| /* |
| * SLUB: A slab allocator that limits cache line use instead of queuing |
| * objects in per cpu and per node lists. |
| * |
| * The allocator synchronizes using per slab locks and only |
| * uses a centralized lock to manage a pool of partial slabs. |
| * |
| * (C) 2007 SGI, Christoph Lameter <clameter@sgi.com> |
| */ |
| |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/bit_spinlock.h> |
| #include <linux/interrupt.h> |
| #include <linux/bitops.h> |
| #include <linux/slab.h> |
| #include <linux/seq_file.h> |
| #include <linux/cpu.h> |
| #include <linux/cpuset.h> |
| #include <linux/mempolicy.h> |
| #include <linux/ctype.h> |
| #include <linux/kallsyms.h> |
| |
| /* |
| * Lock order: |
| * 1. slab_lock(page) |
| * 2. slab->list_lock |
| * |
| * The slab_lock protects operations on the object of a particular |
| * slab and its metadata in the page struct. If the slab lock |
| * has been taken then no allocations nor frees can be performed |
| * on the objects in the slab nor can the slab be added or removed |
| * from the partial or full lists since this would mean modifying |
| * the page_struct of the slab. |
| * |
| * The list_lock protects the partial and full list on each node and |
| * the partial slab counter. If taken then no new slabs may be added or |
| * removed from the lists nor make the number of partial slabs be modified. |
| * (Note that the total number of slabs is an atomic value that may be |
| * modified without taking the list lock). |
| * |
| * The list_lock is a centralized lock and thus we avoid taking it as |
| * much as possible. As long as SLUB does not have to handle partial |
| * slabs, operations can continue without any centralized lock. F.e. |
| * allocating a long series of objects that fill up slabs does not require |
| * the list lock. |
| * |
| * The lock order is sometimes inverted when we are trying to get a slab |
| * off a list. We take the list_lock and then look for a page on the list |
| * to use. While we do that objects in the slabs may be freed. We can |
| * only operate on the slab if we have also taken the slab_lock. So we use |
| * a slab_trylock() on the slab. If trylock was successful then no frees |
| * can occur anymore and we can use the slab for allocations etc. If the |
| * slab_trylock() does not succeed then frees are in progress in the slab and |
| * we must stay away from it for a while since we may cause a bouncing |
| * cacheline if we try to acquire the lock. So go onto the next slab. |
| * If all pages are busy then we may allocate a new slab instead of reusing |
| * a partial slab. A new slab has noone operating on it and thus there is |
| * no danger of cacheline contention. |
| * |
| * Interrupts are disabled during allocation and deallocation in order to |
| * make the slab allocator safe to use in the context of an irq. In addition |
| * interrupts are disabled to ensure that the processor does not change |
| * while handling per_cpu slabs, due to kernel preemption. |
| * |
| * SLUB assigns one slab for allocation to each processor. |
| * Allocations only occur from these slabs called cpu slabs. |
| * |
| * Slabs with free elements are kept on a partial list. |
| * There is no list for full slabs. If an object in a full slab is |
| * freed then the slab will show up again on the partial lists. |
| * Otherwise there is no need to track full slabs unless we have to |
| * track full slabs for debugging purposes. |
| * |
| * Slabs are freed when they become empty. Teardown and setup is |
| * minimal so we rely on the page allocators per cpu caches for |
| * fast frees and allocs. |
| * |
| * Overloading of page flags that are otherwise used for LRU management. |
| * |
| * PageActive The slab is used as a cpu cache. Allocations |
| * may be performed from the slab. The slab is not |
| * on any slab list and cannot be moved onto one. |
| * |
| * PageError Slab requires special handling due to debug |
| * options set. This moves slab handling out of |
| * the fast path. |
| */ |
| |
| /* |
| * Issues still to be resolved: |
| * |
| * - The per cpu array is updated for each new slab and and is a remote |
| * cacheline for most nodes. This could become a bouncing cacheline given |
| * enough frequent updates. There are 16 pointers in a cacheline.so at |
| * max 16 cpus could compete. Likely okay. |
| * |
| * - Support PAGE_ALLOC_DEBUG. Should be easy to do. |
| * |
| * - Support DEBUG_SLAB_LEAK. Trouble is we do not know where the full |
| * slabs are in SLUB. |
| * |
| * - SLAB_DEBUG_INITIAL is not supported but I have never seen a use of |
| * it. |
| * |
| * - Variable sizing of the per node arrays |
| */ |
| |
| /* Enable to test recovery from slab corruption on boot */ |
| #undef SLUB_RESILIENCY_TEST |
| |
| #if PAGE_SHIFT <= 12 |
| |
| /* |
| * Small page size. Make sure that we do not fragment memory |
| */ |
| #define DEFAULT_MAX_ORDER 1 |
| #define DEFAULT_MIN_OBJECTS 4 |
| |
| #else |
| |
| /* |
| * Large page machines are customarily able to handle larger |
| * page orders. |
| */ |
| #define DEFAULT_MAX_ORDER 2 |
| #define DEFAULT_MIN_OBJECTS 8 |
| |
| #endif |
| |
| /* |
| * Flags from the regular SLAB that SLUB does not support: |
| */ |
| #define SLUB_UNIMPLEMENTED (SLAB_DEBUG_INITIAL) |
| |
| #define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \ |
| SLAB_POISON | SLAB_STORE_USER) |
| /* |
| * Set of flags that will prevent slab merging |
| */ |
| #define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ |
| SLAB_TRACE | SLAB_DESTROY_BY_RCU) |
| |
| #define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \ |
| SLAB_CACHE_DMA) |
| |
| #ifndef ARCH_KMALLOC_MINALIGN |
| #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) |
| #endif |
| |
| #ifndef ARCH_SLAB_MINALIGN |
| #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long) |
| #endif |
| |
| /* Internal SLUB flags */ |
| #define __OBJECT_POISON 0x80000000 /* Poison object */ |
| |
| static int kmem_size = sizeof(struct kmem_cache); |
| |
| #ifdef CONFIG_SMP |
| static struct notifier_block slab_notifier; |
| #endif |
| |
| static enum { |
| DOWN, /* No slab functionality available */ |
| PARTIAL, /* kmem_cache_open() works but kmalloc does not */ |
| UP, /* Everything works */ |
| SYSFS /* Sysfs up */ |
| } slab_state = DOWN; |
| |
| /* A list of all slab caches on the system */ |
| static DECLARE_RWSEM(slub_lock); |
| LIST_HEAD(slab_caches); |
| |
| #ifdef CONFIG_SYSFS |
| static int sysfs_slab_add(struct kmem_cache *); |
| static int sysfs_slab_alias(struct kmem_cache *, const char *); |
| static void sysfs_slab_remove(struct kmem_cache *); |
| #else |
| static int sysfs_slab_add(struct kmem_cache *s) { return 0; } |
| static int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; } |
| static void sysfs_slab_remove(struct kmem_cache *s) {} |
| #endif |
| |
| /******************************************************************** |
| * Core slab cache functions |
| *******************************************************************/ |
| |
| int slab_is_available(void) |
| { |
| return slab_state >= UP; |
| } |
| |
| static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) |
| { |
| #ifdef CONFIG_NUMA |
| return s->node[node]; |
| #else |
| return &s->local_node; |
| #endif |
| } |
| |
| /* |
| * Object debugging |
| */ |
| static void print_section(char *text, u8 *addr, unsigned int length) |
| { |
| int i, offset; |
| int newline = 1; |
| char ascii[17]; |
| |
| ascii[16] = 0; |
| |
| for (i = 0; i < length; i++) { |
| if (newline) { |
| printk(KERN_ERR "%10s 0x%p: ", text, addr + i); |
| newline = 0; |
| } |
| printk(" %02x", addr[i]); |
| offset = i % 16; |
| ascii[offset] = isgraph(addr[i]) ? addr[i] : '.'; |
| if (offset == 15) { |
| printk(" %s\n",ascii); |
| newline = 1; |
| } |
| } |
| if (!newline) { |
| i %= 16; |
| while (i < 16) { |
| printk(" "); |
| ascii[i] = ' '; |
| i++; |
| } |
| printk(" %s\n", ascii); |
| } |
| } |
| |
| /* |
| * Slow version of get and set free pointer. |
| * |
| * This requires touching the cache lines of kmem_cache. |
| * The offset can also be obtained from the page. In that |
| * case it is in the cacheline that we already need to touch. |
| */ |
| static void *get_freepointer(struct kmem_cache *s, void *object) |
| { |
| return *(void **)(object + s->offset); |
| } |
| |
| static void set_freepointer(struct kmem_cache *s, void *object, void *fp) |
| { |
| *(void **)(object + s->offset) = fp; |
| } |
| |
| /* |
| * Tracking user of a slab. |
| */ |
| struct track { |
| void *addr; /* Called from address */ |
| int cpu; /* Was running on cpu */ |
| int pid; /* Pid context */ |
| unsigned long when; /* When did the operation occur */ |
| }; |
| |
| enum track_item { TRACK_ALLOC, TRACK_FREE }; |
| |
| static struct track *get_track(struct kmem_cache *s, void *object, |
| enum track_item alloc) |
| { |
| struct track *p; |
| |
| if (s->offset) |
| p = object + s->offset + sizeof(void *); |
| else |
| p = object + s->inuse; |
| |
| return p + alloc; |
| } |
| |
| static void set_track(struct kmem_cache *s, void *object, |
| enum track_item alloc, void *addr) |
| { |
| struct track *p; |
| |
| if (s->offset) |
| p = object + s->offset + sizeof(void *); |
| else |
| p = object + s->inuse; |
| |
| p += alloc; |
| if (addr) { |
| p->addr = addr; |
| p->cpu = smp_processor_id(); |
| p->pid = current ? current->pid : -1; |
| p->when = jiffies; |
| } else |
| memset(p, 0, sizeof(struct track)); |
| } |
| |
| #define set_tracking(__s, __o, __a) set_track(__s, __o, __a, \ |
| __builtin_return_address(0)) |
| |
| static void init_tracking(struct kmem_cache *s, void *object) |
| { |
| if (s->flags & SLAB_STORE_USER) { |
| set_track(s, object, TRACK_FREE, NULL); |
| set_track(s, object, TRACK_ALLOC, NULL); |
| } |
| } |
| |
| static void print_track(const char *s, struct track *t) |
| { |
| if (!t->addr) |
| return; |
| |
| printk(KERN_ERR "%s: ", s); |
| __print_symbol("%s", (unsigned long)t->addr); |
| printk(" jiffies_ago=%lu cpu=%u pid=%d\n", jiffies - t->when, t->cpu, t->pid); |
| } |
| |
