| /* |
| * linux/mm/slab.c |
| * Written by Mark Hemment, 1996/97. |
| * (markhe@nextd.demon.co.uk) |
| * |
| * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli |
| * |
| * Major cleanup, different bufctl logic, per-cpu arrays |
| * (c) 2000 Manfred Spraul |
| * |
| * Cleanup, make the head arrays unconditional, preparation for NUMA |
| * (c) 2002 Manfred Spraul |
| * |
| * An implementation of the Slab Allocator as described in outline in; |
| * UNIX Internals: The New Frontiers by Uresh Vahalia |
| * Pub: Prentice Hall ISBN 0-13-101908-2 |
| * or with a little more detail in; |
| * The Slab Allocator: An Object-Caching Kernel Memory Allocator |
| * Jeff Bonwick (Sun Microsystems). |
| * Presented at: USENIX Summer 1994 Technical Conference |
| * |
| * The memory is organized in caches, one cache for each object type. |
| * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) |
| * Each cache consists out of many slabs (they are small (usually one |
| * page long) and always contiguous), and each slab contains multiple |
| * initialized objects. |
| * |
| * This means, that your constructor is used only for newly allocated |
| * slabs and you must pass objects with the same intializations to |
| * kmem_cache_free. |
| * |
| * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, |
| * normal). If you need a special memory type, then must create a new |
| * cache for that memory type. |
| * |
| * In order to reduce fragmentation, the slabs are sorted in 3 groups: |
| * full slabs with 0 free objects |
| * partial slabs |
| * empty slabs with no allocated objects |
| * |
| * If partial slabs exist, then new allocations come from these slabs, |
| * otherwise from empty slabs or new slabs are allocated. |
| * |
| * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache |
| * during kmem_cache_destroy(). The caller must prevent concurrent allocs. |
| * |
| * Each cache has a short per-cpu head array, most allocs |
| * and frees go into that array, and if that array overflows, then 1/2 |
| * of the entries in the array are given back into the global cache. |
| * The head array is strictly LIFO and should improve the cache hit rates. |
| * On SMP, it additionally reduces the spinlock operations. |
| * |
| * The c_cpuarray may not be read with enabled local interrupts - |
| * it's changed with a smp_call_function(). |
| * |
| * SMP synchronization: |
| * constructors and destructors are called without any locking. |
| * Several members in struct kmem_cache and struct slab never change, they |
| * are accessed without any locking. |
| * The per-cpu arrays are never accessed from the wrong cpu, no locking, |
| * and local interrupts are disabled so slab code is preempt-safe. |
| * The non-constant members are protected with a per-cache irq spinlock. |
| * |
| * Many thanks to Mark Hemment, who wrote another per-cpu slab patch |
| * in 2000 - many ideas in the current implementation are derived from |
| * his patch. |
| * |
| * Further notes from the original documentation: |
| * |
| * 11 April '97. Started multi-threading - markhe |
| * The global cache-chain is protected by the mutex 'cache_chain_mutex'. |
| * The sem is only needed when accessing/extending the cache-chain, which |
| * can never happen inside an interrupt (kmem_cache_create(), |
| * kmem_cache_shrink() and kmem_cache_reap()). |
| * |
| * At present, each engine can be growing a cache. This should be blocked. |
| * |
| * 15 March 2005. NUMA slab allocator. |
| * Shai Fultheim <shai@scalex86.org>. |
| * Shobhit Dayal <shobhit@calsoftinc.com> |
| * Alok N Kataria <alokk@calsoftinc.com> |
| * Christoph Lameter <christoph@lameter.com> |
| * |
| * Modified the slab allocator to be node aware on NUMA systems. |
| * Each node has its own list of partial, free and full slabs. |
| * All object allocations for a node occur from node specific slab lists. |
| */ |
| |
| #include <linux/slab.h> |
| #include <linux/mm.h> |
| #include <linux/poison.h> |
| #include <linux/swap.h> |
| #include <linux/cache.h> |
| #include <linux/interrupt.h> |
| #include <linux/init.h> |
| #include <linux/compiler.h> |
| #include <linux/cpuset.h> |
| #include <linux/seq_file.h> |
| #include <linux/notifier.h> |
| #include <linux/kallsyms.h> |
| #include <linux/cpu.h> |
| #include <linux/sysctl.h> |
| #include <linux/module.h> |
| #include <linux/rcupdate.h> |
| #include <linux/string.h> |
| #include <linux/uaccess.h> |
| #include <linux/nodemask.h> |
| #include <linux/mempolicy.h> |
| #include <linux/mutex.h> |
| #include <linux/fault-inject.h> |
| #include <linux/rtmutex.h> |
| #include <linux/reciprocal_div.h> |
| |
| #include <asm/cacheflush.h> |
| #include <asm/tlbflush.h> |
| #include <asm/page.h> |
| |
| /* |
| * DEBUG - 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON. |
| * 0 for faster, smaller code (especially in the critical paths). |
| * |
| * STATS - 1 to collect stats for /proc/slabinfo. |
| * 0 for faster, smaller code (especially in the critical paths). |
| * |
| * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) |
| */ |
| |
| #ifdef CONFIG_DEBUG_SLAB |
| #define DEBUG 1 |
| #define STATS 1 |
| #define FORCED_DEBUG 1 |
| #else |
| #define DEBUG 0 |
| #define STATS 0 |
| #define FORCED_DEBUG 0 |
| #endif |
| |
| /* Shouldn't this be in a header file somewhere? */ |
| #define BYTES_PER_WORD sizeof(void *) |
| #define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long)) |
| |
| #ifndef cache_line_size |
| #define cache_line_size() L1_CACHE_BYTES |
| #endif |
| |
| #ifndef ARCH_KMALLOC_MINALIGN |
| /* |
| * 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. |
| */ |
| #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 |
| |
| #ifndef ARCH_KMALLOC_FLAGS |
| #define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN |
| #endif |
| |
| /* Legal flag mask for kmem_cache_create(). */ |
| #if DEBUG |
| # define CREATE_MASK (SLAB_RED_ZONE | \ |
| SLAB_POISON | SLAB_HWCACHE_ALIGN | \ |
| SLAB_CACHE_DMA | \ |
| SLAB_STORE_USER | \ |
| SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ |
| SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD) |
| #else |
| # define CREATE_MASK (SLAB_HWCACHE_ALIGN | \ |
| SLAB_CACHE_DMA | \ |
| SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ |
| SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD) |
| #endif |
| |
| /* |
| * 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 |
| * |
| * 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 |
| * 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. |
| * |
| * We assume struct slab_rcu can overlay struct slab when destroying. |
| */ |
| struct slab_rcu { |
| struct rcu_head head; |
| struct kmem_cache *cachep; |
| void *addr; |
| }; |
| |
| /* |
| * struct array_cache |
| * |
| * Purpose: |
| * - LIFO ordering, to hand out cache-warm objects from _alloc |
| * - reduce the number of linked list operations |
| * - reduce spinlock operations |
| * |
| * The limit is stored in the per-cpu structure to reduce the data cache |
| * footprint. |
| * |
| */ |
| struct array_cache { |
| unsigned int avail; |
| unsigned int limit; |
| unsigned int batchcount; |
| unsigned int touched; |
| spinlock_t lock; |
| void *entry[0]; /* |
| * Must have this definition in here for the proper |
| * alignment of array_cache. Also simplifies accessing |
| * the entries. |
| * [0] is for gcc 2.95. It should really be []. |
| */ |
| }; |
| |
| /* |
| * bootstrap: The caches do not work without cpuarrays anymore, but the |
| * cpuarrays are allocated from the generic caches... |
| */ |
| #define BOOT_CPUCACHE_ENTRIES 1 |
| struct arraycache_init { |
| struct array_cache cache; |
| void *entries[BOOT_CPUCACHE_ENTRIES]; |
| }; |
| |
| /* |
| * The slab lists for all objects. |
| */ |
| struct kmem_list3 { |
| struct list_head slabs_partial; /* partial list first, better asm code */ |
| struct list_head slabs_full; |
| struct list_head slabs_free; |
| unsigned long free_objects; |
| unsigned int free_limit; |
| unsigned int colour_next; /* Per-node cache coloring */ |
| spinlock_t list_lock; |
| struct array_cache *shared; /* shared per node */ |
| struct array_cache **alien; /* on other nodes */ |
| unsigned long next_reap; /* updated without locking */ |
| int free_touched; /* updated without locking */ |
| }; |
| |
| /* |
| * Need this for bootstrapping a per node allocator. |
| */ |
| #define NUM_INIT_LISTS (2 * MAX_NUMNODES + 1) |
| struct kmem_list3 __initdata initkmem_list3[NUM_INIT_LISTS]; |
| #define CACHE_CACHE 0 |
| #define SIZE_AC 1 |
| #define SIZE_L3 (1 + MAX_NUMNODES) |
| |
| static int drain_freelist(struct kmem_cache *cache, |
| struct kmem_list3 *l3, int tofree); |
| static void free_block(struct kmem_cache *cachep, void **objpp, int len, |
| int node); |
| static int enable_cpucache(struct kmem_cache *cachep); |
| static void cache_reap(struct work_struct *unused); |
| |
| /* |
| * This function must be completely optimized away if a constant is passed to |
| * it. Mostly the same as what is in linux/slab.h except it returns an index. |
| */ |
| static __always_inline int index_of(const size_t size) |
| { |
| extern void __bad_size(void); |
| |
| if (__builtin_constant_p(size)) { |
| int i = 0; |
| |
| #define CACHE(x) \ |
| if (size <=x) \ |
| return i; \ |
| else \ |
| i++; |
| #include "linux/kmalloc_sizes.h" |
| #undef CACHE |
| __bad_size(); |
| } else |
| __bad_size(); |
| return 0; |
| } |
| |
| static int slab_early_init = 1; |
| |
| #define INDEX_AC index_of(sizeof(struct arraycache_init)) |
| #define INDEX_L3 index_of(sizeof(struct kmem_list3)) |
| |
| static void kmem_list3_init(struct kmem_list3 *parent) |
| { |
| INIT_LIST_HEAD(&parent->slabs_full); |
| INIT_LIST_HEAD(&parent->slabs_partial); |
| INIT_LIST_HEAD(&parent->slabs_free); |
| parent->shared = NULL; |
| parent->alien = NULL; |
| parent->colour_next = 0; |
| spin_lock_init(&parent->list_lock); |
| parent->free_objects = 0; |
| parent->free_touched = 0; |
| } |
| |
| #define MAKE_LIST(cachep, listp, slab, nodeid) \ |
| do { \ |
| INIT_LIST_HEAD(listp); \ |
| list_splice(&(cachep->nodelists[nodeid]->slab), listp); \ |
| } while (0) |
| |
| #define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ |
| do { \ |
| MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ |
| MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ |
| MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ |
| } while (0) |
| |
| /* |
| * struct kmem_cache |
| * |
| * manages a cache. |
| */ |
| |
| 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 */ |
| 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 */ |
| |
| unsigned int flags; /* constant flags */ |
| unsigned int num; /* # of objs per slab */ |
| |
| /* 4) cache_grow/shrink */ |
| /* order of pgs per slab (2^n) */ |
| unsigned int gfporder; |
| |
| /* force GFP flags, e.g. GFP_DMA */ |
| gfp_t gfpflags; |
| |
| size_t colour; /* cache colouring range */ |
| unsigned int colour_off; /* colour offset */ |
| struct kmem_cache *slabp_cache; |
| unsigned int slab_size; |
| unsigned int dflags; /* dynamic flags */ |
| |
| /* constructor func */ |
| void (*ctor) (void *, struct kmem_cache *, unsigned long); |
| |
| /* 5) cache creation/removal */ |
| const char *name; |
| struct list_head next; |
| |
| /* 6) statistics */ |
| #if STATS |
| unsigned long num_active; |
| unsigned long num_allocations; |
| unsigned long high_mark; |
| unsigned long grown; |
| unsigned long reaped; |
| unsigned long errors; |
| unsigned long max_freeable; |
| unsigned long node_allocs; |
| unsigned long node_frees; |
| unsigned long node_overflow; |
| atomic_t allochit; |
| atomic_t allocmiss; |
| atomic_t freehit; |
| atomic_t freemiss; |
| #endif |
| #if DEBUG |
| /* |
| * If debugging is enabled, then the allocator can add additional |
| * fields and/or padding to every object. buffer_size contains the total |
| * object size including these internal fields, the following two |
| * variables contain the offset to the user object and its size. |
| */ |
| int obj_offset; |
| int obj_size; |
| #endif |
| /* |
| * 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 |
| * (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. |
| */ |
| struct kmem_list3 *nodelists[MAX_NUMNODES]; |
| /* |
| * Do not add fields after nodelists[] |
| */ |
| }; |
| |
| #define CFLGS_OFF_SLAB (0x80000000UL) |
| #define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) |
| |
| #define BATCHREFILL_LIMIT 16 |
| /* |
| * Optimization question: fewer reaps means less probability for unnessary |
| * cpucache drain/refill cycles. |
| * |
| * OTOH the cpuarrays can contain lots of objects, |
| * which could lock up otherwise freeable slabs. |
| */ |
| #define REAPTIMEOUT_CPUC (2*HZ) |
| #define REAPTIMEOUT_LIST3 (4*HZ) |
| |
| #if STATS |
| #define STATS_INC_ACTIVE(x) ((x)->num_active++) |
| #define STATS_DEC_ACTIVE(x) ((x)->num_active--) |
| #define STATS_INC_ALLOCED(x) ((x)->num_allocations++) |
| #define STATS_INC_GROWN(x) ((x)->grown++) |
| #define STATS_ADD_REAPED(x,y) ((x)->reaped += (y)) |
| #define STATS_SET_HIGH(x) \ |
| do { \ |
| if ((x)->num_active > (x)->high_mark) \ |
| (x)->high_mark = (x)->num_active; \ |
| } while (0) |
| #define STATS_INC_ERR(x) ((x)->errors++) |
| #define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) |
| #define STATS_INC_NODEFREES(x) ((x)->node_frees++) |
| #define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) |
| #define STATS_SET_FREEABLE(x, i) \ |
| do { \ |
| if ((x)->max_freeable < i) \ |
| (x)->max_freeable = i; \ |
| } while (0) |
| #define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) |
| #define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) |
| #define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) |
| #define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) |
| #else |
| #define STATS_INC_ACTIVE(x) do { } while (0) |
| #define STATS_DEC_ACTIVE(x) do { } while (0) |
| #define STATS_INC_ALLOCED(x) do { } while (0) |
| #define STATS_INC_GROWN(x) do { } while (0) |
| #define STATS_ADD_REAPED(x,y) do { } while (0) |
| #define STATS_SET_HIGH(x) do { } while (0) |
| #define STATS_INC_ERR(x) do { } while (0) |
| #define STATS_INC_NODEALLOCS(x) do { } while (0) |
| #define STATS_INC_NODEFREES(x) do { } while (0) |
| #define STATS_INC_ACOVERFLOW(x) do { } while (0) |
| #define STATS_SET_FREEABLE(x, i) do { } while (0) |
| #define STATS_INC_ALLOCHIT(x) do { } while (0) |
| #define STATS_INC_ALLOCMISS(x) do { } while (0) |
| #define STATS_INC_FREEHIT(x) do { } while (0) |
| #define STATS_INC_FREEMISS(x) do { } while (0) |
| #endif |
| |
| #if DEBUG |
| |
| /* |
| * memory layout of objects: |
| * 0 : objp |
| * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that |
| * the end of an object is aligned with the end of the real |
| * allocation. Catches writes behind the end of the allocation. |
| * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: |
| * redzone word. |
| * cachep->obj_offset: The real object. |
