Commit | Line | Data |
---|---|---|
81819f0f CL |
1 | /* |
2 | * SLUB: A slab allocator that limits cache line use instead of queuing | |
3 | * objects in per cpu and per node lists. | |
4 | * | |
881db7fb CL |
5 | * The allocator synchronizes using per slab locks or atomic operatios |
6 | * and only uses a centralized lock to manage a pool of partial slabs. | |
81819f0f | 7 | * |
cde53535 | 8 | * (C) 2007 SGI, Christoph Lameter |
881db7fb | 9 | * (C) 2011 Linux Foundation, Christoph Lameter |
81819f0f CL |
10 | */ |
11 | ||
12 | #include <linux/mm.h> | |
1eb5ac64 | 13 | #include <linux/swap.h> /* struct reclaim_state */ |
81819f0f CL |
14 | #include <linux/module.h> |
15 | #include <linux/bit_spinlock.h> | |
16 | #include <linux/interrupt.h> | |
17 | #include <linux/bitops.h> | |
18 | #include <linux/slab.h> | |
97d06609 | 19 | #include "slab.h" |
7b3c3a50 | 20 | #include <linux/proc_fs.h> |
3ac38faa | 21 | #include <linux/notifier.h> |
81819f0f | 22 | #include <linux/seq_file.h> |
a79316c6 | 23 | #include <linux/kasan.h> |
5a896d9e | 24 | #include <linux/kmemcheck.h> |
81819f0f CL |
25 | #include <linux/cpu.h> |
26 | #include <linux/cpuset.h> | |
27 | #include <linux/mempolicy.h> | |
28 | #include <linux/ctype.h> | |
3ac7fe5a | 29 | #include <linux/debugobjects.h> |
81819f0f | 30 | #include <linux/kallsyms.h> |
b9049e23 | 31 | #include <linux/memory.h> |
f8bd2258 | 32 | #include <linux/math64.h> |
773ff60e | 33 | #include <linux/fault-inject.h> |
bfa71457 | 34 | #include <linux/stacktrace.h> |
4de900b4 | 35 | #include <linux/prefetch.h> |
2633d7a0 | 36 | #include <linux/memcontrol.h> |
81819f0f | 37 | |
4a92379b RK |
38 | #include <trace/events/kmem.h> |
39 | ||
072bb0aa MG |
40 | #include "internal.h" |
41 | ||
81819f0f CL |
42 | /* |
43 | * Lock order: | |
18004c5d | 44 | * 1. slab_mutex (Global Mutex) |
881db7fb CL |
45 | * 2. node->list_lock |
46 | * 3. slab_lock(page) (Only on some arches and for debugging) | |
81819f0f | 47 | * |
18004c5d | 48 | * slab_mutex |
881db7fb | 49 | * |
18004c5d | 50 | * The role of the slab_mutex is to protect the list of all the slabs |
881db7fb CL |
51 | * and to synchronize major metadata changes to slab cache structures. |
52 | * | |
53 | * The slab_lock is only used for debugging and on arches that do not | |
54 | * have the ability to do a cmpxchg_double. It only protects the second | |
55 | * double word in the page struct. Meaning | |
56 | * A. page->freelist -> List of object free in a page | |
57 | * B. page->counters -> Counters of objects | |
58 | * C. page->frozen -> frozen state | |
59 | * | |
60 | * If a slab is frozen then it is exempt from list management. It is not | |
61 | * on any list. The processor that froze the slab is the one who can | |
62 | * perform list operations on the page. Other processors may put objects | |
63 | * onto the freelist but the processor that froze the slab is the only | |
64 | * one that can retrieve the objects from the page's freelist. | |
81819f0f CL |
65 | * |
66 | * The list_lock protects the partial and full list on each node and | |
67 | * the partial slab counter. If taken then no new slabs may be added or | |
68 | * removed from the lists nor make the number of partial slabs be modified. | |
69 | * (Note that the total number of slabs is an atomic value that may be | |
70 | * modified without taking the list lock). | |
71 | * | |
72 | * The list_lock is a centralized lock and thus we avoid taking it as | |
73 | * much as possible. As long as SLUB does not have to handle partial | |
74 | * slabs, operations can continue without any centralized lock. F.e. | |
75 | * allocating a long series of objects that fill up slabs does not require | |
76 | * the list lock. | |
81819f0f CL |
77 | * Interrupts are disabled during allocation and deallocation in order to |
78 | * make the slab allocator safe to use in the context of an irq. In addition | |
79 | * interrupts are disabled to ensure that the processor does not change | |
80 | * while handling per_cpu slabs, due to kernel preemption. | |
81 | * | |
82 | * SLUB assigns one slab for allocation to each processor. | |
83 | * Allocations only occur from these slabs called cpu slabs. | |
84 | * | |
672bba3a CL |
85 | * Slabs with free elements are kept on a partial list and during regular |
86 | * operations no list for full slabs is used. If an object in a full slab is | |
81819f0f | 87 | * freed then the slab will show up again on the partial lists. |
672bba3a CL |
88 | * We track full slabs for debugging purposes though because otherwise we |
89 | * cannot scan all objects. | |
81819f0f CL |
90 | * |
91 | * Slabs are freed when they become empty. Teardown and setup is | |
92 | * minimal so we rely on the page allocators per cpu caches for | |
93 | * fast frees and allocs. | |
94 | * | |
95 | * Overloading of page flags that are otherwise used for LRU management. | |
96 | * | |
4b6f0750 CL |
97 | * PageActive The slab is frozen and exempt from list processing. |
98 | * This means that the slab is dedicated to a purpose | |
99 | * such as satisfying allocations for a specific | |
100 | * processor. Objects may be freed in the slab while | |
101 | * it is frozen but slab_free will then skip the usual | |
102 | * list operations. It is up to the processor holding | |
103 | * the slab to integrate the slab into the slab lists | |
104 | * when the slab is no longer needed. | |
105 | * | |
106 | * One use of this flag is to mark slabs that are | |
107 | * used for allocations. Then such a slab becomes a cpu | |
108 | * slab. The cpu slab may be equipped with an additional | |
dfb4f096 | 109 | * freelist that allows lockless access to |
894b8788 CL |
110 | * free objects in addition to the regular freelist |
111 | * that requires the slab lock. | |
81819f0f CL |
112 | * |
113 | * PageError Slab requires special handling due to debug | |
114 | * options set. This moves slab handling out of | |
894b8788 | 115 | * the fast path and disables lockless freelists. |
81819f0f CL |
116 | */ |
117 | ||
af537b0a CL |
118 | static inline int kmem_cache_debug(struct kmem_cache *s) |
119 | { | |
5577bd8a | 120 | #ifdef CONFIG_SLUB_DEBUG |
af537b0a | 121 | return unlikely(s->flags & SLAB_DEBUG_FLAGS); |
5577bd8a | 122 | #else |
af537b0a | 123 | return 0; |
5577bd8a | 124 | #endif |
af537b0a | 125 | } |
5577bd8a | 126 | |
d86bd1be JK |
127 | static inline void *fixup_red_left(struct kmem_cache *s, void *p) |
128 | { | |
129 | if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) | |
130 | p += s->red_left_pad; | |
131 | ||
132 | return p; | |
133 | } | |
134 | ||
345c905d JK |
135 | static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) |
136 | { | |
137 | #ifdef CONFIG_SLUB_CPU_PARTIAL | |
138 | return !kmem_cache_debug(s); | |
139 | #else | |
140 | return false; | |
141 | #endif | |
142 | } | |
143 | ||
81819f0f CL |
144 | /* |
145 | * Issues still to be resolved: | |
146 | * | |
81819f0f CL |
147 | * - Support PAGE_ALLOC_DEBUG. Should be easy to do. |
148 | * | |
81819f0f CL |
149 | * - Variable sizing of the per node arrays |
150 | */ | |
151 | ||
152 | /* Enable to test recovery from slab corruption on boot */ | |
153 | #undef SLUB_RESILIENCY_TEST | |
154 | ||
b789ef51 CL |
155 | /* Enable to log cmpxchg failures */ |
156 | #undef SLUB_DEBUG_CMPXCHG | |
157 | ||
2086d26a CL |
158 | /* |
159 | * Mininum number of partial slabs. These will be left on the partial | |
160 | * lists even if they are empty. kmem_cache_shrink may reclaim them. | |
161 | */ | |
76be8950 | 162 | #define MIN_PARTIAL 5 |
e95eed57 | 163 | |
2086d26a CL |
164 | /* |
165 | * Maximum number of desirable partial slabs. | |
166 | * The existence of more partial slabs makes kmem_cache_shrink | |
721ae22a | 167 | * sort the partial list by the number of objects in use. |
2086d26a CL |
168 | */ |
169 | #define MAX_PARTIAL 10 | |
170 | ||
becfda68 | 171 | #define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ |
81819f0f | 172 | SLAB_POISON | SLAB_STORE_USER) |
672bba3a | 173 | |
149daaf3 LA |
174 | /* |
175 | * These debug flags cannot use CMPXCHG because there might be consistency | |
176 | * issues when checking or reading debug information | |
177 | */ | |
178 | #define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ | |
179 | SLAB_TRACE) | |
180 | ||
181 | ||
fa5ec8a1 | 182 | /* |
3de47213 DR |
183 | * Debugging flags that require metadata to be stored in the slab. These get |
184 | * disabled when slub_debug=O is used and a cache's min order increases with | |
185 | * metadata. | |
fa5ec8a1 | 186 | */ |
3de47213 | 187 | #define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) |
fa5ec8a1 | 188 | |
210b5c06 CG |
189 | #define OO_SHIFT 16 |
190 | #define OO_MASK ((1 << OO_SHIFT) - 1) | |
50d5c41c | 191 | #define MAX_OBJS_PER_PAGE 32767 /* since page.objects is u15 */ |
210b5c06 | 192 | |
81819f0f | 193 | /* Internal SLUB flags */ |
f90ec390 | 194 | #define __OBJECT_POISON 0x80000000UL /* Poison object */ |
b789ef51 | 195 | #define __CMPXCHG_DOUBLE 0x40000000UL /* Use cmpxchg_double */ |
81819f0f | 196 | |
81819f0f CL |
197 | #ifdef CONFIG_SMP |
198 | static struct notifier_block slab_notifier; | |
199 | #endif | |
200 | ||
02cbc874 CL |
201 | /* |
202 | * Tracking user of a slab. | |
203 | */ | |
d6543e39 | 204 | #define TRACK_ADDRS_COUNT 16 |
02cbc874 | 205 | struct track { |
ce71e27c | 206 | unsigned long addr; /* Called from address */ |
d6543e39 BG |
207 | #ifdef CONFIG_STACKTRACE |
208 | unsigned long addrs[TRACK_ADDRS_COUNT]; /* Called from address */ | |
209 | #endif | |
02cbc874 CL |
210 | int cpu; /* Was running on cpu */ |
211 | int pid; /* Pid context */ | |
212 | unsigned long when; /* When did the operation occur */ | |
213 | }; | |
214 | ||
215 | enum track_item { TRACK_ALLOC, TRACK_FREE }; | |
216 | ||
ab4d5ed5 | 217 | #ifdef CONFIG_SYSFS |
81819f0f CL |
218 | static int sysfs_slab_add(struct kmem_cache *); |
219 | static int sysfs_slab_alias(struct kmem_cache *, const char *); | |
107dab5c | 220 | static void memcg_propagate_slab_attrs(struct kmem_cache *s); |
81819f0f | 221 | #else |
0c710013 CL |
222 | static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } |
223 | static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) | |
224 | { return 0; } | |
107dab5c | 225 | static inline void memcg_propagate_slab_attrs(struct kmem_cache *s) { } |
81819f0f CL |
226 | #endif |
227 | ||
4fdccdfb | 228 | static inline void stat(const struct kmem_cache *s, enum stat_item si) |
8ff12cfc CL |
229 | { |
230 | #ifdef CONFIG_SLUB_STATS | |
88da03a6 CL |
231 | /* |
232 | * The rmw is racy on a preemptible kernel but this is acceptable, so | |
233 | * avoid this_cpu_add()'s irq-disable overhead. | |
234 | */ | |
235 | raw_cpu_inc(s->cpu_slab->stat[si]); | |
8ff12cfc CL |
236 | #endif |
237 | } | |
238 | ||
81819f0f CL |
239 | /******************************************************************** |
240 | * Core slab cache functions | |
241 | *******************************************************************/ | |
242 | ||
7656c72b CL |
243 | static inline void *get_freepointer(struct kmem_cache *s, void *object) |
244 | { | |
245 | return *(void **)(object + s->offset); | |
246 | } | |
247 | ||
0ad9500e ED |
248 | static void prefetch_freepointer(const struct kmem_cache *s, void *object) |
249 | { | |
250 | prefetch(object + s->offset); | |
251 | } | |
252 | ||
1393d9a1 CL |
253 | static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) |
254 | { | |
255 | void *p; | |
256 | ||
257 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
258 | probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p)); | |
259 | #else | |
260 | p = get_freepointer(s, object); | |
261 | #endif | |
262 | return p; | |
263 | } | |
264 | ||
7656c72b CL |
265 | static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) |
266 | { | |
267 | *(void **)(object + s->offset) = fp; | |
268 | } | |
269 | ||
270 | /* Loop over all objects in a slab */ | |
224a88be | 271 | #define for_each_object(__p, __s, __addr, __objects) \ |
d86bd1be JK |
272 | for (__p = fixup_red_left(__s, __addr); \ |
273 | __p < (__addr) + (__objects) * (__s)->size; \ | |
274 | __p += (__s)->size) | |
7656c72b | 275 | |
54266640 | 276 | #define for_each_object_idx(__p, __idx, __s, __addr, __objects) \ |
d86bd1be JK |
277 | for (__p = fixup_red_left(__s, __addr), __idx = 1; \ |
278 | __idx <= __objects; \ | |
279 | __p += (__s)->size, __idx++) | |
54266640 | 280 | |
7656c72b CL |
281 | /* Determine object index from a given position */ |
282 | static inline int slab_index(void *p, struct kmem_cache *s, void *addr) | |
283 | { | |
284 | return (p - addr) / s->size; | |
285 | } | |
286 | ||
ab9a0f19 LJ |
287 | static inline int order_objects(int order, unsigned long size, int reserved) |
288 | { | |
289 | return ((PAGE_SIZE << order) - reserved) / size; | |
290 | } | |
291 | ||
834f3d11 | 292 | static inline struct kmem_cache_order_objects oo_make(int order, |
ab9a0f19 | 293 | unsigned long size, int reserved) |
834f3d11 CL |
294 | { |
295 | struct kmem_cache_order_objects x = { | |
ab9a0f19 | 296 | (order << OO_SHIFT) + order_objects(order, size, reserved) |
834f3d11 CL |
297 | }; |
298 | ||
299 | return x; | |
300 | } | |
301 | ||
302 | static inline int oo_order(struct kmem_cache_order_objects x) | |
303 | { | |
210b5c06 | 304 | return x.x >> OO_SHIFT; |
834f3d11 CL |
305 | } |
306 | ||
307 | static inline int oo_objects(struct kmem_cache_order_objects x) | |
308 | { | |
210b5c06 | 309 | return x.x & OO_MASK; |
834f3d11 CL |
310 | } |
311 | ||
881db7fb CL |
312 | /* |
313 | * Per slab locking using the pagelock | |
314 | */ | |
315 | static __always_inline void slab_lock(struct page *page) | |
316 | { | |
48c935ad | 317 | VM_BUG_ON_PAGE(PageTail(page), page); |
881db7fb CL |
318 | bit_spin_lock(PG_locked, &page->flags); |
319 | } | |
320 | ||
321 | static __always_inline void slab_unlock(struct page *page) | |
322 | { | |
48c935ad | 323 | VM_BUG_ON_PAGE(PageTail(page), page); |
881db7fb CL |
324 | __bit_spin_unlock(PG_locked, &page->flags); |
325 | } | |
326 | ||
a0320865 DH |
327 | static inline void set_page_slub_counters(struct page *page, unsigned long counters_new) |
328 | { | |
329 | struct page tmp; | |
330 | tmp.counters = counters_new; | |
331 | /* | |
332 | * page->counters can cover frozen/inuse/objects as well | |
333 | * as page->_count. If we assign to ->counters directly | |
334 | * we run the risk of losing updates to page->_count, so | |
335 | * be careful and only assign to the fields we need. | |
336 | */ | |
337 | page->frozen = tmp.frozen; | |
338 | page->inuse = tmp.inuse; | |
339 | page->objects = tmp.objects; | |
340 | } | |
341 | ||
1d07171c CL |
342 | /* Interrupts must be disabled (for the fallback code to work right) */ |
343 | static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page, | |
344 | void *freelist_old, unsigned long counters_old, | |
345 | void *freelist_new, unsigned long counters_new, | |
346 | const char *n) | |
347 | { | |
348 | VM_BUG_ON(!irqs_disabled()); | |
2565409f HC |
349 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
350 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
1d07171c | 351 | if (s->flags & __CMPXCHG_DOUBLE) { |
cdcd6298 | 352 | if (cmpxchg_double(&page->freelist, &page->counters, |
0aa9a13d DC |
353 | freelist_old, counters_old, |
354 | freelist_new, counters_new)) | |
6f6528a1 | 355 | return true; |
1d07171c CL |
356 | } else |
357 | #endif | |
358 | { | |
359 | slab_lock(page); | |
d0e0ac97 CG |
360 | if (page->freelist == freelist_old && |
361 | page->counters == counters_old) { | |
1d07171c | 362 | page->freelist = freelist_new; |
a0320865 | 363 | set_page_slub_counters(page, counters_new); |
1d07171c | 364 | slab_unlock(page); |
6f6528a1 | 365 | return true; |
1d07171c CL |
366 | } |
367 | slab_unlock(page); | |
368 | } | |
369 | ||
370 | cpu_relax(); | |
371 | stat(s, CMPXCHG_DOUBLE_FAIL); | |
372 | ||
373 | #ifdef SLUB_DEBUG_CMPXCHG | |
f9f58285 | 374 | pr_info("%s %s: cmpxchg double redo ", n, s->name); |
1d07171c CL |
375 | #endif |
376 | ||
6f6528a1 | 377 | return false; |
1d07171c CL |
378 | } |
379 | ||
b789ef51 CL |
380 | static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page, |
381 | void *freelist_old, unsigned long counters_old, | |
382 | void *freelist_new, unsigned long counters_new, | |
383 | const char *n) | |
384 | { | |
2565409f HC |
385 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
386 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
b789ef51 | 387 | if (s->flags & __CMPXCHG_DOUBLE) { |
cdcd6298 | 388 | if (cmpxchg_double(&page->freelist, &page->counters, |
0aa9a13d DC |
389 | freelist_old, counters_old, |
390 | freelist_new, counters_new)) | |
6f6528a1 | 391 | return true; |
b789ef51 CL |
392 | } else |
393 | #endif | |
394 | { | |
1d07171c CL |
395 | unsigned long flags; |
396 | ||
397 | local_irq_save(flags); | |
881db7fb | 398 | slab_lock(page); |
d0e0ac97 CG |
399 | if (page->freelist == freelist_old && |
400 | page->counters == counters_old) { | |
b789ef51 | 401 | page->freelist = freelist_new; |
a0320865 | 402 | set_page_slub_counters(page, counters_new); |
881db7fb | 403 | slab_unlock(page); |
1d07171c | 404 | local_irq_restore(flags); |
6f6528a1 | 405 | return true; |
b789ef51 | 406 | } |
881db7fb | 407 | slab_unlock(page); |
1d07171c | 408 | local_irq_restore(flags); |
b789ef51 CL |
409 | } |
410 | ||
411 | cpu_relax(); | |
412 | stat(s, CMPXCHG_DOUBLE_FAIL); | |
413 | ||
414 | #ifdef SLUB_DEBUG_CMPXCHG | |
f9f58285 | 415 | pr_info("%s %s: cmpxchg double redo ", n, s->name); |
b789ef51 CL |
416 | #endif |
417 | ||
6f6528a1 | 418 | return false; |
b789ef51 CL |
419 | } |
420 | ||
41ecc55b | 421 | #ifdef CONFIG_SLUB_DEBUG |
5f80b13a CL |
422 | /* |
423 | * Determine a map of object in use on a page. | |
424 | * | |
881db7fb | 425 | * Node listlock must be held to guarantee that the page does |
5f80b13a CL |
426 | * not vanish from under us. |
427 | */ | |
428 | static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map) | |
429 | { | |
430 | void *p; | |
431 | void *addr = page_address(page); | |
432 | ||
433 | for (p = page->freelist; p; p = get_freepointer(s, p)) | |
434 | set_bit(slab_index(p, s, addr), map); | |
435 | } | |
436 | ||
d86bd1be JK |
437 | static inline int size_from_object(struct kmem_cache *s) |
438 | { | |
439 | if (s->flags & SLAB_RED_ZONE) | |
440 | return s->size - s->red_left_pad; | |
441 | ||
442 | return s->size; | |
443 | } | |
444 | ||
445 | static inline void *restore_red_left(struct kmem_cache *s, void *p) | |
446 | { | |
447 | if (s->flags & SLAB_RED_ZONE) | |
448 | p -= s->red_left_pad; | |
449 | ||
450 | return p; | |
451 | } | |
452 | ||
41ecc55b CL |
453 | /* |
454 | * Debug settings: | |
455 | */ | |
89d3c87e | 456 | #if defined(CONFIG_SLUB_DEBUG_ON) |
f0630fff | 457 | static int slub_debug = DEBUG_DEFAULT_FLAGS; |
89d3c87e AR |
458 | #elif defined(CONFIG_KASAN) |
459 | static int slub_debug = SLAB_STORE_USER; | |
f0630fff | 460 | #else |
41ecc55b | 461 | static int slub_debug; |
f0630fff | 462 | #endif |
41ecc55b CL |
463 | |
464 | static char *slub_debug_slabs; | |
fa5ec8a1 | 465 | static int disable_higher_order_debug; |
41ecc55b | 466 | |
a79316c6 AR |
467 | /* |
468 | * slub is about to manipulate internal object metadata. This memory lies | |
469 | * outside the range of the allocated object, so accessing it would normally | |
470 | * be reported by kasan as a bounds error. metadata_access_enable() is used | |
471 | * to tell kasan that these accesses are OK. | |
472 | */ | |
473 | static inline void metadata_access_enable(void) | |
474 | { | |
475 | kasan_disable_current(); | |
476 | } | |
477 | ||
478 | static inline void metadata_access_disable(void) | |
479 | { | |
480 | kasan_enable_current(); | |
481 | } | |
482 | ||
81819f0f CL |
483 | /* |
484 | * Object debugging | |
485 | */ | |
d86bd1be JK |
486 | |
487 | /* Verify that a pointer has an address that is valid within a slab page */ | |
488 | static inline int check_valid_pointer(struct kmem_cache *s, | |
489 | struct page *page, void *object) | |
490 | { | |
491 | void *base; | |
492 | ||
493 | if (!object) | |
494 | return 1; | |
495 | ||
496 | base = page_address(page); | |
497 | object = restore_red_left(s, object); | |
498 | if (object < base || object >= base + page->objects * s->size || | |
499 | (object - base) % s->size) { | |
500 | return 0; | |
501 | } | |
502 | ||
503 | return 1; | |
504 | } | |
505 | ||
81819f0f CL |
506 | static void print_section(char *text, u8 *addr, unsigned int length) |
507 | { | |
a79316c6 | 508 | metadata_access_enable(); |
ffc79d28 SAS |