| static void print_trailer(struct kmem_cache *s, u8 *p) |
| { |
| unsigned int off; /* Offset of last byte */ |
| |
| if (s->flags & SLAB_RED_ZONE) |
| print_section("Redzone", p + s->objsize, |
| s->inuse - s->objsize); |
| |
| printk(KERN_ERR "FreePointer 0x%p -> 0x%p\n", |
| p + s->offset, |
| get_freepointer(s, p)); |
| |
| if (s->offset) |
| off = s->offset + sizeof(void *); |
| else |
| off = s->inuse; |
| |
| if (s->flags & SLAB_STORE_USER) { |
| print_track("Last alloc", get_track(s, p, TRACK_ALLOC)); |
| print_track("Last free ", get_track(s, p, TRACK_FREE)); |
| off += 2 * sizeof(struct track); |
| } |
| |
| if (off != s->size) |
| /* Beginning of the filler is the free pointer */ |
| print_section("Filler", p + off, s->size - off); |
| } |
| |
| static void object_err(struct kmem_cache *s, struct page *page, |
| u8 *object, char *reason) |
| { |
| u8 *addr = page_address(page); |
| |
| printk(KERN_ERR "*** SLUB %s: %s@0x%p slab 0x%p\n", |
| s->name, reason, object, page); |
| printk(KERN_ERR " offset=%tu flags=0x%04lx inuse=%u freelist=0x%p\n", |
| object - addr, page->flags, page->inuse, page->freelist); |
| if (object > addr + 16) |
| print_section("Bytes b4", object - 16, 16); |
| print_section("Object", object, min(s->objsize, 128)); |
| print_trailer(s, object); |
| dump_stack(); |
| } |
| |
| static void slab_err(struct kmem_cache *s, struct page *page, char *reason, ...) |
| { |
| va_list args; |
| char buf[100]; |
| |
| va_start(args, reason); |
| vsnprintf(buf, sizeof(buf), reason, args); |
| va_end(args); |
| printk(KERN_ERR "*** SLUB %s: %s in slab @0x%p\n", s->name, buf, |
| page); |
| dump_stack(); |
| } |
| |
| static void init_object(struct kmem_cache *s, void *object, int active) |
| { |
| u8 *p = object; |
| |
| if (s->flags & __OBJECT_POISON) { |
| memset(p, POISON_FREE, s->objsize - 1); |
| p[s->objsize -1] = POISON_END; |
| } |
| |
| if (s->flags & SLAB_RED_ZONE) |
| memset(p + s->objsize, |
| active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE, |
| s->inuse - s->objsize); |
| } |
| |
| static int check_bytes(u8 *start, unsigned int value, unsigned int bytes) |
| { |
| while (bytes) { |
| if (*start != (u8)value) |
| return 0; |
| start++; |
| bytes--; |
| } |
| return 1; |
| } |
| |
| |
| static int check_valid_pointer(struct kmem_cache *s, struct page *page, |
| void *object) |
| { |
| void *base; |
| |
| if (!object) |
| return 1; |
| |
| base = page_address(page); |
| if (object < base || object >= base + s->objects * s->size || |
| (object - base) % s->size) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* |
| * Object layout: |
| * |
| * object address |
| * Bytes of the object to be managed. |
| * If the freepointer may overlay the object then the free |
| * pointer is the first word of the object. |
| * Poisoning uses 0x6b (POISON_FREE) and the last byte is |
| * 0xa5 (POISON_END) |
| * |
| * object + s->objsize |
| * Padding to reach word boundary. This is also used for Redzoning. |
| * Padding is extended to word size if Redzoning is enabled |
| * and objsize == inuse. |
| * We fill with 0xbb (RED_INACTIVE) for inactive objects and with |
| * 0xcc (RED_ACTIVE) for objects in use. |
| * |
| * object + s->inuse |
| * A. Free pointer (if we cannot overwrite object on free) |
| * B. Tracking data for SLAB_STORE_USER |
| * C. Padding to reach required alignment boundary |
| * Padding is done using 0x5a (POISON_INUSE) |
| * |
| * object + s->size |
| * |
| * If slabcaches are merged then the objsize and inuse boundaries are to |
| * be ignored. And therefore no slab options that rely on these boundaries |
| * may be used with merged slabcaches. |
| */ |
| |
| static void restore_bytes(struct kmem_cache *s, char *message, u8 data, |
| void *from, void *to) |
| { |
| printk(KERN_ERR "@@@ SLUB: %s Restoring %s (0x%x) from 0x%p-0x%p\n", |
| s->name, message, data, from, to - 1); |
| memset(from, data, to - from); |
| } |
| |
| static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) |
| { |
| unsigned long off = s->inuse; /* The end of info */ |
| |
| if (s->offset) |
| /* Freepointer is placed after the object. */ |
| off += sizeof(void *); |
| |
| if (s->flags & SLAB_STORE_USER) |
| /* We also have user information there */ |
| off += 2 * sizeof(struct track); |
| |
| if (s->size == off) |
| return 1; |
| |
| if (check_bytes(p + off, POISON_INUSE, s->size - off)) |
| return 1; |
| |
| object_err(s, page, p, "Object padding check fails"); |
| |
| /* |
| * Restore padding |
| */ |
| restore_bytes(s, "object padding", POISON_INUSE, p + off, p + s->size); |
| return 0; |
| } |
| |
| static int slab_pad_check(struct kmem_cache *s, struct page *page) |
| { |
| u8 *p; |
| int length, remainder; |
| |
| if (!(s->flags & SLAB_POISON)) |
| return 1; |
| |
| p = page_address(page); |
| length = s->objects * s->size; |
| remainder = (PAGE_SIZE << s->order) - length; |
| if (!remainder) |
| return 1; |
| |
| if (!check_bytes(p + length, POISON_INUSE, remainder)) { |
| printk(KERN_ERR "SLUB: %s slab 0x%p: Padding fails check\n", |
| s->name, p); |
| dump_stack(); |
| restore_bytes(s, "slab padding", POISON_INUSE, p + length, |
| p + length + remainder); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static int check_object(struct kmem_cache *s, struct page *page, |
| void *object, int active) |
| { |
| u8 *p = object; |
| u8 *endobject = object + s->objsize; |
| |
| if (s->flags & SLAB_RED_ZONE) { |
| unsigned int red = |
| active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE; |
| |
| if (!check_bytes(endobject, red, s->inuse - s->objsize)) { |
| object_err(s, page, object, |
| active ? "Redzone Active" : "Redzone Inactive"); |
| restore_bytes(s, "redzone", red, |
| endobject, object + s->inuse); |
| return 0; |
| } |
| } else { |
| if ((s->flags & SLAB_POISON) && s->objsize < s->inuse && |
| !check_bytes(endobject, POISON_INUSE, |
| s->inuse - s->objsize)) { |
| object_err(s, page, p, "Alignment padding check fails"); |
| /* |
| * Fix it so that there will not be another report. |
| * |
| * Hmmm... We may be corrupting an object that now expects |
| * to be longer than allowed. |
| */ |
| restore_bytes(s, "alignment padding", POISON_INUSE, |
| endobject, object + s->inuse); |
| } |
| } |
| |
| if (s->flags & SLAB_POISON) { |
| if (!active && (s->flags & __OBJECT_POISON) && |
| (!check_bytes(p, POISON_FREE, s->objsize - 1) || |
| p[s->objsize - 1] != POISON_END)) { |
| |
| object_err(s, page, p, "Poison check failed"); |
| restore_bytes(s, "Poison", POISON_FREE, |
| p, p + s->objsize -1); |
| restore_bytes(s, "Poison", POISON_END, |
| p + s->objsize - 1, p + s->objsize); |
| return 0; |
| } |
| /* |
| * check_pad_bytes cleans up on its own. |
| */ |
| check_pad_bytes(s, page, p); |
| } |
| |
| if (!s->offset && active) |
| /* |
| * Object and freepointer overlap. Cannot check |
| * freepointer while object is allocated. |
| */ |
| return 1; |
| |
| /* Check free pointer validity */ |
| if (!check_valid_pointer(s, page, get_freepointer(s, p))) { |
| object_err(s, page, p, "Freepointer corrupt"); |
| /* |
| * No choice but to zap it and thus loose the remainder |
| * of the free objects in this slab. May cause |
| * another error because the object count maybe |
| * wrong now. |
| */ |
| set_freepointer(s, p, NULL); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static int check_slab(struct kmem_cache *s, struct page *page) |
| { |
| VM_BUG_ON(!irqs_disabled()); |
| |
| if (!PageSlab(page)) { |
| printk(KERN_ERR "SLUB: %s Not a valid slab page @0x%p " |
| "flags=%lx mapping=0x%p count=%d \n", |
| s->name, page, page->flags, page->mapping, |
| page_count(page)); |
| return 0; |
| } |
| if (page->offset * sizeof(void *) != s->offset) { |
| printk(KERN_ERR "SLUB: %s Corrupted offset %lu in slab @0x%p" |
| " flags=0x%lx mapping=0x%p count=%d\n", |
| s->name, |
| (unsigned long)(page->offset * sizeof(void *)), |
| page, |
| page->flags, |
| page->mapping, |
| page_count(page)); |
| dump_stack(); |
| return 0; |
| } |
| if (page->inuse > s->objects) { |
| printk(KERN_ERR "SLUB: %s Inuse %u > max %u in slab " |
| "page @0x%p flags=%lx mapping=0x%p count=%d\n", |
| s->name, page->inuse, s->objects, page, page->flags, |
| page->mapping, page_count(page)); |
| dump_stack(); |
| return 0; |
| } |
| /* Slab_pad_check fixes things up after itself */ |
| slab_pad_check(s, page); |
| return 1; |
| } |
| |
| /* |
| * Determine if a certain object on a page is on the freelist and |
| * therefore free. Must hold the slab lock for cpu slabs to |
| * guarantee that the chains are consistent. |
| */ |
| static int on_freelist(struct kmem_cache *s, struct page *page, void *search) |
| { |
| int nr = 0; |
| void *fp = page->freelist; |
| void *object = NULL; |
| |
| while (fp && nr <= s->objects) { |
| if (fp == search) |
| return 1; |
| if (!check_valid_pointer(s, page, fp)) { |
| if (object) { |
| object_err(s, page, object, |
| "Freechain corrupt"); |
| set_freepointer(s, object, NULL); |
| break; |
| } else { |
| printk(KERN_ERR "SLUB: %s slab 0x%p " |
| "freepointer 0x%p corrupted.\n", |
| s->name, page, fp); |
| dump_stack(); |
| page->freelist = NULL; |
| page->inuse = s->objects; |
| return 0; |
| } |
| break; |
| } |
| object = fp; |
| fp = get_freepointer(s, object); |
| nr++; |
| } |
| |
| if (page->inuse != s->objects - nr) { |
| printk(KERN_ERR "slab %s: page 0x%p wrong object count." |
| " counter is %d but counted were %d\n", |
| s->name, page, page->inuse, |
| s->objects - nr); |
| page->inuse = s->objects - nr; |
| } |
| return search == NULL; |
| } |
| |
| static int alloc_object_checks(struct kmem_cache *s, struct page *page, |
| void *object) |
| { |
| if (!check_slab(s, page)) |
| goto bad; |
| |
| if (object && !on_freelist(s, page, object)) { |
| printk(KERN_ERR "SLUB: %s Object 0x%p@0x%p " |
| "already allocated.\n", |
| s->name, object, page); |
| goto dump; |
| } |
| |
| if (!check_valid_pointer(s, page, object)) { |
| object_err(s, page, object, "Freelist Pointer check fails"); |
| goto dump; |
| } |
| |
| if (!object) |
| return 1; |