| * cachep->buffer_size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] |
| * cachep->buffer_size - 1* BYTES_PER_WORD: last caller address |
| * [BYTES_PER_WORD long] |
| */ |
| static int obj_offset(struct kmem_cache *cachep) |
| { |
| return cachep->obj_offset; |
| } |
| |
| static int obj_size(struct kmem_cache *cachep) |
| { |
| return cachep->obj_size; |
| } |
| |
| static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp) |
| { |
| BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); |
| return (unsigned long long*) (objp + obj_offset(cachep) - |
| sizeof(unsigned long long)); |
| } |
| |
| static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp) |
| { |
| BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); |
| if (cachep->flags & SLAB_STORE_USER) |
| return (unsigned long long *)(objp + cachep->buffer_size - |
| sizeof(unsigned long long) - |
| REDZONE_ALIGN); |
| return (unsigned long long *) (objp + cachep->buffer_size - |
| sizeof(unsigned long long)); |
| } |
| |
| static void **dbg_userword(struct kmem_cache *cachep, void *objp) |
| { |
| BUG_ON(!(cachep->flags & SLAB_STORE_USER)); |
| return (void **)(objp + cachep->buffer_size - BYTES_PER_WORD); |
| } |
| |
| #else |
| |
| #define obj_offset(x) 0 |
| #define obj_size(cachep) (cachep->buffer_size) |
| #define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) |
| #define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long long *)NULL;}) |
| #define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) |
| |
| #endif |
| |
| /* |
| * Do not go above this order unless 0 objects fit into the slab. |
| */ |
| #define BREAK_GFP_ORDER_HI 1 |
| #define BREAK_GFP_ORDER_LO 0 |
| static int slab_break_gfp_order = BREAK_GFP_ORDER_LO; |
| |
| /* |
| * Functions for storing/retrieving the cachep and or slab from the page |
| * allocator. These are used to find the slab an obj belongs to. With kfree(), |
| * these are used to find the cache which an obj belongs to. |
| */ |
| static inline void page_set_cache(struct page *page, struct kmem_cache *cache) |
| { |
| page->lru.next = (struct list_head *)cache; |
| } |
| |
| static inline struct kmem_cache *page_get_cache(struct page *page) |
| { |
| page = compound_head(page); |
| BUG_ON(!PageSlab(page)); |
| return (struct kmem_cache *)page->lru.next; |
| } |
| |
| static inline void page_set_slab(struct page *page, struct slab *slab) |
| { |
| page->lru.prev = (struct list_head *)slab; |
| } |
| |
| static inline struct slab *page_get_slab(struct page *page) |
| { |
| BUG_ON(!PageSlab(page)); |
| return (struct slab *)page->lru.prev; |
| } |
| |
| static inline struct kmem_cache *virt_to_cache(const void *obj) |
| { |
| struct page *page = virt_to_head_page(obj); |
| return page_get_cache(page); |
| } |
| |
| static inline struct slab *virt_to_slab(const void *obj) |
| { |
| struct page *page = virt_to_head_page(obj); |
| return page_get_slab(page); |
| } |
| |
| static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab, |
| unsigned int idx) |
| { |
| return slab->s_mem + cache->buffer_size * idx; |
| } |
| |
| /* |
| * We want to avoid an expensive divide : (offset / cache->buffer_size) |
| * Using the fact that buffer_size is a constant for a particular cache, |
| * we can replace (offset / cache->buffer_size) by |
| * 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) |
| { |
| u32 offset = (obj - slab->s_mem); |
| return reciprocal_divide(offset, cache->reciprocal_buffer_size); |
| } |
| |
| /* |
| * These are the default caches for kmalloc. Custom caches can have other sizes. |
| */ |
| struct cache_sizes malloc_sizes[] = { |
| #define CACHE(x) { .cs_size = (x) }, |
| #include <linux/kmalloc_sizes.h> |
| CACHE(ULONG_MAX) |
| #undef CACHE |
| }; |
| EXPORT_SYMBOL(malloc_sizes); |
| |
| /* Must match cache_sizes above. Out of line to keep cache footprint low. */ |
| struct cache_names { |
| char *name; |
| char *name_dma; |
| }; |
| |
| static struct cache_names __initdata cache_names[] = { |
| #define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" }, |
| #include <linux/kmalloc_sizes.h> |
| {NULL,} |
| #undef CACHE |
| }; |
| |
| static struct arraycache_init initarray_cache __initdata = |
| { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
| static struct arraycache_init initarray_generic = |
| { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
| |
| /* internal cache of cache description objs */ |
| static struct kmem_cache cache_cache = { |
| .batchcount = 1, |
| .limit = BOOT_CPUCACHE_ENTRIES, |
| .shared = 1, |
| .buffer_size = sizeof(struct kmem_cache), |
| .name = "kmem_cache", |
| }; |
| |
| #define BAD_ALIEN_MAGIC 0x01020304ul |
| |
| #ifdef CONFIG_LOCKDEP |
| |
| /* |
| * Slab sometimes uses the kmalloc slabs to store the slab headers |
| * for other slabs "off slab". |
| * The locking for this is tricky in that it nests within the locks |
| * of all other slabs in a few places; to deal with this special |
| * locking we put on-slab caches into a separate lock-class. |
| * |
| * We set lock class for alien array caches which are up during init. |
| * The lock annotation will be lost if all cpus of a node goes down and |
| * then comes back up during hotplug |
| */ |
| static struct lock_class_key on_slab_l3_key; |
| static struct lock_class_key on_slab_alc_key; |
| |
| static inline void init_lock_keys(void) |
| |
| { |
| int q; |
| struct cache_sizes *s = malloc_sizes; |
| |
| while (s->cs_size != ULONG_MAX) { |
| for_each_node(q) { |
| struct array_cache **alc; |
| int r; |
| struct kmem_list3 *l3 = s->cs_cachep->nodelists[q]; |
| if (!l3 || OFF_SLAB(s->cs_cachep)) |
| continue; |
| lockdep_set_class(&l3->list_lock, &on_slab_l3_key); |
| alc = l3->alien; |
| /* |
| * FIXME: This check for BAD_ALIEN_MAGIC |
| * should go away when common slab code is taught to |
| * work even without alien caches. |
| * Currently, non NUMA code returns BAD_ALIEN_MAGIC |
| * for alloc_alien_cache, |
| */ |
| if (!alc || (unsigned long)alc == BAD_ALIEN_MAGIC) |
| continue; |
| for_each_node(r) { |
| if (alc[r]) |
| lockdep_set_class(&alc[r]->lock, |
| &on_slab_alc_key); |
| } |
| } |
| s++; |
| } |
| } |
| #else |
| static inline void init_lock_keys(void) |
| { |
| } |
| #endif |
| |
| /* |
| * 1. Guard access to the cache-chain. |
| * 2. Protect sanity of cpu_online_map against cpu hotplug events |
| */ |
| static DEFINE_MUTEX(cache_chain_mutex); |
| static struct list_head cache_chain; |
| |
| /* |
| * chicken and egg problem: delay the per-cpu array allocation |
| * until the general caches are up. |
| */ |
| static enum { |
| NONE, |
| PARTIAL_AC, |
| PARTIAL_L3, |
| FULL |
| } g_cpucache_up; |
| |
| /* |
| * used by boot code to determine if it can use slab based allocator |
| */ |
| int slab_is_available(void) |
| { |
| return g_cpucache_up == FULL; |
| } |
| |
| static DEFINE_PER_CPU(struct delayed_work, reap_work); |
| |
| static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) |
| { |
| return cachep->array[smp_processor_id()]; |
| } |
| |
| static inline struct kmem_cache *__find_general_cachep(size_t size, |
| gfp_t gfpflags) |
| { |
| struct cache_sizes *csizep = malloc_sizes; |
| |
| #if DEBUG |
| /* This happens if someone tries to call |
| * kmem_cache_create(), or __kmalloc(), before |
| * the generic caches are initialized. |
| */ |
| BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL); |
| #endif |
| if (!size) |
| return ZERO_SIZE_PTR; |
| |
| while (size > csizep->cs_size) |
| csizep++; |
| |
| /* |
| * Really subtle: The last entry with cs->cs_size==ULONG_MAX |
| * has cs_{dma,}cachep==NULL. Thus no special case |
| * for large kmalloc calls required. |
| */ |
| #ifdef CONFIG_ZONE_DMA |
| if (unlikely(gfpflags & GFP_DMA)) |
| return csizep->cs_dmacachep; |
| #endif |
| return csizep->cs_cachep; |
| } |
| |
| static struct kmem_cache *kmem_find_general_cachep(size_t size, gfp_t gfpflags) |
| { |
| return __find_general_cachep(size, gfpflags); |
| } |
| |
| 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); |
| } |
| |
| /* |
| * Calculate the number of objects and left-over bytes for a given buffer size. |
| */ |
| static void cache_estimate(unsigned long gfporder, size_t buffer_size, |
| size_t align, int flags, size_t *left_over, |
| unsigned int *num) |
| { |
| int nr_objs; |
| size_t mgmt_size; |
| size_t slab_size = PAGE_SIZE << gfporder; |
| |
| /* |
| * The slab management structure can be either off the slab or |
| * 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 |
| * - Padding to respect alignment of @align |
| * - @buffer_size bytes for each object |
| * |
| * If the slab management structure is off the slab, then the |
| * alignment will already be calculated into the size. Because |
| * the slabs are all pages aligned, the objects will be at the |
| * correct alignment when allocated. |
| */ |
| if (flags & CFLGS_OFF_SLAB) { |
| 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 |
| * is at most @align-1 bytes, and @buffer_size is at |
| * least @align. In the worst case, this result will |
| * be one greater than the number of objects that fit |
| * into the memory allocation when taking the padding |
| * into account. |
| */ |
| nr_objs = (slab_size - sizeof(struct slab)) / |
| (buffer_size + sizeof(kmem_bufctl_t)); |
| |
| /* |
| * This calculated number will be either the right |
| * amount, or one greater than what we want. |
| */ |
| if (slab_mgmt_size(nr_objs, align) + nr_objs*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; |
| *left_over = slab_size - nr_objs*buffer_size - mgmt_size; |
| } |
| |
| #define slab_error(cachep, msg) __slab_error(__FUNCTION__, cachep, msg) |
| |
| static void __slab_error(const char *function, struct kmem_cache *cachep, |
| char *msg) |
| { |
| printk(KERN_ERR "slab error in %s(): cache `%s': %s\n", |
| function, cachep->name, msg); |
| dump_stack(); |
| } |
| |
| /* |
| * By default on NUMA we use alien caches to stage the freeing of |
| * objects allocated from other nodes. This causes massive memory |
| * inefficiencies when using fake NUMA setup to split memory into a |
| * large number of small nodes, so it can be disabled on the command |
| * line |
| */ |
| |
| static int use_alien_caches __read_mostly = 1; |
| static int __init noaliencache_setup(char *s) |
| { |
| use_alien_caches = 0; |
| return 1; |
| } |
| __setup("noaliencache", noaliencache_setup); |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * Special reaping functions for NUMA systems called from cache_reap(). |
| * These take care of doing round robin flushing of alien caches (containing |
| * objects freed on different nodes from which they were allocated) and the |
| * flushing of remote pcps by calling drain_node_pages. |
| */ |
| static DEFINE_PER_CPU(unsigned long, reap_node); |
| |
| static void init_reap_node(int cpu) |
| { |
| int node; |
| |
| node = next_node(cpu_to_node(cpu), node_online_map); |
| if (node == MAX_NUMNODES) |
| node = first_node(node_online_map); |
| |
| per_cpu(reap_node, cpu) = node; |
| } |
| |
| static void next_reap_node(void) |
| { |
| int node = __get_cpu_var(reap_node); |
| |
| node = next_node(node, node_online_map); |
| if (unlikely(node >= MAX_NUMNODES)) |
| node = first_node(node_online_map); |
| __get_cpu_var(reap_node) = node; |
| } |
| |
| #else |
| #define init_reap_node(cpu) do { } while (0) |
| #define next_reap_node(void) do { } while (0) |
| #endif |
| |
| /* |
| * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz |
| * via the workqueue/eventd. |
| * Add the CPU number into the expiration time to minimize the possibility of |
| * the CPUs getting into lockstep and contending for the global cache chain |
| * lock. |
| */ |
| static void __cpuinit start_cpu_timer(int cpu) |
| { |
| struct delayed_work *reap_work = &per_cpu(reap_work, cpu); |
| |
| /* |
| * When this gets called from do_initcalls via cpucache_init(), |
| * init_workqueues() has already run, so keventd will be setup |
| * at that time. |
| */ |
| if (keventd_up() && reap_work->work.func == NULL) { |
| init_reap_node(cpu); |
| INIT_DELAYED_WORK(reap_work, cache_reap); |
| schedule_delayed_work_on(cpu, reap_work, |
| __round_jiffies_relative(HZ, cpu)); |
| } |
| } |
| |
| static struct array_cache *alloc_arraycache(int node, int entries, |
| int batchcount) |
| { |
| int memsize = sizeof(void *) * entries + sizeof(struct array_cache); |
| struct array_cache *nc = NULL; |
| |
| nc = kmalloc_node(memsize, GFP_KERNEL, node); |
| if (nc) { |
| nc->avail = 0; |
| nc->limit = entries; |
| nc->batchcount = batchcount; |
| nc->touched = 0; |
| spin_lock_init(&nc->lock); |
| } |
| return nc; |
| } |
| |
| /* |
| * Transfer objects in one arraycache to another. |
| * Locking must be handled by the caller. |
| * |
| * Return the number of entries transferred. |
| */ |
| static int transfer_objects(struct array_cache *to, |
| struct array_cache *from, unsigned int max) |
| { |
| /* Figure out how many entries to transfer */ |
| int nr = min(min(from->avail, max), to->limit - to->avail); |
| |
| if (!nr) |
| return 0; |
| |
| memcpy(to->entry + to->avail, from->entry + from->avail -nr, |
| sizeof(void *) *nr); |
| |
| from->avail -= nr; |
| to->avail += nr; |
| to->touched = 1; |
| return nr; |
| } |
| |
| #ifndef CONFIG_NUMA |
| |
| #define drain_alien_cache(cachep, alien) do { } while (0) |
| #define reap_alien(cachep, l3) do { } while (0) |
| |
| static inline struct array_cache **alloc_alien_cache(int node, int limit) |
| { |
| return (struct array_cache **)BAD_ALIEN_MAGIC; |
| } |
| |
| static inline void free_alien_cache(struct array_cache **ac_ptr) |
| { |
| } |
| |
| static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) |
| { |
| return 0; |
| } |
| |
| static inline void *alternate_node_alloc(struct kmem_cache *cachep, |
| gfp_t flags) |
| { |
| return NULL; |
| } |
| |
| static inline void *____cache_alloc_node(struct kmem_cache *cachep, |
| gfp_t flags, int nodeid) |
| { |
| return NULL; |
| } |
| |
| #else /* CONFIG_NUMA */ |
| |
| static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int); |
| static void *alternate_node_alloc(struct kmem_cache *, gfp_t); |
| |
| static struct array_cache **alloc_alien_cache(int node, int limit) |
| { |
| struct array_cache **ac_ptr; |
| int memsize = sizeof(void *) * nr_node_ids; |
| int i; |
| |
| if (limit > 1) |
| limit = 12; |
| ac_ptr = kmalloc_node(memsize, GFP_KERNEL, node); |
| if (ac_ptr) { |
| for_each_node(i) { |
| if (i == node || !node_online(i)) { |
| ac_ptr[i] = NULL; |
| continue; |
| } |
| ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d); |
| if (!ac_ptr[i]) { |
| for (i--; i <= 0; i--) |
| kfree(ac_ptr[i]); |
| kfree(ac_ptr); |
| return NULL; |
| } |
| } |
| } |
| return ac_ptr; |
| } |
| |
| static void free_alien_cache(struct array_cache **ac_ptr) |
| { |
| int i; |
| |
| if (!ac_ptr) |
| return; |
| for_each_node(i) |
| kfree(ac_ptr[i]); |
| kfree(ac_ptr); |
| } |
| |