509 | print_hex_dump(KERN_ERR, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, |
510 | length, 1); | |
a79316c6 | 511 | metadata_access_disable(); |
81819f0f CL |
512 | } |
513 | ||
81819f0f CL |
514 | static struct track *get_track(struct kmem_cache *s, void *object, |
515 | enum track_item alloc) | |
516 | { | |
517 | struct track *p; | |
518 | ||
519 | if (s->offset) | |
520 | p = object + s->offset + sizeof(void *); | |
521 | else | |
522 | p = object + s->inuse; | |
523 | ||
524 | return p + alloc; | |
525 | } | |
526 | ||
527 | static void set_track(struct kmem_cache *s, void *object, | |
ce71e27c | 528 | enum track_item alloc, unsigned long addr) |
81819f0f | 529 | { |
1a00df4a | 530 | struct track *p = get_track(s, object, alloc); |
81819f0f | 531 | |
81819f0f | 532 | if (addr) { |
d6543e39 BG |
533 | #ifdef CONFIG_STACKTRACE |
534 | struct stack_trace trace; | |
535 | int i; | |
536 | ||
537 | trace.nr_entries = 0; | |
538 | trace.max_entries = TRACK_ADDRS_COUNT; | |
539 | trace.entries = p->addrs; | |
540 | trace.skip = 3; | |
a79316c6 | 541 | metadata_access_enable(); |
d6543e39 | 542 | save_stack_trace(&trace); |
a79316c6 | 543 | metadata_access_disable(); |
d6543e39 BG |
544 | |
545 | /* See rant in lockdep.c */ | |
546 | if (trace.nr_entries != 0 && | |
547 | trace.entries[trace.nr_entries - 1] == ULONG_MAX) | |
548 | trace.nr_entries--; | |
549 | ||
550 | for (i = trace.nr_entries; i < TRACK_ADDRS_COUNT; i++) | |
551 | p->addrs[i] = 0; | |
552 | #endif | |
81819f0f CL |
553 | p->addr = addr; |
554 | p->cpu = smp_processor_id(); | |
88e4ccf2 | 555 | p->pid = current->pid; |
81819f0f CL |
556 | p->when = jiffies; |
557 | } else | |
558 | memset(p, 0, sizeof(struct track)); | |
559 | } | |
560 | ||
81819f0f CL |
561 | static void init_tracking(struct kmem_cache *s, void *object) |
562 | { | |
24922684 CL |
563 | if (!(s->flags & SLAB_STORE_USER)) |
564 | return; | |
565 | ||
ce71e27c EGM |
566 | set_track(s, object, TRACK_FREE, 0UL); |
567 | set_track(s, object, TRACK_ALLOC, 0UL); | |
81819f0f CL |
568 | } |
569 | ||
570 | static void print_track(const char *s, struct track *t) | |
571 | { | |
572 | if (!t->addr) | |
573 | return; | |
574 | ||
f9f58285 FF |
575 | pr_err("INFO: %s in %pS age=%lu cpu=%u pid=%d\n", |
576 | s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid); | |
d6543e39 BG |
577 | #ifdef CONFIG_STACKTRACE |
578 | { | |
579 | int i; | |
580 | for (i = 0; i < TRACK_ADDRS_COUNT; i++) | |
581 | if (t->addrs[i]) | |
f9f58285 | 582 | pr_err("\t%pS\n", (void *)t->addrs[i]); |
d6543e39 BG |
583 | else |
584 | break; | |
585 | } | |
586 | #endif | |
24922684 CL |
587 | } |
588 | ||
589 | static void print_tracking(struct kmem_cache *s, void *object) | |
590 | { | |
591 | if (!(s->flags & SLAB_STORE_USER)) | |
592 | return; | |
593 | ||
594 | print_track("Allocated", get_track(s, object, TRACK_ALLOC)); | |
595 | print_track("Freed", get_track(s, object, TRACK_FREE)); | |
596 | } | |
597 | ||
598 | static void print_page_info(struct page *page) | |
599 | { | |
f9f58285 | 600 | pr_err("INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n", |
d0e0ac97 | 601 | page, page->objects, page->inuse, page->freelist, page->flags); |
24922684 CL |
602 | |
603 | } | |
604 | ||
605 | static void slab_bug(struct kmem_cache *s, char *fmt, ...) | |
606 | { | |
ecc42fbe | 607 | struct va_format vaf; |
24922684 | 608 | va_list args; |
24922684 CL |
609 | |
610 | va_start(args, fmt); | |
ecc42fbe FF |
611 | vaf.fmt = fmt; |
612 | vaf.va = &args; | |
f9f58285 | 613 | pr_err("=============================================================================\n"); |
ecc42fbe | 614 | pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); |
f9f58285 | 615 | pr_err("-----------------------------------------------------------------------------\n\n"); |
645df230 | 616 | |
373d4d09 | 617 | add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); |
ecc42fbe | 618 | va_end(args); |
81819f0f CL |
619 | } |
620 | ||
24922684 CL |
621 | static void slab_fix(struct kmem_cache *s, char *fmt, ...) |
622 | { | |
ecc42fbe | 623 | struct va_format vaf; |
24922684 | 624 | va_list args; |
24922684 CL |
625 | |
626 | va_start(args, fmt); | |
ecc42fbe FF |
627 | vaf.fmt = fmt; |
628 | vaf.va = &args; | |
629 | pr_err("FIX %s: %pV\n", s->name, &vaf); | |
24922684 | 630 | va_end(args); |
24922684 CL |
631 | } |
632 | ||
633 | static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) | |
81819f0f CL |
634 | { |
635 | unsigned int off; /* Offset of last byte */ | |
a973e9dd | 636 | u8 *addr = page_address(page); |
24922684 CL |
637 | |
638 | print_tracking(s, p); | |
639 | ||
640 | print_page_info(page); | |
641 | ||
f9f58285 FF |
642 | pr_err("INFO: Object 0x%p @offset=%tu fp=0x%p\n\n", |
643 | p, p - addr, get_freepointer(s, p)); | |
24922684 | 644 | |
d86bd1be JK |
645 | if (s->flags & SLAB_RED_ZONE) |
646 | print_section("Redzone ", p - s->red_left_pad, s->red_left_pad); | |
647 | else if (p > addr + 16) | |
ffc79d28 | 648 | print_section("Bytes b4 ", p - 16, 16); |
81819f0f | 649 | |
3b0efdfa | 650 | print_section("Object ", p, min_t(unsigned long, s->object_size, |
ffc79d28 | 651 | PAGE_SIZE)); |
81819f0f | 652 | if (s->flags & SLAB_RED_ZONE) |
3b0efdfa CL |
653 | print_section("Redzone ", p + s->object_size, |
654 | s->inuse - s->object_size); | |
81819f0f | 655 | |
81819f0f CL |
656 | if (s->offset) |
657 | off = s->offset + sizeof(void *); | |
658 | else | |
659 | off = s->inuse; | |
660 | ||
24922684 | 661 | if (s->flags & SLAB_STORE_USER) |
81819f0f | 662 | off += 2 * sizeof(struct track); |
81819f0f | 663 | |
d86bd1be | 664 | if (off != size_from_object(s)) |
81819f0f | 665 | /* Beginning of the filler is the free pointer */ |
d86bd1be | 666 | print_section("Padding ", p + off, size_from_object(s) - off); |
24922684 CL |
667 | |
668 | dump_stack(); | |
81819f0f CL |
669 | } |
670 | ||
75c66def | 671 | void object_err(struct kmem_cache *s, struct page *page, |
81819f0f CL |
672 | u8 *object, char *reason) |
673 | { | |
3dc50637 | 674 | slab_bug(s, "%s", reason); |
24922684 | 675 | print_trailer(s, page, object); |
81819f0f CL |
676 | } |
677 | ||
d0e0ac97 CG |
678 | static void slab_err(struct kmem_cache *s, struct page *page, |
679 | const char *fmt, ...) | |
81819f0f CL |
680 | { |
681 | va_list args; | |
682 | char buf[100]; | |
683 | ||
24922684 CL |
684 | va_start(args, fmt); |
685 | vsnprintf(buf, sizeof(buf), fmt, args); | |
81819f0f | 686 | va_end(args); |
3dc50637 | 687 | slab_bug(s, "%s", buf); |
24922684 | 688 | print_page_info(page); |
81819f0f CL |
689 | dump_stack(); |
690 | } | |
691 | ||
f7cb1933 | 692 | static void init_object(struct kmem_cache *s, void *object, u8 val) |
81819f0f CL |
693 | { |
694 | u8 *p = object; | |
695 | ||
d86bd1be JK |
696 | if (s->flags & SLAB_RED_ZONE) |
697 | memset(p - s->red_left_pad, val, s->red_left_pad); | |
698 | ||
81819f0f | 699 | if (s->flags & __OBJECT_POISON) { |
3b0efdfa CL |
700 | memset(p, POISON_FREE, s->object_size - 1); |
701 | p[s->object_size - 1] = POISON_END; | |
81819f0f CL |
702 | } |
703 | ||
704 | if (s->flags & SLAB_RED_ZONE) | |
3b0efdfa | 705 | memset(p + s->object_size, val, s->inuse - s->object_size); |
81819f0f CL |
706 | } |
707 | ||
24922684 CL |
708 | static void restore_bytes(struct kmem_cache *s, char *message, u8 data, |
709 | void *from, void *to) | |
710 | { | |
711 | slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data); | |
712 | memset(from, data, to - from); | |
713 | } | |
714 | ||
715 | static int check_bytes_and_report(struct kmem_cache *s, struct page *page, | |
716 | u8 *object, char *what, | |
06428780 | 717 | u8 *start, unsigned int value, unsigned int bytes) |
24922684 CL |
718 | { |
719 | u8 *fault; | |
720 | u8 *end; | |
721 | ||
a79316c6 | 722 | metadata_access_enable(); |
79824820 | 723 | fault = memchr_inv(start, value, bytes); |
a79316c6 | 724 | metadata_access_disable(); |
24922684 CL |
725 | if (!fault) |
726 | return 1; | |
727 | ||
728 | end = start + bytes; | |
729 | while (end > fault && end[-1] == value) | |
730 | end--; | |
731 | ||
732 | slab_bug(s, "%s overwritten", what); | |
f9f58285 | 733 | pr_err("INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n", |
24922684 CL |
734 | fault, end - 1, fault[0], value); |
735 | print_trailer(s, page, object); | |
736 | ||
737 | restore_bytes(s, what, value, fault, end); | |
738 | return 0; | |
81819f0f CL |
739 | } |
740 | ||
81819f0f CL |
741 | /* |
742 | * Object layout: | |
743 | * | |
744 | * object address | |
745 | * Bytes of the object to be managed. | |
746 | * If the freepointer may overlay the object then the free | |
747 | * pointer is the first word of the object. | |
672bba3a | 748 | * |
81819f0f CL |
749 | * Poisoning uses 0x6b (POISON_FREE) and the last byte is |
750 | * 0xa5 (POISON_END) | |
751 | * | |
3b0efdfa | 752 | * object + s->object_size |
81819f0f | 753 | * Padding to reach word boundary. This is also used for Redzoning. |
672bba3a | 754 | * Padding is extended by another word if Redzoning is enabled and |
3b0efdfa | 755 | * object_size == inuse. |
672bba3a | 756 | * |
81819f0f CL |
757 | * We fill with 0xbb (RED_INACTIVE) for inactive objects and with |
758 | * 0xcc (RED_ACTIVE) for objects in use. | |
759 | * | |
760 | * object + s->inuse | |
672bba3a CL |
761 | * Meta data starts here. |
762 | * | |
81819f0f CL |
763 | * A. Free pointer (if we cannot overwrite object on free) |
764 | * B. Tracking data for SLAB_STORE_USER | |
672bba3a | 765 | * C. Padding to reach required alignment boundary or at mininum |
6446faa2 | 766 | * one word if debugging is on to be able to detect writes |
672bba3a CL |
767 | * before the word boundary. |
768 | * | |
769 | * Padding is done using 0x5a (POISON_INUSE) | |
81819f0f CL |
770 | * |
771 | * object + s->size | |
672bba3a | 772 | * Nothing is used beyond s->size. |
81819f0f | 773 | * |
3b0efdfa | 774 | * If slabcaches are merged then the object_size and inuse boundaries are mostly |
672bba3a | 775 | * ignored. And therefore no slab options that rely on these boundaries |
81819f0f CL |
776 | * may be used with merged slabcaches. |
777 | */ | |
778 | ||
81819f0f CL |
779 | static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) |
780 | { | |
781 | unsigned long off = s->inuse; /* The end of info */ | |
782 | ||
783 | if (s->offset) | |
784 | /* Freepointer is placed after the object. */ | |
785 | off += sizeof(void *); | |
786 | ||
787 | if (s->flags & SLAB_STORE_USER) | |
788 | /* We also have user information there */ | |
789 | off += 2 * sizeof(struct track); | |
790 | ||
d86bd1be | 791 | if (size_from_object(s) == off) |
81819f0f CL |
792 | return 1; |
793 | ||
24922684 | 794 | return check_bytes_and_report(s, page, p, "Object padding", |
d86bd1be | 795 | p + off, POISON_INUSE, size_from_object(s) - off); |
81819f0f CL |
796 | } |
797 | ||
39b26464 | 798 | /* Check the pad bytes at the end of a slab page */ |
81819f0f CL |
799 | static int slab_pad_check(struct kmem_cache *s, struct page *page) |
800 | { | |
24922684 CL |
801 | u8 *start; |
802 | u8 *fault; | |
803 | u8 *end; | |
804 | int length; | |
805 | int remainder; | |
81819f0f CL |
806 | |
807 | if (!(s->flags & SLAB_POISON)) | |
808 | return 1; | |
809 | ||
a973e9dd | 810 | start = page_address(page); |
ab9a0f19 | 811 | length = (PAGE_SIZE << compound_order(page)) - s->reserved; |
39b26464 CL |
812 | end = start + length; |
813 | remainder = length % s->size; | |
81819f0f CL |
814 | if (!remainder) |
815 | return 1; | |
816 | ||
a79316c6 | 817 | metadata_access_enable(); |
79824820 | 818 | fault = memchr_inv(end - remainder, POISON_INUSE, remainder); |
a79316c6 | 819 | metadata_access_disable(); |
24922684 CL |
820 | if (!fault) |
821 | return 1; | |
822 | while (end > fault && end[-1] == POISON_INUSE) | |
823 | end--; | |
824 | ||
825 | slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); | |
ffc79d28 | 826 | print_section("Padding ", end - remainder, remainder); |
24922684 | 827 | |
8a3d271d | 828 | restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end); |
24922684 | 829 | return 0; |
81819f0f CL |
830 | } |
831 | ||
832 | static int check_object(struct kmem_cache *s, struct page *page, | |
f7cb1933 | 833 | void *object, u8 val) |
81819f0f CL |
834 | { |
835 | u8 *p = object; | |
3b0efdfa | 836 | u8 *endobject = object + s->object_size; |
81819f0f CL |
837 | |
838 | if (s->flags & SLAB_RED_ZONE) { | |
d86bd1be JK |
839 | if (!check_bytes_and_report(s, page, object, "Redzone", |
840 | object - s->red_left_pad, val, s->red_left_pad)) | |
841 | return 0; | |
842 | ||
24922684 | 843 | if (!check_bytes_and_report(s, page, object, "Redzone", |
3b0efdfa | 844 | endobject, val, s->inuse - s->object_size)) |
81819f0f | 845 | return 0; |
81819f0f | 846 | } else { |
3b0efdfa | 847 | if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { |
3adbefee | 848 | check_bytes_and_report(s, page, p, "Alignment padding", |
d0e0ac97 CG |
849 | endobject, POISON_INUSE, |
850 | s->inuse - s->object_size); | |
3adbefee | 851 | } |
81819f0f CL |
852 | } |
853 | ||
854 | if (s->flags & SLAB_POISON) { | |
f7cb1933 | 855 | if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && |
24922684 | 856 | (!check_bytes_and_report(s, page, p, "Poison", p, |
3b0efdfa | 857 | POISON_FREE, s->object_size - 1) || |
24922684 | 858 | !check_bytes_and_report(s, page, p, "Poison", |
3b0efdfa | 859 | p + s->object_size - 1, POISON_END, 1))) |
81819f0f | 860 | return 0; |
81819f0f CL |
861 | /* |
862 | * check_pad_bytes cleans up on its own. | |
863 | */ | |
864 | check_pad_bytes(s, page, p); | |
865 | } | |
866 | ||
f7cb1933 | 867 | if (!s->offset && val == SLUB_RED_ACTIVE) |
81819f0f CL |
868 | /* |
869 | * Object and freepointer overlap. Cannot check | |
870 | * freepointer while object is allocated. | |
871 | */ | |
872 | return 1; | |
873 | ||
874 | /* Check free pointer validity */ | |
875 | if (!check_valid_pointer(s, page, get_freepointer(s, p))) { | |
876 | object_err(s, page, p, "Freepointer corrupt"); | |
877 | /* | |
9f6c708e | 878 | * No choice but to zap it and thus lose the remainder |
81819f0f | 879 | * of the free objects in this slab. May cause |
672bba3a | 880 | * another error because the object count is now wrong. |
81819f0f | 881 | */ |
a973e9dd | 882 | set_freepointer(s, p, NULL); |
81819f0f CL |
883 | return 0; |
884 | } | |
885 | return 1; | |
886 | } | |
887 | ||
888 | static int check_slab(struct kmem_cache *s, struct page *page) | |
889 | { | |
39b26464 CL |
890 | int maxobj; |
891 | ||
81819f0f CL |
892 | VM_BUG_ON(!irqs_disabled()); |
893 | ||
894 | if (!PageSlab(page)) { | |
24922684 | 895 | slab_err(s, page, "Not a valid slab page"); |
81819f0f CL |
896 | return 0; |
897 | } | |
39b26464 | 898 | |
ab9a0f19 | 899 | maxobj = order_objects(compound_order(page), s->size, s->reserved); |
39b26464 CL |
900 | if (page->objects > maxobj) { |
901 | slab_err(s, page, "objects %u > max %u", | |
f6edde9c | 902 | page->objects, maxobj); |
39b26464 CL |
903 | return 0; |
904 | } | |
905 | if (page->inuse > page->objects) { | |
24922684 | 906 | slab_err(s, page, "inuse %u > max %u", |
f6edde9c | 907 | page->inuse, page->objects); |
81819f0f CL |
908 | return 0; |
909 | } | |
910 | /* Slab_pad_check fixes things up after itself */ | |
911 | slab_pad_check(s, page); | |
912 | return 1; | |
913 | } | |
914 | ||
915 | /* | |
672bba3a CL |
916 | * Determine if a certain object on a page is on the freelist. Must hold the |
917 | * slab lock to guarantee that the chains are in a consistent state. | |
81819f0f CL |
918 | */ |
919 | static int on_freelist(struct kmem_cache *s, struct page *page, void *search) | |
920 | { | |
921 | int nr = 0; | |
881db7fb | 922 | void *fp; |
81819f0f | 923 | void *object = NULL; |
f6edde9c | 924 | int max_objects; |
81819f0f | 925 | |
881db7fb | 926 | fp = page->freelist; |
39b26464 | 927 | while (fp && nr <= page->objects) { |
81819f0f CL |
928 | if (fp == search) |
929 | return 1; | |
930 | if (!check_valid_pointer(s, page, fp)) { | |
931 | if (object) { | |
932 | object_err(s, page, object, | |
933 | "Freechain corrupt"); | |
a973e9dd | 934 | set_freepointer(s, object, NULL); |
81819f0f | 935 | } else { |
24922684 | 936 | slab_err(s, page, "Freepointer corrupt"); |
a973e9dd | 937 | page->freelist = NULL; |
39b26464 | 938 | page->inuse = page->objects; |
24922684 | 939 | slab_fix(s, "Freelist cleared"); |
81819f0f CL |
940 | return 0; |
941 | } | |
942 | break; | |
943 | } | |
944 | object = fp; | |
945 | fp = get_freepointer(s, object); | |
946 | nr++; | |
947 | } | |
948 | ||
ab9a0f19 | 949 | max_objects = order_objects(compound_order(page), s->size, s->reserved); |
210b5c06 CG |
950 | if (max_objects > MAX_OBJS_PER_PAGE) |
951 | max_objects = MAX_OBJS_PER_PAGE; | |
224a88be CL |
952 | |
953 | if (page->objects != max_objects) { | |
954 | slab_err(s, page, "Wrong number of objects. Found %d but " | |
955 | "should be %d", page->objects, max_objects); | |
956 | page->objects = max_objects; | |
957 | slab_fix(s, "Number of objects adjusted."); | |
958 | } | |
39b26464 | 959 | if (page->inuse != page->objects - nr) { |
70d71228 | 960 | slab_err(s, page, "Wrong object count. Counter is %d but " |
39b26464 CL |
961 | "counted were %d", page->inuse, page->objects - nr); |
962 | page->inuse = page->objects - nr; | |
24922684 | 963 | slab_fix(s, "Object count adjusted."); |
81819f0f CL |
964 | } |
965 | return search == NULL; | |
966 | } | |
967 | ||
0121c619 CL |
968 | static void trace(struct kmem_cache *s, struct page *page, void *object, |
969 | int alloc) | |
3ec09742 CL |
970 | { |
971 | if (s->flags & SLAB_TRACE) { | |
f9f58285 | 972 | pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", |
3ec09742 CL |
973 | s->name, |
974 | alloc ? "alloc" : "free", | |
975 | object, page->inuse, | |
976 | page->freelist); | |
977 | ||
978 | if (!alloc) | |
d0e0ac97 CG |
979 | print_section("Object ", (void *)object, |
980 | s->object_size); | |
3ec09742 CL |
981 | |
982 | dump_stack(); | |
983 | } | |
984 | } | |
985 | ||
643b1138 | 986 | /* |
672bba3a | 987 | * Tracking of fully allocated slabs for debugging purposes. |
643b1138 | 988 | */ |
5cc6eee8 CL |
989 | static void add_full(struct kmem_cache *s, |
990 | struct kmem_cache_node *n, struct page *page) | |
643b1138 | 991 | { |
5cc6eee8 CL |
992 | if (!(s->flags & SLAB_STORE_USER)) |
993 | return; | |
994 | ||
255d0884 | 995 | lockdep_assert_held(&n->list_lock); |
643b1138 | 996 | list_add(&page->lru, &n->full); |
643b1138 CL |
997 | } |
998 | ||
c65c1877 | 999 | static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct page *page) |
643b1138 | 1000 | { |
643b1138 CL |
1001 | if (!(s->flags & SLAB_STORE_USER)) |
1002 | return; | |
1003 | ||
255d0884 | 1004 | lockdep_assert_held(&n->list_lock); |
643b1138 | 1005 | list_del(&page->lru); |
643b1138 CL |
1006 | } |
1007 | ||
0f389ec6 CL |
1008 | /* Tracking of the number of slabs for debugging purposes */ |
1009 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) | |
1010 | { | |
1011 | struct kmem_cache_node *n = get_node(s, node); | |
1012 | ||
1013 | return atomic_long_read(&n->nr_slabs); | |
1014 | } | |
1015 | ||
26c02cf0 AB |
1016 | static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) |
1017 | { | |
1018 | return atomic_long_read(&n->nr_slabs); | |
1019 | } | |
1020 | ||
205ab99d | 1021 | static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
1022 | { |
1023 | struct kmem_cache_node *n = get_node(s, node); | |
1024 | ||
1025 | /* | |
1026 | * May be called early in order to allocate a slab for the | |
1027 | * kmem_cache_node structure. Solve the chicken-egg | |
1028 | * dilemma by deferring the increment of the count during | |
1029 | * bootstrap (see early_kmem_cache_node_alloc). | |
1030 | */ | |
338b2642 | 1031 | if (likely(n)) { |
0f389ec6 | 1032 | atomic_long_inc(&n->nr_slabs); |
205ab99d CL |
1033 | atomic_long_add(objects, &n->total_objects); |
1034 | } | |
0f389ec6 | 1035 | } |
205ab99d | 1036 | static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
1037 | { |
1038 | struct kmem_cache_node *n = get_node(s, node); | |
1039 | ||
1040 | atomic_long_dec(&n->nr_slabs); | |
205ab99d | 1041 | atomic_long_sub(objects, &n->total_objects); |
0f389ec6 CL |
1042 | } |
1043 | ||
1044 | /* Object debug checks for alloc/free paths */ | |
3ec09742 CL |
1045 | static void setup_object_debug(struct kmem_cache *s, struct page *page, |
1046 | void *object) | |
1047 | { | |
1048 | if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON))) | |
1049 | return; | |
1050 | ||
f7cb1933 | 1051 | init_object(s, object, SLUB_RED_INACTIVE); |
3ec09742 CL |
1052 | init_tracking(s, object); |
1053 | } | |
1054 | ||