| |
| if (!check_object(s, page, object, 0)) |
| goto bad; |
| init_object(s, object, 1); |
| |
| if (s->flags & SLAB_TRACE) { |
| printk(KERN_INFO "TRACE %s alloc 0x%p inuse=%d fp=0x%p\n", |
| s->name, object, page->inuse, |
| page->freelist); |
| dump_stack(); |
| } |
| return 1; |
| dump: |
| dump_stack(); |
| bad: |
| if (PageSlab(page)) { |
| /* |
| * If this is a slab page then lets do the best we can |
| * to avoid issues in the future. Marking all objects |
| * as used avoids touching the remainder. |
| */ |
| printk(KERN_ERR "@@@ SLUB: %s slab 0x%p. Marking all objects used.\n", |
| s->name, page); |
| page->inuse = s->objects; |
| page->freelist = NULL; |
| /* Fix up fields that may be corrupted */ |
| page->offset = s->offset / sizeof(void *); |
| } |
| return 0; |
| } |
| |
| static int free_object_checks(struct kmem_cache *s, struct page *page, |
| void *object) |
| { |
| if (!check_slab(s, page)) |
| goto fail; |
| |
| if (!check_valid_pointer(s, page, object)) { |
| printk(KERN_ERR "SLUB: %s slab 0x%p invalid " |
| "object pointer 0x%p\n", |
| s->name, page, object); |
| goto fail; |
| } |
| |
| if (on_freelist(s, page, object)) { |
| printk(KERN_ERR "SLUB: %s slab 0x%p object " |
| "0x%p already free.\n", s->name, page, object); |
| goto fail; |
| } |
| |
| if (!check_object(s, page, object, 1)) |
| return 0; |
| |
| if (unlikely(s != page->slab)) { |
| if (!PageSlab(page)) |
| printk(KERN_ERR "slab_free %s size %d: attempt to" |
| "free object(0x%p) outside of slab.\n", |
| s->name, s->size, object); |
| else |
| if (!page->slab) |
| printk(KERN_ERR |
| "slab_free : no slab(NULL) for object 0x%p.\n", |
| object); |
| else |
| printk(KERN_ERR "slab_free %s(%d): object at 0x%p" |
| " belongs to slab %s(%d)\n", |
| s->name, s->size, object, |
| page->slab->name, page->slab->size); |
| goto fail; |
| } |
| if (s->flags & SLAB_TRACE) { |
| printk(KERN_INFO "TRACE %s free 0x%p inuse=%d fp=0x%p\n", |
| s->name, object, page->inuse, |
| page->freelist); |
| print_section("Object", object, s->objsize); |
| dump_stack(); |
| } |
| init_object(s, object, 0); |
| return 1; |
| fail: |
| dump_stack(); |
| printk(KERN_ERR "@@@ SLUB: %s slab 0x%p object at 0x%p not freed.\n", |
| s->name, page, object); |
| return 0; |
| } |
| |
| /* |
| * Slab allocation and freeing |
| */ |
| static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) |
| { |
| struct page * page; |
| int pages = 1 << s->order; |
| |
| if (s->order) |
| flags |= __GFP_COMP; |
| |
| if (s->flags & SLAB_CACHE_DMA) |
| flags |= SLUB_DMA; |
| |
| if (node == -1) |
| page = alloc_pages(flags, s->order); |
| else |
| page = alloc_pages_node(node, flags, s->order); |
| |
| if (!page) |
| return NULL; |
| |
| mod_zone_page_state(page_zone(page), |
| (s->flags & SLAB_RECLAIM_ACCOUNT) ? |
| NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, |
| pages); |
| |
| return page; |
| } |
| |
| static void setup_object(struct kmem_cache *s, struct page *page, |
| void *object) |
| { |
| if (PageError(page)) { |
| init_object(s, object, 0); |
| init_tracking(s, object); |
| } |
| |
| if (unlikely(s->ctor)) { |
| int mode = SLAB_CTOR_CONSTRUCTOR; |
| |
| if (!(s->flags & __GFP_WAIT)) |
| mode |= SLAB_CTOR_ATOMIC; |
| |
| s->ctor(object, s, mode); |
| } |
| } |
| |
| static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) |
| { |
| struct page *page; |
| struct kmem_cache_node *n; |
| void *start; |
| void *end; |
| void *last; |
| void *p; |
| |
| if (flags & __GFP_NO_GROW) |
| return NULL; |
| |
| BUG_ON(flags & ~(GFP_DMA | GFP_LEVEL_MASK)); |
| |
| if (flags & __GFP_WAIT) |
| local_irq_enable(); |
| |
| page = allocate_slab(s, flags & GFP_LEVEL_MASK, node); |
| if (!page) |
| goto out; |
| |
| n = get_node(s, page_to_nid(page)); |
| if (n) |
| atomic_long_inc(&n->nr_slabs); |
| page->offset = s->offset / sizeof(void *); |
| page->slab = s; |
| page->flags |= 1 << PG_slab; |
| if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON | |
| SLAB_STORE_USER | SLAB_TRACE)) |
| page->flags |= 1 << PG_error; |
| |
| start = page_address(page); |
| end = start + s->objects * s->size; |
| |
| if (unlikely(s->flags & SLAB_POISON)) |
| memset(start, POISON_INUSE, PAGE_SIZE << s->order); |
| |
| last = start; |
| for (p = start + s->size; p < end; p += s->size) { |
| setup_object(s, page, last); |
| set_freepointer(s, last, p); |
| last = p; |
| } |
| setup_object(s, page, last); |
| set_freepointer(s, last, NULL); |
| |
| page->freelist = start; |
| page->inuse = 0; |
| out: |
| if (flags & __GFP_WAIT) |
| local_irq_disable(); |
| return page; |
| } |
| |
| static void __free_slab(struct kmem_cache *s, struct page *page) |
| { |
| int pages = 1 << s->order; |
| |
| if (unlikely(PageError(page) || s->dtor)) { |
| void *start = page_address(page); |
| void *end = start + (pages << PAGE_SHIFT); |
| void *p; |
| |
| slab_pad_check(s, page); |
| for (p = start; p <= end - s->size; p += s->size) { |
| if (s->dtor) |
| s->dtor(p, s, 0); |
| check_object(s, page, p, 0); |
| } |
| } |
| |
| mod_zone_page_state(page_zone(page), |
| (s->flags & SLAB_RECLAIM_ACCOUNT) ? |
| NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, |
| - pages); |
| |
| page->mapping = NULL; |
| __free_pages(page, s->order); |
| } |
| |
| static void rcu_free_slab(struct rcu_head *h) |
| { |
| struct page *page; |
| |
| page = container_of((struct list_head *)h, struct page, lru); |
| __free_slab(page->slab, page); |
| } |
| |
| static void free_slab(struct kmem_cache *s, struct page *page) |
| { |
| if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) { |
| /* |
| * RCU free overloads the RCU head over the LRU |
| */ |
| struct rcu_head *head = (void *)&page->lru; |
| |
| call_rcu(head, rcu_free_slab); |
| } else |
| __free_slab(s, page); |
| } |
| |
| static void discard_slab(struct kmem_cache *s, struct page *page) |
| { |
| struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
| |
| atomic_long_dec(&n->nr_slabs); |
| reset_page_mapcount(page); |
| page->flags &= ~(1 << PG_slab | 1 << PG_error); |
| free_slab(s, page); |
| } |
| |
| /* |
| * Per slab locking using the pagelock |
| */ |
| static __always_inline void slab_lock(struct page *page) |
| { |
| bit_spin_lock(PG_locked, &page->flags); |
| } |
| |
| static __always_inline void slab_unlock(struct page *page) |
| { |
| bit_spin_unlock(PG_locked, &page->flags); |
| } |
| |
| static __always_inline int slab_trylock(struct page *page) |
| { |
| int rc = 1; |
| |
| rc = bit_spin_trylock(PG_locked, &page->flags); |
| return rc; |
| } |
| |
| /* |
| * Management of partially allocated slabs |
| */ |
| static void add_partial(struct kmem_cache *s, struct page *page) |
| { |
| struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
| |
| spin_lock(&n->list_lock); |
| n->nr_partial++; |
| list_add(&page->lru, &n->partial); |
| spin_unlock(&n->list_lock); |
| } |
| |
| static void remove_partial(struct kmem_cache *s, |
| struct page *page) |
| { |
| struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
| |
| spin_lock(&n->list_lock); |
| list_del(&page->lru); |
| n->nr_partial--; |
| spin_unlock(&n->list_lock); |
| } |
| |
| /* |
| * Lock page and remove it from the partial list |
| * |
| * Must hold list_lock |
| */ |
| static int lock_and_del_slab(struct kmem_cache_node *n, struct page *page) |
| { |
| if (slab_trylock(page)) { |
| list_del(&page->lru); |
| n->nr_partial--; |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* |
| * Try to get a partial slab from a specific node |
| */ |
| static struct page *get_partial_node(struct kmem_cache_node *n) |
| { |
| struct page *page; |
| |
| /* |
| * Racy check. If we mistakenly see no partial slabs then we |
| * just allocate an empty slab. If we mistakenly try to get a |
| * partial slab then get_partials() will return NULL. |
| */ |
| if (!n || !n->nr_partial) |
| return NULL; |
| |
| spin_lock(&n->list_lock); |
| list_for_each_entry(page, &n->partial, lru) |
| if (lock_and_del_slab(n, page)) |
| goto out; |
| page = NULL; |
| out: |
| spin_unlock(&n->list_lock); |
| return page; |
| } |
| |
| /* |
| * Get a page from somewhere. Search in increasing NUMA |
| * distances. |
| */ |
| static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags) |
| { |
| #ifdef CONFIG_NUMA |
| struct zonelist *zonelist; |
| struct zone **z; |
| struct page *page; |
| |
| /* |
| * The defrag ratio allows to configure the tradeoffs between |
| * inter node defragmentation and node local allocations. |
| * A lower defrag_ratio increases the tendency to do local |
| * allocations instead of scanning throught the partial |
| * lists on other nodes. |
| * |
| * If defrag_ratio is set to 0 then kmalloc() always |
| * returns node local objects. If its higher then kmalloc() |
| * may return off node objects in order to avoid fragmentation. |
| * |
| * A higher ratio means slabs may be taken from other nodes |
| * thus reducing the number of partial slabs on those nodes. |
| * |
| * If /sys/slab/xx/defrag_ratio is set to 100 (which makes |
| * defrag_ratio = 1000) then every (well almost) allocation |
| * will first attempt to defrag slab caches on other nodes. This |
| * means scanning over all nodes to look for partial slabs which |
| * may be a bit expensive to do on every slab allocation. |
| */ |
| if (!s->defrag_ratio || get_cycles() % 1024 > s->defrag_ratio) |
| return NULL; |
| |
| zonelist = &NODE_DATA(slab_node(current->mempolicy)) |
| ->node_zonelists[gfp_zone(flags)]; |
| for (z = zonelist->zones; *z; z++) { |
| struct kmem_cache_node *n; |
| |
| n = get_node(s, zone_to_nid(*z)); |
| |
| if (n && cpuset_zone_allowed_hardwall(*z, flags) && |
| n->nr_partial > 2) { |
| page = get_partial_node(n); |
| if (page) |
| return page; |
| } |
| } |
| #endif |
| return NULL; |
| } |
| |
| /* |
| * Get a partial page, lock it and return it. |
| */ |
| static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node) |
| { |
| struct page *page; |
| int searchnode = (node == -1) ? numa_node_id() : node; |
| |
| page = get_partial_node(get_node(s, searchnode)); |