| static void __drain_alien_cache(struct kmem_cache *cachep, |
| struct array_cache *ac, int node) |
| { |
| struct kmem_list3 *rl3 = cachep->nodelists[node]; |
| |
| if (ac->avail) { |
| spin_lock(&rl3->list_lock); |
| /* |
| * Stuff objects into the remote nodes shared array first. |
| * That way we could avoid the overhead of putting the objects |
| * into the free lists and getting them back later. |
| */ |
| if (rl3->shared) |
| transfer_objects(rl3->shared, ac, ac->limit); |
| |
| free_block(cachep, ac->entry, ac->avail, node); |
| ac->avail = 0; |
| spin_unlock(&rl3->list_lock); |
| } |
| } |
| |
| /* |
| * Called from cache_reap() to regularly drain alien caches round robin. |
| */ |
| static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3) |
| { |
| int node = __get_cpu_var(reap_node); |
| |
| if (l3->alien) { |
| struct array_cache *ac = l3->alien[node]; |
| |
| if (ac && ac->avail && spin_trylock_irq(&ac->lock)) { |
| __drain_alien_cache(cachep, ac, node); |
| spin_unlock_irq(&ac->lock); |
| } |
| } |
| } |
| |
| static void drain_alien_cache(struct kmem_cache *cachep, |
| struct array_cache **alien) |
| { |
| int i = 0; |
| struct array_cache *ac; |
| unsigned long flags; |
| |
| for_each_online_node(i) { |
| ac = alien[i]; |
| if (ac) { |
| spin_lock_irqsave(&ac->lock, flags); |
| __drain_alien_cache(cachep, ac, i); |
| spin_unlock_irqrestore(&ac->lock, flags); |
| } |
| } |
| } |
| |
| static inline int cache_free_alien(struct kmem_cache *cachep, void *objp) |
| { |
| struct slab *slabp = virt_to_slab(objp); |
| int nodeid = slabp->nodeid; |
| struct kmem_list3 *l3; |
| struct array_cache *alien = NULL; |
| int node; |
| |
| node = numa_node_id(); |
| |
| /* |
| * Make sure we are not freeing a object from another node to the array |
| * cache on this cpu. |
| */ |
| if (likely(slabp->nodeid == node)) |
| return 0; |
| |
| l3 = cachep->nodelists[node]; |
| STATS_INC_NODEFREES(cachep); |
| if (l3->alien && l3->alien[nodeid]) { |
| alien = l3->alien[nodeid]; |
| spin_lock(&alien->lock); |
| if (unlikely(alien->avail == alien->limit)) { |
| STATS_INC_ACOVERFLOW(cachep); |
| __drain_alien_cache(cachep, alien, nodeid); |
| } |
| alien->entry[alien->avail++] = objp; |
| spin_unlock(&alien->lock); |
| } else { |
| spin_lock(&(cachep->nodelists[nodeid])->list_lock); |
| free_block(cachep, &objp, 1, nodeid); |
| spin_unlock(&(cachep->nodelists[nodeid])->list_lock); |
| } |
| return 1; |
| } |
| #endif |
| |
| static int __cpuinit cpuup_callback(struct notifier_block *nfb, |
| unsigned long action, void *hcpu) |
| { |
| long cpu = (long)hcpu; |
| struct kmem_cache *cachep; |
| struct kmem_list3 *l3 = NULL; |
| int node = cpu_to_node(cpu); |
| int memsize = sizeof(struct kmem_list3); |
| |
| switch (action) { |
| case CPU_LOCK_ACQUIRE: |
| mutex_lock(&cache_chain_mutex); |
| break; |
| case CPU_UP_PREPARE: |
| case CPU_UP_PREPARE_FROZEN: |
| /* |
| * We need to do this right in the beginning since |
| * alloc_arraycache's are going to use this list. |
| * kmalloc_node allows us to add the slab to the right |
| * kmem_list3 and not this cpu's kmem_list3 |
| */ |
| |
| list_for_each_entry(cachep, &cache_chain, next) { |
| /* |
| * Set up the size64 kmemlist for cpu before we can |
| * begin anything. Make sure some other cpu on this |
| * node has not already allocated this |
| */ |
| if (!cachep->nodelists[node]) { |
| l3 = kmalloc_node(memsize, GFP_KERNEL, node); |
| if (!l3) |
| goto bad; |
| kmem_list3_init(l3); |
| l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + |
| ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
| |
| /* |
| * The l3s don't come and go as CPUs come and |
| * go. cache_chain_mutex is sufficient |
| * protection here. |
| */ |
| cachep->nodelists[node] = l3; |
| } |
| |
| spin_lock_irq(&cachep->nodelists[node]->list_lock); |
| cachep->nodelists[node]->free_limit = |
| (1 + nr_cpus_node(node)) * |
| cachep->batchcount + cachep->num; |
| spin_unlock_irq(&cachep->nodelists[node]->list_lock); |
| } |
| |
| /* |
| * Now we can go ahead with allocating the shared arrays and |
| * array caches |
| */ |
| list_for_each_entry(cachep, &cache_chain, next) { |
| struct array_cache *nc; |
| struct array_cache *shared = NULL; |
| struct array_cache **alien = NULL; |
| |
| nc = alloc_arraycache(node, cachep->limit, |
| cachep->batchcount); |
| if (!nc) |
| goto bad; |
| if (cachep->shared) { |
| shared = alloc_arraycache(node, |
| cachep->shared * cachep->batchcount, |
| 0xbaadf00d); |
| if (!shared) |
| goto bad; |
| } |
| if (use_alien_caches) { |
| alien = alloc_alien_cache(node, cachep->limit); |
| if (!alien) |
| goto bad; |
| } |
| cachep->array[cpu] = nc; |
| l3 = cachep->nodelists[node]; |
| BUG_ON(!l3); |
| |
| spin_lock_irq(&l3->list_lock); |
| if (!l3->shared) { |
| /* |
| * We are serialised from CPU_DEAD or |
| * CPU_UP_CANCELLED by the cpucontrol lock |
| */ |
| l3->shared = shared; |
| shared = NULL; |
| } |
| #ifdef CONFIG_NUMA |
| if (!l3->alien) { |
| l3->alien = alien; |
| alien = NULL; |
| } |
| #endif |
| spin_unlock_irq(&l3->list_lock); |
| kfree(shared); |
| free_alien_cache(alien); |
| } |
| break; |
| case CPU_ONLINE: |
| case CPU_ONLINE_FROZEN: |
| start_cpu_timer(cpu); |
| break; |
| #ifdef CONFIG_HOTPLUG_CPU |
| case CPU_DOWN_PREPARE: |
| case CPU_DOWN_PREPARE_FROZEN: |
| /* |
| * Shutdown cache reaper. Note that the cache_chain_mutex is |
| * held so that if cache_reap() is invoked it cannot do |
| * anything expensive but will only modify reap_work |
| * and reschedule the timer. |
| */ |
| cancel_rearming_delayed_work(&per_cpu(reap_work, cpu)); |
| /* Now the cache_reaper is guaranteed to be not running. */ |
| per_cpu(reap_work, cpu).work.func = NULL; |
| break; |
| case CPU_DOWN_FAILED: |
| case CPU_DOWN_FAILED_FROZEN: |
| start_cpu_timer(cpu); |
| break; |
| case CPU_DEAD: |
| case CPU_DEAD_FROZEN: |
| /* |
| * Even if all the cpus of a node are down, we don't free the |
| * kmem_list3 of any cache. This to avoid a race between |
| * cpu_down, and a kmalloc allocation from another cpu for |
| * memory from the node of the cpu going down. The list3 |
| * structure is usually allocated from kmem_cache_create() and |
| * gets destroyed at kmem_cache_destroy(). |
| */ |
| /* fall thru */ |
| #endif |
| case CPU_UP_CANCELED: |
| case CPU_UP_CANCELED_FROZEN: |
| list_for_each_entry(cachep, &cache_chain, next) { |
| struct array_cache *nc; |
| struct array_cache *shared; |
| struct array_cache **alien; |
| cpumask_t mask; |
| |
| mask = node_to_cpumask(node); |
| /* cpu is dead; no one can alloc from it. */ |
| nc = cachep->array[cpu]; |
| cachep->array[cpu] = NULL; |
| l3 = cachep->nodelists[node]; |
| |
| if (!l3) |
| goto free_array_cache; |
| |
| spin_lock_irq(&l3->list_lock); |
| |
| /* Free limit for this kmem_list3 */ |
| l3->free_limit -= cachep->batchcount; |
| if (nc) |
| free_block(cachep, nc->entry, nc->avail, node); |
| |
| if (!cpus_empty(mask)) { |
| spin_unlock_irq(&l3->list_lock); |
| goto free_array_cache; |
| } |
| |
| shared = l3->shared; |
| if (shared) { |
| free_block(cachep, shared->entry, |
| shared->avail, node); |
| l3->shared = NULL; |
| } |
| |
| alien = l3->alien; |
| l3->alien = NULL; |
| |
| spin_unlock_irq(&l3->list_lock); |
| |
| kfree(shared); |
| if (alien) { |
| drain_alien_cache(cachep, alien); |
| free_alien_cache(alien); |
| } |
| free_array_cache: |
| kfree(nc); |
| } |
| /* |
| * In the previous loop, all the objects were freed to |
| * the respective cache's slabs, now we can go ahead and |
| * shrink each nodelist to its limit. |
| */ |
| list_for_each_entry(cachep, &cache_chain, next) { |
| l3 = cachep->nodelists[node]; |
| if (!l3) |
| continue; |
| drain_freelist(cachep, l3, l3->free_objects); |
| } |
| break; |
| case CPU_LOCK_RELEASE: |
| mutex_unlock(&cache_chain_mutex); |
| break; |
| } |
| return NOTIFY_OK; |
| bad: |
| return NOTIFY_BAD; |
| } |
| |
| static struct notifier_block __cpuinitdata cpucache_notifier = { |
| &cpuup_callback, NULL, 0 |
| }; |
| |
| /* |
| * swap the static kmem_list3 with kmalloced memory |
| */ |
| static void init_list(struct kmem_cache *cachep, struct kmem_list3 *list, |
| int nodeid) |
| { |
| struct kmem_list3 *ptr; |
| |
| ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid); |
| BUG_ON(!ptr); |
| |
| local_irq_disable(); |
| memcpy(ptr, list, sizeof(struct kmem_list3)); |
| /* |
| * Do not assume that spinlocks can be initialized via memcpy: |
| */ |
| spin_lock_init(&ptr->list_lock); |
| |
| MAKE_ALL_LISTS(cachep, ptr, nodeid); |
| cachep->nodelists[nodeid] = ptr; |
| local_irq_enable(); |
| } |
| |
| /* |
| * Initialisation. Called after the page allocator have been initialised and |
| * before smp_init(). |
| */ |
| void __init kmem_cache_init(void) |
| { |
| size_t left_over; |
| struct cache_sizes *sizes; |
| struct cache_names *names; |
| int i; |
| int order; |
| int node; |
| |
| if (num_possible_nodes() == 1) |
| use_alien_caches = 0; |
| |
| for (i = 0; i < NUM_INIT_LISTS; i++) { |
| kmem_list3_init(&initkmem_list3[i]); |
| if (i < MAX_NUMNODES) |
| cache_cache.nodelists[i] = NULL; |
| } |
| |
| /* |
| * Fragmentation resistance on low memory - only use bigger |
| * page orders on machines with more than 32MB of memory. |
| */ |
| if (num_physpages > (32 << 20) >> PAGE_SHIFT) |
| slab_break_gfp_order = BREAK_GFP_ORDER_HI; |
| |
| /* Bootstrap is tricky, because several objects are allocated |
| * from caches that do not exist yet: |
| * 1) initialize the cache_cache cache: it contains the struct |
| * kmem_cache structures of all caches, except cache_cache itself: |
| * cache_cache is statically allocated. |
| * Initially an __init data area is used for the head array and the |
| * kmem_list3 structures, it's replaced with a kmalloc allocated |
| * array at the end of the bootstrap. |
| * 2) Create the first kmalloc cache. |
| * The struct kmem_cache for the new cache is allocated normally. |
| * An __init data area is used for the head array. |
| * 3) Create the remaining kmalloc caches, with minimally sized |
| * head arrays. |
| * 4) Replace the __init data head arrays for cache_cache and the first |
| * kmalloc cache with kmalloc allocated arrays. |
| * 5) Replace the __init data for kmem_list3 for cache_cache and |
| * the other cache's with kmalloc allocated memory. |
| * 6) Resize the head arrays of the kmalloc caches to their final sizes. |
| */ |
| |
| node = numa_node_id(); |
| |
| /* 1) create the cache_cache */ |
| INIT_LIST_HEAD(&cache_chain); |
| list_add(&cache_cache.next, &cache_chain); |
| cache_cache.colour_off = cache_line_size(); |
| cache_cache.array[smp_processor_id()] = &initarray_cache.cache; |
| cache_cache.nodelists[node] = &initkmem_list3[CACHE_CACHE]; |
| |
| /* |
| * struct kmem_cache size depends on nr_node_ids, which |
| * can be less than MAX_NUMNODES. |
| */ |
| cache_cache.buffer_size = offsetof(struct kmem_cache, nodelists) + |
| nr_node_ids * sizeof(struct kmem_list3 *); |
| #if DEBUG |
| cache_cache.obj_size = cache_cache.buffer_size; |
| #endif |
| cache_cache.buffer_size = ALIGN(cache_cache.buffer_size, |
| cache_line_size()); |
| cache_cache.reciprocal_buffer_size = |
| reciprocal_value(cache_cache.buffer_size); |
| |
| for (order = 0; order < MAX_ORDER; order++) { |
| cache_estimate(order, cache_cache.buffer_size, |
| cache_line_size(), 0, &left_over, &cache_cache.num); |
| if (cache_cache.num) |
| break; |
| } |
| BUG_ON(!cache_cache.num); |
| cache_cache.gfporder = order; |
| cache_cache.colour = left_over / cache_cache.colour_off; |
| cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) + |
| sizeof(struct slab), cache_line_size()); |
| |
| /* 2+3) create the kmalloc caches */ |
| sizes = malloc_sizes; |
| names = cache_names; |
| |
| /* |
| * Initialize the caches that provide memory for the array cache and the |
| * kmem_list3 structures first. Without this, further allocations will |
| * bug. |
| */ |
| |
| 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, |
| NULL, NULL); |
| |
| if (INDEX_AC != INDEX_L3) { |
| sizes[INDEX_L3].cs_cachep = |
| kmem_cache_create(names[INDEX_L3].name, |
| sizes[INDEX_L3].cs_size, |
| ARCH_KMALLOC_MINALIGN, |
| ARCH_KMALLOC_FLAGS|SLAB_PANIC, |
| NULL, NULL); |
| } |
| |
| slab_early_init = 0; |
| |
| while (sizes->cs_size != ULONG_MAX) { |
| /* |
| * For performance, all the general caches are L1 aligned. |
| * This should be particularly beneficial on SMP boxes, as it |
| * eliminates "false sharing". |
| * Note for systems short on memory removing the alignment will |
| * allow tighter packing of the smaller caches. |
| */ |
| if (!sizes->cs_cachep) { |
| sizes->cs_cachep = kmem_cache_create(names->name, |
| sizes->cs_size, |
| ARCH_KMALLOC_MINALIGN, |
| ARCH_KMALLOC_FLAGS|SLAB_PANIC, |
| NULL, NULL); |
| } |
| #ifdef CONFIG_ZONE_DMA |
| sizes->cs_dmacachep = kmem_cache_create( |
| names->name_dma, |
| sizes->cs_size, |
| ARCH_KMALLOC_MINALIGN, |
| ARCH_KMALLOC_FLAGS|SLAB_CACHE_DMA| |
| SLAB_PANIC, |
| NULL, NULL); |
| #endif |
| sizes++; |
| names++; |
| } |
| /* 4) Replace the bootstrap head arrays */ |
| { |
| struct array_cache *ptr; |
| |
| ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
| |
| local_irq_disable(); |
| BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache); |
| memcpy(ptr, cpu_cache_get(&cache_cache), |
| sizeof(struct arraycache_init)); |
| /* |
| * Do not assume that spinlocks can be initialized via memcpy: |
| */ |
| spin_lock_init(&ptr->lock); |
| |
| cache_cache.array[smp_processor_id()] = ptr; |
| local_irq_enable(); |
| |
| ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
| |
| local_irq_disable(); |
| BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep) |
| != &initarray_generic.cache); |
| memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep), |
| sizeof(struct arraycache_init)); |
| /* |
| * Do not assume that spinlocks can be initialized via memcpy: |
| */ |
| spin_lock_init(&ptr->lock); |
| |
| malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] = |
| ptr; |
| local_irq_enable(); |
| } |
| /* 5) Replace the bootstrap kmem_list3's */ |
| { |
| int nid; |
| |
| /* Replace the static kmem_list3 structures for the boot cpu */ |
| init_list(&cache_cache, &initkmem_list3[CACHE_CACHE], node); |
| |
| for_each_online_node(nid) { |
| init_list(malloc_sizes[INDEX_AC].cs_cachep, |
| &initkmem_list3[SIZE_AC + nid], nid); |
| |
| if (INDEX_AC != INDEX_L3) { |
| init_list(malloc_sizes[INDEX_L3].cs_cachep, |
| &initkmem_list3[SIZE_L3 + nid], nid); |
| } |
| } |
| } |
| |
| /* 6) resize the head arrays to their final sizes */ |
| { |
| struct kmem_cache *cachep; |
| mutex_lock(&cache_chain_mutex); |
| list_for_each_entry(cachep, &cache_chain, next) |
| if (enable_cpucache(cachep)) |
| BUG(); |
| mutex_unlock(&cache_chain_mutex); |
| } |
| |
| /* Annotate slab for lockdep -- annotate the malloc caches */ |
| init_lock_keys(); |
| |
| |
| /* Done! */ |
| g_cpucache_up = FULL; |
| |
| /* |
| * Register a cpu startup notifier callback that initializes |