becfda68 | 1055 | static inline int alloc_consistency_checks(struct kmem_cache *s, |
d0e0ac97 | 1056 | struct page *page, |
ce71e27c | 1057 | void *object, unsigned long addr) |
81819f0f CL |
1058 | { |
1059 | if (!check_slab(s, page)) | |
becfda68 | 1060 | return 0; |
81819f0f | 1061 | |
81819f0f CL |
1062 | if (!check_valid_pointer(s, page, object)) { |
1063 | object_err(s, page, object, "Freelist Pointer check fails"); | |
becfda68 | 1064 | return 0; |
81819f0f CL |
1065 | } |
1066 | ||
f7cb1933 | 1067 | if (!check_object(s, page, object, SLUB_RED_INACTIVE)) |
becfda68 LA |
1068 | return 0; |
1069 | ||
1070 | return 1; | |
1071 | } | |
1072 | ||
1073 | static noinline int alloc_debug_processing(struct kmem_cache *s, | |
1074 | struct page *page, | |
1075 | void *object, unsigned long addr) | |
1076 | { | |
1077 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { | |
1078 | if (!alloc_consistency_checks(s, page, object, addr)) | |
1079 | goto bad; | |
1080 | } | |
81819f0f | 1081 | |
3ec09742 CL |
1082 | /* Success perform special debug activities for allocs */ |
1083 | if (s->flags & SLAB_STORE_USER) | |
1084 | set_track(s, object, TRACK_ALLOC, addr); | |
1085 | trace(s, page, object, 1); | |
f7cb1933 | 1086 | init_object(s, object, SLUB_RED_ACTIVE); |
81819f0f | 1087 | return 1; |
3ec09742 | 1088 | |
81819f0f CL |
1089 | bad: |
1090 | if (PageSlab(page)) { | |
1091 | /* | |
1092 | * If this is a slab page then lets do the best we can | |
1093 | * to avoid issues in the future. Marking all objects | |
672bba3a | 1094 | * as used avoids touching the remaining objects. |
81819f0f | 1095 | */ |
24922684 | 1096 | slab_fix(s, "Marking all objects used"); |
39b26464 | 1097 | page->inuse = page->objects; |
a973e9dd | 1098 | page->freelist = NULL; |
81819f0f CL |
1099 | } |
1100 | return 0; | |
1101 | } | |
1102 | ||
becfda68 LA |
1103 | static inline int free_consistency_checks(struct kmem_cache *s, |
1104 | struct page *page, void *object, unsigned long addr) | |
81819f0f | 1105 | { |
81819f0f | 1106 | if (!check_valid_pointer(s, page, object)) { |
70d71228 | 1107 | slab_err(s, page, "Invalid object pointer 0x%p", object); |
becfda68 | 1108 | return 0; |
81819f0f CL |
1109 | } |
1110 | ||
1111 | if (on_freelist(s, page, object)) { | |
24922684 | 1112 | object_err(s, page, object, "Object already free"); |
becfda68 | 1113 | return 0; |
81819f0f CL |
1114 | } |
1115 | ||
f7cb1933 | 1116 | if (!check_object(s, page, object, SLUB_RED_ACTIVE)) |
becfda68 | 1117 | return 0; |
81819f0f | 1118 | |
1b4f59e3 | 1119 | if (unlikely(s != page->slab_cache)) { |
3adbefee | 1120 | if (!PageSlab(page)) { |
70d71228 CL |
1121 | slab_err(s, page, "Attempt to free object(0x%p) " |
1122 | "outside of slab", object); | |
1b4f59e3 | 1123 | } else if (!page->slab_cache) { |
f9f58285 FF |
1124 | pr_err("SLUB <none>: no slab for object 0x%p.\n", |
1125 | object); | |
70d71228 | 1126 | dump_stack(); |
06428780 | 1127 | } else |
24922684 CL |
1128 | object_err(s, page, object, |
1129 | "page slab pointer corrupt."); | |
becfda68 LA |
1130 | return 0; |
1131 | } | |
1132 | return 1; | |
1133 | } | |
1134 | ||
1135 | /* Supports checking bulk free of a constructed freelist */ | |
1136 | static noinline int free_debug_processing( | |
1137 | struct kmem_cache *s, struct page *page, | |
1138 | void *head, void *tail, int bulk_cnt, | |
1139 | unsigned long addr) | |
1140 | { | |
1141 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); | |
1142 | void *object = head; | |
1143 | int cnt = 0; | |
1144 | unsigned long uninitialized_var(flags); | |
1145 | int ret = 0; | |
1146 | ||
1147 | spin_lock_irqsave(&n->list_lock, flags); | |
1148 | slab_lock(page); | |
1149 | ||
1150 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { | |
1151 | if (!check_slab(s, page)) | |
1152 | goto out; | |
1153 | } | |
1154 | ||
1155 | next_object: | |
1156 | cnt++; | |
1157 | ||
1158 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { | |
1159 | if (!free_consistency_checks(s, page, object, addr)) | |
1160 | goto out; | |
81819f0f | 1161 | } |
3ec09742 | 1162 | |
3ec09742 CL |
1163 | if (s->flags & SLAB_STORE_USER) |
1164 | set_track(s, object, TRACK_FREE, addr); | |
1165 | trace(s, page, object, 0); | |
81084651 | 1166 | /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ |
f7cb1933 | 1167 | init_object(s, object, SLUB_RED_INACTIVE); |
81084651 JDB |
1168 | |
1169 | /* Reached end of constructed freelist yet? */ | |
1170 | if (object != tail) { | |
1171 | object = get_freepointer(s, object); | |
1172 | goto next_object; | |
1173 | } | |
804aa132 LA |
1174 | ret = 1; |
1175 | ||
5c2e4bbb | 1176 | out: |
81084651 JDB |
1177 | if (cnt != bulk_cnt) |
1178 | slab_err(s, page, "Bulk freelist count(%d) invalid(%d)\n", | |
1179 | bulk_cnt, cnt); | |
1180 | ||
881db7fb | 1181 | slab_unlock(page); |
282acb43 | 1182 | spin_unlock_irqrestore(&n->list_lock, flags); |
804aa132 LA |
1183 | if (!ret) |
1184 | slab_fix(s, "Object at 0x%p not freed", object); | |
1185 | return ret; | |
81819f0f CL |
1186 | } |
1187 | ||
41ecc55b CL |
1188 | static int __init setup_slub_debug(char *str) |
1189 | { | |
f0630fff CL |
1190 | slub_debug = DEBUG_DEFAULT_FLAGS; |
1191 | if (*str++ != '=' || !*str) | |
1192 | /* | |
1193 | * No options specified. Switch on full debugging. | |
1194 | */ | |
1195 | goto out; | |
1196 | ||
1197 | if (*str == ',') | |
1198 | /* | |
1199 | * No options but restriction on slabs. This means full | |
1200 | * debugging for slabs matching a pattern. | |
1201 | */ | |
1202 | goto check_slabs; | |
1203 | ||
1204 | slub_debug = 0; | |
1205 | if (*str == '-') | |
1206 | /* | |
1207 | * Switch off all debugging measures. | |
1208 | */ | |
1209 | goto out; | |
1210 | ||
1211 | /* | |
1212 | * Determine which debug features should be switched on | |
1213 | */ | |
06428780 | 1214 | for (; *str && *str != ','; str++) { |
f0630fff CL |
1215 | switch (tolower(*str)) { |
1216 | case 'f': | |
becfda68 | 1217 | slub_debug |= SLAB_CONSISTENCY_CHECKS; |
f0630fff CL |
1218 | break; |
1219 | case 'z': | |
1220 | slub_debug |= SLAB_RED_ZONE; | |
1221 | break; | |
1222 | case 'p': | |
1223 | slub_debug |= SLAB_POISON; | |
1224 | break; | |
1225 | case 'u': | |
1226 | slub_debug |= SLAB_STORE_USER; | |
1227 | break; | |
1228 | case 't': | |
1229 | slub_debug |= SLAB_TRACE; | |
1230 | break; | |
4c13dd3b DM |
1231 | case 'a': |
1232 | slub_debug |= SLAB_FAILSLAB; | |
1233 | break; | |
08303a73 CA |
1234 | case 'o': |
1235 | /* | |
1236 | * Avoid enabling debugging on caches if its minimum | |
1237 | * order would increase as a result. | |
1238 | */ | |
1239 | disable_higher_order_debug = 1; | |
1240 | break; | |
f0630fff | 1241 | default: |
f9f58285 FF |
1242 | pr_err("slub_debug option '%c' unknown. skipped\n", |
1243 | *str); | |
f0630fff | 1244 | } |
41ecc55b CL |
1245 | } |
1246 | ||
f0630fff | 1247 | check_slabs: |
41ecc55b CL |
1248 | if (*str == ',') |
1249 | slub_debug_slabs = str + 1; | |
f0630fff | 1250 | out: |
41ecc55b CL |
1251 | return 1; |
1252 | } | |
1253 | ||
1254 | __setup("slub_debug", setup_slub_debug); | |
1255 | ||
423c929c | 1256 | unsigned long kmem_cache_flags(unsigned long object_size, |
ba0268a8 | 1257 | unsigned long flags, const char *name, |
51cc5068 | 1258 | void (*ctor)(void *)) |
41ecc55b CL |
1259 | { |
1260 | /* | |
e153362a | 1261 | * Enable debugging if selected on the kernel commandline. |
41ecc55b | 1262 | */ |
c6f58d9b CL |
1263 | if (slub_debug && (!slub_debug_slabs || (name && |
1264 | !strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs))))) | |
3de47213 | 1265 | flags |= slub_debug; |
ba0268a8 CL |
1266 | |
1267 | return flags; | |
41ecc55b | 1268 | } |
b4a64718 | 1269 | #else /* !CONFIG_SLUB_DEBUG */ |
3ec09742 CL |
1270 | static inline void setup_object_debug(struct kmem_cache *s, |
1271 | struct page *page, void *object) {} | |
41ecc55b | 1272 | |
3ec09742 | 1273 | static inline int alloc_debug_processing(struct kmem_cache *s, |
ce71e27c | 1274 | struct page *page, void *object, unsigned long addr) { return 0; } |
41ecc55b | 1275 | |
282acb43 | 1276 | static inline int free_debug_processing( |
81084651 JDB |
1277 | struct kmem_cache *s, struct page *page, |
1278 | void *head, void *tail, int bulk_cnt, | |
282acb43 | 1279 | unsigned long addr) { return 0; } |
41ecc55b | 1280 | |
41ecc55b CL |
1281 | static inline int slab_pad_check(struct kmem_cache *s, struct page *page) |
1282 | { return 1; } | |
1283 | static inline int check_object(struct kmem_cache *s, struct page *page, | |
f7cb1933 | 1284 | void *object, u8 val) { return 1; } |
5cc6eee8 CL |
1285 | static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, |
1286 | struct page *page) {} | |
c65c1877 PZ |
1287 | static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, |
1288 | struct page *page) {} | |
423c929c | 1289 | unsigned long kmem_cache_flags(unsigned long object_size, |
ba0268a8 | 1290 | unsigned long flags, const char *name, |
51cc5068 | 1291 | void (*ctor)(void *)) |
ba0268a8 CL |
1292 | { |
1293 | return flags; | |
1294 | } | |
41ecc55b | 1295 | #define slub_debug 0 |
0f389ec6 | 1296 | |
fdaa45e9 IM |
1297 | #define disable_higher_order_debug 0 |
1298 | ||
0f389ec6 CL |
1299 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) |
1300 | { return 0; } | |
26c02cf0 AB |
1301 | static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) |
1302 | { return 0; } | |
205ab99d CL |
1303 | static inline void inc_slabs_node(struct kmem_cache *s, int node, |
1304 | int objects) {} | |
1305 | static inline void dec_slabs_node(struct kmem_cache *s, int node, | |
1306 | int objects) {} | |
7d550c56 | 1307 | |
02e72cc6 AR |
1308 | #endif /* CONFIG_SLUB_DEBUG */ |
1309 | ||
1310 | /* | |
1311 | * Hooks for other subsystems that check memory allocations. In a typical | |
1312 | * production configuration these hooks all should produce no code at all. | |
1313 | */ | |
d56791b3 RB |
1314 | static inline void kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags) |
1315 | { | |
1316 | kmemleak_alloc(ptr, size, 1, flags); | |
0316bec2 | 1317 | kasan_kmalloc_large(ptr, size); |
d56791b3 RB |
1318 | } |
1319 | ||
1320 | static inline void kfree_hook(const void *x) | |
1321 | { | |
1322 | kmemleak_free(x); | |
0316bec2 | 1323 | kasan_kfree_large(x); |
d56791b3 RB |
1324 | } |
1325 | ||
d56791b3 RB |
1326 | static inline void slab_free_hook(struct kmem_cache *s, void *x) |
1327 | { | |
1328 | kmemleak_free_recursive(x, s->flags); | |
7d550c56 | 1329 | |
02e72cc6 AR |
1330 | /* |
1331 | * Trouble is that we may no longer disable interrupts in the fast path | |
1332 | * So in order to make the debug calls that expect irqs to be | |
1333 | * disabled we need to disable interrupts temporarily. | |
1334 | */ | |
1335 | #if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP) | |
1336 | { | |
1337 | unsigned long flags; | |
1338 | ||
1339 | local_irq_save(flags); | |
1340 | kmemcheck_slab_free(s, x, s->object_size); | |
1341 | debug_check_no_locks_freed(x, s->object_size); | |
1342 | local_irq_restore(flags); | |
1343 | } | |
1344 | #endif | |
1345 | if (!(s->flags & SLAB_DEBUG_OBJECTS)) | |
1346 | debug_check_no_obj_freed(x, s->object_size); | |
0316bec2 AR |
1347 | |
1348 | kasan_slab_free(s, x); | |
02e72cc6 | 1349 | } |
205ab99d | 1350 | |
81084651 JDB |
1351 | static inline void slab_free_freelist_hook(struct kmem_cache *s, |
1352 | void *head, void *tail) | |
1353 | { | |
1354 | /* | |
1355 | * Compiler cannot detect this function can be removed if slab_free_hook() | |
1356 | * evaluates to nothing. Thus, catch all relevant config debug options here. | |
1357 | */ | |
1358 | #if defined(CONFIG_KMEMCHECK) || \ | |
1359 | defined(CONFIG_LOCKDEP) || \ | |
1360 | defined(CONFIG_DEBUG_KMEMLEAK) || \ | |
1361 | defined(CONFIG_DEBUG_OBJECTS_FREE) || \ | |
1362 | defined(CONFIG_KASAN) | |
1363 | ||
1364 | void *object = head; | |
1365 | void *tail_obj = tail ? : head; | |
1366 | ||
1367 | do { | |
1368 | slab_free_hook(s, object); | |
1369 | } while ((object != tail_obj) && | |
1370 | (object = get_freepointer(s, object))); | |
1371 | #endif | |
1372 | } | |
1373 | ||
588f8ba9 TG |
1374 | static void setup_object(struct kmem_cache *s, struct page *page, |
1375 | void *object) | |
1376 | { | |
1377 | setup_object_debug(s, page, object); | |
1378 | if (unlikely(s->ctor)) { | |
1379 | kasan_unpoison_object_data(s, object); | |
1380 | s->ctor(object); | |
1381 | kasan_poison_object_data(s, object); | |
1382 | } | |
1383 | } | |
1384 | ||
81819f0f CL |
1385 | /* |
1386 | * Slab allocation and freeing | |
1387 | */ | |
5dfb4175 VD |
1388 | static inline struct page *alloc_slab_page(struct kmem_cache *s, |
1389 | gfp_t flags, int node, struct kmem_cache_order_objects oo) | |
65c3376a | 1390 | { |
5dfb4175 | 1391 | struct page *page; |
65c3376a CL |
1392 | int order = oo_order(oo); |
1393 | ||
b1eeab67 VN |
1394 | flags |= __GFP_NOTRACK; |
1395 | ||
2154a336 | 1396 | if (node == NUMA_NO_NODE) |
5dfb4175 | 1397 | page = alloc_pages(flags, order); |
65c3376a | 1398 | else |
96db800f | 1399 | page = __alloc_pages_node(node, flags, order); |
5dfb4175 | 1400 | |
f3ccb2c4 VD |
1401 | if (page && memcg_charge_slab(page, flags, order, s)) { |
1402 | __free_pages(page, order); | |
1403 | page = NULL; | |
1404 | } | |
5dfb4175 VD |
1405 | |
1406 | return page; | |
65c3376a CL |
1407 | } |
1408 | ||
81819f0f CL |
1409 | static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) |
1410 | { | |
06428780 | 1411 | struct page *page; |
834f3d11 | 1412 | struct kmem_cache_order_objects oo = s->oo; |
ba52270d | 1413 | gfp_t alloc_gfp; |
588f8ba9 TG |
1414 | void *start, *p; |
1415 | int idx, order; | |
81819f0f | 1416 | |
7e0528da CL |
1417 | flags &= gfp_allowed_mask; |
1418 | ||
d0164adc | 1419 | if (gfpflags_allow_blocking(flags)) |
7e0528da CL |
1420 | local_irq_enable(); |
1421 | ||
b7a49f0d | 1422 | flags |= s->allocflags; |
e12ba74d | 1423 | |
ba52270d PE |
1424 | /* |
1425 | * Let the initial higher-order allocation fail under memory pressure | |
1426 | * so we fall-back to the minimum order allocation. | |
1427 | */ | |
1428 | alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; | |
d0164adc MG |
1429 | if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) |
1430 | alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~__GFP_DIRECT_RECLAIM; | |
ba52270d | 1431 | |
5dfb4175 | 1432 | page = alloc_slab_page(s, alloc_gfp, node, oo); |
65c3376a CL |
1433 | if (unlikely(!page)) { |
1434 | oo = s->min; | |
80c3a998 | 1435 | alloc_gfp = flags; |
65c3376a CL |
1436 | /* |
1437 | * Allocation may have failed due to fragmentation. | |
1438 | * Try a lower order alloc if possible | |
1439 | */ | |
5dfb4175 | 1440 | page = alloc_slab_page(s, alloc_gfp, node, oo); |
588f8ba9 TG |
1441 | if (unlikely(!page)) |
1442 | goto out; | |
1443 | stat(s, ORDER_FALLBACK); | |
65c3376a | 1444 | } |
5a896d9e | 1445 | |
588f8ba9 TG |
1446 | if (kmemcheck_enabled && |
1447 | !(s->flags & (SLAB_NOTRACK | DEBUG_DEFAULT_FLAGS))) { | |
b1eeab67 VN |
1448 | int pages = 1 << oo_order(oo); |
1449 | ||
80c3a998 | 1450 | kmemcheck_alloc_shadow(page, oo_order(oo), alloc_gfp, node); |
b1eeab67 VN |
1451 | |
1452 | /* | |
1453 | * Objects from caches that have a constructor don't get | |
1454 | * cleared when they're allocated, so we need to do it here. | |
1455 | */ | |
1456 | if (s->ctor) | |
1457 | kmemcheck_mark_uninitialized_pages(page, pages); | |
1458 | else | |
1459 | kmemcheck_mark_unallocated_pages(page, pages); | |
5a896d9e VN |
1460 | } |
1461 | ||
834f3d11 | 1462 | page->objects = oo_objects(oo); |
81819f0f | 1463 | |
1f458cbf | 1464 | order = compound_order(page); |
1b4f59e3 | 1465 | page->slab_cache = s; |
c03f94cc | 1466 | __SetPageSlab(page); |
2f064f34 | 1467 | if (page_is_pfmemalloc(page)) |
072bb0aa | 1468 | SetPageSlabPfmemalloc(page); |
81819f0f CL |
1469 | |
1470 | start = page_address(page); | |
81819f0f CL |
1471 | |
1472 | if (unlikely(s->flags & SLAB_POISON)) | |
1f458cbf | 1473 | memset(start, POISON_INUSE, PAGE_SIZE << order); |
81819f0f | 1474 | |
0316bec2 AR |
1475 | kasan_poison_slab(page); |
1476 | ||
54266640 WY |
1477 | for_each_object_idx(p, idx, s, start, page->objects) { |
1478 | setup_object(s, page, p); | |
1479 | if (likely(idx < page->objects)) | |
1480 | set_freepointer(s, p, p + s->size); | |
1481 | else | |
1482 | set_freepointer(s, p, NULL); | |
81819f0f | 1483 | } |
81819f0f | 1484 | |
d86bd1be | 1485 | page->freelist = fixup_red_left(s, start); |
e6e82ea1 | 1486 | page->inuse = page->objects; |
8cb0a506 | 1487 | page->frozen = 1; |
588f8ba9 | 1488 | |
81819f0f | 1489 | out: |
d0164adc | 1490 | if (gfpflags_allow_blocking(flags)) |
588f8ba9 TG |
1491 | local_irq_disable(); |
1492 | if (!page) | |
1493 | return NULL; | |
1494 | ||
1495 | mod_zone_page_state(page_zone(page), | |
1496 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? | |
1497 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
1498 | 1 << oo_order(oo)); | |
1499 | ||
1500 | inc_slabs_node(s, page_to_nid(page), page->objects); | |
1501 | ||
81819f0f CL |
1502 | return page; |
1503 | } | |
1504 | ||
588f8ba9 TG |
1505 | static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) |
1506 | { | |
1507 | if (unlikely(flags & GFP_SLAB_BUG_MASK)) { | |
1508 | pr_emerg("gfp: %u\n", flags & GFP_SLAB_BUG_MASK); | |
1509 | BUG(); | |
1510 | } | |
1511 | ||
1512 | return allocate_slab(s, | |
1513 | flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); | |
1514 | } | |
1515 | ||
81819f0f CL |
1516 | static void __free_slab(struct kmem_cache *s, struct page *page) |
1517 | { | |
834f3d11 CL |
1518 | int order = compound_order(page); |
1519 | int pages = 1 << order; | |
81819f0f | 1520 | |
becfda68 | 1521 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { |
81819f0f CL |
1522 | void *p; |
1523 | ||
1524 | slab_pad_check(s, page); | |
224a88be CL |
1525 | for_each_object(p, s, page_address(page), |
1526 | page->objects) | |
f7cb1933 | 1527 | check_object(s, page, p, SLUB_RED_INACTIVE); |
81819f0f CL |
1528 | } |
1529 | ||
b1eeab67 | 1530 | kmemcheck_free_shadow(page, compound_order(page)); |
5a896d9e | 1531 | |
81819f0f CL |
1532 | mod_zone_page_state(page_zone(page), |
1533 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? | |
1534 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
06428780 | 1535 | -pages); |
81819f0f | 1536 | |
072bb0aa | 1537 | __ClearPageSlabPfmemalloc(page); |
49bd5221 | 1538 | __ClearPageSlab(page); |
1f458cbf | 1539 | |
22b751c3 | 1540 | page_mapcount_reset(page); |
1eb5ac64 NP |
1541 | if (current->reclaim_state) |
1542 | current->reclaim_state->reclaimed_slab += pages; | |
27ee57c9 VD |
1543 | memcg_uncharge_slab(page, order, s); |
1544 | __free_pages(page, order); | |
81819f0f CL |
1545 | } |
1546 | ||
da9a638c LJ |
1547 | #define need_reserve_slab_rcu \ |
1548 | (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head)) | |
1549 | ||
81819f0f CL |
1550 | static void rcu_free_slab(struct rcu_head *h) |
1551 | { | |
1552 | struct page *page; | |
1553 | ||
da9a638c LJ |
1554 | if (need_reserve_slab_rcu) |
1555 | page = virt_to_head_page(h); | |
1556 | else | |
1557 | page = container_of((struct list_head *)h, struct page, lru); | |
1558 | ||
1b4f59e3 | 1559 | __free_slab(page->slab_cache, page); |
81819f0f CL |
1560 | } |
1561 | ||
1562 | static void free_slab(struct kmem_cache *s, struct page *page) | |
1563 | { | |
1564 | if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) { | |
da9a638c LJ |
1565 | struct rcu_head *head; |
1566 | ||
1567 | if (need_reserve_slab_rcu) { | |
1568 | int order = compound_order(page); | |
1569 | int offset = (PAGE_SIZE << order) - s->reserved; | |
1570 | ||
1571 | VM_BUG_ON(s->reserved != sizeof(*head)); | |
1572 | head = page_address(page) + offset; | |
1573 | } else { | |
bc4f610d | 1574 | head = &page->rcu_head; |
da9a638c | 1575 | } |
81819f0f CL |
1576 | |
1577 | call_rcu(head, rcu_free_slab); | |
1578 | } else | |
1579 | __free_slab(s, page); | |
1580 | } | |
1581 | ||
1582 | static void discard_slab(struct kmem_cache *s, struct page *page) | |
1583 | { | |
205ab99d | 1584 | dec_slabs_node(s, page_to_nid(page), page->objects); |
81819f0f CL |
1585 | free_slab(s, page); |
1586 | } | |
1587 | ||
1588 | /* | |
5cc6eee8 | 1589 | * Management of partially allocated slabs. |
81819f0f | 1590 | */ |
1e4dd946 SR |
1591 | static inline void |
1592 | __add_partial(struct kmem_cache_node *n, struct page *page, int tail) | |
81819f0f | 1593 | { |
e95eed57 | 1594 | n->nr_partial++; |
136333d1 | 1595 | if (tail == DEACTIVATE_TO_TAIL) |
7c2e132c CL |
1596 | list_add_tail(&page->lru, &n->partial); |
1597 | else | |
1598 | list_add(&page->lru, &n->partial); | |