| if (page || (flags & __GFP_THISNODE)) |
| return page; |
| |
| return get_any_partial(s, flags); |
| } |
| |
| /* |
| * Move a page back to the lists. |
| * |
| * Must be called with the slab lock held. |
| * |
| * On exit the slab lock will have been dropped. |
| */ |
| static void putback_slab(struct kmem_cache *s, struct page *page) |
| { |
| if (page->inuse) { |
| if (page->freelist) |
| add_partial(s, page); |
| slab_unlock(page); |
| } else { |
| slab_unlock(page); |
| discard_slab(s, page); |
| } |
| } |
| |
| /* |
| * Remove the cpu slab |
| */ |
| static void deactivate_slab(struct kmem_cache *s, struct page *page, int cpu) |
| { |
| s->cpu_slab[cpu] = NULL; |
| ClearPageActive(page); |
| |
| putback_slab(s, page); |
| } |
| |
| static void flush_slab(struct kmem_cache *s, struct page *page, int cpu) |
| { |
| slab_lock(page); |
| deactivate_slab(s, page, cpu); |
| } |
| |
| /* |
| * Flush cpu slab. |
| * Called from IPI handler with interrupts disabled. |
| */ |
| static void __flush_cpu_slab(struct kmem_cache *s, int cpu) |
| { |
| struct page *page = s->cpu_slab[cpu]; |
| |
| if (likely(page)) |
| flush_slab(s, page, cpu); |
| } |
| |
| static void flush_cpu_slab(void *d) |
| { |
| struct kmem_cache *s = d; |
| int cpu = smp_processor_id(); |
| |
| __flush_cpu_slab(s, cpu); |
| } |
| |
| static void flush_all(struct kmem_cache *s) |
| { |
| #ifdef CONFIG_SMP |
| on_each_cpu(flush_cpu_slab, s, 1, 1); |
| #else |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| flush_cpu_slab(s); |
| local_irq_restore(flags); |
| #endif |
| } |
| |
| /* |
| * slab_alloc is optimized to only modify two cachelines on the fast path |
| * (aside from the stack): |
| * |
| * 1. The page struct |
| * 2. The first cacheline of the object to be allocated. |
| * |
| * The only cache lines that are read (apart from code) is the |
| * per cpu array in the kmem_cache struct. |
| * |
| * Fastpath is not possible if we need to get a new slab or have |
| * debugging enabled (which means all slabs are marked with PageError) |
| */ |
| static __always_inline void *slab_alloc(struct kmem_cache *s, |
| gfp_t gfpflags, int node) |
| { |
| struct page *page; |
| void **object; |
| unsigned long flags; |
| int cpu; |
| |
| local_irq_save(flags); |
| cpu = smp_processor_id(); |
| page = s->cpu_slab[cpu]; |
| if (!page) |
| goto new_slab; |
| |
| slab_lock(page); |
| if (unlikely(node != -1 && page_to_nid(page) != node)) |
| goto another_slab; |
| redo: |
| object = page->freelist; |
| if (unlikely(!object)) |
| goto another_slab; |
| if (unlikely(PageError(page))) |
| goto debug; |
| |
| have_object: |
| page->inuse++; |
| page->freelist = object[page->offset]; |
| slab_unlock(page); |
| local_irq_restore(flags); |
| return object; |
| |
| another_slab: |
| deactivate_slab(s, page, cpu); |
| |
| new_slab: |
| page = get_partial(s, gfpflags, node); |
| if (likely(page)) { |
| have_slab: |
| s->cpu_slab[cpu] = page; |
| SetPageActive(page); |
| goto redo; |
| } |
| |
| page = new_slab(s, gfpflags, node); |
| if (page) { |
| cpu = smp_processor_id(); |
| if (s->cpu_slab[cpu]) { |
| /* |
| * Someone else populated the cpu_slab while we enabled |
| * interrupts, or we have got scheduled on another cpu. |
| * The page may not be on the requested node. |
| */ |
| if (node == -1 || |
| page_to_nid(s->cpu_slab[cpu]) == node) { |
| /* |
| * Current cpuslab is acceptable and we |
| * want the current one since its cache hot |
| */ |
| discard_slab(s, page); |
| page = s->cpu_slab[cpu]; |
| slab_lock(page); |
| goto redo; |
| } |
| /* Dump the current slab */ |
| flush_slab(s, s->cpu_slab[cpu], cpu); |
| } |
| slab_lock(page); |
| goto have_slab; |
| } |
| local_irq_restore(flags); |
| return NULL; |
| debug: |
| if (!alloc_object_checks(s, page, object)) |
| goto another_slab; |
| if (s->flags & SLAB_STORE_USER) |
| set_tracking(s, object, TRACK_ALLOC); |
| goto have_object; |
| } |
| |
| void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) |
| { |
| return slab_alloc(s, gfpflags, -1); |
| } |
| EXPORT_SYMBOL(kmem_cache_alloc); |
| |
| #ifdef CONFIG_NUMA |
| void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) |
| { |
| return slab_alloc(s, gfpflags, node); |
| } |
| EXPORT_SYMBOL(kmem_cache_alloc_node); |
| #endif |
| |
| /* |
| * The fastpath only writes the cacheline of the page struct and the first |
| * cacheline of the object. |
| * |
| * No special cachelines need to be read |
| */ |
| static void slab_free(struct kmem_cache *s, struct page *page, void *x) |
| { |
| void *prior; |
| void **object = (void *)x; |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| slab_lock(page); |
| |
| if (unlikely(PageError(page))) |
| goto debug; |
| checks_ok: |
| prior = object[page->offset] = page->freelist; |
| page->freelist = object; |
| page->inuse--; |
| |
| if (unlikely(PageActive(page))) |
| /* |
| * Cpu slabs are never on partial lists and are |
| * never freed. |
| */ |
| goto out_unlock; |
| |
| if (unlikely(!page->inuse)) |
| goto slab_empty; |
| |
| /* |
| * Objects left in the slab. If it |
| * was not on the partial list before |
| * then add it. |
| */ |
| if (unlikely(!prior)) |
| add_partial(s, page); |
| |
| out_unlock: |
| slab_unlock(page); |
| local_irq_restore(flags); |
| return; |
| |
| slab_empty: |
| if (prior) |
| /* |
| * Partially used slab that is on the partial list. |
| */ |
| remove_partial(s, page); |
| |
| slab_unlock(page); |
| discard_slab(s, page); |
| local_irq_restore(flags); |
| return; |
| |
| debug: |
| if (free_object_checks(s, page, x)) |
| goto checks_ok; |
| goto out_unlock; |
| } |
| |
| void kmem_cache_free(struct kmem_cache *s, void *x) |
| { |
| struct page * page; |
| |
| page = virt_to_page(x); |
| |
| if (unlikely(PageCompound(page))) |
| page = page->first_page; |
| |
| |
| if (unlikely(PageError(page) && (s->flags & SLAB_STORE_USER))) |
| set_tracking(s, x, TRACK_FREE); |
| slab_free(s, page, x); |
| } |
| EXPORT_SYMBOL(kmem_cache_free); |
| |
| /* Figure out on which slab object the object resides */ |
| static struct page *get_object_page(const void *x) |
| { |
| struct page *page = virt_to_page(x); |
| |
| if (unlikely(PageCompound(page))) |
| page = page->first_page; |
| |
| if (!PageSlab(page)) |
| return NULL; |
| |
| return page; |
| } |
| |
| /* |
| * kmem_cache_open produces objects aligned at "size" and the first object |
| * is placed at offset 0 in the slab (We have no metainformation on the |
| * slab, all slabs are in essence "off slab"). |
| * |
| * In order to get the desired alignment one just needs to align the |
| * size. |
| * |
| * Notice that the allocation order determines the sizes of the per cpu |
| * caches. Each processor has always one slab available for allocations. |
| * Increasing the allocation order reduces the number of times that slabs |
| * must be moved on and off the partial lists and therefore may influence |
| * locking overhead. |
| * |
| * The offset is used to relocate the free list link in each object. It is |
| * therefore possible to move the free list link behind the object. This |
| * is necessary for RCU to work properly and also useful for debugging. |
| */ |
| |
| /* |
| * Mininum / Maximum order of slab pages. This influences locking overhead |
| * and slab fragmentation. A higher order reduces the number of partial slabs |
| * and increases the number of allocations possible without having to |
| * take the list_lock. |
| */ |
| static int slub_min_order; |
| static int slub_max_order = DEFAULT_MAX_ORDER; |
| |
| /* |
| * Minimum number of objects per slab. This is necessary in order to |
| * reduce locking overhead. Similar to the queue size in SLAB. |
| */ |
| static int slub_min_objects = DEFAULT_MIN_OBJECTS; |
| |
| /* |
| * Merge control. If this is set then no merging of slab caches will occur. |
| */ |
| static int slub_nomerge; |
| |
| /* |
| * Debug settings: |
| */ |
| static int slub_debug; |
| |
| static char *slub_debug_slabs; |
| |
| /* |
| * Calculate the order of allocation given an slab object size. |
| * |
| * The order of allocation has significant impact on other elements |
| * of the system. Generally order 0 allocations should be preferred |
| * since they do not cause fragmentation in the page allocator. Larger |
| * objects may have problems with order 0 because there may be too much |
| * space left unused in a slab. We go to a higher order if more than 1/8th |
| * of the slab would be wasted. |
| * |
| * In order to reach satisfactory performance we must ensure that |
| * a minimum number of objects is in one slab. Otherwise we may |
| * generate too much activity on the partial lists. This is less a |
| * concern for large slabs though. slub_max_order specifies the order |
| * where we begin to stop considering the number of objects in a slab. |
| * |
| * Higher order allocations also allow the placement of more objects |
| * in a slab and thereby reduce object handling overhead. If the user |
| * has requested a higher mininum order then we start with that one |
| * instead of zero. |
| */ |
| static int calculate_order(int size) |
| { |
| int order; |
| int rem; |
| |
| for (order = max(slub_min_order, fls(size - 1) - PAGE_SHIFT); |
| order < MAX_ORDER; order++) { |
| unsigned long slab_size = PAGE_SIZE << order; |
| |
| if (slub_max_order > order && |
| slab_size < slub_min_objects * size) |
| continue; |
| |
| if (slab_size < size) |
| continue; |
| |
| rem = slab_size % size; |
| |
| if (rem <= (PAGE_SIZE << order) / 8) |
| break; |
| |
| } |
| if (order >= MAX_ORDER) |
| return -E2BIG; |
| return order; |
| } |
| |
| /* |
| * Function to figure out which alignment to use from the |
| * various ways of specifying it. |
| */ |
| static unsigned long calculate_alignment(unsigned long flags, |
| unsigned long align, unsigned long size) |
| { |
| /* |
| * If the user wants hardware cache aligned objects then |
| * follow that suggestion if the object is sufficiently |
| * large. |
| * |
| * The hardware cache alignment cannot override the |
| * specified alignment though. If that is greater |