| * cpu_cache_get for all new cpus |
| */ |
| register_cpu_notifier(&cpucache_notifier); |
| |
| /* |
| * The reap timers are started later, with a module init call: That part |
| * of the kernel is not yet operational. |
| */ |
| } |
| |
| static int __init cpucache_init(void) |
| { |
| int cpu; |
| |
| /* |
| * Register the timers that return unneeded pages to the page allocator |
| */ |
| for_each_online_cpu(cpu) |
| start_cpu_timer(cpu); |
| return 0; |
| } |
| __initcall(cpucache_init); |
| |
| /* |
| * Interface to system's page allocator. No need to hold the cache-lock. |
| * |
| * If we requested dmaable memory, we will get it. Even if we |
| * 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) |
| { |
| 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->gfpflags; |
| |
| page = alloc_pages_node(nodeid, flags, cachep->gfporder); |
| if (!page) |
| return NULL; |
| |
| nr_pages = (1 << cachep->gfporder); |
| if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
| add_zone_page_state(page_zone(page), |
| NR_SLAB_RECLAIMABLE, nr_pages); |
| else |
| add_zone_page_state(page_zone(page), |
| NR_SLAB_UNRECLAIMABLE, nr_pages); |
| for (i = 0; i < nr_pages; i++) |
| __SetPageSlab(page + i); |
| return page_address(page); |
| } |
| |
| /* |
| * Interface to system's page release. |
| */ |
| static void kmem_freepages(struct kmem_cache *cachep, void *addr) |
| { |
| unsigned long i = (1 << cachep->gfporder); |
| struct page *page = virt_to_page(addr); |
| const unsigned long nr_freed = i; |
| |
| if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
| sub_zone_page_state(page_zone(page), |
| NR_SLAB_RECLAIMABLE, nr_freed); |
| else |
| sub_zone_page_state(page_zone(page), |
| NR_SLAB_UNRECLAIMABLE, nr_freed); |
| while (i--) { |
| BUG_ON(!PageSlab(page)); |
| __ClearPageSlab(page); |
| page++; |
| } |
| if (current->reclaim_state) |
| current->reclaim_state->reclaimed_slab += nr_freed; |
| free_pages((unsigned long)addr, 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; |
| |
| kmem_freepages(cachep, slab_rcu->addr); |
| if (OFF_SLAB(cachep)) |
| kmem_cache_free(cachep->slabp_cache, slab_rcu); |
| } |
| |
| #if DEBUG |
| |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr, |
| unsigned long caller) |
| { |
| int size = obj_size(cachep); |
| |
| addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)]; |
| |
| if (size < 5 * sizeof(unsigned long)) |
| return; |
| |
| *addr++ = 0x12345678; |
| *addr++ = caller; |
| *addr++ = smp_processor_id(); |
| size -= 3 * sizeof(unsigned long); |
| { |
| unsigned long *sptr = &caller; |
| unsigned long svalue; |
| |
| while (!kstack_end(sptr)) { |
| svalue = *sptr++; |
| if (kernel_text_address(svalue)) { |
| *addr++ = svalue; |
| size -= sizeof(unsigned long); |
| if (size <= sizeof(unsigned long)) |
| break; |
| } |
| } |
| |
| } |
| *addr++ = 0x87654321; |
| } |
| #endif |
| |
| static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) |
| { |
| int size = obj_size(cachep); |
| addr = &((char *)addr)[obj_offset(cachep)]; |
| |
| memset(addr, val, size); |
| *(unsigned char *)(addr + size - 1) = POISON_END; |
| } |
| |
| static void dump_line(char *data, int offset, int limit) |
| { |
| int i; |
| unsigned char error = 0; |
| int bad_count = 0; |
| |
| printk(KERN_ERR "%03x:", offset); |
| for (i = 0; i < limit; i++) { |
| if (data[offset + i] != POISON_FREE) { |
| error = data[offset + i]; |
| bad_count++; |
| } |
| printk(" %02x", (unsigned char)data[offset + i]); |
| } |
| printk("\n"); |
| |
| if (bad_count == 1) { |
| error ^= POISON_FREE; |
| if (!(error & (error - 1))) { |
| printk(KERN_ERR "Single bit error detected. Probably " |
| "bad RAM.\n"); |
| #ifdef CONFIG_X86 |
| printk(KERN_ERR "Run memtest86+ or a similar memory " |
| "test tool.\n"); |
| #else |
| printk(KERN_ERR "Run a memory test tool.\n"); |
| #endif |
| } |
| } |
| } |
| #endif |
| |
| #if DEBUG |
| |
| static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) |
| { |
| int i, size; |
| char *realobj; |
| |
| if (cachep->flags & SLAB_RED_ZONE) { |
| printk(KERN_ERR "Redzone: 0x%llx/0x%llx.\n", |
| *dbg_redzone1(cachep, objp), |
| *dbg_redzone2(cachep, objp)); |
| } |
| |
| if (cachep->flags & SLAB_STORE_USER) { |
| printk(KERN_ERR "Last user: [<%p>]", |
| *dbg_userword(cachep, objp)); |
| print_symbol("(%s)", |
| (unsigned long)*dbg_userword(cachep, objp)); |
| printk("\n"); |
| } |
| realobj = (char *)objp + obj_offset(cachep); |
| size = obj_size(cachep); |
| for (i = 0; i < size && lines; i += 16, lines--) { |
| int limit; |
| limit = 16; |
| if (i + limit > size) |
| limit = size - i; |
| dump_line(realobj, i, limit); |
| } |
| } |
| |
| static void check_poison_obj(struct kmem_cache *cachep, void *objp) |
| { |
| char *realobj; |
| int size, i; |
| int lines = 0; |
| |
| realobj = (char *)objp + obj_offset(cachep); |
| size = obj_size(cachep); |
| |
| for (i = 0; i < size; i++) { |
| char exp = POISON_FREE; |
| if (i == size - 1) |
| exp = POISON_END; |
| if (realobj[i] != exp) { |
| int limit; |
| /* Mismatch ! */ |
| /* Print header */ |
| if (lines == 0) { |
| printk(KERN_ERR |
| "Slab corruption: %s start=%p, len=%d\n", |
| cachep->name, realobj, size); |
| print_objinfo(cachep, objp, 0); |
| } |
| /* Hexdump the affected line */ |
| i = (i / 16) * 16; |
| limit = 16; |
| if (i + limit > size) |
| limit = size - i; |
| dump_line(realobj, i, limit); |
| i += 16; |
| lines++; |
| /* Limit to 5 lines */ |
| if (lines > 5) |
| break; |
| } |
| } |
| if (lines != 0) { |
| /* Print some data about the neighboring objects, if they |
| * exist: |
| */ |
| struct slab *slabp = virt_to_slab(objp); |
| unsigned int objnr; |
| |
| objnr = obj_to_index(cachep, slabp, objp); |
| if (objnr) { |
| objp = index_to_obj(cachep, slabp, 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); |
| realobj = (char *)objp + obj_offset(cachep); |
| printk(KERN_ERR "Next obj: start=%p, len=%d\n", |
| realobj, size); |
| print_objinfo(cachep, objp, 2); |
| } |
| } |
| } |
| #endif |
| |
| #if DEBUG |
| /** |
| * slab_destroy_objs - destroy a slab and its objects |
| * @cachep: cache pointer being destroyed |
| * @slabp: slab pointer being destroyed |
| * |
| * Call the registered destructor for each object in a slab that is being |
| * destroyed. |
| */ |
| static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
| { |
| int i; |
| for (i = 0; i < cachep->num; i++) { |
| void *objp = index_to_obj(cachep, slabp, i); |
| |
| if (cachep->flags & SLAB_POISON) { |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| if (cachep->buffer_size % PAGE_SIZE == 0 && |
| OFF_SLAB(cachep)) |
| kernel_map_pages(virt_to_page(objp), |
| cachep->buffer_size / PAGE_SIZE, 1); |
| else |
| check_poison_obj(cachep, objp); |
| #else |
| check_poison_obj(cachep, objp); |
| #endif |
| } |
| if (cachep->flags & SLAB_RED_ZONE) { |
| if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
| slab_error(cachep, "start of a freed object " |
| "was overwritten"); |
| if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
| slab_error(cachep, "end of a freed object " |
| "was overwritten"); |
| } |
| } |
| } |
| #else |
| static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
| { |
| } |
| #endif |
| |
| /** |
| * slab_destroy - destroy and release all objects in a slab |
| * @cachep: cache pointer being destroyed |
| * @slabp: slab pointer being destroyed |
| * |
| * Destroy all the objs in a slab, and release the mem back to the system. |
| * 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) |
| { |
| void *addr = slabp->s_mem - slabp->colouroff; |
| |
| slab_destroy_objs(cachep, slabp); |
| if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) { |
| struct slab_rcu *slab_rcu; |
| |
| 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); |
| } |
| } |
| |
| /* |
| * For setting up all the kmem_list3s for cache whose buffer_size is same as |
| * size of kmem_list3. |
| */ |
| static void __init set_up_list3s(struct kmem_cache *cachep, int index) |
| { |
| int node; |
| |
| for_each_online_node(node) { |
| cachep->nodelists[node] = &initkmem_list3[index + node]; |
| cachep->nodelists[node]->next_reap = jiffies + |
| REAPTIMEOUT_LIST3 + |
| ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
| } |
| } |
| |
| static void __kmem_cache_destroy(struct kmem_cache *cachep) |
| { |
| int i; |
| struct kmem_list3 *l3; |
| |
| for_each_online_cpu(i) |
| kfree(cachep->array[i]); |
| |
| /* NUMA: free the list3 structures */ |
| for_each_online_node(i) { |
| l3 = cachep->nodelists[i]; |
| if (l3) { |
| kfree(l3->shared); |
| free_alien_cache(l3->alien); |
| kfree(l3); |
| } |
| } |
| kmem_cache_free(&cache_cache, cachep); |
| } |
| |
| |
| /** |
| * calculate_slab_order - calculate size (page order) of slabs |
| * @cachep: pointer to the cache that is being created |
| * @size: size of objects to be created in this cache. |
| * @align: required alignment for the objects. |
| * @flags: slab allocation flags |
| * |
| * Also calculates the number of objects per slab. |
| * |
| * This could be made much more intelligent. For now, try to avoid using |
| * high order pages for slabs. When the gfp() functions are more friendly |
| * towards high-order requests, this should be changed. |
| */ |
| static size_t calculate_slab_order(struct kmem_cache *cachep, |
| size_t size, size_t align, unsigned long flags) |
| { |
| unsigned long offslab_limit; |
| size_t left_over = 0; |
| int gfporder; |
| |
| for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) { |
| unsigned int num; |
| size_t remainder; |
| |
| cache_estimate(gfporder, size, align, flags, &remainder, &num); |
| if (!num) |
| continue; |
| |
| if (flags & CFLGS_OFF_SLAB) { |
| /* |
| * Max number of objs-per-slab for caches which |
| * 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); |
| |
| if (num > offslab_limit) |
| break; |
| } |
| |
| /* Found something acceptable - save it away */ |
| cachep->num = num; |
| cachep->gfporder = gfporder; |
| left_over = remainder; |
| |
| /* |
| * A VFS-reclaimable slab tends to have most allocations |
| * as GFP_NOFS and we really don't want to have to be allocating |
| * higher-order pages when we are unable to shrink dcache. |
| */ |
| if (flags & SLAB_RECLAIM_ACCOUNT) |
| break; |
| |
| /* |
| * Large number of objects is good, but very large slabs are |
| * currently bad for the gfp()s. |
| */ |
| if (gfporder >= slab_break_gfp_order) |
| break; |
| |
| /* |
| * Acceptable internal fragmentation? |
| */ |
| if (left_over * 8 <= (PAGE_SIZE << gfporder)) |
| break; |
| } |
| return left_over; |
| } |
| |
| static int __init_refok setup_cpu_cache(struct kmem_cache *cachep) |
| { |
| if (g_cpucache_up == FULL) |
| return enable_cpucache(cachep); |
| |
| if (g_cpucache_up == NONE) { |
| /* |
| * Note: the first kmem_cache_create must create the cache |
| * that's used by kmalloc(24), otherwise the creation of |
| * further caches will BUG(). |
| */ |
| cachep->array[smp_processor_id()] = &initarray_generic.cache; |
| |
| /* |
| * If the cache that's used by kmalloc(sizeof(kmem_list3)) is |
| * the first cache, then we need to set up all its list3s, |
| * otherwise the creation of further caches will BUG(). |
| */ |
| set_up_list3s(cachep, SIZE_AC); |
| if (INDEX_AC == INDEX_L3) |
| g_cpucache_up = PARTIAL_L3; |
| else |
| g_cpucache_up = PARTIAL_AC; |
| } else { |
| cachep->array[smp_processor_id()] = |
| kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
| |
| if (g_cpucache_up == PARTIAL_AC) { |
| set_up_list3s(cachep, SIZE_L3); |
| g_cpucache_up = PARTIAL_L3; |
| } else { |
| int node; |
| for_each_online_node(node) { |
| cachep->nodelists[node] = |
| kmalloc_node(sizeof(struct kmem_list3), |
| GFP_KERNEL, node); |
| BUG_ON(!cachep->nodelists[node]); |
| kmem_list3_init(cachep->nodelists[node]); |
| } |
| } |
| } |
| cachep->nodelists[numa_node_id()]->next_reap = |
| jiffies + REAPTIMEOUT_LIST3 + |
| ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
| |
| cpu_cache_get(cachep)->avail = 0; |
| cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; |
| cpu_cache_get(cachep)->batchcount = 1; |
| cpu_cache_get(cachep)->touched = 0; |
| cachep->batchcount = 1; |
| cachep->limit = BOOT_CPUCACHE_ENTRIES; |
| return 0; |
| } |
| |
| /** |
| * 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. |
| * @dtor: A destructor for the objects (not implemented anymore). |
| * |
| * Returns a ptr to the cache on success, NULL on failure. |
| * Cannot be called within a int, but can be interrupted. |
| * The @ctor is run when new pages are allocated by the cache |
| * and the @dtor is run before the pages are handed back. |
| * |
| * @name must be valid until the cache is destroyed. This implies that |
| * the module calling this has to destroy the cache before getting unloaded. |
| * |
| * 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 *, unsigned long), |
| void (*dtor)(void*, struct kmem_cache *, unsigned long)) |
| { |
| size_t left_over, slab_size, ralign; |
| struct kmem_cache *cachep = NULL, *pc; |
| |
| /* |
| * Sanity checks... these are all serious usage bugs. |
| */ |
| if (!name || in_interrupt() || (size < BYTES_PER_WORD) || |
| size > KMALLOC_MAX_SIZE || dtor) { |
| printk(KERN_ERR "%s: Early error in slab %s\n", __FUNCTION__, |
| name); |
| BUG(); |
| } |
| |
| /* |
| * We use cache_chain_mutex to ensure a consistent view of |
| * cpu_online_map as well. Please see cpuup_callback |
| */ |
| mutex_lock(&cache_chain_mutex); |
| |
| list_for_each_entry(pc, &cache_chain, next) { |
| 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(pc->name, tmp); |
| if (res) { |
| printk(KERN_ERR |
| "SLAB: cache with size %d has lost its name\n", |
| pc->buffer_size); |
| continue; |
| } |
| |
| if (!strcmp(pc->name, name)) { |
| printk(KERN_ERR |
| "kmem_cache_create: duplicate cache %s\n", name); |
| dump_stack(); |
| goto oops; |
| } |
| } |
| |
| #if DEBUG |
| WARN_ON(strchr(name, ' ')); /* It confuses parsers */ |
| #if FORCED_DEBUG |
| /* |
| * Enable redzoning and last user accounting, except for caches with |
| * large objects, if the increased size would increase the object size |
| * above the next power of two: caches with object sizes just above a |
| * power of two have a significant amount of internal fragmentation. |
| */ |
| if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN + |
| 2 * sizeof(unsigned long long))) |
| flags |= SLAB_RED_ZONE | SLAB_STORE_USER; |
| if (!(flags & SLAB_DESTROY_BY_RCU)) |
| flags |= SLAB_POISON; |
| #endif |
| if (flags & SLAB_DESTROY_BY_RCU) |
| BUG_ON(flags & SLAB_POISON); |
| #endif |
| /* |
| * Always checks flags, a caller might be expecting debug support which |
| * isn't available. |
| */ |
| BUG_ON(flags & ~CREATE_MASK); |
| |
| /* |
| * Check that size is in terms of words. This is needed to avoid |
| * unaligned accesses for some archs when redzoning is used, and makes |
| * sure any on-slab bufctl's are also correctly aligned. |