81819f0f CL |
1599 | } |
1600 | ||
1e4dd946 SR |
1601 | static inline void add_partial(struct kmem_cache_node *n, |
1602 | struct page *page, int tail) | |
62e346a8 | 1603 | { |
c65c1877 | 1604 | lockdep_assert_held(&n->list_lock); |
1e4dd946 SR |
1605 | __add_partial(n, page, tail); |
1606 | } | |
c65c1877 | 1607 | |
1e4dd946 SR |
1608 | static inline void remove_partial(struct kmem_cache_node *n, |
1609 | struct page *page) | |
1610 | { | |
1611 | lockdep_assert_held(&n->list_lock); | |
52b4b950 DS |
1612 | list_del(&page->lru); |
1613 | n->nr_partial--; | |
1e4dd946 SR |
1614 | } |
1615 | ||
81819f0f | 1616 | /* |
7ced3719 CL |
1617 | * Remove slab from the partial list, freeze it and |
1618 | * return the pointer to the freelist. | |
81819f0f | 1619 | * |
497b66f2 | 1620 | * Returns a list of objects or NULL if it fails. |
81819f0f | 1621 | */ |
497b66f2 | 1622 | static inline void *acquire_slab(struct kmem_cache *s, |
acd19fd1 | 1623 | struct kmem_cache_node *n, struct page *page, |
633b0764 | 1624 | int mode, int *objects) |
81819f0f | 1625 | { |
2cfb7455 CL |
1626 | void *freelist; |
1627 | unsigned long counters; | |
1628 | struct page new; | |
1629 | ||
c65c1877 PZ |
1630 | lockdep_assert_held(&n->list_lock); |
1631 | ||
2cfb7455 CL |
1632 | /* |
1633 | * Zap the freelist and set the frozen bit. | |
1634 | * The old freelist is the list of objects for the | |
1635 | * per cpu allocation list. | |
1636 | */ | |
7ced3719 CL |
1637 | freelist = page->freelist; |
1638 | counters = page->counters; | |
1639 | new.counters = counters; | |
633b0764 | 1640 | *objects = new.objects - new.inuse; |
23910c50 | 1641 | if (mode) { |
7ced3719 | 1642 | new.inuse = page->objects; |
23910c50 PE |
1643 | new.freelist = NULL; |
1644 | } else { | |
1645 | new.freelist = freelist; | |
1646 | } | |
2cfb7455 | 1647 | |
a0132ac0 | 1648 | VM_BUG_ON(new.frozen); |
7ced3719 | 1649 | new.frozen = 1; |
2cfb7455 | 1650 | |
7ced3719 | 1651 | if (!__cmpxchg_double_slab(s, page, |
2cfb7455 | 1652 | freelist, counters, |
02d7633f | 1653 | new.freelist, new.counters, |
7ced3719 | 1654 | "acquire_slab")) |
7ced3719 | 1655 | return NULL; |
2cfb7455 CL |
1656 | |
1657 | remove_partial(n, page); | |
7ced3719 | 1658 | WARN_ON(!freelist); |
49e22585 | 1659 | return freelist; |
81819f0f CL |
1660 | } |
1661 | ||
633b0764 | 1662 | static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain); |
8ba00bb6 | 1663 | static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags); |
49e22585 | 1664 | |
81819f0f | 1665 | /* |
672bba3a | 1666 | * Try to allocate a partial slab from a specific node. |
81819f0f | 1667 | */ |
8ba00bb6 JK |
1668 | static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, |
1669 | struct kmem_cache_cpu *c, gfp_t flags) | |
81819f0f | 1670 | { |
49e22585 CL |
1671 | struct page *page, *page2; |
1672 | void *object = NULL; | |
633b0764 JK |
1673 | int available = 0; |
1674 | int objects; | |
81819f0f CL |
1675 | |
1676 | /* | |
1677 | * Racy check. If we mistakenly see no partial slabs then we | |
1678 | * just allocate an empty slab. If we mistakenly try to get a | |
672bba3a CL |
1679 | * partial slab and there is none available then get_partials() |
1680 | * will return NULL. | |
81819f0f CL |
1681 | */ |
1682 | if (!n || !n->nr_partial) | |
1683 | return NULL; | |
1684 | ||
1685 | spin_lock(&n->list_lock); | |
49e22585 | 1686 | list_for_each_entry_safe(page, page2, &n->partial, lru) { |
8ba00bb6 | 1687 | void *t; |
49e22585 | 1688 | |
8ba00bb6 JK |
1689 | if (!pfmemalloc_match(page, flags)) |
1690 | continue; | |
1691 | ||
633b0764 | 1692 | t = acquire_slab(s, n, page, object == NULL, &objects); |
49e22585 CL |
1693 | if (!t) |
1694 | break; | |
1695 | ||
633b0764 | 1696 | available += objects; |
12d79634 | 1697 | if (!object) { |
49e22585 | 1698 | c->page = page; |
49e22585 | 1699 | stat(s, ALLOC_FROM_PARTIAL); |
49e22585 | 1700 | object = t; |
49e22585 | 1701 | } else { |
633b0764 | 1702 | put_cpu_partial(s, page, 0); |
8028dcea | 1703 | stat(s, CPU_PARTIAL_NODE); |
49e22585 | 1704 | } |
345c905d JK |
1705 | if (!kmem_cache_has_cpu_partial(s) |
1706 | || available > s->cpu_partial / 2) | |
49e22585 CL |
1707 | break; |
1708 | ||
497b66f2 | 1709 | } |
81819f0f | 1710 | spin_unlock(&n->list_lock); |
497b66f2 | 1711 | return object; |
81819f0f CL |
1712 | } |
1713 | ||
1714 | /* | |
672bba3a | 1715 | * Get a page from somewhere. Search in increasing NUMA distances. |
81819f0f | 1716 | */ |
de3ec035 | 1717 | static void *get_any_partial(struct kmem_cache *s, gfp_t flags, |
acd19fd1 | 1718 | struct kmem_cache_cpu *c) |
81819f0f CL |
1719 | { |
1720 | #ifdef CONFIG_NUMA | |
1721 | struct zonelist *zonelist; | |
dd1a239f | 1722 | struct zoneref *z; |
54a6eb5c MG |
1723 | struct zone *zone; |
1724 | enum zone_type high_zoneidx = gfp_zone(flags); | |
497b66f2 | 1725 | void *object; |
cc9a6c87 | 1726 | unsigned int cpuset_mems_cookie; |
81819f0f CL |
1727 | |
1728 | /* | |
672bba3a CL |
1729 | * The defrag ratio allows a configuration of the tradeoffs between |
1730 | * inter node defragmentation and node local allocations. A lower | |
1731 | * defrag_ratio increases the tendency to do local allocations | |
1732 | * instead of attempting to obtain partial slabs from other nodes. | |
81819f0f | 1733 | * |
672bba3a CL |
1734 | * If the defrag_ratio is set to 0 then kmalloc() always |
1735 | * returns node local objects. If the ratio is higher then kmalloc() | |
1736 | * may return off node objects because partial slabs are obtained | |
1737 | * from other nodes and filled up. | |
81819f0f | 1738 | * |
6446faa2 | 1739 | * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes |
672bba3a CL |
1740 | * defrag_ratio = 1000) then every (well almost) allocation will |
1741 | * first attempt to defrag slab caches on other nodes. This means | |
1742 | * scanning over all nodes to look for partial slabs which may be | |
1743 | * expensive if we do it every time we are trying to find a slab | |
1744 | * with available objects. | |
81819f0f | 1745 | */ |
9824601e CL |
1746 | if (!s->remote_node_defrag_ratio || |
1747 | get_cycles() % 1024 > s->remote_node_defrag_ratio) | |
81819f0f CL |
1748 | return NULL; |
1749 | ||
cc9a6c87 | 1750 | do { |
d26914d1 | 1751 | cpuset_mems_cookie = read_mems_allowed_begin(); |
2a389610 | 1752 | zonelist = node_zonelist(mempolicy_slab_node(), flags); |
cc9a6c87 MG |
1753 | for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { |
1754 | struct kmem_cache_node *n; | |
1755 | ||
1756 | n = get_node(s, zone_to_nid(zone)); | |
1757 | ||
dee2f8aa | 1758 | if (n && cpuset_zone_allowed(zone, flags) && |
cc9a6c87 | 1759 | n->nr_partial > s->min_partial) { |
8ba00bb6 | 1760 | object = get_partial_node(s, n, c, flags); |
cc9a6c87 MG |
1761 | if (object) { |
1762 | /* | |
d26914d1 MG |
1763 | * Don't check read_mems_allowed_retry() |
1764 | * here - if mems_allowed was updated in | |
1765 | * parallel, that was a harmless race | |
1766 | * between allocation and the cpuset | |
1767 | * update | |
cc9a6c87 | 1768 | */ |
cc9a6c87 MG |
1769 | return object; |
1770 | } | |
c0ff7453 | 1771 | } |
81819f0f | 1772 | } |
d26914d1 | 1773 | } while (read_mems_allowed_retry(cpuset_mems_cookie)); |
81819f0f CL |
1774 | #endif |
1775 | return NULL; | |
1776 | } | |
1777 | ||
1778 | /* | |
1779 | * Get a partial page, lock it and return it. | |
1780 | */ | |
497b66f2 | 1781 | static void *get_partial(struct kmem_cache *s, gfp_t flags, int node, |
acd19fd1 | 1782 | struct kmem_cache_cpu *c) |
81819f0f | 1783 | { |
497b66f2 | 1784 | void *object; |
a561ce00 JK |
1785 | int searchnode = node; |
1786 | ||
1787 | if (node == NUMA_NO_NODE) | |
1788 | searchnode = numa_mem_id(); | |
1789 | else if (!node_present_pages(node)) | |
1790 | searchnode = node_to_mem_node(node); | |
81819f0f | 1791 | |
8ba00bb6 | 1792 | object = get_partial_node(s, get_node(s, searchnode), c, flags); |
497b66f2 CL |
1793 | if (object || node != NUMA_NO_NODE) |
1794 | return object; | |
81819f0f | 1795 | |
acd19fd1 | 1796 | return get_any_partial(s, flags, c); |
81819f0f CL |
1797 | } |
1798 | ||
8a5ec0ba CL |
1799 | #ifdef CONFIG_PREEMPT |
1800 | /* | |
1801 | * Calculate the next globally unique transaction for disambiguiation | |
1802 | * during cmpxchg. The transactions start with the cpu number and are then | |
1803 | * incremented by CONFIG_NR_CPUS. | |
1804 | */ | |
1805 | #define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) | |
1806 | #else | |
1807 | /* | |
1808 | * No preemption supported therefore also no need to check for | |
1809 | * different cpus. | |
1810 | */ | |
1811 | #define TID_STEP 1 | |
1812 | #endif | |
1813 | ||
1814 | static inline unsigned long next_tid(unsigned long tid) | |
1815 | { | |
1816 | return tid + TID_STEP; | |
1817 | } | |
1818 | ||
1819 | static inline unsigned int tid_to_cpu(unsigned long tid) | |
1820 | { | |
1821 | return tid % TID_STEP; | |
1822 | } | |
1823 | ||
1824 | static inline unsigned long tid_to_event(unsigned long tid) | |
1825 | { | |
1826 | return tid / TID_STEP; | |
1827 | } | |
1828 | ||
1829 | static inline unsigned int init_tid(int cpu) | |
1830 | { | |
1831 | return cpu; | |
1832 | } | |
1833 | ||
1834 | static inline void note_cmpxchg_failure(const char *n, | |
1835 | const struct kmem_cache *s, unsigned long tid) | |
1836 | { | |
1837 | #ifdef SLUB_DEBUG_CMPXCHG | |
1838 | unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); | |
1839 | ||
f9f58285 | 1840 | pr_info("%s %s: cmpxchg redo ", n, s->name); |
8a5ec0ba CL |
1841 | |
1842 | #ifdef CONFIG_PREEMPT | |
1843 | if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) | |
f9f58285 | 1844 | pr_warn("due to cpu change %d -> %d\n", |
8a5ec0ba CL |
1845 | tid_to_cpu(tid), tid_to_cpu(actual_tid)); |
1846 | else | |
1847 | #endif | |
1848 | if (tid_to_event(tid) != tid_to_event(actual_tid)) | |
f9f58285 | 1849 | pr_warn("due to cpu running other code. Event %ld->%ld\n", |
8a5ec0ba CL |
1850 | tid_to_event(tid), tid_to_event(actual_tid)); |
1851 | else | |
f9f58285 | 1852 | pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", |
8a5ec0ba CL |
1853 | actual_tid, tid, next_tid(tid)); |
1854 | #endif | |
4fdccdfb | 1855 | stat(s, CMPXCHG_DOUBLE_CPU_FAIL); |
8a5ec0ba CL |
1856 | } |
1857 | ||
788e1aad | 1858 | static void init_kmem_cache_cpus(struct kmem_cache *s) |
8a5ec0ba | 1859 | { |
8a5ec0ba CL |
1860 | int cpu; |
1861 | ||
1862 | for_each_possible_cpu(cpu) | |
1863 | per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu); | |
8a5ec0ba | 1864 | } |
2cfb7455 | 1865 | |
81819f0f CL |
1866 | /* |
1867 | * Remove the cpu slab | |
1868 | */ | |
d0e0ac97 CG |
1869 | static void deactivate_slab(struct kmem_cache *s, struct page *page, |
1870 | void *freelist) | |
81819f0f | 1871 | { |
2cfb7455 | 1872 | enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE }; |
2cfb7455 CL |
1873 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
1874 | int lock = 0; | |
1875 | enum slab_modes l = M_NONE, m = M_NONE; | |
2cfb7455 | 1876 | void *nextfree; |
136333d1 | 1877 | int tail = DEACTIVATE_TO_HEAD; |
2cfb7455 CL |
1878 | struct page new; |
1879 | struct page old; | |
1880 | ||
1881 | if (page->freelist) { | |
84e554e6 | 1882 | stat(s, DEACTIVATE_REMOTE_FREES); |
136333d1 | 1883 | tail = DEACTIVATE_TO_TAIL; |
2cfb7455 CL |
1884 | } |
1885 | ||
894b8788 | 1886 | /* |
2cfb7455 CL |
1887 | * Stage one: Free all available per cpu objects back |
1888 | * to the page freelist while it is still frozen. Leave the | |
1889 | * last one. | |
1890 | * | |
1891 | * There is no need to take the list->lock because the page | |
1892 | * is still frozen. | |
1893 | */ | |
1894 | while (freelist && (nextfree = get_freepointer(s, freelist))) { | |
1895 | void *prior; | |
1896 | unsigned long counters; | |
1897 | ||
1898 | do { | |
1899 | prior = page->freelist; | |
1900 | counters = page->counters; | |
1901 | set_freepointer(s, freelist, prior); | |
1902 | new.counters = counters; | |
1903 | new.inuse--; | |
a0132ac0 | 1904 | VM_BUG_ON(!new.frozen); |
2cfb7455 | 1905 | |
1d07171c | 1906 | } while (!__cmpxchg_double_slab(s, page, |
2cfb7455 CL |
1907 | prior, counters, |
1908 | freelist, new.counters, | |
1909 | "drain percpu freelist")); | |
1910 | ||
1911 | freelist = nextfree; | |
1912 | } | |
1913 | ||
894b8788 | 1914 | /* |
2cfb7455 CL |
1915 | * Stage two: Ensure that the page is unfrozen while the |
1916 | * list presence reflects the actual number of objects | |
1917 | * during unfreeze. | |
1918 | * | |
1919 | * We setup the list membership and then perform a cmpxchg | |
1920 | * with the count. If there is a mismatch then the page | |
1921 | * is not unfrozen but the page is on the wrong list. | |
1922 | * | |
1923 | * Then we restart the process which may have to remove | |
1924 | * the page from the list that we just put it on again | |
1925 | * because the number of objects in the slab may have | |
1926 | * changed. | |
894b8788 | 1927 | */ |
2cfb7455 | 1928 | redo: |
894b8788 | 1929 | |
2cfb7455 CL |
1930 | old.freelist = page->freelist; |
1931 | old.counters = page->counters; | |
a0132ac0 | 1932 | VM_BUG_ON(!old.frozen); |
7c2e132c | 1933 | |
2cfb7455 CL |
1934 | /* Determine target state of the slab */ |
1935 | new.counters = old.counters; | |
1936 | if (freelist) { | |
1937 | new.inuse--; | |
1938 | set_freepointer(s, freelist, old.freelist); | |
1939 | new.freelist = freelist; | |
1940 | } else | |
1941 | new.freelist = old.freelist; | |
1942 | ||
1943 | new.frozen = 0; | |
1944 | ||
8a5b20ae | 1945 | if (!new.inuse && n->nr_partial >= s->min_partial) |
2cfb7455 CL |
1946 | m = M_FREE; |
1947 | else if (new.freelist) { | |
1948 | m = M_PARTIAL; | |
1949 | if (!lock) { | |
1950 | lock = 1; | |
1951 | /* | |
1952 | * Taking the spinlock removes the possiblity | |
1953 | * that acquire_slab() will see a slab page that | |
1954 | * is frozen | |
1955 | */ | |
1956 | spin_lock(&n->list_lock); | |
1957 | } | |
1958 | } else { | |
1959 | m = M_FULL; | |
1960 | if (kmem_cache_debug(s) && !lock) { | |
1961 | lock = 1; | |
1962 | /* | |
1963 | * This also ensures that the scanning of full | |
1964 | * slabs from diagnostic functions will not see | |
1965 | * any frozen slabs. | |
1966 | */ | |
1967 | spin_lock(&n->list_lock); | |
1968 | } | |
1969 | } | |
1970 | ||
1971 | if (l != m) { | |
1972 | ||
1973 | if (l == M_PARTIAL) | |
1974 | ||
1975 | remove_partial(n, page); | |
1976 | ||
1977 | else if (l == M_FULL) | |
894b8788 | 1978 | |
c65c1877 | 1979 | remove_full(s, n, page); |
2cfb7455 CL |
1980 | |
1981 | if (m == M_PARTIAL) { | |
1982 | ||
1983 | add_partial(n, page, tail); | |
136333d1 | 1984 | stat(s, tail); |
2cfb7455 CL |
1985 | |
1986 | } else if (m == M_FULL) { | |
894b8788 | 1987 | |
2cfb7455 CL |
1988 | stat(s, DEACTIVATE_FULL); |
1989 | add_full(s, n, page); | |
1990 | ||
1991 | } | |
1992 | } | |
1993 | ||
1994 | l = m; | |
1d07171c | 1995 | if (!__cmpxchg_double_slab(s, page, |
2cfb7455 CL |
1996 | old.freelist, old.counters, |
1997 | new.freelist, new.counters, | |
1998 | "unfreezing slab")) | |
1999 | goto redo; | |
2000 | ||
2cfb7455 CL |
2001 | if (lock) |
2002 | spin_unlock(&n->list_lock); | |
2003 | ||
2004 | if (m == M_FREE) { | |
2005 | stat(s, DEACTIVATE_EMPTY); | |
2006 | discard_slab(s, page); | |
2007 | stat(s, FREE_SLAB); | |
894b8788 | 2008 | } |
81819f0f CL |
2009 | } |
2010 | ||
d24ac77f JK |
2011 | /* |
2012 | * Unfreeze all the cpu partial slabs. | |
2013 | * | |
59a09917 CL |
2014 | * This function must be called with interrupts disabled |
2015 | * for the cpu using c (or some other guarantee must be there | |
2016 | * to guarantee no concurrent accesses). | |
d24ac77f | 2017 | */ |
59a09917 CL |
2018 | static void unfreeze_partials(struct kmem_cache *s, |
2019 | struct kmem_cache_cpu *c) | |
49e22585 | 2020 | { |
345c905d | 2021 | #ifdef CONFIG_SLUB_CPU_PARTIAL |
43d77867 | 2022 | struct kmem_cache_node *n = NULL, *n2 = NULL; |
9ada1934 | 2023 | struct page *page, *discard_page = NULL; |
49e22585 CL |
2024 | |
2025 | while ((page = c->partial)) { | |
49e22585 CL |
2026 | struct page new; |
2027 | struct page old; | |
2028 | ||
2029 | c->partial = page->next; | |
43d77867 JK |
2030 | |
2031 | n2 = get_node(s, page_to_nid(page)); | |
2032 | if (n != n2) { | |
2033 | if (n) | |
2034 | spin_unlock(&n->list_lock); | |
2035 | ||
2036 | n = n2; | |
2037 | spin_lock(&n->list_lock); | |
2038 | } | |
49e22585 CL |
2039 | |
2040 | do { | |
2041 | ||
2042 | old.freelist = page->freelist; | |
2043 | old.counters = page->counters; | |
a0132ac0 | 2044 | VM_BUG_ON(!old.frozen); |
49e22585 CL |
2045 | |
2046 | new.counters = old.counters; | |
2047 | new.freelist = old.freelist; | |
2048 | ||
2049 | new.frozen = 0; | |
2050 | ||
d24ac77f | 2051 | } while (!__cmpxchg_double_slab(s, page, |
49e22585 CL |
2052 | old.freelist, old.counters, |
2053 | new.freelist, new.counters, | |
2054 | "unfreezing slab")); | |
2055 | ||
8a5b20ae | 2056 | if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { |
9ada1934 SL |
2057 | page->next = discard_page; |
2058 | discard_page = page; | |
43d77867 JK |
2059 | } else { |
2060 | add_partial(n, page, DEACTIVATE_TO_TAIL); | |
2061 | stat(s, FREE_ADD_PARTIAL); | |
49e22585 CL |
2062 | } |
2063 | } | |
2064 | ||
2065 | if (n) | |
2066 | spin_unlock(&n->list_lock); | |
9ada1934 SL |
2067 | |
2068 | while (discard_page) { | |
2069 | page = discard_page; | |
2070 | discard_page = discard_page->next; | |
2071 | ||
2072 | stat(s, DEACTIVATE_EMPTY); | |
2073 | discard_slab(s, page); | |
2074 | stat(s, FREE_SLAB); | |
2075 | } | |
345c905d | 2076 | #endif |
49e22585 CL |
2077 | } |
2078 | ||
2079 | /* | |
2080 | * Put a page that was just frozen (in __slab_free) into a partial page | |
2081 | * slot if available. This is done without interrupts disabled and without | |
2082 | * preemption disabled. The cmpxchg is racy and may put the partial page | |
2083 | * onto a random cpus partial slot. | |
2084 | * | |
2085 | * If we did not find a slot then simply move all the partials to the | |
2086 | * per node partial list. | |
2087 | */ | |
633b0764 | 2088 | static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) |
49e22585 | 2089 | { |
345c905d | 2090 | #ifdef CONFIG_SLUB_CPU_PARTIAL |
49e22585 CL |
2091 | struct page *oldpage; |
2092 | int pages; | |
2093 | int pobjects; | |
2094 | ||
d6e0b7fa | 2095 | preempt_disable(); |
49e22585 CL |
2096 | do { |
2097 | pages = 0; | |
2098 | pobjects = 0; | |
2099 | oldpage = this_cpu_read(s->cpu_slab->partial); | |
2100 | ||
2101 | if (oldpage) { | |
2102 | pobjects = oldpage->pobjects; | |
2103 | pages = oldpage->pages; | |
2104 | if (drain && pobjects > s->cpu_partial) { | |
2105 | unsigned long flags; | |
2106 | /* | |
2107 | * partial array is full. Move the existing | |
2108 | * set to the per node partial list. | |
2109 | */ | |
2110 | local_irq_save(flags); | |
59a09917 | 2111 | unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); |
49e22585 | 2112 | local_irq_restore(flags); |
e24fc410 | 2113 | oldpage = NULL; |
49e22585 CL |
2114 | pobjects = 0; |
2115 | pages = 0; | |
8028dcea | 2116 | stat(s, CPU_PARTIAL_DRAIN); |
49e22585 CL |
2117 | } |
2118 | } | |
2119 | ||
2120 | pages++; | |
2121 | pobjects += page->objects - page->inuse; | |
2122 | ||
2123 | page->pages = pages; | |
2124 | page->pobjects = pobjects; | |
2125 | page->next = oldpage; | |
2126 | ||
d0e0ac97 CG |
2127 | } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) |
2128 | != oldpage); | |
d6e0b7fa VD |
2129 | if (unlikely(!s->cpu_partial)) { |
2130 | unsigned long flags; | |
2131 | ||
2132 | local_irq_save(flags); | |
2133 | unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); | |
2134 | local_irq_restore(flags); | |
2135 | } | |
2136 | preempt_enable(); | |
345c905d | 2137 | #endif |
49e22585 CL |
2138 | } |
2139 | ||
dfb4f096 | 2140 | static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) |
81819f0f | 2141 | { |
84e554e6 | 2142 | stat(s, CPUSLAB_FLUSH); |
c17dda40 CL |
2143 | deactivate_slab(s, c->page, c->freelist); |
2144 | ||
2145 | c->tid = next_tid(c->tid); | |
2146 | c->page = NULL; | |
2147 | c->freelist = NULL; | |
81819f0f CL |
2148 | } |
2149 | ||
2150 | /* | |
2151 | * Flush cpu slab. | |
6446faa2 | 2152 | * |
81819f0f CL |
2153 | * Called from IPI handler with interrupts disabled. |
2154 | */ | |
0c710013 | 2155 | static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) |
81819f0f | 2156 | { |
9dfc6e68 | 2157 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); |
81819f0f | 2158 | |
49e22585 CL |
2159 | if (likely(c)) { |
2160 | if (c->page) | |
2161 | flush_slab(s, c); | |
2162 | ||
59a09917 | 2163 | unfreeze_partials(s, c); |
49e22585 | 2164 | } |
81819f0f CL |