| * then use it. |
| */ |
| if ((flags & (SLAB_MUST_HWCACHE_ALIGN | SLAB_HWCACHE_ALIGN)) && |
| size > L1_CACHE_BYTES / 2) |
| return max_t(unsigned long, align, L1_CACHE_BYTES); |
| |
| if (align < ARCH_SLAB_MINALIGN) |
| return ARCH_SLAB_MINALIGN; |
| |
| return ALIGN(align, sizeof(void *)); |
| } |
| |
| static void init_kmem_cache_node(struct kmem_cache_node *n) |
| { |
| n->nr_partial = 0; |
| atomic_long_set(&n->nr_slabs, 0); |
| spin_lock_init(&n->list_lock); |
| INIT_LIST_HEAD(&n->partial); |
| } |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * No kmalloc_node yet so do it by hand. We know that this is the first |
| * slab on the node for this slabcache. There are no concurrent accesses |
| * possible. |
| * |
| * Note that this function only works on the kmalloc_node_cache |
| * when allocating for the kmalloc_node_cache. |
| */ |
| static struct kmem_cache_node * __init early_kmem_cache_node_alloc(gfp_t gfpflags, |
| int node) |
| { |
| struct page *page; |
| struct kmem_cache_node *n; |
| |
| BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node)); |
| |
| page = new_slab(kmalloc_caches, gfpflags | GFP_THISNODE, node); |
| /* new_slab() disables interupts */ |
| local_irq_enable(); |
| |
| BUG_ON(!page); |
| n = page->freelist; |
| BUG_ON(!n); |
| page->freelist = get_freepointer(kmalloc_caches, n); |
| page->inuse++; |
| kmalloc_caches->node[node] = n; |
| init_object(kmalloc_caches, n, 1); |
| init_kmem_cache_node(n); |
| atomic_long_inc(&n->nr_slabs); |
| add_partial(kmalloc_caches, page); |
| return n; |
| } |
| |
| static void free_kmem_cache_nodes(struct kmem_cache *s) |
| { |
| int node; |
| |
| for_each_online_node(node) { |
| struct kmem_cache_node *n = s->node[node]; |
| if (n && n != &s->local_node) |
| kmem_cache_free(kmalloc_caches, n); |
| s->node[node] = NULL; |
| } |
| } |
| |
| static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) |
| { |
| int node; |
| int local_node; |
| |
| if (slab_state >= UP) |
| local_node = page_to_nid(virt_to_page(s)); |
| else |
| local_node = 0; |
| |
| for_each_online_node(node) { |
| struct kmem_cache_node *n; |
| |
| if (local_node == node) |
| n = &s->local_node; |
| else { |
| if (slab_state == DOWN) { |
| n = early_kmem_cache_node_alloc(gfpflags, |
| node); |
| continue; |
| } |
| n = kmem_cache_alloc_node(kmalloc_caches, |
| gfpflags, node); |
| |
| if (!n) { |
| free_kmem_cache_nodes(s); |
| return 0; |
| } |
| |
| } |
| s->node[node] = n; |
| init_kmem_cache_node(n); |
| } |
| return 1; |
| } |
| #else |
| static void free_kmem_cache_nodes(struct kmem_cache *s) |
| { |
| } |
| |
| static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) |
| { |
| init_kmem_cache_node(&s->local_node); |
| return 1; |
| } |
| #endif |
| |
| /* |
| * calculate_sizes() determines the order and the distribution of data within |
| * a slab object. |
| */ |
| static int calculate_sizes(struct kmem_cache *s) |
| { |
| unsigned long flags = s->flags; |
| unsigned long size = s->objsize; |
| unsigned long align = s->align; |
| |
| /* |
| * Determine if we can poison the object itself. If the user of |
| * the slab may touch the object after free or before allocation |
| * then we should never poison the object itself. |
| */ |
| if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) && |
| !s->ctor && !s->dtor) |
| s->flags |= __OBJECT_POISON; |
| else |
| s->flags &= ~__OBJECT_POISON; |
| |
| /* |
| * Round up object size to the next word boundary. We can only |
| * place the free pointer at word boundaries and this determines |
| * the possible location of the free pointer. |
| */ |
| size = ALIGN(size, sizeof(void *)); |
| |
| /* |
| * If we are redzoning then check if there is some space between the |
| * end of the object and the free pointer. If not then add an |
| * additional word, so that we can establish a redzone between |
| * the object and the freepointer to be able to check for overwrites. |
| */ |
| if ((flags & SLAB_RED_ZONE) && size == s->objsize) |
| size += sizeof(void *); |
| |
| /* |
| * With that we have determined how much of the slab is in actual |
| * use by the object. This is the potential offset to the free |
| * pointer. |
| */ |
| s->inuse = size; |
| |
| if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) || |
| s->ctor || s->dtor)) { |
| /* |
| * Relocate free pointer after the object if it is not |
| * permitted to overwrite the first word of the object on |
| * kmem_cache_free. |
| * |
| * This is the case if we do RCU, have a constructor or |
| * destructor or are poisoning the objects. |
| */ |
| s->offset = size; |
| size += sizeof(void *); |
| } |
| |
| if (flags & SLAB_STORE_USER) |
| /* |
| * Need to store information about allocs and frees after |
| * the object. |
| */ |
| size += 2 * sizeof(struct track); |
| |
| if (flags & DEBUG_DEFAULT_FLAGS) |
| /* |
| * Add some empty padding so that we can catch |
| * overwrites from earlier objects rather than let |
| * tracking information or the free pointer be |
| * corrupted if an user writes before the start |
| * of the object. |
| */ |
| size += sizeof(void *); |
| /* |
| * Determine the alignment based on various parameters that the |
| * user specified (this is unecessarily complex due to the attempt |
| * to be compatible with SLAB. Should be cleaned up some day). |
| */ |
| align = calculate_alignment(flags, align, s->objsize); |
| |
| /* |
| * SLUB stores one object immediately after another beginning from |
| * offset 0. In order to align the objects we have to simply size |
| * each object to conform to the alignment. |
| */ |
| size = ALIGN(size, align); |
| s->size = size; |
| |
| s->order = calculate_order(size); |
| if (s->order < 0) |
| return 0; |
| |
| /* |
| * Determine the number of objects per slab |
| */ |
| s->objects = (PAGE_SIZE << s->order) / size; |
| |
| /* |
| * Verify that the number of objects is within permitted limits. |
| * The page->inuse field is only 16 bit wide! So we cannot have |
| * more than 64k objects per slab. |
| */ |
| if (!s->objects || s->objects > 65535) |
| return 0; |
| return 1; |
| |
| } |
| |
| static int __init finish_bootstrap(void) |
| { |
| struct list_head *h; |
| int err; |
| |
| slab_state = SYSFS; |
| |
| list_for_each(h, &slab_caches) { |
| struct kmem_cache *s = |
| container_of(h, struct kmem_cache, list); |
| |
| err = sysfs_slab_add(s); |
| BUG_ON(err); |
| } |
| return 0; |
| } |
| |
| static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, |
| 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)) |
| { |
| memset(s, 0, kmem_size); |
| s->name = name; |
| s->ctor = ctor; |
| s->dtor = dtor; |
| s->objsize = size; |
| s->flags = flags; |
| s->align = align; |
| |
| BUG_ON(flags & SLUB_UNIMPLEMENTED); |
| |
| /* |
| * The page->offset field is only 16 bit wide. This is an offset |
| * in units of words from the beginning of an object. If the slab |
| * size is bigger then we cannot move the free pointer behind the |
| * object anymore. |
| * |
| * On 32 bit platforms the limit is 256k. On 64bit platforms |
| * the limit is 512k. |
| * |
| * Debugging or ctor/dtors may create a need to move the free |
| * pointer. Fail if this happens. |
| */ |
| if (s->size >= 65535 * sizeof(void *)) { |
| BUG_ON(flags & (SLAB_RED_ZONE | SLAB_POISON | |
| SLAB_STORE_USER | SLAB_DESTROY_BY_RCU)); |
| BUG_ON(ctor || dtor); |
| } |
| else |
| /* |
| * Enable debugging if selected on the kernel commandline. |
| */ |
| if (slub_debug && (!slub_debug_slabs || |
| strncmp(slub_debug_slabs, name, |
| strlen(slub_debug_slabs)) == 0)) |
| s->flags |= slub_debug; |
| |
| if (!calculate_sizes(s)) |
| goto error; |
| |
| s->refcount = 1; |
| #ifdef CONFIG_NUMA |
| s->defrag_ratio = 100; |
| #endif |
| |
| if (init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA)) |
| return 1; |
| error: |
| if (flags & SLAB_PANIC) |
| panic("Cannot create slab %s size=%lu realsize=%u " |
| "order=%u offset=%u flags=%lx\n", |
| s->name, (unsigned long)size, s->size, s->order, |
| s->offset, flags); |
| return 0; |
| } |
| EXPORT_SYMBOL(kmem_cache_open); |
| |
| /* |
| * Check if a given pointer is valid |
| */ |
| int kmem_ptr_validate(struct kmem_cache *s, const void *object) |
| { |
| struct page * page; |
| void *addr; |
| |
| page = get_object_page(object); |
| |
| if (!page || s != page->slab) |
| /* No slab or wrong slab */ |
| return 0; |
| |
| addr = page_address(page); |
| if (object < addr || object >= addr + s->objects * s->size) |
| /* Out of bounds */ |
| return 0; |
| |
| if ((object - addr) % s->size) |
| /* Improperly aligned */ |
| return 0; |
| |
| /* |
| * We could also check if the object is on the slabs freelist. |
| * But this would be too expensive and it seems that the main |
| * purpose of kmem_ptr_valid is to check if the object belongs |
| * to a certain slab. |
| */ |
| return 1; |
| } |
| EXPORT_SYMBOL(kmem_ptr_validate); |
| |
| /* |
| * Determine the size of a slab object |
| */ |
| unsigned int kmem_cache_size(struct kmem_cache *s) |
| { |
| return s->objsize; |
| } |
| EXPORT_SYMBOL(kmem_cache_size); |
| |
| const char *kmem_cache_name(struct kmem_cache *s) |
| { |
| return s->name; |
| } |
| EXPORT_SYMBOL(kmem_cache_name); |
| |
| /* |
| * Attempt to free all slabs on a node |
| */ |
| static int free_list(struct kmem_cache *s, struct kmem_cache_node *n, |
| struct list_head *list) |
| { |
| int slabs_inuse = 0; |
| unsigned long flags; |
| struct page *page, *h; |
| |
| spin_lock_irqsave(&n->list_lock, flags); |
| list_for_each_entry_safe(page, h, list, lru) |
| if (!page->inuse) { |
| list_del(&page->lru); |
| discard_slab(s, page); |
| } else |
| slabs_inuse++; |
| spin_unlock_irqrestore(&n->list_lock, flags); |
| return slabs_inuse; |
| } |
| |
| /* |
| * Release all resources used by slab cache |
| */ |
| static int kmem_cache_close(struct kmem_cache *s) |
| { |
| int node; |
| |
| flush_all(s); |
| |
| /* Attempt to free all objects */ |
| for_each_online_node(node) { |
| struct kmem_cache_node *n = get_node(s, node); |
| |
| free_list(s, n, &n->partial); |