| */ |
| if (size & (BYTES_PER_WORD - 1)) { |
| size += (BYTES_PER_WORD - 1); |
| size &= ~(BYTES_PER_WORD - 1); |
| } |
| |
| /* calculate the final buffer alignment: */ |
| |
| /* 1) arch recommendation: can be overridden for debug */ |
| if (flags & SLAB_HWCACHE_ALIGN) { |
| /* |
| * Default alignment: as specified by the arch code. Except if |
| * an object is really small, then squeeze multiple objects into |
| * one cacheline. |
| */ |
| ralign = cache_line_size(); |
| while (size <= ralign / 2) |
| ralign /= 2; |
| } else { |
| ralign = BYTES_PER_WORD; |
| } |
| |
| /* |
| * Redzoning and user store require word alignment or possibly larger. |
| * Note this will be overridden by architecture or caller mandated |
| * alignment if either is greater than BYTES_PER_WORD. |
| */ |
| if (flags & SLAB_STORE_USER) |
| ralign = BYTES_PER_WORD; |
| |
| if (flags & SLAB_RED_ZONE) { |
| ralign = REDZONE_ALIGN; |
| /* If redzoning, ensure that the second redzone is suitably |
| * aligned, by adjusting the object size accordingly. */ |
| size += REDZONE_ALIGN - 1; |
| size &= ~(REDZONE_ALIGN - 1); |
| } |
| |
| /* 2) arch mandated alignment */ |
| if (ralign < ARCH_SLAB_MINALIGN) { |
| ralign = ARCH_SLAB_MINALIGN; |
| } |
| /* 3) caller mandated alignment */ |
| if (ralign < align) { |
| ralign = align; |
| } |
| /* disable debug if necessary */ |
| if (ralign > __alignof__(unsigned long long)) |
| flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
| /* |
| * 4) Store it. |
| */ |
| align = ralign; |
| |
| /* Get cache's description obj. */ |
| cachep = kmem_cache_zalloc(&cache_cache, GFP_KERNEL); |
| if (!cachep) |
| goto oops; |
| |
| #if DEBUG |
| cachep->obj_size = size; |
| |
| /* |
| * Both debugging options require word-alignment which is calculated |
| * into align above. |
| */ |
| if (flags & SLAB_RED_ZONE) { |
| /* add space for red zone words */ |
| 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 |
| * the real object. But if the second red zone needs to be |
| * aligned to 64 bits, we must allow that much space. |
| */ |
| if (flags & SLAB_RED_ZONE) |
| size += REDZONE_ALIGN; |
| else |
| size += BYTES_PER_WORD; |
| } |
| #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) |
| if (size >= malloc_sizes[INDEX_L3 + 1].cs_size |
| && cachep->obj_size > cache_line_size() && size < PAGE_SIZE) { |
| cachep->obj_offset += PAGE_SIZE - size; |
| size = PAGE_SIZE; |
| } |
| #endif |
| #endif |
| |
| /* |
| * Determine if the slab management is 'on' or 'off' slab. |
| * (bootstrapping cannot cope with offslab caches so don't do |
| * it too early on.) |
| */ |
| if ((size >= (PAGE_SIZE >> 3)) && !slab_early_init) |
| /* |
| * Size is large, assume best to place the slab management obj |
| * off-slab (should allow better packing of objs). |
| */ |
| flags |= CFLGS_OFF_SLAB; |
| |
| size = ALIGN(size, align); |
| |
| left_over = calculate_slab_order(cachep, size, align, flags); |
| |
| if (!cachep->num) { |
| printk(KERN_ERR |
| "kmem_cache_create: couldn't create cache %s.\n", name); |
| kmem_cache_free(&cache_cache, cachep); |
| cachep = NULL; |
| goto oops; |
| } |
| slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t) |
| + sizeof(struct slab), 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) { |
| flags &= ~CFLGS_OFF_SLAB; |
| left_over -= slab_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); |
| } |
| |
| cachep->colour_off = cache_line_size(); |
| /* Offset must be a multiple of the alignment. */ |
| if (cachep->colour_off < align) |
| cachep->colour_off = align; |
| cachep->colour = left_over / cachep->colour_off; |
| cachep->slab_size = slab_size; |
| cachep->flags = flags; |
| cachep->gfpflags = 0; |
| if (CONFIG_ZONE_DMA_FLAG && (flags & SLAB_CACHE_DMA)) |
| cachep->gfpflags |= GFP_DMA; |
| cachep->buffer_size = size; |
| cachep->reciprocal_buffer_size = reciprocal_value(size); |
| |
| if (flags & CFLGS_OFF_SLAB) { |
| cachep->slabp_cache = kmem_find_general_cachep(slab_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 |
| * PAGE_SIZE/8, and malloc_sizes gets created in ascending order, |
| * this should not happen at all. |
| * But leave a BUG_ON for some lucky dude. |
| */ |
| BUG_ON(ZERO_OR_NULL_PTR(cachep->slabp_cache)); |
| } |
| cachep->ctor = ctor; |
| cachep->name = name; |
| |
| if (setup_cpu_cache(cachep)) { |
| __kmem_cache_destroy(cachep); |
| cachep = NULL; |
| goto oops; |
| } |
| |
| /* cache setup completed, link it into the list */ |
| list_add(&cachep->next, &cache_chain); |
| oops: |
| if (!cachep && (flags & SLAB_PANIC)) |
| panic("kmem_cache_create(): failed to create slab `%s'\n", |
| name); |
| mutex_unlock(&cache_chain_mutex); |
| return cachep; |
| } |
| EXPORT_SYMBOL(kmem_cache_create); |
| |
| #if DEBUG |
| static void check_irq_off(void) |
| { |
| BUG_ON(!irqs_disabled()); |
| } |
| |
| static void check_irq_on(void) |
| { |
| BUG_ON(irqs_disabled()); |
| } |
| |
| static void check_spinlock_acquired(struct kmem_cache *cachep) |
| { |
| #ifdef CONFIG_SMP |
| check_irq_off(); |
| assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock); |
| #endif |
| } |
| |
| static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) |
| { |
| #ifdef CONFIG_SMP |
| check_irq_off(); |
| assert_spin_locked(&cachep->nodelists[node]->list_lock); |
| #endif |
| } |
| |
| #else |
| #define check_irq_off() do { } while(0) |
| #define check_irq_on() do { } while(0) |
| #define check_spinlock_acquired(x) do { } while(0) |
| #define check_spinlock_acquired_node(x, y) do { } while(0) |
| #endif |
| |
| static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, |
| struct array_cache *ac, |
| int force, int node); |
| |
| static void do_drain(void *arg) |
| { |
| struct kmem_cache *cachep = arg; |
| struct array_cache *ac; |
| int node = numa_node_id(); |
| |
| check_irq_off(); |
| ac = cpu_cache_get(cachep); |
| spin_lock(&cachep->nodelists[node]->list_lock); |
| free_block(cachep, ac->entry, ac->avail, node); |
| spin_unlock(&cachep->nodelists[node]->list_lock); |
| ac->avail = 0; |
| } |
| |
| static void drain_cpu_caches(struct kmem_cache *cachep) |
| { |
| struct kmem_list3 *l3; |
| int node; |
| |
| on_each_cpu(do_drain, cachep, 1, 1); |
| check_irq_on(); |
| for_each_online_node(node) { |
| l3 = cachep->nodelists[node]; |
| if (l3 && l3->alien) |
| drain_alien_cache(cachep, l3->alien); |
| } |
| |
| for_each_online_node(node) { |
| l3 = cachep->nodelists[node]; |
| if (l3) |
| drain_array(cachep, l3, l3->shared, 1, node); |
| } |
| } |
| |
| /* |
| * Remove slabs from the list of free slabs. |
| * Specify the number of slabs to drain in tofree. |
| * |
| * Returns the actual number of slabs released. |
| */ |
| static int drain_freelist(struct kmem_cache *cache, |
| struct kmem_list3 *l3, int tofree) |
| { |
| struct list_head *p; |
| int nr_freed; |
| struct slab *slabp; |
| |
| nr_freed = 0; |
| while (nr_freed < tofree && !list_empty(&l3->slabs_free)) { |
| |
| spin_lock_irq(&l3->list_lock); |
| p = l3->slabs_free.prev; |
| if (p == &l3->slabs_free) { |
| spin_unlock_irq(&l3->list_lock); |
| goto out; |
| } |
| |
| slabp = list_entry(p, struct slab, list); |
| #if DEBUG |
| BUG_ON(slabp->inuse); |
| #endif |
| list_del(&slabp->list); |
| /* |
| * Safe to drop the lock. The slab is no longer linked |
| * to the cache. |
| */ |
| l3->free_objects -= cache->num; |
| spin_unlock_irq(&l3->list_lock); |
| slab_destroy(cache, slabp); |
| nr_freed++; |
| } |
| out: |
| return nr_freed; |
| } |
| |
| /* Called with cache_chain_mutex held to protect against cpu hotplug */ |
| static int __cache_shrink(struct kmem_cache *cachep) |
| { |
| int ret = 0, i = 0; |
| struct kmem_list3 *l3; |
| |
| drain_cpu_caches(cachep); |
| |
| check_irq_on(); |
| for_each_online_node(i) { |
| l3 = cachep->nodelists[i]; |
| if (!l3) |
| continue; |
| |
| drain_freelist(cachep, l3, l3->free_objects); |
| |
| ret += !list_empty(&l3->slabs_full) || |
| !list_empty(&l3->slabs_partial); |
| } |
| return (ret ? 1 : 0); |
| } |
| |
| /** |
| * kmem_cache_shrink - Shrink a cache. |
| * @cachep: The cache to shrink. |
| * |
| * Releases as many slabs as possible for a cache. |
| * To help debugging, a zero exit status indicates all slabs were released. |
| */ |
| int kmem_cache_shrink(struct kmem_cache *cachep) |
| { |
| int ret; |
| BUG_ON(!cachep || in_interrupt()); |
| |
| mutex_lock(&cache_chain_mutex); |
| ret = __cache_shrink(cachep); |
| mutex_unlock(&cache_chain_mutex); |
| return ret; |
| } |
| EXPORT_SYMBOL(kmem_cache_shrink); |
| |
| /** |
| * kmem_cache_destroy - delete a cache |
| * @cachep: the cache to destroy |
| * |
| * Remove a &struct kmem_cache object from the slab cache. |
| * |
| * It is expected this function will be called by a module when it is |
| * unloaded. This will remove the cache completely, and avoid a duplicate |
| * cache being allocated each time a module is loaded and unloaded, if the |
| * module doesn't have persistent in-kernel storage across loads and unloads. |
| * |
| * The cache must be empty before calling this function. |
| * |
| * The caller must guarantee that noone will allocate memory from the cache |
| * during the kmem_cache_destroy(). |
| */ |
| void kmem_cache_destroy(struct kmem_cache *cachep) |
| { |
| BUG_ON(!cachep || in_interrupt()); |
| |
| /* Find the cache in the chain of caches. */ |
| mutex_lock(&cache_chain_mutex); |
| /* |
| * the chain is never empty, cache_cache is never destroyed |
| */ |
| list_del(&cachep->next); |
| if (__cache_shrink(cachep)) { |
| slab_error(cachep, "Can't free all objects"); |
| list_add(&cachep->next, &cache_chain); |
| mutex_unlock(&cache_chain_mutex); |
| return; |
| } |
| |
| if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) |
| synchronize_rcu(); |
| |
| __kmem_cache_destroy(cachep); |
| mutex_unlock(&cache_chain_mutex); |
| } |
| EXPORT_SYMBOL(kmem_cache_destroy); |
| |
| /* |
| * Get the memory for a slab management obj. |
| * For a slab cache when the slab descriptor is off-slab, slab descriptors |
| * always come from malloc_sizes caches. The slab descriptor cannot |
| * come from the same cache which is getting created because, |
| * when we are searching for an appropriate cache for these |
| * 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. |
| */ |
| static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp, |
| int colour_off, gfp_t local_flags, |
| int nodeid) |
| { |
| struct slab *slabp; |
| |
| if (OFF_SLAB(cachep)) { |
| /* Slab management obj is off-slab. */ |
| slabp = kmem_cache_alloc_node(cachep->slabp_cache, |
| local_flags & ~GFP_THISNODE, nodeid); |
| if (!slabp) |
| return NULL; |
| } else { |
| slabp = objp + colour_off; |
| colour_off += cachep->slab_size; |
| } |
| slabp->inuse = 0; |
| slabp->colouroff = colour_off; |
| slabp->s_mem = objp + colour_off; |
| slabp->nodeid = nodeid; |
| return slabp; |
| } |
| |
| static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp) |
| { |
| return (kmem_bufctl_t *) (slabp + 1); |
| } |
| |
| static void cache_init_objs(struct kmem_cache *cachep, |
| struct slab *slabp) |
| { |
| int i; |
| |
| for (i = 0; i < cachep->num; i++) { |
| void *objp = index_to_obj(cachep, slabp, i); |
| #if DEBUG |
| /* need to poison the objs? */ |
| if (cachep->flags & SLAB_POISON) |
| poison_obj(cachep, objp, POISON_FREE); |
| if (cachep->flags & SLAB_STORE_USER) |
| *dbg_userword(cachep, objp) = NULL; |
| |
| if (cachep->flags & SLAB_RED_ZONE) { |
| *dbg_redzone1(cachep, objp) = RED_INACTIVE; |
| *dbg_redzone2(cachep, objp) = RED_INACTIVE; |
| } |
| /* |
| * Constructors are not allowed to allocate memory from the same |
| * cache which they are a constructor for. Otherwise, deadlock. |
| * They must also be threaded. |
| */ |
| if (cachep->ctor && !(cachep->flags & SLAB_POISON)) |
| cachep->ctor(objp + obj_offset(cachep), cachep, |
| 0); |
| |
| if (cachep->flags & SLAB_RED_ZONE) { |
| if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
| slab_error(cachep, "constructor overwrote the" |
| " end of an object"); |
| if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
| slab_error(cachep, "constructor overwrote the" |
| " start of an object"); |
| } |
| if ((cachep->buffer_size % PAGE_SIZE) == 0 && |
| OFF_SLAB(cachep) && cachep->flags & SLAB_POISON) |
| kernel_map_pages(virt_to_page(objp), |
| cachep->buffer_size / PAGE_SIZE, 0); |
| #else |
| if (cachep->ctor) |
| cachep->ctor(objp, cachep, 0); |
| #endif |
| slab_bufctl(slabp)[i] = i + 1; |
| } |
| slab_bufctl(slabp)[i - 1] = BUFCTL_END; |
| slabp->free = 0; |
| } |
| |
| static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags) |
| { |
| if (CONFIG_ZONE_DMA_FLAG) { |
| if (flags & GFP_DMA) |
| BUG_ON(!(cachep->gfpflags & GFP_DMA)); |
| else |
| BUG_ON(cachep->gfpflags & GFP_DMA); |
| } |
| } |
| |
| static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, |
| int nodeid) |
| { |
| void *objp = index_to_obj(cachep, slabp, slabp->free); |
| kmem_bufctl_t next; |
| |
| slabp->inuse++; |
| next = slab_bufctl(slabp)[slabp->free]; |
| #if DEBUG |
| slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; |
| WARN_ON(slabp->nodeid != nodeid); |
| #endif |
| slabp->free = next; |
| |
| return objp; |
| } |
| |
| static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, |
| void *objp, int nodeid) |
| { |
| unsigned int objnr = obj_to_index(cachep, slabp, objp); |
| |
| #if DEBUG |
| /* Verify that the slab belongs to the intended node */ |
| WARN_ON(slabp->nodeid != nodeid); |
| |
| if (slab_bufctl(slabp)[objnr] + 1 <= SLAB_LIMIT + 1) { |
| 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--; |
| } |
| |
| /* |
| * Map pages beginning at addr to the given cache and slab. This is required |
| * for the slab allocator to be able to lookup the cache and slab of a |
| * virtual address for kfree, ksize, kmem_ptr_validate, and slab debugging. |
| */ |
| static void slab_map_pages(struct kmem_cache *cache, struct slab *slab, |
| void *addr) |
| { |
| int nr_pages; |
| struct page *page; |
| |
| page = virt_to_page(addr); |
| |
| nr_pages = 1; |
| if (likely(!PageCompound(page))) |
| nr_pages <<= cache->gfporder; |
| |
| do { |
| page_set_cache(page, cache); |
| page_set_slab(page, slab); |
| page++; |
| } while (--nr_pages); |
| } |
| |
| /* |
| * Grow (by 1) the number of slabs within a cache. This is called by |
| * 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) |
| { |
| struct slab *slabp; |
| size_t offset; |
| gfp_t local_flags; |
| struct kmem_list3 *l3; |
| |
| /* |
| * Be lazy and only check for valid flags here, keeping it out of the |
| * critical path in kmem_cache_alloc(). |
| */ |
| BUG_ON(flags & ~(GFP_DMA | GFP_LEVEL_MASK)); |
| |
| local_flags = (flags & GFP_LEVEL_MASK); |
| /* Take the l3 list lock to change the colour_next on this node */ |
| check_irq_off(); |
| l3 = cachep->nodelists[nodeid]; |
| spin_lock(&l3->list_lock); |
| |
| /* Get colour for the slab, and cal the next value. */ |
| offset = l3->colour_next; |
| l3->colour_next++; |