2165 | } |
2166 | ||
2167 | static void flush_cpu_slab(void *d) | |
2168 | { | |
2169 | struct kmem_cache *s = d; | |
81819f0f | 2170 | |
dfb4f096 | 2171 | __flush_cpu_slab(s, smp_processor_id()); |
81819f0f CL |
2172 | } |
2173 | ||
a8364d55 GBY |
2174 | static bool has_cpu_slab(int cpu, void *info) |
2175 | { | |
2176 | struct kmem_cache *s = info; | |
2177 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); | |
2178 | ||
02e1a9cd | 2179 | return c->page || c->partial; |
a8364d55 GBY |
2180 | } |
2181 | ||
81819f0f CL |
2182 | static void flush_all(struct kmem_cache *s) |
2183 | { | |
a8364d55 | 2184 | on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC); |
81819f0f CL |
2185 | } |
2186 | ||
dfb4f096 CL |
2187 | /* |
2188 | * Check if the objects in a per cpu structure fit numa | |
2189 | * locality expectations. | |
2190 | */ | |
57d437d2 | 2191 | static inline int node_match(struct page *page, int node) |
dfb4f096 CL |
2192 | { |
2193 | #ifdef CONFIG_NUMA | |
4d7868e6 | 2194 | if (!page || (node != NUMA_NO_NODE && page_to_nid(page) != node)) |
dfb4f096 CL |
2195 | return 0; |
2196 | #endif | |
2197 | return 1; | |
2198 | } | |
2199 | ||
9a02d699 | 2200 | #ifdef CONFIG_SLUB_DEBUG |
781b2ba6 PE |
2201 | static int count_free(struct page *page) |
2202 | { | |
2203 | return page->objects - page->inuse; | |
2204 | } | |
2205 | ||
9a02d699 DR |
2206 | static inline unsigned long node_nr_objs(struct kmem_cache_node *n) |
2207 | { | |
2208 | return atomic_long_read(&n->total_objects); | |
2209 | } | |
2210 | #endif /* CONFIG_SLUB_DEBUG */ | |
2211 | ||
2212 | #if defined(CONFIG_SLUB_DEBUG) || defined(CONFIG_SYSFS) | |
781b2ba6 PE |
2213 | static unsigned long count_partial(struct kmem_cache_node *n, |
2214 | int (*get_count)(struct page *)) | |
2215 | { | |
2216 | unsigned long flags; | |
2217 | unsigned long x = 0; | |
2218 | struct page *page; | |
2219 | ||
2220 | spin_lock_irqsave(&n->list_lock, flags); | |
2221 | list_for_each_entry(page, &n->partial, lru) | |
2222 | x += get_count(page); | |
2223 | spin_unlock_irqrestore(&n->list_lock, flags); | |
2224 | return x; | |
2225 | } | |
9a02d699 | 2226 | #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */ |
26c02cf0 | 2227 | |
781b2ba6 PE |
2228 | static noinline void |
2229 | slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) | |
2230 | { | |
9a02d699 DR |
2231 | #ifdef CONFIG_SLUB_DEBUG |
2232 | static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, | |
2233 | DEFAULT_RATELIMIT_BURST); | |
781b2ba6 | 2234 | int node; |
fa45dc25 | 2235 | struct kmem_cache_node *n; |
781b2ba6 | 2236 | |
9a02d699 DR |
2237 | if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) |
2238 | return; | |
2239 | ||
5b3810e5 VB |
2240 | pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", |
2241 | nid, gfpflags, &gfpflags); | |
f9f58285 FF |
2242 | pr_warn(" cache: %s, object size: %d, buffer size: %d, default order: %d, min order: %d\n", |
2243 | s->name, s->object_size, s->size, oo_order(s->oo), | |
2244 | oo_order(s->min)); | |
781b2ba6 | 2245 | |
3b0efdfa | 2246 | if (oo_order(s->min) > get_order(s->object_size)) |
f9f58285 FF |
2247 | pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", |
2248 | s->name); | |
fa5ec8a1 | 2249 | |
fa45dc25 | 2250 | for_each_kmem_cache_node(s, node, n) { |
781b2ba6 PE |
2251 | unsigned long nr_slabs; |
2252 | unsigned long nr_objs; | |
2253 | unsigned long nr_free; | |
2254 | ||
26c02cf0 AB |
2255 | nr_free = count_partial(n, count_free); |
2256 | nr_slabs = node_nr_slabs(n); | |
2257 | nr_objs = node_nr_objs(n); | |
781b2ba6 | 2258 | |
f9f58285 | 2259 | pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", |
781b2ba6 PE |
2260 | node, nr_slabs, nr_objs, nr_free); |
2261 | } | |
9a02d699 | 2262 | #endif |
781b2ba6 PE |
2263 | } |
2264 | ||
497b66f2 CL |
2265 | static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags, |
2266 | int node, struct kmem_cache_cpu **pc) | |
2267 | { | |
6faa6833 | 2268 | void *freelist; |
188fd063 CL |
2269 | struct kmem_cache_cpu *c = *pc; |
2270 | struct page *page; | |
497b66f2 | 2271 | |
188fd063 | 2272 | freelist = get_partial(s, flags, node, c); |
497b66f2 | 2273 | |
188fd063 CL |
2274 | if (freelist) |
2275 | return freelist; | |
2276 | ||
2277 | page = new_slab(s, flags, node); | |
497b66f2 | 2278 | if (page) { |
7c8e0181 | 2279 | c = raw_cpu_ptr(s->cpu_slab); |
497b66f2 CL |
2280 | if (c->page) |
2281 | flush_slab(s, c); | |
2282 | ||
2283 | /* | |
2284 | * No other reference to the page yet so we can | |
2285 | * muck around with it freely without cmpxchg | |
2286 | */ | |
6faa6833 | 2287 | freelist = page->freelist; |
497b66f2 CL |
2288 | page->freelist = NULL; |
2289 | ||
2290 | stat(s, ALLOC_SLAB); | |
497b66f2 CL |
2291 | c->page = page; |
2292 | *pc = c; | |
2293 | } else | |
6faa6833 | 2294 | freelist = NULL; |
497b66f2 | 2295 | |
6faa6833 | 2296 | return freelist; |
497b66f2 CL |
2297 | } |
2298 | ||
072bb0aa MG |
2299 | static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags) |
2300 | { | |
2301 | if (unlikely(PageSlabPfmemalloc(page))) | |
2302 | return gfp_pfmemalloc_allowed(gfpflags); | |
2303 | ||
2304 | return true; | |
2305 | } | |
2306 | ||
213eeb9f | 2307 | /* |
d0e0ac97 CG |
2308 | * Check the page->freelist of a page and either transfer the freelist to the |
2309 | * per cpu freelist or deactivate the page. | |
213eeb9f CL |
2310 | * |
2311 | * The page is still frozen if the return value is not NULL. | |
2312 | * | |
2313 | * If this function returns NULL then the page has been unfrozen. | |
d24ac77f JK |
2314 | * |
2315 | * This function must be called with interrupt disabled. | |
213eeb9f CL |
2316 | */ |
2317 | static inline void *get_freelist(struct kmem_cache *s, struct page *page) | |
2318 | { | |
2319 | struct page new; | |
2320 | unsigned long counters; | |
2321 | void *freelist; | |
2322 | ||
2323 | do { | |
2324 | freelist = page->freelist; | |
2325 | counters = page->counters; | |
6faa6833 | 2326 | |
213eeb9f | 2327 | new.counters = counters; |
a0132ac0 | 2328 | VM_BUG_ON(!new.frozen); |
213eeb9f CL |
2329 | |
2330 | new.inuse = page->objects; | |
2331 | new.frozen = freelist != NULL; | |
2332 | ||
d24ac77f | 2333 | } while (!__cmpxchg_double_slab(s, page, |
213eeb9f CL |
2334 | freelist, counters, |
2335 | NULL, new.counters, | |
2336 | "get_freelist")); | |
2337 | ||
2338 | return freelist; | |
2339 | } | |
2340 | ||
81819f0f | 2341 | /* |
894b8788 CL |
2342 | * Slow path. The lockless freelist is empty or we need to perform |
2343 | * debugging duties. | |
2344 | * | |
894b8788 CL |
2345 | * Processing is still very fast if new objects have been freed to the |
2346 | * regular freelist. In that case we simply take over the regular freelist | |
2347 | * as the lockless freelist and zap the regular freelist. | |
81819f0f | 2348 | * |
894b8788 CL |
2349 | * If that is not working then we fall back to the partial lists. We take the |
2350 | * first element of the freelist as the object to allocate now and move the | |
2351 | * rest of the freelist to the lockless freelist. | |
81819f0f | 2352 | * |
894b8788 | 2353 | * And if we were unable to get a new slab from the partial slab lists then |
6446faa2 CL |
2354 | * we need to allocate a new slab. This is the slowest path since it involves |
2355 | * a call to the page allocator and the setup of a new slab. | |
a380a3c7 CL |
2356 | * |
2357 | * Version of __slab_alloc to use when we know that interrupts are | |
2358 | * already disabled (which is the case for bulk allocation). | |
81819f0f | 2359 | */ |
a380a3c7 | 2360 | static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, |
ce71e27c | 2361 | unsigned long addr, struct kmem_cache_cpu *c) |
81819f0f | 2362 | { |
6faa6833 | 2363 | void *freelist; |
f6e7def7 | 2364 | struct page *page; |
81819f0f | 2365 | |
f6e7def7 CL |
2366 | page = c->page; |
2367 | if (!page) | |
81819f0f | 2368 | goto new_slab; |
49e22585 | 2369 | redo: |
6faa6833 | 2370 | |
57d437d2 | 2371 | if (unlikely(!node_match(page, node))) { |
a561ce00 JK |
2372 | int searchnode = node; |
2373 | ||
2374 | if (node != NUMA_NO_NODE && !node_present_pages(node)) | |
2375 | searchnode = node_to_mem_node(node); | |
2376 | ||
2377 | if (unlikely(!node_match(page, searchnode))) { | |
2378 | stat(s, ALLOC_NODE_MISMATCH); | |
2379 | deactivate_slab(s, page, c->freelist); | |
2380 | c->page = NULL; | |
2381 | c->freelist = NULL; | |
2382 | goto new_slab; | |
2383 | } | |
fc59c053 | 2384 | } |
6446faa2 | 2385 | |
072bb0aa MG |
2386 | /* |
2387 | * By rights, we should be searching for a slab page that was | |
2388 | * PFMEMALLOC but right now, we are losing the pfmemalloc | |
2389 | * information when the page leaves the per-cpu allocator | |
2390 | */ | |
2391 | if (unlikely(!pfmemalloc_match(page, gfpflags))) { | |
2392 | deactivate_slab(s, page, c->freelist); | |
2393 | c->page = NULL; | |
2394 | c->freelist = NULL; | |
2395 | goto new_slab; | |
2396 | } | |
2397 | ||
73736e03 | 2398 | /* must check again c->freelist in case of cpu migration or IRQ */ |
6faa6833 CL |
2399 | freelist = c->freelist; |
2400 | if (freelist) | |
73736e03 | 2401 | goto load_freelist; |
03e404af | 2402 | |
f6e7def7 | 2403 | freelist = get_freelist(s, page); |
6446faa2 | 2404 | |
6faa6833 | 2405 | if (!freelist) { |
03e404af CL |
2406 | c->page = NULL; |
2407 | stat(s, DEACTIVATE_BYPASS); | |
fc59c053 | 2408 | goto new_slab; |
03e404af | 2409 | } |
6446faa2 | 2410 | |
84e554e6 | 2411 | stat(s, ALLOC_REFILL); |
6446faa2 | 2412 | |
894b8788 | 2413 | load_freelist: |
507effea CL |
2414 | /* |
2415 | * freelist is pointing to the list of objects to be used. | |
2416 | * page is pointing to the page from which the objects are obtained. | |
2417 | * That page must be frozen for per cpu allocations to work. | |
2418 | */ | |
a0132ac0 | 2419 | VM_BUG_ON(!c->page->frozen); |
6faa6833 | 2420 | c->freelist = get_freepointer(s, freelist); |
8a5ec0ba | 2421 | c->tid = next_tid(c->tid); |
6faa6833 | 2422 | return freelist; |
81819f0f | 2423 | |
81819f0f | 2424 | new_slab: |
2cfb7455 | 2425 | |
49e22585 | 2426 | if (c->partial) { |
f6e7def7 CL |
2427 | page = c->page = c->partial; |
2428 | c->partial = page->next; | |
49e22585 CL |
2429 | stat(s, CPU_PARTIAL_ALLOC); |
2430 | c->freelist = NULL; | |
2431 | goto redo; | |
81819f0f CL |
2432 | } |
2433 | ||
188fd063 | 2434 | freelist = new_slab_objects(s, gfpflags, node, &c); |
01ad8a7b | 2435 | |
f4697436 | 2436 | if (unlikely(!freelist)) { |
9a02d699 | 2437 | slab_out_of_memory(s, gfpflags, node); |
f4697436 | 2438 | return NULL; |
81819f0f | 2439 | } |
2cfb7455 | 2440 | |
f6e7def7 | 2441 | page = c->page; |
5091b74a | 2442 | if (likely(!kmem_cache_debug(s) && pfmemalloc_match(page, gfpflags))) |
4b6f0750 | 2443 | goto load_freelist; |
2cfb7455 | 2444 | |
497b66f2 | 2445 | /* Only entered in the debug case */ |
d0e0ac97 CG |
2446 | if (kmem_cache_debug(s) && |
2447 | !alloc_debug_processing(s, page, freelist, addr)) | |
497b66f2 | 2448 | goto new_slab; /* Slab failed checks. Next slab needed */ |
894b8788 | 2449 | |
f6e7def7 | 2450 | deactivate_slab(s, page, get_freepointer(s, freelist)); |
c17dda40 CL |
2451 | c->page = NULL; |
2452 | c->freelist = NULL; | |
6faa6833 | 2453 | return freelist; |
894b8788 CL |
2454 | } |
2455 | ||
a380a3c7 CL |
2456 | /* |
2457 | * Another one that disabled interrupt and compensates for possible | |
2458 | * cpu changes by refetching the per cpu area pointer. | |
2459 | */ | |
2460 | static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, | |
2461 | unsigned long addr, struct kmem_cache_cpu *c) | |
2462 | { | |
2463 | void *p; | |
2464 | unsigned long flags; | |
2465 | ||
2466 | local_irq_save(flags); | |
2467 | #ifdef CONFIG_PREEMPT | |
2468 | /* | |
2469 | * We may have been preempted and rescheduled on a different | |
2470 | * cpu before disabling interrupts. Need to reload cpu area | |
2471 | * pointer. | |
2472 | */ | |
2473 | c = this_cpu_ptr(s->cpu_slab); | |
2474 | #endif | |
2475 | ||
2476 | p = ___slab_alloc(s, gfpflags, node, addr, c); | |
2477 | local_irq_restore(flags); | |
2478 | return p; | |
2479 | } | |
2480 | ||
894b8788 CL |
2481 | /* |
2482 | * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) | |
2483 | * have the fastpath folded into their functions. So no function call | |
2484 | * overhead for requests that can be satisfied on the fastpath. | |
2485 | * | |
2486 | * The fastpath works by first checking if the lockless freelist can be used. | |
2487 | * If not then __slab_alloc is called for slow processing. | |
2488 | * | |
2489 | * Otherwise we can simply pick the next object from the lockless free list. | |
2490 | */ | |
2b847c3c | 2491 | static __always_inline void *slab_alloc_node(struct kmem_cache *s, |
ce71e27c | 2492 | gfp_t gfpflags, int node, unsigned long addr) |
894b8788 | 2493 | { |
03ec0ed5 | 2494 | void *object; |
dfb4f096 | 2495 | struct kmem_cache_cpu *c; |
57d437d2 | 2496 | struct page *page; |
8a5ec0ba | 2497 | unsigned long tid; |
1f84260c | 2498 | |
8135be5a VD |
2499 | s = slab_pre_alloc_hook(s, gfpflags); |
2500 | if (!s) | |
773ff60e | 2501 | return NULL; |
8a5ec0ba | 2502 | redo: |
8a5ec0ba CL |
2503 | /* |
2504 | * Must read kmem_cache cpu data via this cpu ptr. Preemption is | |
2505 | * enabled. We may switch back and forth between cpus while | |
2506 | * reading from one cpu area. That does not matter as long | |
2507 | * as we end up on the original cpu again when doing the cmpxchg. | |
7cccd80b | 2508 | * |
9aabf810 JK |
2509 | * We should guarantee that tid and kmem_cache are retrieved on |
2510 | * the same cpu. It could be different if CONFIG_PREEMPT so we need | |
2511 | * to check if it is matched or not. | |
8a5ec0ba | 2512 | */ |
9aabf810 JK |
2513 | do { |
2514 | tid = this_cpu_read(s->cpu_slab->tid); | |
2515 | c = raw_cpu_ptr(s->cpu_slab); | |
859b7a0e MR |
2516 | } while (IS_ENABLED(CONFIG_PREEMPT) && |
2517 | unlikely(tid != READ_ONCE(c->tid))); | |
9aabf810 JK |
2518 | |
2519 | /* | |
2520 | * Irqless object alloc/free algorithm used here depends on sequence | |
2521 | * of fetching cpu_slab's data. tid should be fetched before anything | |
2522 | * on c to guarantee that object and page associated with previous tid | |
2523 | * won't be used with current tid. If we fetch tid first, object and | |
2524 | * page could be one associated with next tid and our alloc/free | |
2525 | * request will be failed. In this case, we will retry. So, no problem. | |
2526 | */ | |
2527 | barrier(); | |
8a5ec0ba | 2528 | |
8a5ec0ba CL |
2529 | /* |
2530 | * The transaction ids are globally unique per cpu and per operation on | |
2531 | * a per cpu queue. Thus they can be guarantee that the cmpxchg_double | |
2532 | * occurs on the right processor and that there was no operation on the | |
2533 | * linked list in between. | |
2534 | */ | |
8a5ec0ba | 2535 | |
9dfc6e68 | 2536 | object = c->freelist; |
57d437d2 | 2537 | page = c->page; |
8eae1492 | 2538 | if (unlikely(!object || !node_match(page, node))) { |
dfb4f096 | 2539 | object = __slab_alloc(s, gfpflags, node, addr, c); |
8eae1492 DH |
2540 | stat(s, ALLOC_SLOWPATH); |
2541 | } else { | |
0ad9500e ED |
2542 | void *next_object = get_freepointer_safe(s, object); |
2543 | ||
8a5ec0ba | 2544 | /* |
25985edc | 2545 | * The cmpxchg will only match if there was no additional |
8a5ec0ba CL |
2546 | * operation and if we are on the right processor. |
2547 | * | |
d0e0ac97 CG |
2548 | * The cmpxchg does the following atomically (without lock |
2549 | * semantics!) | |
8a5ec0ba CL |
2550 | * 1. Relocate first pointer to the current per cpu area. |
2551 | * 2. Verify that tid and freelist have not been changed | |
2552 | * 3. If they were not changed replace tid and freelist | |
2553 | * | |
d0e0ac97 CG |
2554 | * Since this is without lock semantics the protection is only |
2555 | * against code executing on this cpu *not* from access by | |
2556 | * other cpus. | |
8a5ec0ba | 2557 | */ |
933393f5 | 2558 | if (unlikely(!this_cpu_cmpxchg_double( |
8a5ec0ba CL |
2559 | s->cpu_slab->freelist, s->cpu_slab->tid, |
2560 | object, tid, | |
0ad9500e | 2561 | next_object, next_tid(tid)))) { |
8a5ec0ba CL |
2562 | |
2563 | note_cmpxchg_failure("slab_alloc", s, tid); | |
2564 | goto redo; | |
2565 | } | |
0ad9500e | 2566 | prefetch_freepointer(s, next_object); |
84e554e6 | 2567 | stat(s, ALLOC_FASTPATH); |
894b8788 | 2568 | } |
8a5ec0ba | 2569 | |
74e2134f | 2570 | if (unlikely(gfpflags & __GFP_ZERO) && object) |
3b0efdfa | 2571 | memset(object, 0, s->object_size); |
d07dbea4 | 2572 | |
03ec0ed5 | 2573 | slab_post_alloc_hook(s, gfpflags, 1, &object); |
5a896d9e | 2574 | |
894b8788 | 2575 | return object; |
81819f0f CL |
2576 | } |
2577 | ||
2b847c3c EG |
2578 | static __always_inline void *slab_alloc(struct kmem_cache *s, |
2579 | gfp_t gfpflags, unsigned long addr) | |
2580 | { | |
2581 | return slab_alloc_node(s, gfpflags, NUMA_NO_NODE, addr); | |
2582 | } | |
2583 | ||
81819f0f CL |
2584 | void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) |
2585 | { | |
2b847c3c | 2586 | void *ret = slab_alloc(s, gfpflags, _RET_IP_); |
5b882be4 | 2587 | |
d0e0ac97 CG |
2588 | trace_kmem_cache_alloc(_RET_IP_, ret, s->object_size, |
2589 | s->size, gfpflags); | |
5b882be4 EGM |
2590 | |
2591 | return ret; | |
81819f0f CL |
2592 | } |
2593 | EXPORT_SYMBOL(kmem_cache_alloc); | |
2594 | ||
0f24f128 | 2595 | #ifdef CONFIG_TRACING |
4a92379b RK |
2596 | void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) |
2597 | { | |
2b847c3c | 2598 | void *ret = slab_alloc(s, gfpflags, _RET_IP_); |
4a92379b | 2599 | trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags); |
0316bec2 | 2600 | kasan_kmalloc(s, ret, size); |
4a92379b RK |
2601 | return ret; |
2602 | } | |
2603 | EXPORT_SYMBOL(kmem_cache_alloc_trace); | |
5b882be4 EGM |
2604 | #endif |
2605 | ||
81819f0f CL |
2606 | #ifdef CONFIG_NUMA |
2607 | void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) | |
2608 | { | |
2b847c3c | 2609 | void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_); |
5b882be4 | 2610 | |
ca2b84cb | 2611 | trace_kmem_cache_alloc_node(_RET_IP_, ret, |
3b0efdfa | 2612 | s->object_size, s->size, gfpflags, node); |
5b882be4 EGM |
2613 | |
2614 | return ret; | |
81819f0f CL |
2615 | } |
2616 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
81819f0f | 2617 | |
0f24f128 | 2618 | #ifdef CONFIG_TRACING |
4a92379b | 2619 | void *kmem_cache_alloc_node_trace(struct kmem_cache *s, |
5b882be4 | 2620 | gfp_t gfpflags, |
4a92379b | 2621 | int node, size_t size) |
5b882be4 | 2622 | { |
2b847c3c | 2623 | void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_); |
4a92379b RK |
2624 | |
2625 | trace_kmalloc_node(_RET_IP_, ret, | |
2626 | size, s->size, gfpflags, node); | |
0316bec2 AR |
2627 | |
2628 | kasan_kmalloc(s, ret, size); | |
4a92379b | 2629 | return ret; |
5b882be4 | 2630 | } |
4a92379b | 2631 | EXPORT_SYMBOL(kmem_cache_alloc_node_trace); |
5b882be4 | 2632 | #endif |
5d1f57e4 | 2633 | #endif |
5b882be4 | 2634 | |
81819f0f | 2635 | /* |
94e4d712 | 2636 | * Slow path handling. This may still be called frequently since objects |
894b8788 | 2637 | * have a longer lifetime than the cpu slabs in most processing loads. |
81819f0f | 2638 | * |
894b8788 CL |
2639 | * So we still attempt to reduce cache line usage. Just take the slab |
2640 | * lock and free the item. If there is no additional partial page | |
2641 | * handling required then we can return immediately. | |
81819f0f | 2642 | */ |
894b8788 | 2643 | static void __slab_free(struct kmem_cache *s, struct page *page, |
81084651 JDB |
2644 | void *head, void *tail, int cnt, |
2645 | unsigned long addr) | |
2646 | ||
81819f0f CL |
2647 | { |
2648 | void *prior; | |
2cfb7455 | 2649 | int was_frozen; |
2cfb7455 CL |
2650 | struct page new; |
2651 | unsigned long counters; | |
2652 | struct kmem_cache_node *n = NULL; | |
61728d1e | 2653 | unsigned long uninitialized_var(flags); |
81819f0f | 2654 | |
8a5ec0ba | 2655 | stat(s, FREE_SLOWPATH); |
81819f0f | 2656 | |
19c7ff9e | 2657 | if (kmem_cache_debug(s) && |
282acb43 | 2658 | !free_debug_processing(s, page, head, tail, cnt, addr)) |
80f08c19 | 2659 | return; |
6446faa2 | 2660 | |
2cfb7455 | 2661 | do { |
837d678d JK |
2662 | if (unlikely(n)) { |
2663 | spin_unlock_irqrestore(&n->list_lock, flags); | |
2664 | n = NULL; | |
2665 | } | |
2cfb7455 CL |
2666 | prior = page->freelist; |
2667 | counters = page->counters; | |
81084651 | 2668 | set_freepointer(s, tail, prior); |
2cfb7455 CL |
2669 | new.counters = counters; |
2670 | was_frozen = new.frozen; | |
81084651 | 2671 | new.inuse -= cnt; |
837d678d | 2672 | if ((!new.inuse || !prior) && !was_frozen) { |
49e22585 | 2673 | |