| if (atomic_long_read(&n->nr_slabs)) |
| return 1; |
| } |
| free_kmem_cache_nodes(s); |
| return 0; |
| } |
| |
| /* |
| * Close a cache and release the kmem_cache structure |
| * (must be used for caches created using kmem_cache_create) |
| */ |
| void kmem_cache_destroy(struct kmem_cache *s) |
| { |
| down_write(&slub_lock); |
| s->refcount--; |
| if (!s->refcount) { |
| list_del(&s->list); |
| if (kmem_cache_close(s)) |
| WARN_ON(1); |
| sysfs_slab_remove(s); |
| kfree(s); |
| } |
| up_write(&slub_lock); |
| } |
| EXPORT_SYMBOL(kmem_cache_destroy); |
| |
| /******************************************************************** |
| * Kmalloc subsystem |
| *******************************************************************/ |
| |
| struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1] __cacheline_aligned; |
| EXPORT_SYMBOL(kmalloc_caches); |
| |
| #ifdef CONFIG_ZONE_DMA |
| static struct kmem_cache *kmalloc_caches_dma[KMALLOC_SHIFT_HIGH + 1]; |
| #endif |
| |
| static int __init setup_slub_min_order(char *str) |
| { |
| get_option (&str, &slub_min_order); |
| |
| return 1; |
| } |
| |
| __setup("slub_min_order=", setup_slub_min_order); |
| |
| static int __init setup_slub_max_order(char *str) |
| { |
| get_option (&str, &slub_max_order); |
| |
| return 1; |
| } |
| |
| __setup("slub_max_order=", setup_slub_max_order); |
| |
| static int __init setup_slub_min_objects(char *str) |
| { |
| get_option (&str, &slub_min_objects); |
| |
| return 1; |
| } |
| |
| __setup("slub_min_objects=", setup_slub_min_objects); |
| |
| static int __init setup_slub_nomerge(char *str) |
| { |
| slub_nomerge = 1; |
| return 1; |
| } |
| |
| __setup("slub_nomerge", setup_slub_nomerge); |
| |
| static int __init setup_slub_debug(char *str) |
| { |
| if (!str || *str != '=') |
| slub_debug = DEBUG_DEFAULT_FLAGS; |
| else { |
| str++; |
| if (*str == 0 || *str == ',') |
| slub_debug = DEBUG_DEFAULT_FLAGS; |
| else |
| for( ;*str && *str != ','; str++) |
| switch (*str) { |
| case 'f' : case 'F' : |
| slub_debug |= SLAB_DEBUG_FREE; |
| break; |
| case 'z' : case 'Z' : |
| slub_debug |= SLAB_RED_ZONE; |
| break; |
| case 'p' : case 'P' : |
| slub_debug |= SLAB_POISON; |
| break; |
| case 'u' : case 'U' : |
| slub_debug |= SLAB_STORE_USER; |
| break; |
| case 't' : case 'T' : |
| slub_debug |= SLAB_TRACE; |
| break; |
| default: |
| printk(KERN_ERR "slub_debug option '%c' " |
| "unknown. skipped\n",*str); |
| } |
| } |
| |
| if (*str == ',') |
| slub_debug_slabs = str + 1; |
| return 1; |
| } |
| |
| __setup("slub_debug", setup_slub_debug); |
| |
| static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s, |
| const char *name, int size, gfp_t gfp_flags) |
| { |
| unsigned int flags = 0; |
| |
| if (gfp_flags & SLUB_DMA) |
| flags = SLAB_CACHE_DMA; |
| |
| down_write(&slub_lock); |
| if (!kmem_cache_open(s, gfp_flags, name, size, ARCH_KMALLOC_MINALIGN, |
| flags, NULL, NULL)) |
| goto panic; |
| |
| list_add(&s->list, &slab_caches); |
| up_write(&slub_lock); |
| if (sysfs_slab_add(s)) |
| goto panic; |
| return s; |
| |
| panic: |
| panic("Creation of kmalloc slab %s size=%d failed.\n", name, size); |
| } |
| |
| static struct kmem_cache *get_slab(size_t size, gfp_t flags) |
| { |
| int index = kmalloc_index(size); |
| |
| if (!size) |
| return NULL; |
| |
| /* Allocation too large? */ |
| BUG_ON(index < 0); |
| |
| #ifdef CONFIG_ZONE_DMA |
| if ((flags & SLUB_DMA)) { |
| struct kmem_cache *s; |
| struct kmem_cache *x; |
| char *text; |
| size_t realsize; |
| |
| s = kmalloc_caches_dma[index]; |
| if (s) |
| return s; |
| |
| /* Dynamically create dma cache */ |
| x = kmalloc(kmem_size, flags & ~SLUB_DMA); |
| if (!x) |
| panic("Unable to allocate memory for dma cache\n"); |
| |
| if (index <= KMALLOC_SHIFT_HIGH) |
| realsize = 1 << index; |
| else { |
| if (index == 1) |
| realsize = 96; |
| else |
| realsize = 192; |
| } |
| |
| text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", |
| (unsigned int)realsize); |
| s = create_kmalloc_cache(x, text, realsize, flags); |
| kmalloc_caches_dma[index] = s; |
| return s; |
| } |
| #endif |
| return &kmalloc_caches[index]; |
| } |
| |
| void *__kmalloc(size_t size, gfp_t flags) |
| { |
| struct kmem_cache *s = get_slab(size, flags); |
| |
| if (s) |
| return kmem_cache_alloc(s, flags); |
| return NULL; |
| } |
| EXPORT_SYMBOL(__kmalloc); |
| |
| #ifdef CONFIG_NUMA |
| void *__kmalloc_node(size_t size, gfp_t flags, int node) |
| { |
| struct kmem_cache *s = get_slab(size, flags); |
| |
| if (s) |
| return kmem_cache_alloc_node(s, flags, node); |
| return NULL; |
| } |
| EXPORT_SYMBOL(__kmalloc_node); |
| #endif |
| |
| size_t ksize(const void *object) |
| { |
| struct page *page = get_object_page(object); |
| struct kmem_cache *s; |
| |
| BUG_ON(!page); |
| s = page->slab; |
| BUG_ON(!s); |
| |
| /* |
| * Debugging requires use of the padding between object |
| * and whatever may come after it. |
| */ |
| if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) |
| return s->objsize; |
| |
| /* |
| * If we have the need to store the freelist pointer |
| * back there or track user information then we can |
| * only use the space before that information. |
| */ |
| if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER)) |
| return s->inuse; |
| |
| /* |
| * Else we can use all the padding etc for the allocation |
| */ |
| return s->size; |
| } |
| EXPORT_SYMBOL(ksize); |
| |
| void kfree(const void *x) |
| { |
| struct kmem_cache *s; |
| struct page *page; |
| |
| if (!x) |
| return; |
| |
| page = virt_to_page(x); |
| |
| if (unlikely(PageCompound(page))) |
| page = page->first_page; |
| |
| s = page->slab; |
| |
| if (unlikely(PageError(page) && (s->flags & SLAB_STORE_USER))) |
| set_tracking(s, (void *)x, TRACK_FREE); |
| slab_free(s, page, (void *)x); |
| } |
| EXPORT_SYMBOL(kfree); |
| |
| /** |
| * krealloc - reallocate memory. The contents will remain unchanged. |
| * |
| * @p: object to reallocate memory for. |
| * @new_size: how many bytes of memory are required. |
| * @flags: the type of memory to allocate. |
| * |
| * The contents of the object pointed to are preserved up to the |
| * lesser of the new and old sizes. If @p is %NULL, krealloc() |
| * behaves exactly like kmalloc(). If @size is 0 and @p is not a |
| * %NULL pointer, the object pointed to is freed. |
| */ |
| void *krealloc(const void *p, size_t new_size, gfp_t flags) |
| { |
| struct kmem_cache *new_cache; |
| void *ret; |
| struct page *page; |
| |
| if (unlikely(!p)) |
| return kmalloc(new_size, flags); |
| |
| if (unlikely(!new_size)) { |
| kfree(p); |
| return NULL; |
| } |
| |
| page = virt_to_page(p); |
| |
| if (unlikely(PageCompound(page))) |
| page = page->first_page; |
| |
| new_cache = get_slab(new_size, flags); |
| |
| /* |
| * If new size fits in the current cache, bail out. |
| */ |
| if (likely(page->slab == new_cache)) |
| return (void *)p; |
| |
| ret = kmalloc(new_size, flags); |
| if (ret) { |
| memcpy(ret, p, min(new_size, ksize(p))); |
| kfree(p); |
| } |
| return ret; |
| } |
| EXPORT_SYMBOL(krealloc); |
| |
| /******************************************************************** |
| * Basic setup of slabs |
| *******************************************************************/ |
| |
| void __init kmem_cache_init(void) |
| { |
| int i; |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * Must first have the slab cache available for the allocations of the |
| * struct kmalloc_cache_node's. There is special bootstrap code in |
| * kmem_cache_open for slab_state == DOWN. |
| */ |
| create_kmalloc_cache(&kmalloc_caches[0], "kmem_cache_node", |
| sizeof(struct kmem_cache_node), GFP_KERNEL); |
| #endif |
| |
| /* Able to allocate the per node structures */ |
| slab_state = PARTIAL; |
| |
| /* Caches that are not of the two-to-the-power-of size */ |
| create_kmalloc_cache(&kmalloc_caches[1], |
| "kmalloc-96", 96, GFP_KERNEL); |
| create_kmalloc_cache(&kmalloc_caches[2], |
| "kmalloc-192", 192, GFP_KERNEL); |
| |
| for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) |
| create_kmalloc_cache(&kmalloc_caches[i], |
| "kmalloc", 1 << i, GFP_KERNEL); |
| |
| slab_state = UP; |
| |
| /* Provide the correct kmalloc names now that the caches are up */ |
| for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) |
| kmalloc_caches[i]. name = |
| kasprintf(GFP_KERNEL, "kmalloc-%d", 1 << i); |
| |
| #ifdef CONFIG_SMP |
| register_cpu_notifier(&slab_notifier); |
| #endif |
| |
| if (nr_cpu_ids) /* Remove when nr_cpu_ids is fixed upstream ! */ |
| kmem_size = offsetof(struct kmem_cache, cpu_slab) |
| + nr_cpu_ids * sizeof(struct page *); |
| |
| printk(KERN_INFO "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d," |
| " Processors=%d, Nodes=%d\n", |
| KMALLOC_SHIFT_HIGH, L1_CACHE_BYTES, |
| slub_min_order, slub_max_order, slub_min_objects, |
| nr_cpu_ids, nr_node_ids); |
| } |
| |
| /* |
| * Find a mergeable slab cache |
| */ |
| static int slab_unmergeable(struct kmem_cache *s) |
| { |
| if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE)) |
| return 1; |
| |
| if (s->ctor || s->dtor) |
| return 1; |
| |
| return 0; |
| } |
| |
| static struct kmem_cache *find_mergeable(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)) |
| { |
| struct list_head *h; |
| |
| if (slub_nomerge || (flags & SLUB_NEVER_MERGE)) |
| return NULL; |
| |
| if (ctor || dtor) |
| return NULL; |
| |
| size = ALIGN(size, sizeof(void *)); |
| align = calculate_alignment(flags, align, size); |
| size = ALIGN(size, align); |
| |
| list_for_each(h, &slab_caches) { |
| struct kmem_cache *s = |
| container_of(h, struct kmem_cache, list); |
| |
| if (slab_unmergeable(s)) |
| continue; |
| |
| if (size > s->size) |
| continue; |
| |
| if (((flags | slub_debug) & SLUB_MERGE_SAME) != |
| (s->flags & SLUB_MERGE_SAME)) |
| continue; |
| /* |
| * Check if alignment is compatible. |
| * Courtesy of Adrian Drzewiecki |
| */ |
| if ((s->size & ~(align -1)) != s->size) |
| continue; |
| |
| if (s->size - size >= sizeof(void *)) |
| continue; |
| |
| return s; |
| } |
| return NULL; |
| } |