| if (l3->colour_next >= cachep->colour) |
| l3->colour_next = 0; |
| spin_unlock(&l3->list_lock); |
| |
| offset *= cachep->colour_off; |
| |
| if (local_flags & __GFP_WAIT) |
| local_irq_enable(); |
| |
| /* |
| * The test for missing atomic flag is performed here, rather than |
| * the more obvious place, simply to reduce the critical path length |
| * in kmem_cache_alloc(). If a caller is seriously mis-behaving they |
| * will eventually be caught here (where it matters). |
| */ |
| kmem_flagcheck(cachep, flags); |
| |
| /* |
| * Get mem for the objs. Attempt to allocate a physical page from |
| * 'nodeid'. |
| */ |
| if (!objp) |
| objp = kmem_getpages(cachep, flags, nodeid); |
| if (!objp) |
| goto failed; |
| |
| /* Get slab management. */ |
| slabp = alloc_slabmgmt(cachep, objp, offset, |
| local_flags & ~GFP_THISNODE, nodeid); |
| if (!slabp) |
| goto opps1; |
| |
| slabp->nodeid = nodeid; |
| slab_map_pages(cachep, slabp, objp); |
| |
| cache_init_objs(cachep, slabp); |
| |
| if (local_flags & __GFP_WAIT) |
| local_irq_disable(); |
| check_irq_off(); |
| spin_lock(&l3->list_lock); |
| |
| /* Make slab active. */ |
| list_add_tail(&slabp->list, &(l3->slabs_free)); |
| STATS_INC_GROWN(cachep); |
| l3->free_objects += cachep->num; |
| spin_unlock(&l3->list_lock); |
| return 1; |
| opps1: |
| kmem_freepages(cachep, objp); |
| failed: |
| if (local_flags & __GFP_WAIT) |
| local_irq_disable(); |
| return 0; |
| } |
| |
| #if DEBUG |
| |
| /* |
| * Perform extra freeing checks: |
| * - detect bad pointers. |
| * - POISON/RED_ZONE checking |
| */ |
| static void kfree_debugcheck(const void *objp) |
| { |
| if (!virt_addr_valid(objp)) { |
| printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n", |
| (unsigned long)objp); |
| BUG(); |
| } |
| } |
| |
| static inline void verify_redzone_free(struct kmem_cache *cache, void *obj) |
| { |
| unsigned long long redzone1, redzone2; |
| |
| redzone1 = *dbg_redzone1(cache, obj); |
| redzone2 = *dbg_redzone2(cache, obj); |
| |
| /* |
| * Redzone is ok. |
| */ |
| if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE) |
| return; |
| |
| if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE) |
| slab_error(cache, "double free detected"); |
| else |
| slab_error(cache, "memory outside object was overwritten"); |
| |
| printk(KERN_ERR "%p: redzone 1:0x%llx, redzone 2:0x%llx.\n", |
| obj, redzone1, redzone2); |
| } |
| |
| static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, |
| void *caller) |
| { |
| struct page *page; |
| unsigned int objnr; |
| struct slab *slabp; |
| |
| objp -= obj_offset(cachep); |
| kfree_debugcheck(objp); |
| page = virt_to_head_page(objp); |
| |
| slabp = page_get_slab(page); |
| |
| if (cachep->flags & SLAB_RED_ZONE) { |
| verify_redzone_free(cachep, objp); |
| *dbg_redzone1(cachep, objp) = RED_INACTIVE; |
| *dbg_redzone2(cachep, objp) = RED_INACTIVE; |
| } |
| if (cachep->flags & SLAB_STORE_USER) |
| *dbg_userword(cachep, objp) = caller; |
| |
| objnr = obj_to_index(cachep, slabp, objp); |
| |
| BUG_ON(objnr >= cachep->num); |
| BUG_ON(objp != index_to_obj(cachep, slabp, objnr)); |
| |
| #ifdef CONFIG_DEBUG_SLAB_LEAK |
| slab_bufctl(slabp)[objnr] = BUFCTL_FREE; |
| #endif |
| if (cachep->flags & SLAB_POISON) { |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| if ((cachep->buffer_size % PAGE_SIZE)==0 && OFF_SLAB(cachep)) { |
| store_stackinfo(cachep, objp, (unsigned long)caller); |
| kernel_map_pages(virt_to_page(objp), |
| cachep->buffer_size / PAGE_SIZE, 0); |
| } else { |
| poison_obj(cachep, objp, POISON_FREE); |
| } |
| #else |
| poison_obj(cachep, objp, POISON_FREE); |
| #endif |
| } |
| 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). Hexdump:\n", |
| cachep->name, cachep->num, slabp, slabp->inuse); |
| for (i = 0; |
| i < sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t); |
| i++) { |
| if (i % 16 == 0) |
| printk("\n%03x:", i); |
| printk(" %02x", ((unsigned char *)slabp)[i]); |
| } |
| printk("\n"); |
| 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) |
| { |
| int batchcount; |
| struct kmem_list3 *l3; |
| struct array_cache *ac; |
| int node; |
| |
| node = numa_node_id(); |
| |
| check_irq_off(); |
| ac = cpu_cache_get(cachep); |
| retry: |
| batchcount = ac->batchcount; |
| if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { |
| /* |
| * If there was little recent activity on this cache, then |
| * perform only a partial refill. Otherwise we could generate |
| * refill bouncing. |
| */ |
| batchcount = BATCHREFILL_LIMIT; |
| } |
| l3 = cachep->nodelists[node]; |
| |
| BUG_ON(ac->avail > 0 || !l3); |
| spin_lock(&l3->list_lock); |
| |
| /* See if we can refill from the shared array */ |
| if (l3->shared && transfer_objects(ac, l3->shared, batchcount)) |
| goto alloc_done; |
| |
| while (batchcount > 0) { |
| struct list_head *entry; |
| struct slab *slabp; |
| /* Get slab alloc is to come from. */ |
| entry = l3->slabs_partial.next; |
| if (entry == &l3->slabs_partial) { |
| l3->free_touched = 1; |
| entry = l3->slabs_free.next; |
| if (entry == &l3->slabs_free) |
| goto must_grow; |
| } |
| |
| slabp = list_entry(entry, struct slab, list); |
| check_slabp(cachep, slabp); |
| check_spinlock_acquired(cachep); |
| |
| /* |
| * The slab was either on partial or free list so |
| * there must be at least one object available for |
| * allocation. |
| */ |
| BUG_ON(slabp->inuse < 0 || slabp->inuse >= cachep->num); |
| |
| while (slabp->inuse < cachep->num && batchcount--) { |
| STATS_INC_ALLOCED(cachep); |
| STATS_INC_ACTIVE(cachep); |
| STATS_SET_HIGH(cachep); |
| |
| ac->entry[ac->avail++] = slab_get_obj(cachep, slabp, |
| node); |
| } |
| check_slabp(cachep, slabp); |
| |
| /* move slabp to correct slabp list: */ |
| list_del(&slabp->list); |
| if (slabp->free == BUFCTL_END) |
| list_add(&slabp->list, &l3->slabs_full); |
| else |
| list_add(&slabp->list, &l3->slabs_partial); |
| } |
| |
| must_grow: |
| l3->free_objects -= ac->avail; |
| alloc_done: |
| spin_unlock(&l3->list_lock); |
| |
| if (unlikely(!ac->avail)) { |
| int x; |
| x = cache_grow(cachep, flags | GFP_THISNODE, node, NULL); |
| |
| /* cache_grow can reenable interrupts, then ac could change. */ |
| ac = cpu_cache_get(cachep); |
| if (!x && ac->avail == 0) /* no objects in sight? abort */ |
| return NULL; |
| |
| if (!ac->avail) /* objects refilled by interrupt? */ |
| goto retry; |
| } |
| ac->touched = 1; |
| return ac->entry[--ac->avail]; |
| } |
| |
| static inline void cache_alloc_debugcheck_before(struct kmem_cache *cachep, |
| gfp_t flags) |
| { |
| might_sleep_if(flags & __GFP_WAIT); |
| #if DEBUG |
| kmem_flagcheck(cachep, flags); |
| #endif |
| } |
| |
| #if DEBUG |
| static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, |
| gfp_t flags, void *objp, void *caller) |
| { |
| if (!objp) |
| return objp; |
| if (cachep->flags & SLAB_POISON) { |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) |
| kernel_map_pages(virt_to_page(objp), |
| cachep->buffer_size / PAGE_SIZE, 1); |
| else |
| check_poison_obj(cachep, objp); |
| #else |
| check_poison_obj(cachep, objp); |
| #endif |
| poison_obj(cachep, objp, POISON_INUSE); |
| } |
| if (cachep->flags & SLAB_STORE_USER) |
| *dbg_userword(cachep, objp) = caller; |
| |
| if (cachep->flags & SLAB_RED_ZONE) { |
| if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || |
| *dbg_redzone2(cachep, objp) != RED_INACTIVE) { |
| slab_error(cachep, "double free, or memory outside" |
| " object was overwritten"); |
| printk(KERN_ERR |
| "%p: redzone 1:0x%llx, redzone 2:0x%llx\n", |
| objp, *dbg_redzone1(cachep, objp), |
| *dbg_redzone2(cachep, objp)); |
| } |
| *dbg_redzone1(cachep, objp) = RED_ACTIVE; |
| *dbg_redzone2(cachep, objp) = RED_ACTIVE; |
| } |
| #ifdef CONFIG_DEBUG_SLAB_LEAK |
| { |
| struct slab *slabp; |
| unsigned objnr; |
| |
| slabp = page_get_slab(virt_to_head_page(objp)); |
| objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size; |
| slab_bufctl(slabp)[objnr] = BUFCTL_ACTIVE; |
| } |
| #endif |
| objp += obj_offset(cachep); |
| if (cachep->ctor && cachep->flags & SLAB_POISON) |
| cachep->ctor(objp, cachep, 0); |
| #if ARCH_SLAB_MINALIGN |
| if ((u32)objp & (ARCH_SLAB_MINALIGN-1)) { |
| printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n", |
| objp, ARCH_SLAB_MINALIGN); |
| } |
| #endif |
| return objp; |
| } |
| #else |
| #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) |
| #endif |
| |
| #ifdef CONFIG_FAILSLAB |
| |
| static struct failslab_attr { |
| |
| struct fault_attr attr; |
| |
| u32 ignore_gfp_wait; |
| #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS |
| struct dentry *ignore_gfp_wait_file; |
| #endif |
| |
| } failslab = { |
| .attr = FAULT_ATTR_INITIALIZER, |
| .ignore_gfp_wait = 1, |
| }; |
| |
| static int __init setup_failslab(char *str) |
| { |
| return setup_fault_attr(&failslab.attr, str); |
| } |
| __setup("failslab=", setup_failslab); |
| |
| static int should_failslab(struct kmem_cache *cachep, gfp_t flags) |
| { |
| if (cachep == &cache_cache) |
| return 0; |
| if (flags & __GFP_NOFAIL) |
| return 0; |
| if (failslab.ignore_gfp_wait && (flags & __GFP_WAIT)) |
| return 0; |
| |
| return should_fail(&failslab.attr, obj_size(cachep)); |
| } |
| |
| #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS |
| |
| static int __init failslab_debugfs(void) |
| { |
| mode_t mode = S_IFREG | S_IRUSR | S_IWUSR; |
| struct dentry *dir; |
| int err; |
| |
| err = init_fault_attr_dentries(&failslab.attr, "failslab"); |
| if (err) |
| return err; |
| dir = failslab.attr.dentries.dir; |
| |
| failslab.ignore_gfp_wait_file = |
| debugfs_create_bool("ignore-gfp-wait", mode, dir, |
| &failslab.ignore_gfp_wait); |
| |
| if (!failslab.ignore_gfp_wait_file) { |
| err = -ENOMEM; |
| debugfs_remove(failslab.ignore_gfp_wait_file); |
| cleanup_fault_attr_dentries(&failslab.attr); |
| } |
| |
| return err; |
| } |
| |
| late_initcall(failslab_debugfs); |
| |
| #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ |
| |
| #else /* CONFIG_FAILSLAB */ |
| |
| static inline int should_failslab(struct kmem_cache *cachep, gfp_t flags) |
| { |
| return 0; |
| } |
| |
| #endif /* CONFIG_FAILSLAB */ |
| |
| static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
| { |
| void *objp; |
| struct array_cache *ac; |
| |
| check_irq_off(); |
| |
| ac = cpu_cache_get(cachep); |
| if (likely(ac->avail)) { |
| STATS_INC_ALLOCHIT(cachep); |
| ac->touched = 1; |
| objp = ac->entry[--ac->avail]; |
| } else { |
| STATS_INC_ALLOCMISS(cachep); |
| objp = cache_alloc_refill(cachep, flags); |
| } |
| return objp; |
| } |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * Try allocating on another node if PF_SPREAD_SLAB|PF_MEMPOLICY. |
| * |
| * If we are in_interrupt, then process context, including cpusets and |
| * mempolicy, may not apply and should not be used for allocation policy. |
| */ |
| static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) |
| { |
| int nid_alloc, nid_here; |
| |
| if (in_interrupt() || (flags & __GFP_THISNODE)) |
| return NULL; |
| nid_alloc = nid_here = numa_node_id(); |
| if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) |
| nid_alloc = cpuset_mem_spread_node(); |
| else if (current->mempolicy) |
| nid_alloc = slab_node(current->mempolicy); |
| if (nid_alloc != nid_here) |
| return ____cache_alloc_node(cachep, flags, nid_alloc); |
| return NULL; |
| } |
| |
| /* |
| * Fallback function if there was no memory available and no objects on a |
| * certain node and fall back is permitted. First we scan all the |
| * available nodelists for available objects. If that fails then we |
| * perform an allocation without specifying a node. This allows the page |
| * allocator to do its reclaim / fallback magic. We then insert the |
| * slab into the proper nodelist and then allocate from it. |
| */ |
| static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) |
| { |
| struct zonelist *zonelist; |
| gfp_t local_flags; |
| struct zone **z; |
| void *obj = NULL; |
| int nid; |
| |
| if (flags & __GFP_THISNODE) |
| return NULL; |
| |
| zonelist = &NODE_DATA(slab_node(current->mempolicy)) |
| ->node_zonelists[gfp_zone(flags)]; |
| local_flags = (flags & GFP_LEVEL_MASK); |
| |
| retry: |
| /* |
| * Look through allowed nodes for objects available |
| * from existing per node queues. |
| */ |
| for (z = zonelist->zones; *z && !obj; z++) { |
| nid = zone_to_nid(*z); |
| |
| if (cpuset_zone_allowed_hardwall(*z, flags) && |
| cache->nodelists[nid] && |
| cache->nodelists[nid]->free_objects) |
| obj = ____cache_alloc_node(cache, |
| flags | GFP_THISNODE, nid); |
| } |
| |
| if (!obj) { |
| /* |
| * This allocation will be performed within the constraints |
| * of the current cpuset / memory policy requirements. |
| * We may trigger various forms of reclaim on the allowed |
| * set and go into memory reserves if necessary. |
| */ |
| if (local_flags & __GFP_WAIT) |
| local_irq_enable(); |
| kmem_flagcheck(cache, flags); |
| obj = kmem_getpages(cache, flags, -1); |
| if (local_flags & __GFP_WAIT) |
| local_irq_disable(); |
| if (obj) { |
| /* |
| * Insert into the appropriate per node queues |
| */ |
| nid = page_to_nid(virt_to_page(obj)); |
| if (cache_grow(cache, flags, nid, obj)) { |
| obj = ____cache_alloc_node(cache, |
| flags | GFP_THISNODE, nid); |
| if (!obj) |
| /* |
| * Another processor may allocate the |
| * objects in the slab since we are |
| * not holding any locks. |
| */ |
| goto retry; |
| } else { |
| /* cache_grow already freed obj */ |
| obj = NULL; |
| } |
| } |
| } |
| return obj; |
| } |
| |
| /* |
| * A interface to enable slab creation on nodeid |
| */ |
| static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, |
| int nodeid) |
| { |
| struct list_head *entry; |
| struct slab *slabp; |
| struct kmem_list3 *l3; |
| void *obj; |
| int x; |
| |
| l3 = cachep->nodelists[nodeid]; |
| BUG_ON(!l3); |
| |
| retry: |
| check_irq_off(); |
| spin_lock(&l3->list_lock); |
| entry = l3->slabs_partial.next; |
| if (entry == &l3->slabs_partial) { |
| l3->free_touched = 1; |
| entry = l3->slabs_free.next; |
| if (entry == &l3->slabs_free) |
| goto must_grow; |
| } |
| |
| slabp = list_entry(entry, struct slab, list); |
| 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); |
| |
| obj = slab_get_obj(cachep, slabp, nodeid); |
| check_slabp(cachep, slabp); |
| l3->free_objects--; |
| /* move slabp to correct slabp list: */ |
| list_del(&slabp->list); |
| |
| if (slabp->free == BUFCTL_END) |
| list_add(&slabp->list, &l3->slabs_full); |
| else |
| list_add(&slabp->list, &l3->slabs_partial); |
| |
| spin_unlock(&l3->list_lock); |
| goto done; |
| |
| must_grow: |
| spin_unlock(&l3->list_lock); |
| x = cache_grow(cachep, flags | GFP_THISNODE, nodeid, NULL); |
| if (x) |
| goto retry; |
| |
| return fallback_alloc(cachep, flags); |
| |
| done: |
| return obj; |
| } |
| |
| /** |
| * kmem_cache_alloc_node - Allocate an object on the specified node |
| * @cachep: The cache to allocate from. |