c65c1877 | 2674 | if (kmem_cache_has_cpu_partial(s) && !prior) { |
49e22585 CL |
2675 | |
2676 | /* | |
d0e0ac97 CG |
2677 | * Slab was on no list before and will be |
2678 | * partially empty | |
2679 | * We can defer the list move and instead | |
2680 | * freeze it. | |
49e22585 CL |
2681 | */ |
2682 | new.frozen = 1; | |
2683 | ||
c65c1877 | 2684 | } else { /* Needs to be taken off a list */ |
49e22585 | 2685 | |
b455def2 | 2686 | n = get_node(s, page_to_nid(page)); |
49e22585 CL |
2687 | /* |
2688 | * Speculatively acquire the list_lock. | |
2689 | * If the cmpxchg does not succeed then we may | |
2690 | * drop the list_lock without any processing. | |
2691 | * | |
2692 | * Otherwise the list_lock will synchronize with | |
2693 | * other processors updating the list of slabs. | |
2694 | */ | |
2695 | spin_lock_irqsave(&n->list_lock, flags); | |
2696 | ||
2697 | } | |
2cfb7455 | 2698 | } |
81819f0f | 2699 | |
2cfb7455 CL |
2700 | } while (!cmpxchg_double_slab(s, page, |
2701 | prior, counters, | |
81084651 | 2702 | head, new.counters, |
2cfb7455 | 2703 | "__slab_free")); |
81819f0f | 2704 | |
2cfb7455 | 2705 | if (likely(!n)) { |
49e22585 CL |
2706 | |
2707 | /* | |
2708 | * If we just froze the page then put it onto the | |
2709 | * per cpu partial list. | |
2710 | */ | |
8028dcea | 2711 | if (new.frozen && !was_frozen) { |
49e22585 | 2712 | put_cpu_partial(s, page, 1); |
8028dcea AS |
2713 | stat(s, CPU_PARTIAL_FREE); |
2714 | } | |
49e22585 | 2715 | /* |
2cfb7455 CL |
2716 | * The list lock was not taken therefore no list |
2717 | * activity can be necessary. | |
2718 | */ | |
b455def2 L |
2719 | if (was_frozen) |
2720 | stat(s, FREE_FROZEN); | |
2721 | return; | |
2722 | } | |
81819f0f | 2723 | |
8a5b20ae | 2724 | if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) |
837d678d JK |
2725 | goto slab_empty; |
2726 | ||
81819f0f | 2727 | /* |
837d678d JK |
2728 | * Objects left in the slab. If it was not on the partial list before |
2729 | * then add it. | |
81819f0f | 2730 | */ |
345c905d JK |
2731 | if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { |
2732 | if (kmem_cache_debug(s)) | |
c65c1877 | 2733 | remove_full(s, n, page); |
837d678d JK |
2734 | add_partial(n, page, DEACTIVATE_TO_TAIL); |
2735 | stat(s, FREE_ADD_PARTIAL); | |
8ff12cfc | 2736 | } |
80f08c19 | 2737 | spin_unlock_irqrestore(&n->list_lock, flags); |
81819f0f CL |
2738 | return; |
2739 | ||
2740 | slab_empty: | |
a973e9dd | 2741 | if (prior) { |
81819f0f | 2742 | /* |
6fbabb20 | 2743 | * Slab on the partial list. |
81819f0f | 2744 | */ |
5cc6eee8 | 2745 | remove_partial(n, page); |
84e554e6 | 2746 | stat(s, FREE_REMOVE_PARTIAL); |
c65c1877 | 2747 | } else { |
6fbabb20 | 2748 | /* Slab must be on the full list */ |
c65c1877 PZ |
2749 | remove_full(s, n, page); |
2750 | } | |
2cfb7455 | 2751 | |
80f08c19 | 2752 | spin_unlock_irqrestore(&n->list_lock, flags); |
84e554e6 | 2753 | stat(s, FREE_SLAB); |
81819f0f | 2754 | discard_slab(s, page); |
81819f0f CL |
2755 | } |
2756 | ||
894b8788 CL |
2757 | /* |
2758 | * Fastpath with forced inlining to produce a kfree and kmem_cache_free that | |
2759 | * can perform fastpath freeing without additional function calls. | |
2760 | * | |
2761 | * The fastpath is only possible if we are freeing to the current cpu slab | |
2762 | * of this processor. This typically the case if we have just allocated | |
2763 | * the item before. | |
2764 | * | |
2765 | * If fastpath is not possible then fall back to __slab_free where we deal | |
2766 | * with all sorts of special processing. | |
81084651 JDB |
2767 | * |
2768 | * Bulk free of a freelist with several objects (all pointing to the | |
2769 | * same page) possible by specifying head and tail ptr, plus objects | |
2770 | * count (cnt). Bulk free indicated by tail pointer being set. | |
894b8788 | 2771 | */ |
81084651 JDB |
2772 | static __always_inline void slab_free(struct kmem_cache *s, struct page *page, |
2773 | void *head, void *tail, int cnt, | |
2774 | unsigned long addr) | |
894b8788 | 2775 | { |
81084651 | 2776 | void *tail_obj = tail ? : head; |
dfb4f096 | 2777 | struct kmem_cache_cpu *c; |
8a5ec0ba | 2778 | unsigned long tid; |
1f84260c | 2779 | |
81084651 | 2780 | slab_free_freelist_hook(s, head, tail); |
c016b0bd | 2781 | |
8a5ec0ba CL |
2782 | redo: |
2783 | /* | |
2784 | * Determine the currently cpus per cpu slab. | |
2785 | * The cpu may change afterward. However that does not matter since | |
2786 | * data is retrieved via this pointer. If we are on the same cpu | |
2ae44005 | 2787 | * during the cmpxchg then the free will succeed. |
8a5ec0ba | 2788 | */ |
9aabf810 JK |
2789 | do { |
2790 | tid = this_cpu_read(s->cpu_slab->tid); | |
2791 | c = raw_cpu_ptr(s->cpu_slab); | |
859b7a0e MR |
2792 | } while (IS_ENABLED(CONFIG_PREEMPT) && |
2793 | unlikely(tid != READ_ONCE(c->tid))); | |
c016b0bd | 2794 | |
9aabf810 JK |
2795 | /* Same with comment on barrier() in slab_alloc_node() */ |
2796 | barrier(); | |
c016b0bd | 2797 | |
442b06bc | 2798 | if (likely(page == c->page)) { |
81084651 | 2799 | set_freepointer(s, tail_obj, c->freelist); |
8a5ec0ba | 2800 | |
933393f5 | 2801 | if (unlikely(!this_cpu_cmpxchg_double( |
8a5ec0ba CL |
2802 | s->cpu_slab->freelist, s->cpu_slab->tid, |
2803 | c->freelist, tid, | |
81084651 | 2804 | head, next_tid(tid)))) { |
8a5ec0ba CL |
2805 | |
2806 | note_cmpxchg_failure("slab_free", s, tid); | |
2807 | goto redo; | |
2808 | } | |
84e554e6 | 2809 | stat(s, FREE_FASTPATH); |
894b8788 | 2810 | } else |
81084651 | 2811 | __slab_free(s, page, head, tail_obj, cnt, addr); |
894b8788 | 2812 | |
894b8788 CL |
2813 | } |
2814 | ||
81819f0f CL |
2815 | void kmem_cache_free(struct kmem_cache *s, void *x) |
2816 | { | |
b9ce5ef4 GC |
2817 | s = cache_from_obj(s, x); |
2818 | if (!s) | |
79576102 | 2819 | return; |
81084651 | 2820 | slab_free(s, virt_to_head_page(x), x, NULL, 1, _RET_IP_); |
ca2b84cb | 2821 | trace_kmem_cache_free(_RET_IP_, x); |
81819f0f CL |
2822 | } |
2823 | EXPORT_SYMBOL(kmem_cache_free); | |
2824 | ||
d0ecd894 | 2825 | struct detached_freelist { |
fbd02630 | 2826 | struct page *page; |
d0ecd894 JDB |
2827 | void *tail; |
2828 | void *freelist; | |
2829 | int cnt; | |
376bf125 | 2830 | struct kmem_cache *s; |
d0ecd894 | 2831 | }; |
fbd02630 | 2832 | |
d0ecd894 JDB |
2833 | /* |
2834 | * This function progressively scans the array with free objects (with | |
2835 | * a limited look ahead) and extract objects belonging to the same | |
2836 | * page. It builds a detached freelist directly within the given | |
2837 | * page/objects. This can happen without any need for | |
2838 | * synchronization, because the objects are owned by running process. | |
2839 | * The freelist is build up as a single linked list in the objects. | |
2840 | * The idea is, that this detached freelist can then be bulk | |
2841 | * transferred to the real freelist(s), but only requiring a single | |
2842 | * synchronization primitive. Look ahead in the array is limited due | |
2843 | * to performance reasons. | |
2844 | */ | |
376bf125 JDB |
2845 | static inline |
2846 | int build_detached_freelist(struct kmem_cache *s, size_t size, | |
2847 | void **p, struct detached_freelist *df) | |
d0ecd894 JDB |
2848 | { |
2849 | size_t first_skipped_index = 0; | |
2850 | int lookahead = 3; | |
2851 | void *object; | |
ca257195 | 2852 | struct page *page; |
fbd02630 | 2853 | |
d0ecd894 JDB |
2854 | /* Always re-init detached_freelist */ |
2855 | df->page = NULL; | |
fbd02630 | 2856 | |
d0ecd894 JDB |
2857 | do { |
2858 | object = p[--size]; | |
ca257195 | 2859 | /* Do we need !ZERO_OR_NULL_PTR(object) here? (for kfree) */ |
d0ecd894 | 2860 | } while (!object && size); |
3eed034d | 2861 | |
d0ecd894 JDB |
2862 | if (!object) |
2863 | return 0; | |
fbd02630 | 2864 | |
ca257195 JDB |
2865 | page = virt_to_head_page(object); |
2866 | if (!s) { | |
2867 | /* Handle kalloc'ed objects */ | |
2868 | if (unlikely(!PageSlab(page))) { | |
2869 | BUG_ON(!PageCompound(page)); | |
2870 | kfree_hook(object); | |
2871 | __free_kmem_pages(page, compound_order(page)); | |
2872 | p[size] = NULL; /* mark object processed */ | |
2873 | return size; | |
2874 | } | |
2875 | /* Derive kmem_cache from object */ | |
2876 | df->s = page->slab_cache; | |
2877 | } else { | |
2878 | df->s = cache_from_obj(s, object); /* Support for memcg */ | |
2879 | } | |
376bf125 | 2880 | |
d0ecd894 | 2881 | /* Start new detached freelist */ |
ca257195 | 2882 | df->page = page; |
376bf125 | 2883 | set_freepointer(df->s, object, NULL); |
d0ecd894 JDB |
2884 | df->tail = object; |
2885 | df->freelist = object; | |
2886 | p[size] = NULL; /* mark object processed */ | |
2887 | df->cnt = 1; | |
2888 | ||
2889 | while (size) { | |
2890 | object = p[--size]; | |
2891 | if (!object) | |
2892 | continue; /* Skip processed objects */ | |
2893 | ||
2894 | /* df->page is always set at this point */ | |
2895 | if (df->page == virt_to_head_page(object)) { | |
2896 | /* Opportunity build freelist */ | |
376bf125 | 2897 | set_freepointer(df->s, object, df->freelist); |
d0ecd894 JDB |
2898 | df->freelist = object; |
2899 | df->cnt++; | |
2900 | p[size] = NULL; /* mark object processed */ | |
2901 | ||
2902 | continue; | |
fbd02630 | 2903 | } |
d0ecd894 JDB |
2904 | |
2905 | /* Limit look ahead search */ | |
2906 | if (!--lookahead) | |
2907 | break; | |
2908 | ||
2909 | if (!first_skipped_index) | |
2910 | first_skipped_index = size + 1; | |
fbd02630 | 2911 | } |
d0ecd894 JDB |
2912 | |
2913 | return first_skipped_index; | |
2914 | } | |
2915 | ||
d0ecd894 | 2916 | /* Note that interrupts must be enabled when calling this function. */ |
376bf125 | 2917 | void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) |
d0ecd894 JDB |
2918 | { |
2919 | if (WARN_ON(!size)) | |
2920 | return; | |
2921 | ||
2922 | do { | |
2923 | struct detached_freelist df; | |
2924 | ||
2925 | size = build_detached_freelist(s, size, p, &df); | |
2926 | if (unlikely(!df.page)) | |
2927 | continue; | |
2928 | ||
376bf125 | 2929 | slab_free(df.s, df.page, df.freelist, df.tail, df.cnt,_RET_IP_); |
d0ecd894 | 2930 | } while (likely(size)); |
484748f0 CL |
2931 | } |
2932 | EXPORT_SYMBOL(kmem_cache_free_bulk); | |
2933 | ||
994eb764 | 2934 | /* Note that interrupts must be enabled when calling this function. */ |
865762a8 JDB |
2935 | int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, |
2936 | void **p) | |
484748f0 | 2937 | { |
994eb764 JDB |
2938 | struct kmem_cache_cpu *c; |
2939 | int i; | |
2940 | ||
03ec0ed5 JDB |
2941 | /* memcg and kmem_cache debug support */ |
2942 | s = slab_pre_alloc_hook(s, flags); | |
2943 | if (unlikely(!s)) | |
2944 | return false; | |
994eb764 JDB |
2945 | /* |
2946 | * Drain objects in the per cpu slab, while disabling local | |
2947 | * IRQs, which protects against PREEMPT and interrupts | |
2948 | * handlers invoking normal fastpath. | |
2949 | */ | |
2950 | local_irq_disable(); | |
2951 | c = this_cpu_ptr(s->cpu_slab); | |
2952 | ||
2953 | for (i = 0; i < size; i++) { | |
2954 | void *object = c->freelist; | |
2955 | ||
ebe909e0 | 2956 | if (unlikely(!object)) { |
ebe909e0 JDB |
2957 | /* |
2958 | * Invoking slow path likely have side-effect | |
2959 | * of re-populating per CPU c->freelist | |
2960 | */ | |
87098373 | 2961 | p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, |
ebe909e0 | 2962 | _RET_IP_, c); |
87098373 CL |
2963 | if (unlikely(!p[i])) |
2964 | goto error; | |
2965 | ||
ebe909e0 JDB |
2966 | c = this_cpu_ptr(s->cpu_slab); |
2967 | continue; /* goto for-loop */ | |
2968 | } | |
994eb764 JDB |
2969 | c->freelist = get_freepointer(s, object); |
2970 | p[i] = object; | |
2971 | } | |
2972 | c->tid = next_tid(c->tid); | |
2973 | local_irq_enable(); | |
2974 | ||
2975 | /* Clear memory outside IRQ disabled fastpath loop */ | |
2976 | if (unlikely(flags & __GFP_ZERO)) { | |
2977 | int j; | |
2978 | ||
2979 | for (j = 0; j < i; j++) | |
2980 | memset(p[j], 0, s->object_size); | |
2981 | } | |
2982 | ||
03ec0ed5 JDB |
2983 | /* memcg and kmem_cache debug support */ |
2984 | slab_post_alloc_hook(s, flags, size, p); | |
865762a8 | 2985 | return i; |
87098373 | 2986 | error: |
87098373 | 2987 | local_irq_enable(); |
03ec0ed5 JDB |
2988 | slab_post_alloc_hook(s, flags, i, p); |
2989 | __kmem_cache_free_bulk(s, i, p); | |
865762a8 | 2990 | return 0; |
484748f0 CL |
2991 | } |
2992 | EXPORT_SYMBOL(kmem_cache_alloc_bulk); | |
2993 | ||
2994 | ||
81819f0f | 2995 | /* |
672bba3a CL |
2996 | * Object placement in a slab is made very easy because we always start at |
2997 | * offset 0. If we tune the size of the object to the alignment then we can | |
2998 | * get the required alignment by putting one properly sized object after | |
2999 | * another. | |
81819f0f CL |
3000 | * |
3001 | * Notice that the allocation order determines the sizes of the per cpu | |
3002 | * caches. Each processor has always one slab available for allocations. | |
3003 | * Increasing the allocation order reduces the number of times that slabs | |
672bba3a | 3004 | * must be moved on and off the partial lists and is therefore a factor in |
81819f0f | 3005 | * locking overhead. |
81819f0f CL |
3006 | */ |
3007 | ||
3008 | /* | |
3009 | * Mininum / Maximum order of slab pages. This influences locking overhead | |
3010 | * and slab fragmentation. A higher order reduces the number of partial slabs | |
3011 | * and increases the number of allocations possible without having to | |
3012 | * take the list_lock. | |
3013 | */ | |
3014 | static int slub_min_order; | |
114e9e89 | 3015 | static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER; |
9b2cd506 | 3016 | static int slub_min_objects; |
81819f0f | 3017 | |
81819f0f CL |
3018 | /* |
3019 | * Calculate the order of allocation given an slab object size. | |
3020 | * | |
672bba3a CL |
3021 | * The order of allocation has significant impact on performance and other |
3022 | * system components. Generally order 0 allocations should be preferred since | |
3023 | * order 0 does not cause fragmentation in the page allocator. Larger objects | |
3024 | * be problematic to put into order 0 slabs because there may be too much | |
c124f5b5 | 3025 | * unused space left. We go to a higher order if more than 1/16th of the slab |
672bba3a CL |
3026 | * would be wasted. |
3027 | * | |
3028 | * In order to reach satisfactory performance we must ensure that a minimum | |
3029 | * number of objects is in one slab. Otherwise we may generate too much | |
3030 | * activity on the partial lists which requires taking the list_lock. This is | |
3031 | * less a concern for large slabs though which are rarely used. | |
81819f0f | 3032 | * |
672bba3a CL |
3033 | * slub_max_order specifies the order where we begin to stop considering the |
3034 | * number of objects in a slab as critical. If we reach slub_max_order then | |
3035 | * we try to keep the page order as low as possible. So we accept more waste | |
3036 | * of space in favor of a small page order. | |
81819f0f | 3037 | * |
672bba3a CL |
3038 | * Higher order allocations also allow the placement of more objects in a |
3039 | * slab and thereby reduce object handling overhead. If the user has | |
3040 | * requested a higher mininum order then we start with that one instead of | |
3041 | * the smallest order which will fit the object. | |
81819f0f | 3042 | */ |
5e6d444e | 3043 | static inline int slab_order(int size, int min_objects, |
ab9a0f19 | 3044 | int max_order, int fract_leftover, int reserved) |
81819f0f CL |
3045 | { |
3046 | int order; | |
3047 | int rem; | |
6300ea75 | 3048 | int min_order = slub_min_order; |
81819f0f | 3049 | |
ab9a0f19 | 3050 | if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE) |
210b5c06 | 3051 | return get_order(size * MAX_OBJS_PER_PAGE) - 1; |
39b26464 | 3052 | |
9f835703 | 3053 | for (order = max(min_order, get_order(min_objects * size + reserved)); |
5e6d444e | 3054 | order <= max_order; order++) { |
81819f0f | 3055 | |
5e6d444e | 3056 | unsigned long slab_size = PAGE_SIZE << order; |
81819f0f | 3057 | |
ab9a0f19 | 3058 | rem = (slab_size - reserved) % size; |
81819f0f | 3059 | |
5e6d444e | 3060 | if (rem <= slab_size / fract_leftover) |
81819f0f | 3061 | break; |
81819f0f | 3062 | } |
672bba3a | 3063 | |
81819f0f CL |
3064 | return order; |
3065 | } | |
3066 | ||
ab9a0f19 | 3067 | static inline int calculate_order(int size, int reserved) |
5e6d444e CL |
3068 | { |
3069 | int order; | |
3070 | int min_objects; | |
3071 | int fraction; | |
e8120ff1 | 3072 | int max_objects; |
5e6d444e CL |
3073 | |
3074 | /* | |
3075 | * Attempt to find best configuration for a slab. This | |
3076 | * works by first attempting to generate a layout with | |
3077 | * the best configuration and backing off gradually. | |
3078 | * | |
422ff4d7 | 3079 | * First we increase the acceptable waste in a slab. Then |
5e6d444e CL |
3080 | * we reduce the minimum objects required in a slab. |
3081 | */ | |
3082 | min_objects = slub_min_objects; | |
9b2cd506 CL |
3083 | if (!min_objects) |
3084 | min_objects = 4 * (fls(nr_cpu_ids) + 1); | |
ab9a0f19 | 3085 | max_objects = order_objects(slub_max_order, size, reserved); |
e8120ff1 ZY |
3086 | min_objects = min(min_objects, max_objects); |
3087 | ||
5e6d444e | 3088 | while (min_objects > 1) { |
c124f5b5 | 3089 | fraction = 16; |
5e6d444e CL |
3090 | while (fraction >= 4) { |
3091 | order = slab_order(size, min_objects, | |
ab9a0f19 | 3092 | slub_max_order, fraction, reserved); |
5e6d444e CL |
3093 | if (order <= slub_max_order) |
3094 | return order; | |
3095 | fraction /= 2; | |
3096 | } | |
5086c389 | 3097 | min_objects--; |
5e6d444e CL |
3098 | } |
3099 | ||
3100 | /* | |
3101 | * We were unable to place multiple objects in a slab. Now | |
3102 | * lets see if we can place a single object there. | |
3103 | */ | |
ab9a0f19 | 3104 | order = slab_order(size, 1, slub_max_order, 1, reserved); |
5e6d444e CL |
3105 | if (order <= slub_max_order) |
3106 | return order; | |
3107 | ||
3108 | /* | |
3109 | * Doh this slab cannot be placed using slub_max_order. | |
3110 | */ | |
ab9a0f19 | 3111 | order = slab_order(size, 1, MAX_ORDER, 1, reserved); |
818cf590 | 3112 | if (order < MAX_ORDER) |
5e6d444e CL |
3113 | return order; |
3114 | return -ENOSYS; | |
3115 | } | |
3116 | ||
5595cffc | 3117 | static void |
4053497d | 3118 | init_kmem_cache_node(struct kmem_cache_node *n) |
81819f0f CL |
3119 | { |
3120 | n->nr_partial = 0; | |
81819f0f CL |
3121 | spin_lock_init(&n->list_lock); |
3122 | INIT_LIST_HEAD(&n->partial); | |
8ab1372f | 3123 | #ifdef CONFIG_SLUB_DEBUG |
0f389ec6 | 3124 | atomic_long_set(&n->nr_slabs, 0); |
02b71b70 | 3125 | atomic_long_set(&n->total_objects, 0); |
643b1138 | 3126 | INIT_LIST_HEAD(&n->full); |
8ab1372f | 3127 | #endif |
81819f0f CL |
3128 | } |
3129 | ||
55136592 | 3130 | static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) |
4c93c355 | 3131 | { |
6c182dc0 | 3132 | BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < |
95a05b42 | 3133 | KMALLOC_SHIFT_HIGH * sizeof(struct kmem_cache_cpu)); |
4c93c355 | 3134 | |
8a5ec0ba | 3135 | /* |
d4d84fef CM |
3136 | * Must align to double word boundary for the double cmpxchg |
3137 | * instructions to work; see __pcpu_double_call_return_bool(). | |
8a5ec0ba | 3138 | */ |
d4d84fef CM |
3139 | s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), |
3140 | 2 * sizeof(void *)); | |
8a5ec0ba CL |
3141 | |
3142 | if (!s->cpu_slab) | |
3143 | return 0; | |
3144 | ||
3145 | init_kmem_cache_cpus(s); | |
4c93c355 | 3146 | |
8a5ec0ba | 3147 | return 1; |
4c93c355 | 3148 | } |
4c93c355 | 3149 | |
51df1142 CL |
3150 | static struct kmem_cache *kmem_cache_node; |
3151 | ||
81819f0f CL |
3152 | /* |
3153 | * No kmalloc_node yet so do it by hand. We know that this is the first | |
3154 | * slab on the node for this slabcache. There are no concurrent accesses | |
3155 | * possible. | |
3156 | * | |
721ae22a ZYW |
3157 | * Note that this function only works on the kmem_cache_node |
3158 | * when allocating for the kmem_cache_node. This is used for bootstrapping | |
4c93c355 | 3159 | * memory on a fresh node that has no slab structures yet. |
81819f0f | 3160 | */ |
55136592 | 3161 | static void early_kmem_cache_node_alloc(int node) |
81819f0f CL |
3162 | { |
3163 | struct page *page; | |
3164 | struct kmem_cache_node *n; | |
3165 | ||
51df1142 | 3166 | BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); |
81819f0f | 3167 | |
51df1142 | 3168 | page = new_slab(kmem_cache_node, GFP_NOWAIT, node); |
81819f0f CL |
3169 | |
3170 | BUG_ON(!page); | |
a2f92ee7 | 3171 | if (page_to_nid(page) != node) { |
f9f58285 FF |
3172 | pr_err("SLUB: Unable to allocate memory from node %d\n", node); |