| |
| 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)) |
| { |
| struct kmem_cache *s; |
| |
| down_write(&slub_lock); |
| s = find_mergeable(size, align, flags, dtor, ctor); |
| if (s) { |
| s->refcount++; |
| /* |
| * Adjust the object sizes so that we clear |
| * the complete object on kzalloc. |
| */ |
| s->objsize = max(s->objsize, (int)size); |
| s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *))); |
| if (sysfs_slab_alias(s, name)) |
| goto err; |
| } else { |
| s = kmalloc(kmem_size, GFP_KERNEL); |
| if (s && kmem_cache_open(s, GFP_KERNEL, name, |
| size, align, flags, ctor, dtor)) { |
| if (sysfs_slab_add(s)) { |
| kfree(s); |
| goto err; |
| } |
| list_add(&s->list, &slab_caches); |
| } else |
| kfree(s); |
| } |
| up_write(&slub_lock); |
| return s; |
| |
| err: |
| up_write(&slub_lock); |
| if (flags & SLAB_PANIC) |
| panic("Cannot create slabcache %s\n", name); |
| else |
| s = NULL; |
| return s; |
| } |
| EXPORT_SYMBOL(kmem_cache_create); |
| |
| void *kmem_cache_zalloc(struct kmem_cache *s, gfp_t flags) |
| { |
| void *x; |
| |
| x = kmem_cache_alloc(s, flags); |
| if (x) |
| memset(x, 0, s->objsize); |
| return x; |
| } |
| EXPORT_SYMBOL(kmem_cache_zalloc); |
| |
| #ifdef CONFIG_SMP |
| static void for_all_slabs(void (*func)(struct kmem_cache *, int), int cpu) |
| { |
| struct list_head *h; |
| |
| down_read(&slub_lock); |
| list_for_each(h, &slab_caches) { |
| struct kmem_cache *s = |
| container_of(h, struct kmem_cache, list); |
| |
| func(s, cpu); |
| } |
| up_read(&slub_lock); |
| } |
| |
| /* |
| * Use the cpu notifier to insure that the slab are flushed |
| * when necessary. |
| */ |
| static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb, |
| unsigned long action, void *hcpu) |
| { |
| long cpu = (long)hcpu; |
| |
| switch (action) { |
| case CPU_UP_CANCELED: |
| case CPU_DEAD: |
| for_all_slabs(__flush_cpu_slab, cpu); |
| break; |
| default: |
| break; |
| } |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block __cpuinitdata slab_notifier = |
| { &slab_cpuup_callback, NULL, 0 }; |
| |
| #endif |
| |
| /*************************************************************** |
| * Compatiblility definitions |
| **************************************************************/ |
| |
| int kmem_cache_shrink(struct kmem_cache *s) |
| { |
| flush_all(s); |
| return 0; |
| } |
| EXPORT_SYMBOL(kmem_cache_shrink); |
| |
| #ifdef CONFIG_NUMA |
| |
| /***************************************************************** |
| * Generic reaper used to support the page allocator |
| * (the cpu slabs are reaped by a per slab workqueue). |
| * |
| * Maybe move this to the page allocator? |
| ****************************************************************/ |
| |
| 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); |
| |
| __get_cpu_var(reap_node) = node; |
| } |
| |
| static void next_reap_node(void) |
| { |
| int node = __get_cpu_var(reap_node); |
| |
| /* |
| * Also drain per cpu pages on remote zones |
| */ |
| if (node != numa_node_id()) |
| drain_node_pages(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 |
| |
| #define REAPTIMEOUT_CPUC (2*HZ) |
| |
| #ifdef CONFIG_SMP |
| static DEFINE_PER_CPU(struct delayed_work, reap_work); |
| |
| static void cache_reap(struct work_struct *unused) |
| { |
| next_reap_node(); |
| refresh_cpu_vm_stats(smp_processor_id()); |
| schedule_delayed_work(&__get_cpu_var(reap_work), |
| REAPTIMEOUT_CPUC); |
| } |
| |
| static void __devinit 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, HZ + 3 * cpu); |
| } |
| } |
| |
| static int __init cpucache_init(void) |
| { |
| int cpu; |
| |
| /* |
| * Register the timers that drain pcp pages and update vm statistics |
| */ |
| for_each_online_cpu(cpu) |
| start_cpu_timer(cpu); |
| return 0; |
| } |
| __initcall(cpucache_init); |
| #endif |
| |
| #ifdef SLUB_RESILIENCY_TEST |
| static unsigned long validate_slab_cache(struct kmem_cache *s); |
| |
| static void resiliency_test(void) |
| { |
| u8 *p; |
| |
| printk(KERN_ERR "SLUB resiliency testing\n"); |
| printk(KERN_ERR "-----------------------\n"); |
| printk(KERN_ERR "A. Corruption after allocation\n"); |
| |
| p = kzalloc(16, GFP_KERNEL); |
| p[16] = 0x12; |
| printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer" |
| " 0x12->0x%p\n\n", p + 16); |
| |
| validate_slab_cache(kmalloc_caches + 4); |
| |
| /* Hmmm... The next two are dangerous */ |
| p = kzalloc(32, GFP_KERNEL); |
| p[32 + sizeof(void *)] = 0x34; |
| printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab" |
| " 0x34 -> -0x%p\n", p); |
| printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n"); |
| |
| validate_slab_cache(kmalloc_caches + 5); |
| p = kzalloc(64, GFP_KERNEL); |
| p += 64 + (get_cycles() & 0xff) * sizeof(void *); |
| *p = 0x56; |
| printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n", |
| p); |
| printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n"); |
| validate_slab_cache(kmalloc_caches + 6); |
| |
| printk(KERN_ERR "\nB. Corruption after free\n"); |
| p = kzalloc(128, GFP_KERNEL); |
| kfree(p); |
| *p = 0x78; |
| printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p); |
| validate_slab_cache(kmalloc_caches + 7); |
| |
| p = kzalloc(256, GFP_KERNEL); |
| kfree(p); |
| p[50] = 0x9a; |
| printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p); |
| validate_slab_cache(kmalloc_caches + 8); |
| |
| p = kzalloc(512, GFP_KERNEL); |
| kfree(p); |
| p[512] = 0xab; |
| printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p); |
| validate_slab_cache(kmalloc_caches + 9); |
| } |
| #else |
| static void resiliency_test(void) {}; |
| #endif |
| |
| /* |
| * These are not as efficient as kmalloc for the non debug case. |
| * We do not have the page struct available so we have to touch one |
| * cacheline in struct kmem_cache to check slab flags. |
| */ |
| void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller) |
| { |
| struct kmem_cache *s = get_slab(size, gfpflags); |
| void *object; |
| |
| if (!s) |
| return NULL; |
| |
| object = kmem_cache_alloc(s, gfpflags); |
| |
| if (object && (s->flags & SLAB_STORE_USER)) |
| set_track(s, object, TRACK_ALLOC, caller); |
| |
| return object; |
| } |
| |
| void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, |
| int node, void *caller) |
| { |
| struct kmem_cache *s = get_slab(size, gfpflags); |
| void *object; |
| |
| if (!s) |
| return NULL; |
| |
| object = kmem_cache_alloc_node(s, gfpflags, node); |
| |
| if (object && (s->flags & SLAB_STORE_USER)) |
| set_track(s, object, TRACK_ALLOC, caller); |
| |
| return object; |
| } |
| |
| #ifdef CONFIG_SYSFS |
| |
| static unsigned long count_partial(struct kmem_cache_node *n) |
| { |
| unsigned long flags; |
| unsigned long x = 0; |
| struct page *page; |
| |
| spin_lock_irqsave(&n->list_lock, flags); |
| list_for_each_entry(page, &n->partial, lru) |
| x += page->inuse; |
| spin_unlock_irqrestore(&n->list_lock, flags); |
| return x; |
| } |
| |
| enum slab_stat_type { |
| SL_FULL, |
| SL_PARTIAL, |
| SL_CPU, |
| SL_OBJECTS |
| }; |
| |
| #define SO_FULL (1 << SL_FULL) |
| #define SO_PARTIAL (1 << SL_PARTIAL) |
| #define SO_CPU (1 << SL_CPU) |
| #define SO_OBJECTS (1 << SL_OBJECTS) |
| |
| static unsigned long slab_objects(struct kmem_cache *s, |
| char *buf, unsigned long flags) |
| { |
| unsigned long total = 0; |
| int cpu; |
| int node; |
| int x; |
| unsigned long *nodes; |
| unsigned long *per_cpu; |
| |
| nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL); |
| per_cpu = nodes + nr_node_ids; |
| |
| for_each_possible_cpu(cpu) { |
| struct page *page = s->cpu_slab[cpu]; |
| int node; |
| |
| if (page) { |
| node = page_to_nid(page); |
| if (flags & SO_CPU) { |
| int x = 0; |
| |
| if (flags & SO_OBJECTS) |
| x = page->inuse; |
| else |
| x = 1; |
| total += x; |
| nodes[node] += x; |
| } |
| per_cpu[node]++; |
| } |
| } |
| |
| for_each_online_node(node) { |
| struct kmem_cache_node *n = get_node(s, node); |
| |
| if (flags & SO_PARTIAL) { |
| if (flags & SO_OBJECTS) |
| x = count_partial(n); |
| else |
| x = n->nr_partial; |
| total += x; |
| nodes[node] += x; |
| } |
| |
| if (flags & SO_FULL) { |
| int full_slabs = atomic_read(&n->nr_slabs) |
| - per_cpu[node] |
| - n->nr_partial; |
| |
| if (flags & SO_OBJECTS) |
| x = full_slabs * s->objects; |
| else |
| x = full_slabs; |
| total += x; |
| nodes[node] += x; |
| } |
| } |
| |
| x = sprintf(buf, "%lu", total); |
| #ifdef CONFIG_NUMA |
| for_each_online_node(node) |
| if (nodes[node]) |
| x += sprintf(buf + x, " N%d=%lu", |
| node, nodes[node]); |
| #endif |
| kfree(nodes); |
| return x + sprintf(buf + x, "\n"); |
| } |
| |
| static int any_slab_objects(struct kmem_cache *s) |
| { |
| int node; |
| int cpu; |
| |
| for_each_possible_cpu(cpu) |
| if (s->cpu_slab[cpu]) |
| return 1; |
| |
| for_each_node(node) { |
| struct kmem_cache_node *n = get_node(s, node); |
| |
| if (n->nr_partial || atomic_read(&n->nr_slabs)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| #define to_slab_attr(n) container_of(n, struct slab_attribute, attr) |
| #define to_slab(n) container_of(n, struct kmem_cache, kobj); |
| |
| struct slab_attribute { |
| struct attribute attr; |
| ssize_t (*show)(struct kmem_cache *s, char *buf); |
| ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); |
| }; |
| |
| #define SLAB_ATTR_RO(_name) \ |
| static struct slab_attribute _name##_attr = __ATTR_RO(_name) |
| |
| #define SLAB_ATTR(_name) \ |
| static struct slab_attribute _name##_attr = \ |
| __ATTR(_name, 0644, _name##_show, _name##_store) |
| |
| |
| static ssize_t slab_size_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->size); |
| } |
| SLAB_ATTR_RO(slab_size); |
| |
| static ssize_t align_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->align); |
| } |
| SLAB_ATTR_RO(align); |
| |
| static ssize_t object_size_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->objsize); |
| } |
| SLAB_ATTR_RO(object_size); |
| |
| static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->objects); |
| } |
| SLAB_ATTR_RO(objs_per_slab); |
| |