| * @flags: See kmalloc(). |
| * @nodeid: node number of the target node. |
| * @caller: return address of caller, used for debug information |
| * |
| * Identical to kmem_cache_alloc but it will allocate memory on the given |
| * node, which can improve the performance for cpu bound structures. |
| * |
| * Fallback to other node is possible if __GFP_THISNODE is not set. |
| */ |
| static __always_inline void * |
| __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, |
| void *caller) |
| { |
| unsigned long save_flags; |
| void *ptr; |
| |
| if (should_failslab(cachep, flags)) |
| return NULL; |
| |
| cache_alloc_debugcheck_before(cachep, flags); |
| local_irq_save(save_flags); |
| |
| if (unlikely(nodeid == -1)) |
| nodeid = numa_node_id(); |
| |
| if (unlikely(!cachep->nodelists[nodeid])) { |
| /* Node not bootstrapped yet */ |
| ptr = fallback_alloc(cachep, flags); |
| goto out; |
| } |
| |
| if (nodeid == numa_node_id()) { |
| /* |
| * Use the locally cached objects if possible. |
| * However ____cache_alloc does not allow fallback |
| * to other nodes. It may fail while we still have |
| * objects on other nodes available. |
| */ |
| ptr = ____cache_alloc(cachep, flags); |
| if (ptr) |
| goto out; |
| } |
| /* ___cache_alloc_node can fall back to other nodes */ |
| ptr = ____cache_alloc_node(cachep, flags, nodeid); |
| out: |
| local_irq_restore(save_flags); |
| ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, caller); |
| |
| return ptr; |
| } |
| |
| static __always_inline void * |
| __do_cache_alloc(struct kmem_cache *cache, gfp_t flags) |
| { |
| void *objp; |
| |
| if (unlikely(current->flags & (PF_SPREAD_SLAB | PF_MEMPOLICY))) { |
| objp = alternate_node_alloc(cache, flags); |
| if (objp) |
| goto out; |
| } |
| objp = ____cache_alloc(cache, flags); |
| |
| /* |
| * We may just have run out of memory on the local node. |
| * ____cache_alloc_node() knows how to locate memory on other nodes |
| */ |
| if (!objp) |
| objp = ____cache_alloc_node(cache, flags, numa_node_id()); |
| |
| out: |
| return objp; |
| } |
| #else |
| |
| static __always_inline void * |
| __do_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
| { |
| return ____cache_alloc(cachep, flags); |
| } |
| |
| #endif /* CONFIG_NUMA */ |
| |
| static __always_inline void * |
| __cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller) |
| { |
| unsigned long save_flags; |
| void *objp; |
| |
| if (should_failslab(cachep, flags)) |
| return NULL; |
| |
| cache_alloc_debugcheck_before(cachep, flags); |
| local_irq_save(save_flags); |
| objp = __do_cache_alloc(cachep, flags); |
| local_irq_restore(save_flags); |
| objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); |
| prefetchw(objp); |
| |
| return objp; |
| } |
| |
| /* |
| * Caller needs to acquire correct kmem_list's list_lock |
| */ |
| static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects, |
| int node) |
| { |
| int i; |
| struct kmem_list3 *l3; |
| |
| for (i = 0; i < nr_objects; i++) { |
| void *objp = objpp[i]; |
| struct slab *slabp; |
| |
| slabp = virt_to_slab(objp); |
| l3 = cachep->nodelists[node]; |
| list_del(&slabp->list); |
| check_spinlock_acquired_node(cachep, node); |
| check_slabp(cachep, slabp); |
| slab_put_obj(cachep, slabp, objp, node); |
| STATS_DEC_ACTIVE(cachep); |
| l3->free_objects++; |
| check_slabp(cachep, slabp); |
| |
| /* fixup slab chains */ |
| if (slabp->inuse == 0) { |
| if (l3->free_objects > l3->free_limit) { |
| l3->free_objects -= cachep->num; |
| /* No need to drop any previously held |
| * lock here, even if we have a off-slab slab |
| * descriptor it is guaranteed to come from |
| * a different cache, refer to comments before |
| * alloc_slabmgmt. |
| */ |
| slab_destroy(cachep, slabp); |
| } else { |
| list_add(&slabp->list, &l3->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, &l3->slabs_partial); |
| } |
| } |
| } |
| |
| static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) |
| { |
| int batchcount; |
| struct kmem_list3 *l3; |
| int node = numa_node_id(); |
| |
| batchcount = ac->batchcount; |
| #if DEBUG |
| BUG_ON(!batchcount || batchcount > ac->avail); |
| #endif |
| check_irq_off(); |
| l3 = cachep->nodelists[node]; |
| spin_lock(&l3->list_lock); |
| if (l3->shared) { |
| struct array_cache *shared_array = l3->shared; |
| int max = shared_array->limit - shared_array->avail; |
| if (max) { |
| if (batchcount > max) |
| batchcount = max; |
| memcpy(&(shared_array->entry[shared_array->avail]), |
| ac->entry, sizeof(void *) * batchcount); |
| shared_array->avail += batchcount; |
| goto free_done; |
| } |
| } |
| |
| free_block(cachep, ac->entry, batchcount, node); |
| free_done: |
| #if STATS |
| { |
| int i = 0; |
| struct list_head *p; |
| |
| p = l3->slabs_free.next; |
| while (p != &(l3->slabs_free)) { |
| struct slab *slabp; |
| |
| slabp = list_entry(p, struct slab, list); |
| BUG_ON(slabp->inuse); |
| |
| i++; |
| p = p->next; |
| } |
| STATS_SET_FREEABLE(cachep, i); |
| } |
| #endif |
| spin_unlock(&l3->list_lock); |
| ac->avail -= batchcount; |
| memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); |
| } |
| |
| /* |
| * Release an obj back to its cache. If the obj has a constructed state, it must |
| * be in this state _before_ it is released. Called with disabled ints. |
| */ |
| static inline void __cache_free(struct kmem_cache *cachep, void *objp) |
| { |
| struct array_cache *ac = cpu_cache_get(cachep); |
| |
| check_irq_off(); |
| objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0)); |
| |
| if (cache_free_alien(cachep, objp)) |
| return; |
| |
| if (likely(ac->avail < ac->limit)) { |
| STATS_INC_FREEHIT(cachep); |
| ac->entry[ac->avail++] = objp; |
| return; |
| } else { |
| STATS_INC_FREEMISS(cachep); |
| cache_flusharray(cachep, ac); |
| ac->entry[ac->avail++] = objp; |
| } |
| } |
| |
| /** |
| * kmem_cache_alloc - Allocate an object |
| * @cachep: The cache to allocate from. |
| * @flags: See kmalloc(). |
| * |
| * Allocate an object from this cache. The flags are only relevant |
| * if the cache has no available objects. |
| */ |
| void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
| { |
| return __cache_alloc(cachep, flags, __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(kmem_cache_alloc); |
| |
| /** |
| * kmem_cache_zalloc - Allocate an object. The memory is set to zero. |
| * @cache: The cache to allocate from. |
| * @flags: See kmalloc(). |
| * |
| * Allocate an object from this cache and set the allocated memory to zero. |
| * The flags are only relevant if the cache has no available objects. |
| */ |
| void *kmem_cache_zalloc(struct kmem_cache *cache, gfp_t flags) |
| { |
| void *ret = __cache_alloc(cache, flags, __builtin_return_address(0)); |
| if (ret) |
| memset(ret, 0, obj_size(cache)); |
| return ret; |
| } |
| EXPORT_SYMBOL(kmem_cache_zalloc); |
| |
| /** |
| * kmem_ptr_validate - check if an untrusted pointer might |
| * be a slab entry. |
| * @cachep: the cache we're checking against |
| * @ptr: pointer to validate |
| * |
| * This verifies that the untrusted pointer looks sane: |
| * it is _not_ a guarantee that the pointer is actually |
| * part of the slab cache in question, but it at least |
| * validates that the pointer can be dereferenced and |
| * looks half-way sane. |
| * |
| * Currently only used for dentry validation. |
| */ |
| int kmem_ptr_validate(struct kmem_cache *cachep, const void *ptr) |
| { |
| unsigned long addr = (unsigned long)ptr; |
| unsigned long min_addr = PAGE_OFFSET; |
| unsigned long align_mask = BYTES_PER_WORD - 1; |
| unsigned long size = cachep->buffer_size; |
| struct page *page; |
| |
| if (unlikely(addr < min_addr)) |
| goto out; |
| if (unlikely(addr > (unsigned long)high_memory - size)) |
| goto out; |
| if (unlikely(addr & align_mask)) |
| goto out; |
| if (unlikely(!kern_addr_valid(addr))) |
| goto out; |
| if (unlikely(!kern_addr_valid(addr + size - 1))) |
| goto out; |
| page = virt_to_page(ptr); |
| if (unlikely(!PageSlab(page))) |
| goto out; |
| if (unlikely(page_get_cache(page) != cachep)) |
| goto out; |
| return 1; |
| out: |
| return 0; |
| } |
| |
| #ifdef CONFIG_NUMA |
| void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
| { |
| return __cache_alloc_node(cachep, flags, nodeid, |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(kmem_cache_alloc_node); |
| |
| static __always_inline void * |
| __do_kmalloc_node(size_t size, gfp_t flags, int node, void *caller) |
| { |
| struct kmem_cache *cachep; |
| |
| cachep = kmem_find_general_cachep(size, flags); |
| if (unlikely(ZERO_OR_NULL_PTR(cachep))) |
| return cachep; |
| return kmem_cache_alloc_node(cachep, flags, node); |
| } |
| |
| #ifdef CONFIG_DEBUG_SLAB |
| void *__kmalloc_node(size_t size, gfp_t flags, int node) |
| { |
| return __do_kmalloc_node(size, flags, node, |
| __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(__kmalloc_node); |
| |
| void *__kmalloc_node_track_caller(size_t size, gfp_t flags, |
| int node, void *caller) |
| { |
| return __do_kmalloc_node(size, flags, node, caller); |
| } |
| EXPORT_SYMBOL(__kmalloc_node_track_caller); |
| #else |
| void *__kmalloc_node(size_t size, gfp_t flags, int node) |
| { |
| return __do_kmalloc_node(size, flags, node, NULL); |
| } |
| EXPORT_SYMBOL(__kmalloc_node); |
| #endif /* CONFIG_DEBUG_SLAB */ |
| #endif /* CONFIG_NUMA */ |
| |
| /** |
| * __do_kmalloc - allocate memory |
| * @size: how many bytes of memory are required. |
| * @flags: the type of memory to allocate (see kmalloc). |
| * @caller: function caller for debug tracking of the caller |
| */ |
| static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, |
| void *caller) |
| { |
| struct kmem_cache *cachep; |
| |
| /* If you want to save a few bytes .text space: replace |
| * __ with kmem_. |
| * Then kmalloc uses the uninlined functions instead of the inline |
| * functions. |
| */ |
| cachep = __find_general_cachep(size, flags); |
| if (unlikely(cachep == NULL)) |
| return NULL; |
| return __cache_alloc(cachep, flags, caller); |
| } |
| |
| |
| #ifdef CONFIG_DEBUG_SLAB |
| void *__kmalloc(size_t size, gfp_t flags) |
| { |
| return __do_kmalloc(size, flags, __builtin_return_address(0)); |
| } |
| EXPORT_SYMBOL(__kmalloc); |
| |
| void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller) |
| { |
| return __do_kmalloc(size, flags, caller); |
| } |
| EXPORT_SYMBOL(__kmalloc_track_caller); |
| |
| #else |
| void *__kmalloc(size_t size, gfp_t flags) |
| { |
| return __do_kmalloc(size, flags, NULL); |
| } |
| EXPORT_SYMBOL(__kmalloc); |
| #endif |
| |
| /** |
| * kmem_cache_free - Deallocate an object |
| * @cachep: The cache the allocation was from. |
| * @objp: The previously allocated object. |
| * |
| * Free an object which was previously allocated from this |
| * cache. |
| */ |
| void kmem_cache_free(struct kmem_cache *cachep, void *objp) |
| { |
| unsigned long flags; |
| |
| BUG_ON(virt_to_cache(objp) != cachep); |
| |
| local_irq_save(flags); |
| debug_check_no_locks_freed(objp, obj_size(cachep)); |
| __cache_free(cachep, objp); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL(kmem_cache_free); |
| |
| /** |
| * kfree - free previously allocated memory |
| * @objp: pointer returned by kmalloc. |
| * |
| * If @objp is NULL, no operation is performed. |
| * |
| * Don't free memory not originally allocated by kmalloc() |
| * or you will run into trouble. |
| */ |
| void kfree(const void *objp) |
| { |
| struct kmem_cache *c; |
| unsigned long flags; |
| |
| if (unlikely(ZERO_OR_NULL_PTR(objp))) |
| return; |
| local_irq_save(flags); |
| kfree_debugcheck(objp); |
| c = virt_to_cache(objp); |
| debug_check_no_locks_freed(objp, obj_size(c)); |
| __cache_free(c, (void *)objp); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL(kfree); |
| |
| unsigned int kmem_cache_size(struct kmem_cache *cachep) |
| { |
| return obj_size(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 varioius caches for all nodes. |
| */ |
| static int alloc_kmemlist(struct kmem_cache *cachep) |
| { |
| int node; |
| struct kmem_list3 *l3; |
| struct array_cache *new_shared; |
| struct array_cache **new_alien = NULL; |
| |
| for_each_online_node(node) { |
| |
| if (use_alien_caches) { |
| new_alien = alloc_alien_cache(node, cachep->limit); |
| if (!new_alien) |
| goto fail; |
| } |
| |
| new_shared = NULL; |
| if (cachep->shared) { |
| new_shared = alloc_arraycache(node, |
| cachep->shared*cachep->batchcount, |
| 0xbaadf00d); |
| if (!new_shared) { |
| free_alien_cache(new_alien); |
| goto fail; |
| } |
| } |
| |
| l3 = cachep->nodelists[node]; |
| if (l3) { |
| struct array_cache *shared = l3->shared; |
| |
| spin_lock_irq(&l3->list_lock); |
| |
| if (shared) |
| free_block(cachep, shared->entry, |
| shared->avail, node); |
| |
| l3->shared = new_shared; |
| if (!l3->alien) { |
| l3->alien = new_alien; |
| new_alien = NULL; |
| } |
| l3->free_limit = (1 + nr_cpus_node(node)) * |
| cachep->batchcount + cachep->num; |
| spin_unlock_irq(&l3->list_lock); |
| kfree(shared); |
| free_alien_cache(new_alien); |
| continue; |
| } |
| l3 = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, node); |
| if (!l3) { |
| free_alien_cache(new_alien); |
| kfree(new_shared); |
| goto fail; |
| } |
| |
| kmem_list3_init(l3); |
| l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + |
| ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
| l3->shared = new_shared; |
| l3->alien = new_alien; |
| l3->free_limit = (1 + nr_cpus_node(node)) * |
| cachep->batchcount + cachep->num; |
| cachep->nodelists[node] = l3; |
| } |
| return 0; |
| |
| fail: |
| if (!cachep->next.next) { |
| /* Cache is not active yet. Roll back what we did */ |
| node--; |
| while (node >= 0) { |
| if (cachep->nodelists[node]) { |
| l3 = cachep->nodelists[node]; |
| |
| kfree(l3->shared); |
| free_alien_cache(l3->alien); |
| kfree(l3); |
| cachep->nodelists[node] = NULL; |
| } |
| node--; |
| } |
| } |
| return -ENOMEM; |
| } |
| |
| struct ccupdate_struct { |
| struct kmem_cache *cachep; |
| struct array_cache *new[NR_CPUS]; |
| }; |
| |
| static void do_ccupdate_local(void *info) |
| { |
| struct ccupdate_struct *new = info; |
| struct array_cache *old; |
| |
| check_irq_off(); |
| old = cpu_cache_get(new->cachep); |
| |
| new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; |
| new->new[smp_processor_id()] = old; |
| } |
| |
| /* Always called with the cache_chain_mutex held */ |
| static int do_tune_cpucache(struct kmem_cache *cachep, int limit, |
| int batchcount, int shared) |
| { |
| struct ccupdate_struct *new; |
| int i; |
| |
| new = kzalloc(sizeof(*new), GFP_KERNEL); |
| if (!new) |
| return -ENOMEM; |
| |
| for_each_online_cpu(i) { |
| new->new[i] = alloc_arraycache(cpu_to_node(i), limit, |
| batchcount); |
| if (!new->new[i]) { |
| for (i--; i >= 0; i--) |
| kfree(new->new[i]); |
| kfree(new); |
| return -ENOMEM; |
| } |
| } |
| new->cachep = cachep; |
| |
| on_each_cpu(do_ccupdate_local, (void *)new, 1, 1); |
| |
| check_irq_on(); |
