......@@ -2805,20 +2700,20 @@ static int cache_grow(struct kmem_cache *cachep,
* Get mem for the objs. Attempt to allocate a physical page from
* 'nodeid'.
*/
if (!objp)
objp = kmem_getpages(cachep, local_flags, nodeid);
if (!objp)
if (!page)
page = kmem_getpages(cachep, local_flags, nodeid);
if (!page)
goto failed;
/* Get slab management. */
slabp = alloc_slabmgmt(cachep, objp, offset,
freelist = alloc_slabmgmt(cachep, page, offset,
local_flags & ~GFP_CONSTRAINT_MASK, nodeid);
if (!slabp)
if (!freelist)
goto opps1;
slab_map_pages(cachep, slabp, objp);
slab_map_pages(cachep, page, freelist);
cache_init_objs(cachep, slabp);
cache_init_objs(cachep, page);
if (local_flags & __GFP_WAIT)
local_irq_disable();
......@@ -2826,13 +2721,13 @@ static int cache_grow(struct kmem_cache *cachep,
spin_lock(&n->list_lock);
/* Make slab active. */
list_add_tail(&slabp->list, &(n->slabs_free));
list_add_tail(&page->lru, &(n->slabs_free));
STATS_INC_GROWN(cachep);
n->free_objects += cachep->num;
spin_unlock(&n->list_lock);
return 1;
opps1:
kmem_freepages(cachep, objp);
kmem_freepages(cachep, page);
failed:
if (local_flags & __GFP_WAIT)
local_irq_disable();
......@@ -2880,9 +2775,8 @@ static inline void verify_redzone_free(struct kmem_cache *cache, void *obj)
static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
unsigned long caller)
{
struct page *page;
unsigned int objnr;
struct slab *slabp;
struct page *page;
BUG_ON(virt_to_cache(objp) != cachep);
......@@ -2890,8 +2784,6 @@ static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
kfree_debugcheck(objp);
page = virt_to_head_page(objp);
slabp = page->slab_page;
if (cachep->flags & SLAB_RED_ZONE) {
verify_redzone_free(cachep, objp);
*dbg_redzone1(cachep, objp) = RED_INACTIVE;
......@@ -2900,14 +2792,11 @@ static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
if (cachep->flags & SLAB_STORE_USER)
*dbg_userword(cachep, objp) = (void *)caller;
objnr = obj_to_index(cachep, slabp, objp);
objnr = obj_to_index(cachep, page, objp);
BUG_ON(objnr >= cachep->num);
BUG_ON(objp != index_to_obj(cachep, slabp, objnr));
BUG_ON(objp != index_to_obj(cachep, page, objnr));
#ifdef CONFIG_DEBUG_SLAB_LEAK
slab_bufctl(slabp)[objnr] = BUFCTL_FREE;
#endif
if (cachep->flags & SLAB_POISON) {
#ifdef CONFIG_DEBUG_PAGEALLOC
if ((cachep->size % PAGE_SIZE)==0 && OFF_SLAB(cachep)) {
......@@ -2924,33 +2813,9 @@ static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
return objp;
}
static void check_slabp(struct kmem_cache *cachep, struct slab *slabp)
{
kmem_bufctl_t i;
int entries = 0;
/* Check slab's freelist to see if this obj is there. */
for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) {
entries++;
if (entries > cachep->num || i >= cachep->num)
goto bad;
}
if (entries != cachep->num - slabp->inuse) {
bad:
printk(KERN_ERR "slab: Internal list corruption detected in "
"cache '%s'(%d), slabp %p(%d). Tainted(%s). Hexdump:\n",
cachep->name, cachep->num, slabp, slabp->inuse,
print_tainted());
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, slabp,
sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t),
1);
BUG();
}
}
#else
#define kfree_debugcheck(x) do { } while(0)
#define cache_free_debugcheck(x,objp,z) (objp)
#define check_slabp(x,y) do { } while(0)
#endif
static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags,
......@@ -2989,7 +2854,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags,
while (batchcount > 0) {
struct list_head *entry;
struct slab *slabp;
struct page *page;
/* Get slab alloc is to come from. */
entry = n->slabs_partial.next;
if (entry == &n->slabs_partial) {
......@@ -2999,8 +2864,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags,
goto must_grow;
}
slabp = list_entry(entry, struct slab, list);
check_slabp(cachep, slabp);
page = list_entry(entry, struct page, lru);
check_spinlock_acquired(cachep);
/*
......@@ -3008,24 +2872,23 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags,
* there must be at least one object available for
* allocation.