| static ssize_t order_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->order); |
| } |
| SLAB_ATTR_RO(order); |
| |
| static ssize_t ctor_show(struct kmem_cache *s, char *buf) |
| { |
| if (s->ctor) { |
| int n = sprint_symbol(buf, (unsigned long)s->ctor); |
| |
| return n + sprintf(buf + n, "\n"); |
| } |
| return 0; |
| } |
| SLAB_ATTR_RO(ctor); |
| |
| static ssize_t dtor_show(struct kmem_cache *s, char *buf) |
| { |
| if (s->dtor) { |
| int n = sprint_symbol(buf, (unsigned long)s->dtor); |
| |
| return n + sprintf(buf + n, "\n"); |
| } |
| return 0; |
| } |
| SLAB_ATTR_RO(dtor); |
| |
| static ssize_t aliases_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->refcount - 1); |
| } |
| SLAB_ATTR_RO(aliases); |
| |
| static ssize_t slabs_show(struct kmem_cache *s, char *buf) |
| { |
| return slab_objects(s, buf, SO_FULL|SO_PARTIAL|SO_CPU); |
| } |
| SLAB_ATTR_RO(slabs); |
| |
| static ssize_t partial_show(struct kmem_cache *s, char *buf) |
| { |
| return slab_objects(s, buf, SO_PARTIAL); |
| } |
| SLAB_ATTR_RO(partial); |
| |
| static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) |
| { |
| return slab_objects(s, buf, SO_CPU); |
| } |
| SLAB_ATTR_RO(cpu_slabs); |
| |
| static ssize_t objects_show(struct kmem_cache *s, char *buf) |
| { |
| return slab_objects(s, buf, SO_FULL|SO_PARTIAL|SO_CPU|SO_OBJECTS); |
| } |
| SLAB_ATTR_RO(objects); |
| |
| static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE)); |
| } |
| |
| static ssize_t sanity_checks_store(struct kmem_cache *s, |
| const char *buf, size_t length) |
| { |
| s->flags &= ~SLAB_DEBUG_FREE; |
| if (buf[0] == '1') |
| s->flags |= SLAB_DEBUG_FREE; |
| return length; |
| } |
| SLAB_ATTR(sanity_checks); |
| |
| static ssize_t trace_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE)); |
| } |
| |
| static ssize_t trace_store(struct kmem_cache *s, const char *buf, |
| size_t length) |
| { |
| s->flags &= ~SLAB_TRACE; |
| if (buf[0] == '1') |
| s->flags |= SLAB_TRACE; |
| return length; |
| } |
| SLAB_ATTR(trace); |
| |
| static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); |
| } |
| |
| static ssize_t reclaim_account_store(struct kmem_cache *s, |
| const char *buf, size_t length) |
| { |
| s->flags &= ~SLAB_RECLAIM_ACCOUNT; |
| if (buf[0] == '1') |
| s->flags |= SLAB_RECLAIM_ACCOUNT; |
| return length; |
| } |
| SLAB_ATTR(reclaim_account); |
| |
| static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & |
| (SLAB_HWCACHE_ALIGN|SLAB_MUST_HWCACHE_ALIGN))); |
| } |
| SLAB_ATTR_RO(hwcache_align); |
| |
| #ifdef CONFIG_ZONE_DMA |
| static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); |
| } |
| SLAB_ATTR_RO(cache_dma); |
| #endif |
| |
| static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU)); |
| } |
| SLAB_ATTR_RO(destroy_by_rcu); |
| |
| static ssize_t red_zone_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); |
| } |
| |
| static ssize_t red_zone_store(struct kmem_cache *s, |
| const char *buf, size_t length) |
| { |
| if (any_slab_objects(s)) |
| return -EBUSY; |
| |
| s->flags &= ~SLAB_RED_ZONE; |
| if (buf[0] == '1') |
| s->flags |= SLAB_RED_ZONE; |
| calculate_sizes(s); |
| return length; |
| } |
| SLAB_ATTR(red_zone); |
| |
| static ssize_t poison_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON)); |
| } |
| |
| static ssize_t poison_store(struct kmem_cache *s, |
| const char *buf, size_t length) |
| { |
| if (any_slab_objects(s)) |
| return -EBUSY; |
| |
| s->flags &= ~SLAB_POISON; |
| if (buf[0] == '1') |
| s->flags |= SLAB_POISON; |
| calculate_sizes(s); |
| return length; |
| } |
| SLAB_ATTR(poison); |
| |
| static ssize_t store_user_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); |
| } |
| |
| static ssize_t store_user_store(struct kmem_cache *s, |
| const char *buf, size_t length) |
| { |
| if (any_slab_objects(s)) |
| return -EBUSY; |
| |
| s->flags &= ~SLAB_STORE_USER; |
| if (buf[0] == '1') |
| s->flags |= SLAB_STORE_USER; |
| calculate_sizes(s); |
| return length; |
| } |
| SLAB_ATTR(store_user); |
| |
| #ifdef CONFIG_NUMA |
| static ssize_t defrag_ratio_show(struct kmem_cache *s, char *buf) |
| { |
| return sprintf(buf, "%d\n", s->defrag_ratio / 10); |
| } |
| |
| static ssize_t defrag_ratio_store(struct kmem_cache *s, |
| const char *buf, size_t length) |
| { |
| int n = simple_strtoul(buf, NULL, 10); |
| |
| if (n < 100) |
| s->defrag_ratio = n * 10; |
| return length; |
| } |
| SLAB_ATTR(defrag_ratio); |
| #endif |
| |
| static struct attribute * slab_attrs[] = { |
| &slab_size_attr.attr, |
| &object_size_attr.attr, |
| &objs_per_slab_attr.attr, |
| &order_attr.attr, |
| &objects_attr.attr, |
| &slabs_attr.attr, |
| &partial_attr.attr, |
| &cpu_slabs_attr.attr, |
| &ctor_attr.attr, |
| &dtor_attr.attr, |
| &aliases_attr.attr, |
| &align_attr.attr, |
| &sanity_checks_attr.attr, |
| &trace_attr.attr, |
| &hwcache_align_attr.attr, |
| &reclaim_account_attr.attr, |
| &destroy_by_rcu_attr.attr, |
| &red_zone_attr.attr, |
| &poison_attr.attr, |
| &store_user_attr.attr, |
| #ifdef CONFIG_ZONE_DMA |
| &cache_dma_attr.attr, |
| #endif |
| #ifdef CONFIG_NUMA |
| &defrag_ratio_attr.attr, |
| #endif |
| NULL |
| }; |
| |
| static struct attribute_group slab_attr_group = { |
| .attrs = slab_attrs, |
| }; |
| |
| static ssize_t slab_attr_show(struct kobject *kobj, |
| struct attribute *attr, |
| char *buf) |
| { |
| struct slab_attribute *attribute; |
| struct kmem_cache *s; |
| int err; |
| |
| attribute = to_slab_attr(attr); |
| s = to_slab(kobj); |
| |
| if (!attribute->show) |
| return -EIO; |
| |
| err = attribute->show(s, buf); |
| |
| return err; |
| } |
| |
| static ssize_t slab_attr_store(struct kobject *kobj, |
| struct attribute *attr, |
| const char *buf, size_t len) |
| { |
| struct slab_attribute *attribute; |
| struct kmem_cache *s; |
| int err; |
| |
| attribute = to_slab_attr(attr); |
| s = to_slab(kobj); |
| |
| if (!attribute->store) |
| return -EIO; |
| |
| err = attribute->store(s, buf, len); |
| |
| return err; |
| } |
| |
| static struct sysfs_ops slab_sysfs_ops = { |
| .show = slab_attr_show, |
| .store = slab_attr_store, |
| }; |
| |
| static struct kobj_type slab_ktype = { |
| .sysfs_ops = &slab_sysfs_ops, |
| }; |
| |
| static int uevent_filter(struct kset *kset, struct kobject *kobj) |
| { |
| struct kobj_type *ktype = get_ktype(kobj); |
| |
| if (ktype == &slab_ktype) |
| return 1; |
| return 0; |
| } |
| |
| static struct kset_uevent_ops slab_uevent_ops = { |
| .filter = uevent_filter, |
| }; |
| |
| decl_subsys(slab, &slab_ktype, &slab_uevent_ops); |
| |
| #define ID_STR_LENGTH 64 |
| |
| /* Create a unique string id for a slab cache: |
| * format |
| * :[flags-]size:[memory address of kmemcache] |
| */ |
| static char *create_unique_id(struct kmem_cache *s) |
| { |
| char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); |
| char *p = name; |
| |
| BUG_ON(!name); |
| |
| *p++ = ':'; |
| /* |
| * First flags affecting slabcache operations. We will only |
| * get here for aliasable slabs so we do not need to support |
| * too many flags. The flags here must cover all flags that |
| * are matched during merging to guarantee that the id is |
| * unique. |
| */ |
| if (s->flags & SLAB_CACHE_DMA) |
| *p++ = 'd'; |
| if (s->flags & SLAB_RECLAIM_ACCOUNT) |
| *p++ = 'a'; |
| if (s->flags & SLAB_DEBUG_FREE) |
| *p++ = 'F'; |
| if (p != name + 1) |
| *p++ = '-'; |
| p += sprintf(p, "%07d", s->size); |
| BUG_ON(p > name + ID_STR_LENGTH - 1); |
| return name; |
| } |
| |
| static int sysfs_slab_add(struct kmem_cache *s) |
| { |
| int err; |
| const char *name; |
| int unmergeable; |
| |
| if (slab_state < SYSFS) |
| /* Defer until later */ |
| return 0; |
| |
| unmergeable = slab_unmergeable(s); |
| if (unmergeable) { |
| /* |
| * Slabcache can never be merged so we can use the name proper. |
| * This is typically the case for debug situations. In that |
| * case we can catch duplicate names easily. |
| */ |
| sysfs_remove_link(&slab_subsys.kset.kobj, s->name); |
| name = s->name; |
| } else { |
| /* |
| * Create a unique name for the slab as a target |
| * for the symlinks. |
| */ |
| name = create_unique_id(s); |
| } |
| |
| kobj_set_kset_s(s, slab_subsys); |
| kobject_set_name(&s->kobj, name); |
| kobject_init(&s->kobj); |
| err = kobject_add(&s->kobj); |
| if (err) |
| return err; |
| |
| err = sysfs_create_group(&s->kobj, &slab_attr_group); |
| if (err) |
| return err; |
| kobject_uevent(&s->kobj, KOBJ_ADD); |
| if (!unmergeable) { |
| /* Setup first alias */ |
| sysfs_slab_alias(s, s->name); |
| kfree(name); |
| } |
| return 0; |
| } |
| |
| static void sysfs_slab_remove(struct kmem_cache *s) |
| { |
| kobject_uevent(&s->kobj, KOBJ_REMOVE); |
| kobject_del(&s->kobj); |
| } |
| |
| /* |
| * Need to buffer aliases during bootup until sysfs becomes |
| * available lest we loose that information. |
| */ |
| struct saved_alias { |
| struct kmem_cache *s; |
| const char *name; |
| struct saved_alias *next; |
| }; |
| |
| struct saved_alias *alias_list; |
| |
| static int sysfs_slab_alias(struct kmem_cache *s, const char *name) |
| { |
| struct saved_alias *al; |
| |
| if (slab_state == SYSFS) { |
| /* |
| * If we have a leftover link then remove it. |
| */ |
| sysfs_remove_link(&slab_subsys.kset.kobj, name); |
| return sysfs_create_link(&slab_subsys.kset.kobj, |
| &s->kobj, name); |
| } |
| |
| al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); |
| if (!al) |
| return -ENOMEM; |
| |
| al->s = s; |
| al->name = name; |
| al->next = alias_list; |
| alias_list = al; |
| return 0; |
| } |
| |
| static int __init slab_sysfs_init(void) |
| { |
| int err; |
| |
| err = subsystem_register(&slab_subsys); |
| if (err) { |
| printk(KERN_ERR "Cannot register slab subsystem.\n"); |
| return -ENOSYS; |
| } |
| |
| finish_bootstrap(); |
| |
| while (alias_list) { |
| struct saved_alias *al = alias_list; |
| |
| alias_list = alias_list->next; |
| err = sysfs_slab_alias(al->s, al->name); |
| BUG_ON(err); |
| kfree(al); |
| } |
| |
| resiliency_test(); |
| return 0; |
| } |
| |
| __initcall(slab_sysfs_init); |
| #else |
| __initcall(finish_bootstrap); |
| #endif |