| cachep->batchcount = batchcount; |
| cachep->limit = limit; |
| cachep->shared = shared; |
| |
| for_each_online_cpu(i) { |
| struct array_cache *ccold = new->new[i]; |
| if (!ccold) |
| continue; |
| spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
| free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i)); |
| spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
| kfree(ccold); |
| } |
| kfree(new); |
| return alloc_kmemlist(cachep); |
| } |
| |
| /* Called with cache_chain_mutex held always */ |
| static int enable_cpucache(struct kmem_cache *cachep) |
| { |
| int err; |
| int limit, shared; |
| |
| /* |
| * The head array serves three purposes: |
| * - create a LIFO ordering, i.e. return objects that are cache-warm |
| * - reduce the number of spinlock operations. |
| * - reduce the number of linked list operations on the slab and |
| * bufctl chains: array operations are cheaper. |
| * The numbers are guessed, we should auto-tune as described by |
| * Bonwick. |
| */ |
| if (cachep->buffer_size > 131072) |
| limit = 1; |
| else if (cachep->buffer_size > PAGE_SIZE) |
| limit = 8; |
| else if (cachep->buffer_size > 1024) |
| limit = 24; |
| else if (cachep->buffer_size > 256) |
| limit = 54; |
| else |
| limit = 120; |
| |
| /* |
| * CPU bound tasks (e.g. network routing) can exhibit cpu bound |
| * allocation behaviour: Most allocs on one cpu, most free operations |
| * on another cpu. For these cases, an efficient object passing between |
| * cpus is necessary. This is provided by a shared array. The array |
| * replaces Bonwick's magazine layer. |
| * On uniprocessor, it's functionally equivalent (but less efficient) |
| * to a larger limit. Thus disabled by default. |
| */ |
| shared = 0; |
| if (cachep->buffer_size <= PAGE_SIZE && num_possible_cpus() > 1) |
| shared = 8; |
| |
| #if DEBUG |
| /* |
| * With debugging enabled, large batchcount lead to excessively long |
| * periods with disabled local interrupts. Limit the batchcount |
| */ |
| if (limit > 32) |
| limit = 32; |
| #endif |
| err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared); |
| if (err) |
| printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n", |
| cachep->name, -err); |
| return err; |
| } |
| |
| /* |
| * Drain an array if it contains any elements taking the l3 lock only if |
| * necessary. Note that the l3 listlock also protects the array_cache |
| * if drain_array() is used on the shared array. |
| */ |
| void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, |
| struct array_cache *ac, int force, int node) |
| { |
| int tofree; |
| |
| if (!ac || !ac->avail) |
| return; |
| if (ac->touched && !force) { |
| ac->touched = 0; |
| } else { |
| spin_lock_irq(&l3->list_lock); |
| if (ac->avail) { |
| tofree = force ? ac->avail : (ac->limit + 4) / 5; |
| if (tofree > ac->avail) |
| tofree = (ac->avail + 1) / 2; |
| free_block(cachep, ac->entry, tofree, node); |
| ac->avail -= tofree; |
| memmove(ac->entry, &(ac->entry[tofree]), |
| sizeof(void *) * ac->avail); |
| } |
| spin_unlock_irq(&l3->list_lock); |
| } |
| } |
| |
| /** |
| * cache_reap - Reclaim memory from caches. |
| * @w: work descriptor |
| * |
| * Called from workqueue/eventd every few seconds. |
| * Purpose: |
| * - clear the per-cpu caches for this CPU. |
| * - return freeable pages to the main free memory pool. |
| * |
| * If we cannot acquire the cache chain mutex then just give up - we'll try |
| * again on the next iteration. |
| */ |
| static void cache_reap(struct work_struct *w) |
| { |
| struct kmem_cache *searchp; |
| struct kmem_list3 *l3; |
| int node = numa_node_id(); |
| struct delayed_work *work = |
| container_of(w, struct delayed_work, work); |
| |
| if (!mutex_trylock(&cache_chain_mutex)) |
| /* Give up. Setup the next iteration. */ |
| goto out; |
| |
| list_for_each_entry(searchp, &cache_chain, next) { |
| check_irq_on(); |
| |
| /* |
| * We only take the l3 lock if absolutely necessary and we |
| * have established with reasonable certainty that |
| * we can do some work if the lock was obtained. |
| */ |
| l3 = searchp->nodelists[node]; |
| |
| reap_alien(searchp, l3); |
| |
| drain_array(searchp, l3, cpu_cache_get(searchp), 0, node); |
| |
| /* |
| * These are racy checks but it does not matter |
| * if we skip one check or scan twice. |
| */ |
| if (time_after(l3->next_reap, jiffies)) |
| goto next; |
| |
| l3->next_reap = jiffies + REAPTIMEOUT_LIST3; |
| |
| drain_array(searchp, l3, l3->shared, 0, node); |
| |
| if (l3->free_touched) |
| l3->free_touched = 0; |
| else { |
| int freed; |
| |
| freed = drain_freelist(searchp, l3, (l3->free_limit + |
| 5 * searchp->num - 1) / (5 * searchp->num)); |
| STATS_ADD_REAPED(searchp, freed); |
| } |
| next: |
| cond_resched(); |
| } |
| check_irq_on(); |
| mutex_unlock(&cache_chain_mutex); |
| next_reap_node(); |
| out: |
| /* Set up the next iteration */ |
| schedule_delayed_work(work, round_jiffies_relative(REAPTIMEOUT_CPUC)); |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| |
| static void print_slabinfo_header(struct seq_file *m) |
| { |
| /* |
| * Output format version, so at least we can change it |
| * without _too_ many complaints. |
| */ |
| #if STATS |
| seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); |
| #else |
| seq_puts(m, "slabinfo - version: 2.1\n"); |
| #endif |
| seq_puts(m, "# name <active_objs> <num_objs> <objsize> " |
| "<objperslab> <pagesperslab>"); |
| seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); |
| seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); |
| #if STATS |
| seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> " |
| "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>"); |
| seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); |
| #endif |
| seq_putc(m, '\n'); |
| } |
| |
| static void *s_start(struct seq_file *m, loff_t *pos) |
| { |
| loff_t n = *pos; |
| |
| mutex_lock(&cache_chain_mutex); |
| if (!n) |
| print_slabinfo_header(m); |
| |
| return seq_list_start(&cache_chain, *pos); |
| } |
| |
| static void *s_next(struct seq_file *m, void *p, loff_t *pos) |
| { |
| return seq_list_next(p, &cache_chain, pos); |
| } |
| |
| static void s_stop(struct seq_file *m, void *p) |
| { |
| mutex_unlock(&cache_chain_mutex); |
| } |
| |
| static int s_show(struct seq_file *m, void *p) |
| { |
| struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next); |
| struct slab *slabp; |
| unsigned long active_objs; |
| unsigned long num_objs; |
| unsigned long active_slabs = 0; |
| unsigned long num_slabs, free_objects = 0, shared_avail = 0; |
| const char *name; |
| char *error = NULL; |
| int node; |
| struct kmem_list3 *l3; |
| |
| active_objs = 0; |
| num_slabs = 0; |
| for_each_online_node(node) { |
| l3 = cachep->nodelists[node]; |
| if (!l3) |
| continue; |
| |
| check_irq_on(); |
| spin_lock_irq(&l3->list_lock); |
| |
| list_for_each_entry(slabp, &l3->slabs_full, list) { |
| if (slabp->inuse != cachep->num && !error) |
| error = "slabs_full accounting error"; |
| active_objs += cachep->num; |
| active_slabs++; |
| } |
| list_for_each_entry(slabp, &l3->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; |
| active_slabs++; |
| } |
| list_for_each_entry(slabp, &l3->slabs_free, list) { |
| if (slabp->inuse && !error) |
| error = "slabs_free/inuse accounting error"; |
| num_slabs++; |
| } |
| free_objects += l3->free_objects; |
| if (l3->shared) |
| shared_avail += l3->shared->avail; |
| |
| spin_unlock_irq(&l3->list_lock); |
| } |
| num_slabs += active_slabs; |
| num_objs = num_slabs * cachep->num; |
| if (num_objs - active_objs != free_objects && !error) |
| error = "free_objects accounting error"; |
| |
| name = cachep->name; |
| if (error) |
| printk(KERN_ERR "slab: cache %s error: %s\n", name, error); |
| |
| seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", |
| name, active_objs, num_objs, cachep->buffer_size, |
| cachep->num, (1 << cachep->gfporder)); |
| seq_printf(m, " : tunables %4u %4u %4u", |
| cachep->limit, cachep->batchcount, cachep->shared); |
| seq_printf(m, " : slabdata %6lu %6lu %6lu", |
| active_slabs, num_slabs, shared_avail); |
| #if STATS |
| { /* list3 stats */ |
| unsigned long high = cachep->high_mark; |
| unsigned long allocs = cachep->num_allocations; |
| unsigned long grown = cachep->grown; |
| unsigned long reaped = cachep->reaped; |
| unsigned long errors = cachep->errors; |
| unsigned long max_freeable = cachep->max_freeable; |
| unsigned long node_allocs = cachep->node_allocs; |
| unsigned long node_frees = cachep->node_frees; |
| unsigned long overflows = cachep->node_overflow; |
| |
| seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \ |
| %4lu %4lu %4lu %4lu %4lu", allocs, high, grown, |
| reaped, errors, max_freeable, node_allocs, |
| node_frees, overflows); |
| } |
| /* cpu stats */ |
| { |
| unsigned long allochit = atomic_read(&cachep->allochit); |
| unsigned long allocmiss = atomic_read(&cachep->allocmiss); |
| unsigned long freehit = atomic_read(&cachep->freehit); |
| unsigned long freemiss = atomic_read(&cachep->freemiss); |
| |
| seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", |
| allochit, allocmiss, freehit, freemiss); |
| } |
| #endif |
| seq_putc(m, '\n'); |
| return 0; |
| } |
| |
| /* |
| * slabinfo_op - iterator that generates /proc/slabinfo |
| * |
| * Output layout: |
| * cache-name |
| * num-active-objs |
| * total-objs |
| * object size |
| * num-active-slabs |
| * total-slabs |
| * num-pages-per-slab |
| * + further values on SMP and with statistics enabled |
| */ |
| |
| const struct seq_operations slabinfo_op = { |
| .start = s_start, |
| .next = s_next, |
| .stop = s_stop, |
| .show = s_show, |
| }; |
| |
| #define MAX_SLABINFO_WRITE 128 |
| /** |
| * slabinfo_write - Tuning for the slab allocator |
| * @file: unused |
| * @buffer: user buffer |
| * @count: data length |
| * @ppos: unused |
| */ |
| ssize_t slabinfo_write(struct file *file, const char __user * buffer, |
| size_t count, loff_t *ppos) |
| { |
| char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; |
| int limit, batchcount, shared, res; |
| struct kmem_cache *cachep; |
| |
| if (count > MAX_SLABINFO_WRITE) |
| return -EINVAL; |
| if (copy_from_user(&kbuf, buffer, count)) |
| return -EFAULT; |
| kbuf[MAX_SLABINFO_WRITE] = '\0'; |
| |
| tmp = strchr(kbuf, ' '); |
| if (!tmp) |
| return -EINVAL; |
| *tmp = '\0'; |
| tmp++; |
| if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) |
| return -EINVAL; |
| |
| /* Find the cache in the chain of caches. */ |
| mutex_lock(&cache_chain_mutex); |
| res = -EINVAL; |
| list_for_each_entry(cachep, &cache_chain, next) { |
| if (!strcmp(cachep->name, kbuf)) { |
| if (limit < 1 || batchcount < 1 || |
| batchcount > limit || shared < 0) { |
| res = 0; |
| } else { |
| res = do_tune_cpucache(cachep, limit, |
| batchcount, shared); |
| } |
| break; |
| } |
| } |
| mutex_unlock(&cache_chain_mutex); |
| if (res >= 0) |
| res = count; |
| return res; |
| } |
| |
| #ifdef CONFIG_DEBUG_SLAB_LEAK |
| |
| static void *leaks_start(struct seq_file *m, loff_t *pos) |
| { |
| mutex_lock(&cache_chain_mutex); |
| return seq_list_start(&cache_chain, *pos); |
| } |
| |
| static inline int add_caller(unsigned long *n, unsigned long v) |
| { |
| unsigned long *p; |
| int l; |
| if (!v) |
| return 1; |
| l = n[1]; |
| p = n + 2; |
| while (l) { |
| int i = l/2; |
| unsigned long *q = p + 2 * i; |
| if (*q == v) { |
| q[1]++; |
| return 1; |
| } |
| if (*q > v) { |
| l = i; |
| } else { |
| p = q + 2; |
| l -= i + 1; |
| } |
| } |
| if (++n[1] == n[0]) |
| return 0; |
| memmove(p + 2, p, n[1] * 2 * sizeof(unsigned long) - ((void *)p - (void *)n)); |
| p[0] = v; |
| p[1] = 1; |
| return 1; |
| } |
| |
| static void handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s) |
| { |
| void *p; |
| int i; |
| if (n[0] == n[1]) |
| return; |
| for (i = 0, p = s->s_mem; i < c->num; i++, p += c->buffer_size) { |
| if (slab_bufctl(s)[i] != BUFCTL_ACTIVE) |
| continue; |
| if (!add_caller(n, (unsigned long)*dbg_userword(c, p))) |
| return; |
| } |
| } |
| |
| static void show_symbol(struct seq_file *m, unsigned long address) |
| { |
| #ifdef CONFIG_KALLSYMS |
| unsigned long offset, size; |
| char modname[MODULE_NAME_LEN + 1], name[KSYM_NAME_LEN + 1]; |
| |
| if (lookup_symbol_attrs(address, &size, &offset, modname, name) == 0) { |
| seq_printf(m, "%s+%#lx/%#lx", name, offset, size); |
| if (modname[0]) |
| seq_printf(m, " [%s]", modname); |
| return; |
| } |
| #endif |
| seq_printf(m, "%p", (void *)address); |
| } |
| |
| static int leaks_show(struct seq_file *m, void *p) |
| { |
| struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next); |
| struct slab *slabp; |
| struct kmem_list3 *l3; |
| const char *name; |
| unsigned long *n = m->private; |
| int node; |
| int i; |
| |
| if (!(cachep->flags & SLAB_STORE_USER)) |
| return 0; |
| if (!(cachep->flags & SLAB_RED_ZONE)) |
| return 0; |
| |
| /* OK, we can do it */ |
| |
| n[1] = 0; |
| |
| for_each_online_node(node) { |
| l3 = cachep->nodelists[node]; |
| if (!l3) |
| continue; |
| |
| check_irq_on(); |
| spin_lock_irq(&l3->list_lock); |
| |
| list_for_each_entry(slabp, &l3->slabs_full, list) |
| handle_slab(n, cachep, slabp); |
| list_for_each_entry(slabp, &l3->slabs_partial, list) |
| handle_slab(n, cachep, slabp); |
| spin_unlock_irq(&l3->list_lock); |
| } |
| name = cachep->name; |
| if (n[0] == n[1]) { |
| /* Increase the buffer size */ |
| mutex_unlock(&cache_chain_mutex); |
| m->private = kzalloc(n[0] * 4 * sizeof(unsigned long), GFP_KERNEL); |
| if (!m->private) { |
| /* Too bad, we are really out */ |
| m->private = n; |
| mutex_lock(&cache_chain_mutex); |
| return -ENOMEM; |
| } |
| *(unsigned long *)m->private = n[0] * 2; |
| kfree(n); |
| mutex_lock(&cache_chain_mutex); |
| /* Now make sure this entry will be retried */ |
| m->count = m->size; |
| return 0; |
| } |
| for (i = 0; i < n[1]; i++) { |
| seq_printf(m, "%s: %lu ", name, n[2*i+3]); |
| show_symbol(m, n[2*i+2]); |
| seq_putc(m, '\n'); |
| } |
| |
| return 0; |
| } |
| |
| const struct seq_operations slabstats_op = { |
| .start = leaks_start, |
| .next = s_next, |
| .stop = s_stop, |
| .show = leaks_show, |
| }; |
| #endif |
| #endif |
| |
| /** |
| * ksize - get the actual amount of memory allocated for a given object |
| * @objp: Pointer to the object |
| * |
| * kmalloc may internally round up allocations and return more memory |
| * than requested. ksize() can be used to determine the actual amount of |
| * memory allocated. The caller may use this additional memory, even though |
| * a smaller amount of memory was initially specified with the kmalloc call. |
| * The caller must guarantee that objp points to a valid object previously |
| * allocated with either kmalloc() or kmem_cache_alloc(). The object |
| * must not be freed during the duration of the call. |
| */ |
| size_t ksize(const void *objp) |
| { |
| if (unlikely(ZERO_OR_NULL_PTR(objp))) |
| return 0; |
| |
| return obj_size(virt_to_cache(objp)); |
| } |