3173 | pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); | |
a2f92ee7 CL |
3174 | } |
3175 | ||
81819f0f CL |
3176 | n = page->freelist; |
3177 | BUG_ON(!n); | |
51df1142 | 3178 | page->freelist = get_freepointer(kmem_cache_node, n); |
e6e82ea1 | 3179 | page->inuse = 1; |
8cb0a506 | 3180 | page->frozen = 0; |
51df1142 | 3181 | kmem_cache_node->node[node] = n; |
8ab1372f | 3182 | #ifdef CONFIG_SLUB_DEBUG |
f7cb1933 | 3183 | init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); |
51df1142 | 3184 | init_tracking(kmem_cache_node, n); |
8ab1372f | 3185 | #endif |
0316bec2 | 3186 | kasan_kmalloc(kmem_cache_node, n, sizeof(struct kmem_cache_node)); |
4053497d | 3187 | init_kmem_cache_node(n); |
51df1142 | 3188 | inc_slabs_node(kmem_cache_node, node, page->objects); |
6446faa2 | 3189 | |
67b6c900 | 3190 | /* |
1e4dd946 SR |
3191 | * No locks need to be taken here as it has just been |
3192 | * initialized and there is no concurrent access. | |
67b6c900 | 3193 | */ |
1e4dd946 | 3194 | __add_partial(n, page, DEACTIVATE_TO_HEAD); |
81819f0f CL |
3195 | } |
3196 | ||
3197 | static void free_kmem_cache_nodes(struct kmem_cache *s) | |
3198 | { | |
3199 | int node; | |
fa45dc25 | 3200 | struct kmem_cache_node *n; |
81819f0f | 3201 | |
fa45dc25 CL |
3202 | for_each_kmem_cache_node(s, node, n) { |
3203 | kmem_cache_free(kmem_cache_node, n); | |
81819f0f CL |
3204 | s->node[node] = NULL; |
3205 | } | |
3206 | } | |
3207 | ||
52b4b950 DS |
3208 | void __kmem_cache_release(struct kmem_cache *s) |
3209 | { | |
3210 | free_percpu(s->cpu_slab); | |
3211 | free_kmem_cache_nodes(s); | |
3212 | } | |
3213 | ||
55136592 | 3214 | static int init_kmem_cache_nodes(struct kmem_cache *s) |
81819f0f CL |
3215 | { |
3216 | int node; | |
81819f0f | 3217 | |
f64dc58c | 3218 | for_each_node_state(node, N_NORMAL_MEMORY) { |
81819f0f CL |
3219 | struct kmem_cache_node *n; |
3220 | ||
73367bd8 | 3221 | if (slab_state == DOWN) { |
55136592 | 3222 | early_kmem_cache_node_alloc(node); |
73367bd8 AD |
3223 | continue; |
3224 | } | |
51df1142 | 3225 | n = kmem_cache_alloc_node(kmem_cache_node, |
55136592 | 3226 | GFP_KERNEL, node); |
81819f0f | 3227 | |
73367bd8 AD |
3228 | if (!n) { |
3229 | free_kmem_cache_nodes(s); | |
3230 | return 0; | |
81819f0f | 3231 | } |
73367bd8 | 3232 | |
81819f0f | 3233 | s->node[node] = n; |
4053497d | 3234 | init_kmem_cache_node(n); |
81819f0f CL |
3235 | } |
3236 | return 1; | |
3237 | } | |
81819f0f | 3238 | |
c0bdb232 | 3239 | static void set_min_partial(struct kmem_cache *s, unsigned long min) |
3b89d7d8 DR |
3240 | { |
3241 | if (min < MIN_PARTIAL) | |
3242 | min = MIN_PARTIAL; | |
3243 | else if (min > MAX_PARTIAL) | |
3244 | min = MAX_PARTIAL; | |
3245 | s->min_partial = min; | |
3246 | } | |
3247 | ||
81819f0f CL |
3248 | /* |
3249 | * calculate_sizes() determines the order and the distribution of data within | |
3250 | * a slab object. | |
3251 | */ | |
06b285dc | 3252 | static int calculate_sizes(struct kmem_cache *s, int forced_order) |
81819f0f CL |
3253 | { |
3254 | unsigned long flags = s->flags; | |
3b0efdfa | 3255 | unsigned long size = s->object_size; |
834f3d11 | 3256 | int order; |
81819f0f | 3257 | |
d8b42bf5 CL |
3258 | /* |
3259 | * Round up object size to the next word boundary. We can only | |
3260 | * place the free pointer at word boundaries and this determines | |
3261 | * the possible location of the free pointer. | |
3262 | */ | |
3263 | size = ALIGN(size, sizeof(void *)); | |
3264 | ||
3265 | #ifdef CONFIG_SLUB_DEBUG | |
81819f0f CL |
3266 | /* |
3267 | * Determine if we can poison the object itself. If the user of | |
3268 | * the slab may touch the object after free or before allocation | |
3269 | * then we should never poison the object itself. | |
3270 | */ | |
3271 | if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) && | |
c59def9f | 3272 | !s->ctor) |
81819f0f CL |
3273 | s->flags |= __OBJECT_POISON; |
3274 | else | |
3275 | s->flags &= ~__OBJECT_POISON; | |
3276 | ||
81819f0f CL |
3277 | |
3278 | /* | |
672bba3a | 3279 | * If we are Redzoning then check if there is some space between the |
81819f0f | 3280 | * end of the object and the free pointer. If not then add an |
672bba3a | 3281 | * additional word to have some bytes to store Redzone information. |
81819f0f | 3282 | */ |
3b0efdfa | 3283 | if ((flags & SLAB_RED_ZONE) && size == s->object_size) |
81819f0f | 3284 | size += sizeof(void *); |
41ecc55b | 3285 | #endif |
81819f0f CL |
3286 | |
3287 | /* | |
672bba3a CL |
3288 | * With that we have determined the number of bytes in actual use |
3289 | * by the object. This is the potential offset to the free pointer. | |
81819f0f CL |
3290 | */ |
3291 | s->inuse = size; | |
3292 | ||
3293 | if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) || | |
c59def9f | 3294 | s->ctor)) { |
81819f0f CL |
3295 | /* |
3296 | * Relocate free pointer after the object if it is not | |
3297 | * permitted to overwrite the first word of the object on | |
3298 | * kmem_cache_free. | |
3299 | * | |
3300 | * This is the case if we do RCU, have a constructor or | |
3301 | * destructor or are poisoning the objects. | |
3302 | */ | |
3303 | s->offset = size; | |
3304 | size += sizeof(void *); | |
3305 | } | |
3306 | ||
c12b3c62 | 3307 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
3308 | if (flags & SLAB_STORE_USER) |
3309 | /* | |
3310 | * Need to store information about allocs and frees after | |
3311 | * the object. | |
3312 | */ | |
3313 | size += 2 * sizeof(struct track); | |
3314 | ||
d86bd1be | 3315 | if (flags & SLAB_RED_ZONE) { |
81819f0f CL |
3316 | /* |
3317 | * Add some empty padding so that we can catch | |
3318 | * overwrites from earlier objects rather than let | |
3319 | * tracking information or the free pointer be | |
0211a9c8 | 3320 | * corrupted if a user writes before the start |
81819f0f CL |
3321 | * of the object. |
3322 | */ | |
3323 | size += sizeof(void *); | |
d86bd1be JK |
3324 | |
3325 | s->red_left_pad = sizeof(void *); | |
3326 | s->red_left_pad = ALIGN(s->red_left_pad, s->align); | |
3327 | size += s->red_left_pad; | |
3328 | } | |
41ecc55b | 3329 | #endif |
672bba3a | 3330 | |
81819f0f CL |
3331 | /* |
3332 | * SLUB stores one object immediately after another beginning from | |
3333 | * offset 0. In order to align the objects we have to simply size | |
3334 | * each object to conform to the alignment. | |
3335 | */ | |
45906855 | 3336 | size = ALIGN(size, s->align); |
81819f0f | 3337 | s->size = size; |
06b285dc CL |
3338 | if (forced_order >= 0) |
3339 | order = forced_order; | |
3340 | else | |
ab9a0f19 | 3341 | order = calculate_order(size, s->reserved); |
81819f0f | 3342 | |
834f3d11 | 3343 | if (order < 0) |
81819f0f CL |
3344 | return 0; |
3345 | ||
b7a49f0d | 3346 | s->allocflags = 0; |
834f3d11 | 3347 | if (order) |
b7a49f0d CL |
3348 | s->allocflags |= __GFP_COMP; |
3349 | ||
3350 | if (s->flags & SLAB_CACHE_DMA) | |
2c59dd65 | 3351 | s->allocflags |= GFP_DMA; |
b7a49f0d CL |
3352 | |
3353 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
3354 | s->allocflags |= __GFP_RECLAIMABLE; | |
3355 | ||
81819f0f CL |
3356 | /* |
3357 | * Determine the number of objects per slab | |
3358 | */ | |
ab9a0f19 LJ |
3359 | s->oo = oo_make(order, size, s->reserved); |
3360 | s->min = oo_make(get_order(size), size, s->reserved); | |
205ab99d CL |
3361 | if (oo_objects(s->oo) > oo_objects(s->max)) |
3362 | s->max = s->oo; | |
81819f0f | 3363 | |
834f3d11 | 3364 | return !!oo_objects(s->oo); |
81819f0f CL |
3365 | } |
3366 | ||
8a13a4cc | 3367 | static int kmem_cache_open(struct kmem_cache *s, unsigned long flags) |
81819f0f | 3368 | { |
8a13a4cc | 3369 | s->flags = kmem_cache_flags(s->size, flags, s->name, s->ctor); |
ab9a0f19 | 3370 | s->reserved = 0; |
81819f0f | 3371 | |
da9a638c LJ |
3372 | if (need_reserve_slab_rcu && (s->flags & SLAB_DESTROY_BY_RCU)) |
3373 | s->reserved = sizeof(struct rcu_head); | |
81819f0f | 3374 | |
06b285dc | 3375 | if (!calculate_sizes(s, -1)) |
81819f0f | 3376 | goto error; |
3de47213 DR |
3377 | if (disable_higher_order_debug) { |
3378 | /* | |
3379 | * Disable debugging flags that store metadata if the min slab | |
3380 | * order increased. | |
3381 | */ | |
3b0efdfa | 3382 | if (get_order(s->size) > get_order(s->object_size)) { |
3de47213 DR |
3383 | s->flags &= ~DEBUG_METADATA_FLAGS; |
3384 | s->offset = 0; | |
3385 | if (!calculate_sizes(s, -1)) | |
3386 | goto error; | |
3387 | } | |
3388 | } | |
81819f0f | 3389 | |
2565409f HC |
3390 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
3391 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
149daaf3 | 3392 | if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) |
b789ef51 CL |
3393 | /* Enable fast mode */ |
3394 | s->flags |= __CMPXCHG_DOUBLE; | |
3395 | #endif | |
3396 | ||
3b89d7d8 DR |
3397 | /* |
3398 | * The larger the object size is, the more pages we want on the partial | |
3399 | * list to avoid pounding the page allocator excessively. | |
3400 | */ | |
49e22585 CL |
3401 | set_min_partial(s, ilog2(s->size) / 2); |
3402 | ||
3403 | /* | |
3404 | * cpu_partial determined the maximum number of objects kept in the | |
3405 | * per cpu partial lists of a processor. | |
3406 | * | |
3407 | * Per cpu partial lists mainly contain slabs that just have one | |
3408 | * object freed. If they are used for allocation then they can be | |
3409 | * filled up again with minimal effort. The slab will never hit the | |
3410 | * per node partial lists and therefore no locking will be required. | |
3411 | * | |
3412 | * This setting also determines | |
3413 | * | |
3414 | * A) The number of objects from per cpu partial slabs dumped to the | |
3415 | * per node list when we reach the limit. | |
9f264904 | 3416 | * B) The number of objects in cpu partial slabs to extract from the |
d0e0ac97 CG |
3417 | * per node list when we run out of per cpu objects. We only fetch |
3418 | * 50% to keep some capacity around for frees. | |
49e22585 | 3419 | */ |
345c905d | 3420 | if (!kmem_cache_has_cpu_partial(s)) |
8f1e33da CL |
3421 | s->cpu_partial = 0; |
3422 | else if (s->size >= PAGE_SIZE) | |
49e22585 CL |
3423 | s->cpu_partial = 2; |
3424 | else if (s->size >= 1024) | |
3425 | s->cpu_partial = 6; | |
3426 | else if (s->size >= 256) | |
3427 | s->cpu_partial = 13; | |
3428 | else | |
3429 | s->cpu_partial = 30; | |
3430 | ||
81819f0f | 3431 | #ifdef CONFIG_NUMA |
e2cb96b7 | 3432 | s->remote_node_defrag_ratio = 1000; |
81819f0f | 3433 | #endif |
55136592 | 3434 | if (!init_kmem_cache_nodes(s)) |
dfb4f096 | 3435 | goto error; |
81819f0f | 3436 | |
55136592 | 3437 | if (alloc_kmem_cache_cpus(s)) |
278b1bb1 | 3438 | return 0; |
ff12059e | 3439 | |
4c93c355 | 3440 | free_kmem_cache_nodes(s); |
81819f0f CL |
3441 | error: |
3442 | if (flags & SLAB_PANIC) | |
3443 | panic("Cannot create slab %s size=%lu realsize=%u " | |
3444 | "order=%u offset=%u flags=%lx\n", | |
d0e0ac97 CG |
3445 | s->name, (unsigned long)s->size, s->size, |
3446 | oo_order(s->oo), s->offset, flags); | |
278b1bb1 | 3447 | return -EINVAL; |
81819f0f | 3448 | } |
81819f0f | 3449 | |
33b12c38 CL |
3450 | static void list_slab_objects(struct kmem_cache *s, struct page *page, |
3451 | const char *text) | |
3452 | { | |
3453 | #ifdef CONFIG_SLUB_DEBUG | |
3454 | void *addr = page_address(page); | |
3455 | void *p; | |
a5dd5c11 NK |
3456 | unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) * |
3457 | sizeof(long), GFP_ATOMIC); | |
bbd7d57b ED |
3458 | if (!map) |
3459 | return; | |
945cf2b6 | 3460 | slab_err(s, page, text, s->name); |
33b12c38 | 3461 | slab_lock(page); |
33b12c38 | 3462 | |
5f80b13a | 3463 | get_map(s, page, map); |
33b12c38 CL |
3464 | for_each_object(p, s, addr, page->objects) { |
3465 | ||
3466 | if (!test_bit(slab_index(p, s, addr), map)) { | |
f9f58285 | 3467 | pr_err("INFO: Object 0x%p @offset=%tu\n", p, p - addr); |
33b12c38 CL |
3468 | print_tracking(s, p); |
3469 | } | |
3470 | } | |
3471 | slab_unlock(page); | |
bbd7d57b | 3472 | kfree(map); |
33b12c38 CL |
3473 | #endif |
3474 | } | |
3475 | ||
81819f0f | 3476 | /* |
599870b1 | 3477 | * Attempt to free all partial slabs on a node. |
52b4b950 DS |
3478 | * This is called from __kmem_cache_shutdown(). We must take list_lock |
3479 | * because sysfs file might still access partial list after the shutdowning. | |
81819f0f | 3480 | */ |
599870b1 | 3481 | static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) |
81819f0f | 3482 | { |
81819f0f CL |
3483 | struct page *page, *h; |
3484 | ||
52b4b950 DS |
3485 | BUG_ON(irqs_disabled()); |
3486 | spin_lock_irq(&n->list_lock); | |
33b12c38 | 3487 | list_for_each_entry_safe(page, h, &n->partial, lru) { |
81819f0f | 3488 | if (!page->inuse) { |
52b4b950 | 3489 | remove_partial(n, page); |
81819f0f | 3490 | discard_slab(s, page); |
33b12c38 CL |
3491 | } else { |
3492 | list_slab_objects(s, page, | |
52b4b950 | 3493 | "Objects remaining in %s on __kmem_cache_shutdown()"); |
599870b1 | 3494 | } |
33b12c38 | 3495 | } |
52b4b950 | 3496 | spin_unlock_irq(&n->list_lock); |
81819f0f CL |
3497 | } |
3498 | ||
3499 | /* | |
672bba3a | 3500 | * Release all resources used by a slab cache. |
81819f0f | 3501 | */ |
52b4b950 | 3502 | int __kmem_cache_shutdown(struct kmem_cache *s) |
81819f0f CL |
3503 | { |
3504 | int node; | |
fa45dc25 | 3505 | struct kmem_cache_node *n; |
81819f0f CL |
3506 | |
3507 | flush_all(s); | |
81819f0f | 3508 | /* Attempt to free all objects */ |
fa45dc25 | 3509 | for_each_kmem_cache_node(s, node, n) { |
599870b1 CL |
3510 | free_partial(s, n); |
3511 | if (n->nr_partial || slabs_node(s, node)) | |
81819f0f CL |
3512 | return 1; |
3513 | } | |
81819f0f CL |
3514 | return 0; |
3515 | } | |
3516 | ||
81819f0f CL |
3517 | /******************************************************************** |
3518 | * Kmalloc subsystem | |
3519 | *******************************************************************/ | |
3520 | ||
81819f0f CL |
3521 | static int __init setup_slub_min_order(char *str) |
3522 | { | |
06428780 | 3523 | get_option(&str, &slub_min_order); |
81819f0f CL |
3524 | |
3525 | return 1; | |
3526 | } | |
3527 | ||
3528 | __setup("slub_min_order=", setup_slub_min_order); | |
3529 | ||
3530 | static int __init setup_slub_max_order(char *str) | |
3531 | { | |
06428780 | 3532 | get_option(&str, &slub_max_order); |
818cf590 | 3533 | slub_max_order = min(slub_max_order, MAX_ORDER - 1); |
81819f0f CL |
3534 | |
3535 | return 1; | |
3536 | } | |
3537 | ||
3538 | __setup("slub_max_order=", setup_slub_max_order); | |
3539 | ||
3540 | static int __init setup_slub_min_objects(char *str) | |
3541 | { | |
06428780 | 3542 | get_option(&str, &slub_min_objects); |
81819f0f CL |
3543 | |
3544 | return 1; | |
3545 | } | |
3546 | ||
3547 | __setup("slub_min_objects=", setup_slub_min_objects); | |
3548 | ||
81819f0f CL |
3549 | void *__kmalloc(size_t size, gfp_t flags) |
3550 | { | |
aadb4bc4 | 3551 | struct kmem_cache *s; |
5b882be4 | 3552 | void *ret; |
81819f0f | 3553 | |
95a05b42 | 3554 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) |
eada35ef | 3555 | return kmalloc_large(size, flags); |
aadb4bc4 | 3556 | |
2c59dd65 | 3557 | s = kmalloc_slab(size, flags); |
aadb4bc4 CL |
3558 | |
3559 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
3560 | return s; |
3561 | ||
2b847c3c | 3562 | ret = slab_alloc(s, flags, _RET_IP_); |
5b882be4 | 3563 | |
ca2b84cb | 3564 | trace_kmalloc(_RET_IP_, ret, size, s->size, flags); |
5b882be4 | 3565 | |
0316bec2 AR |
3566 | kasan_kmalloc(s, ret, size); |
3567 | ||
5b882be4 | 3568 | return ret; |
81819f0f CL |
3569 | } |
3570 | EXPORT_SYMBOL(__kmalloc); | |
3571 | ||
5d1f57e4 | 3572 | #ifdef CONFIG_NUMA |
f619cfe1 CL |
3573 | static void *kmalloc_large_node(size_t size, gfp_t flags, int node) |
3574 | { | |
b1eeab67 | 3575 | struct page *page; |
e4f7c0b4 | 3576 | void *ptr = NULL; |
f619cfe1 | 3577 | |
52383431 VD |
3578 | flags |= __GFP_COMP | __GFP_NOTRACK; |
3579 | page = alloc_kmem_pages_node(node, flags, get_order(size)); | |
f619cfe1 | 3580 | if (page) |
e4f7c0b4 CM |
3581 | ptr = page_address(page); |
3582 | ||
d56791b3 | 3583 | kmalloc_large_node_hook(ptr, size, flags); |
e4f7c0b4 | 3584 | return ptr; |
f619cfe1 CL |
3585 | } |
3586 | ||
81819f0f CL |
3587 | void *__kmalloc_node(size_t size, gfp_t flags, int node) |
3588 | { | |
aadb4bc4 | 3589 | struct kmem_cache *s; |
5b882be4 | 3590 | void *ret; |
81819f0f | 3591 | |
95a05b42 | 3592 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { |
5b882be4 EGM |
3593 | ret = kmalloc_large_node(size, flags, node); |
3594 | ||
ca2b84cb EGM |
3595 | trace_kmalloc_node(_RET_IP_, ret, |
3596 | size, PAGE_SIZE << get_order(size), | |
3597 | flags, node); | |
5b882be4 EGM |
3598 | |
3599 | return ret; | |
3600 | } | |
aadb4bc4 | 3601 | |
2c59dd65 | 3602 | s = kmalloc_slab(size, flags); |
aadb4bc4 CL |
3603 | |
3604 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
3605 | return s; |
3606 | ||
2b847c3c | 3607 | ret = slab_alloc_node(s, flags, node, _RET_IP_); |
5b882be4 | 3608 | |
ca2b84cb | 3609 | trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node); |
5b882be4 | 3610 | |
0316bec2 AR |
3611 | kasan_kmalloc(s, ret, size); |
3612 | ||
5b882be4 | 3613 | return ret; |
81819f0f CL |
3614 | } |
3615 | EXPORT_SYMBOL(__kmalloc_node); | |
3616 | #endif | |
3617 | ||
0316bec2 | 3618 | static size_t __ksize(const void *object) |
81819f0f | 3619 | { |
272c1d21 | 3620 | struct page *page; |
81819f0f | 3621 | |
ef8b4520 | 3622 | if (unlikely(object == ZERO_SIZE_PTR)) |
272c1d21 CL |
3623 | return 0; |
3624 | ||
294a80a8 | 3625 | page = virt_to_head_page(object); |
294a80a8 | 3626 | |
76994412 PE |
3627 | if (unlikely(!PageSlab(page))) { |
3628 | WARN_ON(!PageCompound(page)); | |
294a80a8 | 3629 | return PAGE_SIZE << compound_order(page); |
76994412 | 3630 | } |
81819f0f | 3631 | |
1b4f59e3 | 3632 | return slab_ksize(page->slab_cache); |
81819f0f | 3633 | } |
0316bec2 AR |
3634 | |
3635 | size_t ksize(const void *object) | |
3636 | { | |
3637 | size_t size = __ksize(object); | |
3638 | /* We assume that ksize callers could use whole allocated area, | |
3639 | so we need unpoison this area. */ | |
3640 | kasan_krealloc(object, size); | |
3641 | return size; | |
3642 | } | |
b1aabecd | 3643 | EXPORT_SYMBOL(ksize); |
81819f0f CL |
3644 | |
3645 | void kfree(const void *x) | |
3646 | { | |
81819f0f | 3647 | struct page *page; |
5bb983b0 | 3648 | void *object = (void *)x; |
81819f0f | 3649 | |
2121db74 PE |
3650 | trace_kfree(_RET_IP_, x); |
3651 | ||
2408c550 | 3652 | if (unlikely(ZERO_OR_NULL_PTR(x))) |
81819f0f CL |
3653 | return; |
3654 | ||
b49af68f | 3655 | page = virt_to_head_page(x); |
aadb4bc4 | 3656 | if (unlikely(!PageSlab(page))) { |
0937502a | 3657 | BUG_ON(!PageCompound(page)); |
d56791b3 | 3658 | kfree_hook(x); |
52383431 | 3659 | __free_kmem_pages(page, compound_order(page)); |
aadb4bc4 CL |
3660 | return; |
3661 | } | |
81084651 | 3662 | slab_free(page->slab_cache, page, object, NULL, 1, _RET_IP_); |
81819f0f CL |
3663 | } |
3664 | EXPORT_SYMBOL(kfree); | |
3665 | ||
832f37f5 VD |
3666 | #define SHRINK_PROMOTE_MAX 32 |
3667 | ||
2086d26a | 3668 | /* |
832f37f5 VD |
3669 | * kmem_cache_shrink discards empty slabs and promotes the slabs filled |
3670 | * up most to the head of the partial lists. New allocations will then | |
3671 | * fill those up and thus they can be removed from the partial lists. | |
672bba3a CL |
3672 | * |
3673 | * The slabs with the least items are placed last. This results in them | |
3674 | * being allocated from last increasing the chance that the last objects | |
3675 | * are freed in them. | |
2086d26a | 3676 | */ |
d6e0b7fa | 3677 | int __kmem_cache_shrink(struct kmem_cache *s, bool deactivate) |
2086d26a CL |
3678 | { |
3679 | int node; | |
3680 | int i; | |
3681 | struct kmem_cache_node *n; | |
3682 | struct page *page; | |
3683 | struct page *t; | |
832f37f5 VD |
3684 | struct list_head discard; |
3685 | struct list_head promote[SHRINK_PROMOTE_MAX]; | |
2086d26a | 3686 | unsigned long flags; |
ce3712d7 | 3687 | int ret = 0; |
2086d26a | 3688 | |
d6e0b7fa VD |
3689 | if (deactivate) { |
3690 | /* | |
3691 | * Disable empty slabs caching. Used to avoid pinning offline | |
3692 | * memory cgroups by kmem pages that can be freed. | |
3693 | */ | |
3694 | s->cpu_partial = 0; | |
3695 | s->min_partial = 0; | |
3696 | ||
3697 | /* | |
3698 | * s->cpu_partial is checked locklessly (see put_cpu_partial), | |
3699 | * so we have to make sure the change is visible. | |
3700 | */ | |
3701 | kick_all_cpus_sync(); | |
3702 | } | |
3703 | ||
2086d26a | 3704 | flush_all(s); |
fa45dc25 | 3705 | for_each_kmem_cache_node(s, node, n) { |
832f37f5 VD |
3706 | INIT_LIST_HEAD(&discard); |
3707 | for (i = 0; i < SHRINK_PROMOTE_MAX; i++) | |