*/
BUG_ON(slabp->inuse >= cachep->num);
BUG_ON(page->active >= cachep->num);
while (slabp->inuse < cachep->num && batchcount--) {
while (page->active < cachep->num && batchcount--) {
STATS_INC_ALLOCED(cachep);
STATS_INC_ACTIVE(cachep);
STATS_SET_HIGH(cachep);
ac_put_obj(cachep, ac, slab_get_obj(cachep, slabp,
ac_put_obj(cachep, ac, slab_get_obj(cachep, page,
node));
}
check_slabp(cachep, slabp);
/* move slabp to correct slabp list: */
list_del(&slabp->list);
if (slabp->free == BUFCTL_END)
list_add(&slabp->list, &n->slabs_full);
list_del(&page->lru);
if (page->active == cachep->num)
list_add(&page->list, &n->slabs_full);
else
list_add(&slabp->list, &n->slabs_partial);
list_add(&page->list, &n->slabs_partial);
}
must_grow:
......@@ -3097,16 +2960,6 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
*dbg_redzone1(cachep, objp) = RED_ACTIVE;
*dbg_redzone2(cachep, objp) = RED_ACTIVE;
}
#ifdef CONFIG_DEBUG_SLAB_LEAK
{
struct slab *slabp;
unsigned objnr;
slabp = virt_to_head_page(objp)->slab_page;
objnr = (unsigned)(objp - slabp->s_mem) / cachep->size;
slab_bufctl(slabp)[objnr] = BUFCTL_ACTIVE;
}
#endif
objp += obj_offset(cachep);
if (cachep->ctor && cachep->flags & SLAB_POISON)
cachep->ctor(objp);
......@@ -3248,18 +3101,20 @@ static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
* We may trigger various forms of reclaim on the allowed
* set and go into memory reserves if necessary.
*/
struct page *page;
if (local_flags & __GFP_WAIT)
local_irq_enable();
kmem_flagcheck(cache, flags);
obj = kmem_getpages(cache, local_flags, numa_mem_id());
page = kmem_getpages(cache, local_flags, numa_mem_id());
if (local_flags & __GFP_WAIT)
local_irq_disable();
if (obj) {
if (page) {
/*
* Insert into the appropriate per node queues
*/
nid = page_to_nid(virt_to_page(obj));
if (cache_grow(cache, flags, nid, obj)) {
nid = page_to_nid(page);
if (cache_grow(cache, flags, nid, page)) {
obj = ____cache_alloc_node(cache,
flags | GFP_THISNODE, nid);
if (!obj)
......@@ -3288,7 +3143,7 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
int nodeid)
{
struct list_head *entry;
struct slab *slabp;
struct page *page;
struct kmem_cache_node *n;
void *obj;
int x;
......@@ -3308,26 +3163,24 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
goto must_grow;
}
slabp = list_entry(entry, struct slab, list);
page = list_entry(entry, struct page, lru);
check_spinlock_acquired_node(cachep, nodeid);
check_slabp(cachep, slabp);
STATS_INC_NODEALLOCS(cachep);
STATS_INC_ACTIVE(cachep);
STATS_SET_HIGH(cachep);
BUG_ON(slabp->inuse == cachep->num);
BUG_ON(page->active == cachep->num);
obj = slab_get_obj(cachep, slabp, nodeid);
check_slabp(cachep, slabp);
obj = slab_get_obj(cachep, page, nodeid);
n->free_objects--;
/* move slabp to correct slabp list: */
list_del(&slabp->list);
list_del(&page->lru);
if (slabp->free == BUFCTL_END)
list_add(&slabp->list, &n->slabs_full);
if (page->active == cachep->num)
list_add(&page->lru, &n->slabs_full);
else
list_add(&slabp->list, &n->slabs_partial);
list_add(&page->lru, &n->slabs_partial);
spin_unlock(&n->list_lock);
goto done;
......@@ -3477,23 +3330,21 @@ static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects,
for (i = 0; i < nr_objects; i++) {
void *objp;
struct slab *slabp;
struct page *page;
clear_obj_pfmemalloc(&objpp[i]);
objp = objpp[i];
slabp = virt_to_slab(objp);
page = virt_to_head_page(objp);
n = cachep->node[node];
list_del(&slabp->list);
list_del(&page->lru);
check_spinlock_acquired_node(cachep, node);
check_slabp(cachep, slabp);
slab_put_obj(cachep, slabp, objp, node);
slab_put_obj(cachep, page, objp, node);
STATS_DEC_ACTIVE(cachep);
n->free_objects++;
check_slabp(cachep, slabp);
/* fixup slab chains */
if (slabp->inuse == 0) {
if (page->active == 0) {
if (n->free_objects > n->free_limit) {
n->free_objects -= cachep->num;
/* No need to drop any previously held
......@@ -3502,16 +3353,16 @@ static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects,
* a different cache, refer to comments before
* alloc_slabmgmt.
*/
slab_destroy(cachep, slabp);
slab_destroy(cachep, page);
} else {
list_add(&slabp->list, &n->slabs_free);
list_add(&page->lru, &n->slabs_free);
}
} else {
/* Unconditionally move a slab to the end of the
* partial list on free - maximum time for the
* other objects to be freed, too.
*/
list_add_tail(&slabp->list, &n->slabs_partial);
list_add_tail(&page->lru, &n->slabs_partial);
}
}
}
......@@ -3551,10 +3402,10 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
p = n->slabs_free.next;
while (p != &(n->slabs_free)) {
struct slab *slabp;
struct page *page;
slabp = list_entry(p, struct slab, list);
BUG_ON(slabp->inuse);
page = list_entry(p, struct page, lru);
BUG_ON(page->active);
i++;
p = p->next;
......@@ -4158,7 +4009,7 @@ static void cache_reap(struct work_struct *w)
#ifdef CONFIG_SLABINFO
void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
{
struct slab *slabp;
struct page *page;
unsigned long active_objs;
unsigned long num_objs;
unsigned long active_slabs = 0;
......@@ -4178,23 +4029,23 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
check_irq_on();
spin_lock_irq(&n->list_lock);
list_for_each_entry(slabp, &n->slabs_full, list) {
if (slabp->inuse != cachep->num && !error)
list_for_each_entry(page, &n->slabs_full, lru) {
if (page->active != cachep->num && !error)
error = "slabs_full accounting error";
active_objs += cachep->num;
active_slabs++;
}
list_for_each_entry(slabp, &n->slabs_partial, list) {
if (slabp->inuse == cachep->num && !error)
error = "slabs_partial inuse accounting error";
if (!slabp->inuse && !error)
error = "slabs_partial/inuse accounting error";
active_objs += slabp->inuse;
list_for_each_entry(page, &n->slabs_partial, lru) {
if (page->active == cachep->num && !error)
error = "slabs_partial accounting error";
if (!page->active && !error)
error = "slabs_partial accounting error";
active_objs += page->active;
active_slabs++;
}
list_for_each_entry(slabp, &n->slabs_free, list) {
if (slabp->inuse && !error)
error = "slabs_free/inuse accounting error";
list_for_each_entry(page, &n->slabs_free, lru) {
if (page->active && !error)
error = "slabs_free accounting error";
num_slabs++;
}
free_objects += n->free_objects;
......@@ -4346,15 +4197,27 @@ static inline int add_caller(unsigned long *n, unsigned long v)
return 1;
}
static void handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s)
static void handle_slab(unsigned long *n, struct kmem_cache *c,
struct page *page)
{
void *p;
int i;
int i, j;
if (n[0] == n[1])
return;
for (i = 0, p = s->s_mem; i < c->num; i++, p += c->size) {
if (slab_bufctl(s)[i] != BUFCTL_ACTIVE)
for (i = 0, p = page->s_mem; i < c->num; i++, p += c->size) {
bool active = true;
for (j = page->active; j < c->num; j++) {
/* Skip freed item */
if (slab_freelist(page)[j] == i) {
active = false;
break;
}
}
if (!active)
continue;
if (!add_caller(n, (unsigned long)*dbg_userword(c, p)))
return;
}
......@@ -4379,7 +4242,7 @@ static void show_symbol(struct seq_file *m, unsigned long address)
static int leaks_show(struct seq_file *m, void *p)
{
struct kmem_cache *cachep = list_entry(p, struct kmem_cache, list);
struct slab *slabp;
struct page *page;
struct kmem_cache_node *n;
const char *name;
unsigned long *x = m->private;
......@@ -4403,10 +4266,10 @@ static int leaks_show(struct seq_file *m, void *p)
check_irq_on();
spin_lock_irq(&n->list_lock);
list_for_each_entry(slabp, &n->slabs_full, list)
handle_slab(x, cachep, slabp);
list_for_each_entry(slabp, &n->slabs_partial, list)
handle_slab(x, cachep, slabp);
list_for_each_entry(page, &n->slabs_full, lru)
handle_slab(x, cachep, page);
list_for_each_entry(page, &n->slabs_partial, lru)
handle_slab(x, cachep, page);
spin_unlock_irq(&n->list_lock);
}
name = cachep->name;
......
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