3708 | INIT_LIST_HEAD(promote + i); | |
2086d26a CL |
3709 | |
3710 | spin_lock_irqsave(&n->list_lock, flags); | |
3711 | ||
3712 | /* | |
832f37f5 | 3713 | * Build lists of slabs to discard or promote. |
2086d26a | 3714 | * |
672bba3a CL |
3715 | * Note that concurrent frees may occur while we hold the |
3716 | * list_lock. page->inuse here is the upper limit. | |
2086d26a CL |
3717 | */ |
3718 | list_for_each_entry_safe(page, t, &n->partial, lru) { | |
832f37f5 VD |
3719 | int free = page->objects - page->inuse; |
3720 | ||
3721 | /* Do not reread page->inuse */ | |
3722 | barrier(); | |
3723 | ||
3724 | /* We do not keep full slabs on the list */ | |
3725 | BUG_ON(free <= 0); | |
3726 | ||
3727 | if (free == page->objects) { | |
3728 | list_move(&page->lru, &discard); | |
69cb8e6b | 3729 | n->nr_partial--; |
832f37f5 VD |
3730 | } else if (free <= SHRINK_PROMOTE_MAX) |
3731 | list_move(&page->lru, promote + free - 1); | |
2086d26a CL |
3732 | } |
3733 | ||
2086d26a | 3734 | /* |
832f37f5 VD |
3735 | * Promote the slabs filled up most to the head of the |
3736 | * partial list. | |
2086d26a | 3737 | */ |
832f37f5 VD |
3738 | for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) |
3739 | list_splice(promote + i, &n->partial); | |
2086d26a | 3740 | |
2086d26a | 3741 | spin_unlock_irqrestore(&n->list_lock, flags); |
69cb8e6b CL |
3742 | |
3743 | /* Release empty slabs */ | |
832f37f5 | 3744 | list_for_each_entry_safe(page, t, &discard, lru) |
69cb8e6b | 3745 | discard_slab(s, page); |
ce3712d7 VD |
3746 | |
3747 | if (slabs_node(s, node)) | |
3748 | ret = 1; | |
2086d26a CL |
3749 | } |
3750 | ||
ce3712d7 | 3751 | return ret; |
2086d26a | 3752 | } |
2086d26a | 3753 | |
b9049e23 YG |
3754 | static int slab_mem_going_offline_callback(void *arg) |
3755 | { | |
3756 | struct kmem_cache *s; | |
3757 | ||
18004c5d | 3758 | mutex_lock(&slab_mutex); |
b9049e23 | 3759 | list_for_each_entry(s, &slab_caches, list) |
d6e0b7fa | 3760 | __kmem_cache_shrink(s, false); |
18004c5d | 3761 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
3762 | |
3763 | return 0; | |
3764 | } | |
3765 | ||
3766 | static void slab_mem_offline_callback(void *arg) | |
3767 | { | |
3768 | struct kmem_cache_node *n; | |
3769 | struct kmem_cache *s; | |
3770 | struct memory_notify *marg = arg; | |
3771 | int offline_node; | |
3772 | ||
b9d5ab25 | 3773 | offline_node = marg->status_change_nid_normal; |
b9049e23 YG |
3774 | |
3775 | /* | |
3776 | * If the node still has available memory. we need kmem_cache_node | |
3777 | * for it yet. | |
3778 | */ | |
3779 | if (offline_node < 0) | |
3780 | return; | |
3781 | ||
18004c5d | 3782 | mutex_lock(&slab_mutex); |
b9049e23 YG |
3783 | list_for_each_entry(s, &slab_caches, list) { |
3784 | n = get_node(s, offline_node); | |
3785 | if (n) { | |
3786 | /* | |
3787 | * if n->nr_slabs > 0, slabs still exist on the node | |
3788 | * that is going down. We were unable to free them, | |
c9404c9c | 3789 | * and offline_pages() function shouldn't call this |
b9049e23 YG |
3790 | * callback. So, we must fail. |
3791 | */ | |
0f389ec6 | 3792 | BUG_ON(slabs_node(s, offline_node)); |
b9049e23 YG |
3793 | |
3794 | s->node[offline_node] = NULL; | |
8de66a0c | 3795 | kmem_cache_free(kmem_cache_node, n); |
b9049e23 YG |
3796 | } |
3797 | } | |
18004c5d | 3798 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
3799 | } |
3800 | ||
3801 | static int slab_mem_going_online_callback(void *arg) | |
3802 | { | |
3803 | struct kmem_cache_node *n; | |
3804 | struct kmem_cache *s; | |
3805 | struct memory_notify *marg = arg; | |
b9d5ab25 | 3806 | int nid = marg->status_change_nid_normal; |
b9049e23 YG |
3807 | int ret = 0; |
3808 | ||
3809 | /* | |
3810 | * If the node's memory is already available, then kmem_cache_node is | |
3811 | * already created. Nothing to do. | |
3812 | */ | |
3813 | if (nid < 0) | |
3814 | return 0; | |
3815 | ||
3816 | /* | |
0121c619 | 3817 | * We are bringing a node online. No memory is available yet. We must |
b9049e23 YG |
3818 | * allocate a kmem_cache_node structure in order to bring the node |
3819 | * online. | |
3820 | */ | |
18004c5d | 3821 | mutex_lock(&slab_mutex); |
b9049e23 YG |
3822 | list_for_each_entry(s, &slab_caches, list) { |
3823 | /* | |
3824 | * XXX: kmem_cache_alloc_node will fallback to other nodes | |
3825 | * since memory is not yet available from the node that | |
3826 | * is brought up. | |
3827 | */ | |
8de66a0c | 3828 | n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); |
b9049e23 YG |
3829 | if (!n) { |
3830 | ret = -ENOMEM; | |
3831 | goto out; | |
3832 | } | |
4053497d | 3833 | init_kmem_cache_node(n); |
b9049e23 YG |
3834 | s->node[nid] = n; |
3835 | } | |
3836 | out: | |
18004c5d | 3837 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
3838 | return ret; |
3839 | } | |
3840 | ||
3841 | static int slab_memory_callback(struct notifier_block *self, | |
3842 | unsigned long action, void *arg) | |
3843 | { | |
3844 | int ret = 0; | |
3845 | ||
3846 | switch (action) { | |
3847 | case MEM_GOING_ONLINE: | |
3848 | ret = slab_mem_going_online_callback(arg); | |
3849 | break; | |
3850 | case MEM_GOING_OFFLINE: | |
3851 | ret = slab_mem_going_offline_callback(arg); | |
3852 | break; | |
3853 | case MEM_OFFLINE: | |
3854 | case MEM_CANCEL_ONLINE: | |
3855 | slab_mem_offline_callback(arg); | |
3856 | break; | |
3857 | case MEM_ONLINE: | |
3858 | case MEM_CANCEL_OFFLINE: | |
3859 | break; | |
3860 | } | |
dc19f9db KH |
3861 | if (ret) |
3862 | ret = notifier_from_errno(ret); | |
3863 | else | |
3864 | ret = NOTIFY_OK; | |
b9049e23 YG |
3865 | return ret; |
3866 | } | |
3867 | ||
3ac38faa AM |
3868 | static struct notifier_block slab_memory_callback_nb = { |
3869 | .notifier_call = slab_memory_callback, | |
3870 | .priority = SLAB_CALLBACK_PRI, | |
3871 | }; | |
b9049e23 | 3872 | |
81819f0f CL |
3873 | /******************************************************************** |
3874 | * Basic setup of slabs | |
3875 | *******************************************************************/ | |
3876 | ||
51df1142 CL |
3877 | /* |
3878 | * Used for early kmem_cache structures that were allocated using | |
dffb4d60 CL |
3879 | * the page allocator. Allocate them properly then fix up the pointers |
3880 | * that may be pointing to the wrong kmem_cache structure. | |
51df1142 CL |
3881 | */ |
3882 | ||
dffb4d60 | 3883 | static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) |
51df1142 CL |
3884 | { |
3885 | int node; | |
dffb4d60 | 3886 | struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); |
fa45dc25 | 3887 | struct kmem_cache_node *n; |
51df1142 | 3888 | |
dffb4d60 | 3889 | memcpy(s, static_cache, kmem_cache->object_size); |
51df1142 | 3890 | |
7d557b3c GC |
3891 | /* |
3892 | * This runs very early, and only the boot processor is supposed to be | |
3893 | * up. Even if it weren't true, IRQs are not up so we couldn't fire | |
3894 | * IPIs around. | |
3895 | */ | |
3896 | __flush_cpu_slab(s, smp_processor_id()); | |
fa45dc25 | 3897 | for_each_kmem_cache_node(s, node, n) { |
51df1142 CL |
3898 | struct page *p; |
3899 | ||
fa45dc25 CL |
3900 | list_for_each_entry(p, &n->partial, lru) |
3901 | p->slab_cache = s; | |
51df1142 | 3902 | |
607bf324 | 3903 | #ifdef CONFIG_SLUB_DEBUG |
fa45dc25 CL |
3904 | list_for_each_entry(p, &n->full, lru) |
3905 | p->slab_cache = s; | |
51df1142 | 3906 | #endif |
51df1142 | 3907 | } |
f7ce3190 | 3908 | slab_init_memcg_params(s); |
dffb4d60 CL |
3909 | list_add(&s->list, &slab_caches); |
3910 | return s; | |
51df1142 CL |
3911 | } |
3912 | ||
81819f0f CL |
3913 | void __init kmem_cache_init(void) |
3914 | { | |
dffb4d60 CL |
3915 | static __initdata struct kmem_cache boot_kmem_cache, |
3916 | boot_kmem_cache_node; | |
51df1142 | 3917 | |
fc8d8620 SG |
3918 | if (debug_guardpage_minorder()) |
3919 | slub_max_order = 0; | |
3920 | ||
dffb4d60 CL |
3921 | kmem_cache_node = &boot_kmem_cache_node; |
3922 | kmem_cache = &boot_kmem_cache; | |
51df1142 | 3923 | |
dffb4d60 CL |
3924 | create_boot_cache(kmem_cache_node, "kmem_cache_node", |
3925 | sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN); | |
b9049e23 | 3926 | |
3ac38faa | 3927 | register_hotmemory_notifier(&slab_memory_callback_nb); |
81819f0f CL |
3928 | |
3929 | /* Able to allocate the per node structures */ | |
3930 | slab_state = PARTIAL; | |
3931 | ||
dffb4d60 CL |
3932 | create_boot_cache(kmem_cache, "kmem_cache", |
3933 | offsetof(struct kmem_cache, node) + | |
3934 | nr_node_ids * sizeof(struct kmem_cache_node *), | |
3935 | SLAB_HWCACHE_ALIGN); | |
8a13a4cc | 3936 | |
dffb4d60 | 3937 | kmem_cache = bootstrap(&boot_kmem_cache); |
81819f0f | 3938 | |
51df1142 CL |
3939 | /* |
3940 | * Allocate kmem_cache_node properly from the kmem_cache slab. | |
3941 | * kmem_cache_node is separately allocated so no need to | |
3942 | * update any list pointers. | |
3943 | */ | |
dffb4d60 | 3944 | kmem_cache_node = bootstrap(&boot_kmem_cache_node); |
51df1142 CL |
3945 | |
3946 | /* Now we can use the kmem_cache to allocate kmalloc slabs */ | |
34cc6990 | 3947 | setup_kmalloc_cache_index_table(); |
f97d5f63 | 3948 | create_kmalloc_caches(0); |
81819f0f CL |
3949 | |
3950 | #ifdef CONFIG_SMP | |
3951 | register_cpu_notifier(&slab_notifier); | |
9dfc6e68 | 3952 | #endif |
81819f0f | 3953 | |
f9f58285 | 3954 | pr_info("SLUB: HWalign=%d, Order=%d-%d, MinObjects=%d, CPUs=%d, Nodes=%d\n", |
f97d5f63 | 3955 | cache_line_size(), |
81819f0f CL |
3956 | slub_min_order, slub_max_order, slub_min_objects, |
3957 | nr_cpu_ids, nr_node_ids); | |
3958 | } | |
3959 | ||
7e85ee0c PE |
3960 | void __init kmem_cache_init_late(void) |
3961 | { | |
7e85ee0c PE |
3962 | } |
3963 | ||
2633d7a0 | 3964 | struct kmem_cache * |
a44cb944 VD |
3965 | __kmem_cache_alias(const char *name, size_t size, size_t align, |
3966 | unsigned long flags, void (*ctor)(void *)) | |
81819f0f | 3967 | { |
426589f5 | 3968 | struct kmem_cache *s, *c; |
81819f0f | 3969 | |
a44cb944 | 3970 | s = find_mergeable(size, align, flags, name, ctor); |
81819f0f CL |
3971 | if (s) { |
3972 | s->refcount++; | |
84d0ddd6 | 3973 | |
81819f0f CL |
3974 | /* |
3975 | * Adjust the object sizes so that we clear | |
3976 | * the complete object on kzalloc. | |
3977 | */ | |
3b0efdfa | 3978 | s->object_size = max(s->object_size, (int)size); |
81819f0f | 3979 | s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *))); |
6446faa2 | 3980 | |
426589f5 | 3981 | for_each_memcg_cache(c, s) { |
84d0ddd6 VD |
3982 | c->object_size = s->object_size; |
3983 | c->inuse = max_t(int, c->inuse, | |
3984 | ALIGN(size, sizeof(void *))); | |
3985 | } | |
3986 | ||
7b8f3b66 | 3987 | if (sysfs_slab_alias(s, name)) { |
7b8f3b66 | 3988 | s->refcount--; |
cbb79694 | 3989 | s = NULL; |
7b8f3b66 | 3990 | } |
a0e1d1be | 3991 | } |
6446faa2 | 3992 | |
cbb79694 CL |
3993 | return s; |
3994 | } | |
84c1cf62 | 3995 | |
8a13a4cc | 3996 | int __kmem_cache_create(struct kmem_cache *s, unsigned long flags) |
cbb79694 | 3997 | { |
aac3a166 PE |
3998 | int err; |
3999 | ||
4000 | err = kmem_cache_open(s, flags); | |
4001 | if (err) | |
4002 | return err; | |
20cea968 | 4003 | |
45530c44 CL |
4004 | /* Mutex is not taken during early boot */ |
4005 | if (slab_state <= UP) | |
4006 | return 0; | |
4007 | ||
107dab5c | 4008 | memcg_propagate_slab_attrs(s); |
aac3a166 | 4009 | err = sysfs_slab_add(s); |
aac3a166 | 4010 | if (err) |
52b4b950 | 4011 | __kmem_cache_release(s); |
20cea968 | 4012 | |
aac3a166 | 4013 | return err; |
81819f0f | 4014 | } |
81819f0f | 4015 | |
81819f0f | 4016 | #ifdef CONFIG_SMP |
81819f0f | 4017 | /* |
672bba3a CL |
4018 | * Use the cpu notifier to insure that the cpu slabs are flushed when |
4019 | * necessary. | |
81819f0f | 4020 | */ |
0db0628d | 4021 | static int slab_cpuup_callback(struct notifier_block *nfb, |
81819f0f CL |
4022 | unsigned long action, void *hcpu) |
4023 | { | |
4024 | long cpu = (long)hcpu; | |
5b95a4ac CL |
4025 | struct kmem_cache *s; |
4026 | unsigned long flags; | |
81819f0f CL |
4027 | |
4028 | switch (action) { | |
4029 | case CPU_UP_CANCELED: | |
8bb78442 | 4030 | case CPU_UP_CANCELED_FROZEN: |
81819f0f | 4031 | case CPU_DEAD: |
8bb78442 | 4032 | case CPU_DEAD_FROZEN: |
18004c5d | 4033 | mutex_lock(&slab_mutex); |
5b95a4ac CL |
4034 | list_for_each_entry(s, &slab_caches, list) { |
4035 | local_irq_save(flags); | |
4036 | __flush_cpu_slab(s, cpu); | |
4037 | local_irq_restore(flags); | |
4038 | } | |
18004c5d | 4039 | mutex_unlock(&slab_mutex); |
81819f0f CL |
4040 | break; |
4041 | default: | |
4042 | break; | |
4043 | } | |
4044 | return NOTIFY_OK; | |
4045 | } | |
4046 | ||
0db0628d | 4047 | static struct notifier_block slab_notifier = { |
3adbefee | 4048 | .notifier_call = slab_cpuup_callback |
06428780 | 4049 | }; |
81819f0f CL |
4050 | |
4051 | #endif | |
4052 | ||
ce71e27c | 4053 | void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller) |
81819f0f | 4054 | { |
aadb4bc4 | 4055 | struct kmem_cache *s; |
94b528d0 | 4056 | void *ret; |
aadb4bc4 | 4057 | |
95a05b42 | 4058 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) |
eada35ef PE |
4059 | return kmalloc_large(size, gfpflags); |
4060 | ||
2c59dd65 | 4061 | s = kmalloc_slab(size, gfpflags); |
81819f0f | 4062 | |
2408c550 | 4063 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 4064 | return s; |
81819f0f | 4065 | |
2b847c3c | 4066 | ret = slab_alloc(s, gfpflags, caller); |
94b528d0 | 4067 | |
25985edc | 4068 | /* Honor the call site pointer we received. */ |
ca2b84cb | 4069 | trace_kmalloc(caller, ret, size, s->size, gfpflags); |
94b528d0 EGM |
4070 | |
4071 | return ret; | |
81819f0f CL |
4072 | } |
4073 | ||
5d1f57e4 | 4074 | #ifdef CONFIG_NUMA |
81819f0f | 4075 | void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, |
ce71e27c | 4076 | int node, unsigned long caller) |
81819f0f | 4077 | { |
aadb4bc4 | 4078 | struct kmem_cache *s; |
94b528d0 | 4079 | void *ret; |
aadb4bc4 | 4080 | |
95a05b42 | 4081 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { |
d3e14aa3 XF |
4082 | ret = kmalloc_large_node(size, gfpflags, node); |
4083 | ||
4084 | trace_kmalloc_node(caller, ret, | |
4085 | size, PAGE_SIZE << get_order(size), | |
4086 | gfpflags, node); | |
4087 | ||
4088 | return ret; | |
4089 | } | |
eada35ef | 4090 | |
2c59dd65 | 4091 | s = kmalloc_slab(size, gfpflags); |
81819f0f | 4092 | |
2408c550 | 4093 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 4094 | return s; |
81819f0f | 4095 | |
2b847c3c | 4096 | ret = slab_alloc_node(s, gfpflags, node, caller); |
94b528d0 | 4097 | |
25985edc | 4098 | /* Honor the call site pointer we received. */ |
ca2b84cb | 4099 | trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node); |
94b528d0 EGM |
4100 | |
4101 | return ret; | |
81819f0f | 4102 | } |
5d1f57e4 | 4103 | #endif |
81819f0f | 4104 | |
ab4d5ed5 | 4105 | #ifdef CONFIG_SYSFS |
205ab99d CL |
4106 | static int count_inuse(struct page *page) |
4107 | { | |
4108 | return page->inuse; | |
4109 | } | |
4110 | ||
4111 | static int count_total(struct page *page) | |
4112 | { | |
4113 | return page->objects; | |
4114 | } | |
ab4d5ed5 | 4115 | #endif |
205ab99d | 4116 | |
ab4d5ed5 | 4117 | #ifdef CONFIG_SLUB_DEBUG |
434e245d CL |
4118 | static int validate_slab(struct kmem_cache *s, struct page *page, |
4119 | unsigned long *map) | |
53e15af0 CL |
4120 | { |
4121 | void *p; | |
a973e9dd | 4122 | void *addr = page_address(page); |
53e15af0 CL |
4123 | |
4124 | if (!check_slab(s, page) || | |
4125 | !on_freelist(s, page, NULL)) | |
4126 | return 0; | |
4127 | ||
4128 | /* Now we know that a valid freelist exists */ | |
39b26464 | 4129 | bitmap_zero(map, page->objects); |
53e15af0 | 4130 | |
5f80b13a CL |
4131 | get_map(s, page, map); |
4132 | for_each_object(p, s, addr, page->objects) { | |
4133 | if (test_bit(slab_index(p, s, addr), map)) | |
4134 | if (!check_object(s, page, p, SLUB_RED_INACTIVE)) | |
4135 | return 0; | |
53e15af0 CL |
4136 | } |
4137 | ||
224a88be | 4138 | for_each_object(p, s, addr, page->objects) |
7656c72b | 4139 | if (!test_bit(slab_index(p, s, addr), map)) |
37d57443 | 4140 | if (!check_object(s, page, p, SLUB_RED_ACTIVE)) |
53e15af0 CL |
4141 | return 0; |
4142 | return 1; | |
4143 | } | |
4144 | ||
434e245d CL |
4145 | static void validate_slab_slab(struct kmem_cache *s, struct page *page, |
4146 | unsigned long *map) | |
53e15af0 | 4147 | { |
881db7fb CL |
4148 | slab_lock(page); |
4149 | validate_slab(s, page, map); | |
4150 | slab_unlock(page); | |
53e15af0 CL |
4151 | } |
4152 | ||
434e245d CL |
4153 | static int validate_slab_node(struct kmem_cache *s, |
4154 | struct kmem_cache_node *n, unsigned long *map) | |
53e15af0 CL |
4155 | { |
4156 | unsigned long count = 0; | |
4157 | struct page *page; | |
4158 | unsigned long flags; | |
4159 | ||
4160 | spin_lock_irqsave(&n->list_lock, flags); | |
4161 | ||
4162 | list_for_each_entry(page, &n->partial, lru) { | |
434e245d | 4163 | validate_slab_slab(s, page, map); |
53e15af0 CL |
4164 | count++; |
4165 | } | |
4166 | if (count != n->nr_partial) | |
f9f58285 FF |
4167 | pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", |
4168 | s->name, count, n->nr_partial); | |
53e15af0 CL |
4169 | |
4170 | if (!(s->flags & SLAB_STORE_USER)) | |
4171 | goto out; | |
4172 | ||
4173 | list_for_each_entry(page, &n->full, lru) { | |
434e245d | 4174 | validate_slab_slab(s, page, map); |
53e15af0 CL |
4175 | count++; |
4176 | } | |
4177 | if (count != atomic_long_read(&n->nr_slabs)) | |
f9f58285 FF |
4178 | pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", |
4179 | s->name, count, atomic_long_read(&n->nr_slabs)); | |
53e15af0 CL |
4180 | |
4181 | out: | |
4182 | spin_unlock_irqrestore(&n->list_lock, flags); | |
4183 | return count; | |
4184 | } | |
4185 | ||
434e245d | 4186 | static long validate_slab_cache(struct kmem_cache *s) |
53e15af0 CL |
4187 | { |
4188 | int node; | |
4189 | unsigned long count = 0; | |
205ab99d | 4190 | unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) * |
434e245d | 4191 | sizeof(unsigned long), GFP_KERNEL); |
fa45dc25 | 4192 | struct kmem_cache_node *n; |
434e245d CL |
4193 | |
4194 | if (!map) | |
4195 | return -ENOMEM; | |
53e15af0 CL |
4196 | |
4197 | flush_all(s); | |
fa45dc25 | 4198 | for_each_kmem_cache_node(s, node, n) |
434e245d | 4199 | count += validate_slab_node(s, n, map); |
434e245d | 4200 | kfree(map); |
53e15af0 CL |
4201 | return count; |
4202 | } | |
88a420e4 | 4203 | /* |
672bba3a | 4204 | * Generate lists of code addresses where slabcache objects are allocated |
88a420e4 CL |
4205 | * and freed. |
4206 | */ | |
4207 | ||
4208 | struct location { | |
4209 | unsigned long count; | |
ce71e27c | 4210 | unsigned long addr; |
45edfa58 CL |
4211 | long long sum_time; |
4212 | long min_time; | |
4213 | long max_time; | |
4214 | long min_pid; | |
4215 | long max_pid; | |
174596a0 | 4216 | DECLARE_BITMAP(cpus, NR_CPUS); |
45edfa58 | 4217 | nodemask_t nodes; |
88a420e4 CL |
4218 | }; |
4219 | ||
4220 | struct loc_track { | |
4221 | unsigned long max; | |
4222 | unsigned long count; | |
4223 | struct location *loc; | |
4224 | }; | |
4225 | ||
4226 | static void free_loc_track(struct loc_track *t) | |
4227 | { | |
4228 | if (t->max) | |
4229 | free_pages((unsigned long)t->loc, | |
4230 | get_order(sizeof(struct location) * t->max)); | |
4231 | } | |
4232 | ||
68dff6a9 | 4233 | static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) |
88a420e4 CL |
4234 | { |
4235 | struct location *l; | |
4236 | int order; | |
4237 | ||
88a420e4 CL |
4238 | order = get_order(sizeof(struct location) * max); |
4239 | ||
68dff6a9 | 4240 | l = (void *)__get_free_pages(flags, order); |
88a420e4 CL |
4241 | if (!l) |
4242 | return 0; | |
4243 | ||
4244 | if (t->count) { | |
4245 | memcpy(l, t->loc, sizeof(struct location) * t->count); | |
4246 | free_loc_track(t); | |
4247 | } | |
4248 | t->max = max; | |
4249 | t->loc = l; | |
4250 | return 1; | |
4251 | } | |
4252 | ||
4253 | static int add_location(struct loc_track *t, struct kmem_cache *s, | |
45edfa58 | 4254 | const struct track *track) |
88a420e4 CL |
4255 | { |
4256 | long start, end, pos; | |
4257 | struct location *l; | |
ce71e27c | 4258 | unsigned long caddr; |
45edfa58 | 4259 | unsigned long age = jiffies - track->when; |
88a420e4 CL |
4260 | |
4261 | start = -1; | |
4262 | end = t->count; | |
4263 | ||
4264 | for ( ; ; ) { | |
4265 | pos = start + (end - start + 1) / 2; | |
4266 | ||
4267 | /* | |
4268 | * There is nothing at "end". If we end up there | |
4269 | * we need to add something to before end. | |
4270 | */ | |
4271 | if (pos == end) | |
4272 | break; | |
4273 | ||
4274 | caddr = t->loc[pos].addr; | |
45edfa58 CL |
4275 | if (track->addr == caddr) { |
4276 | ||
4277 | l = &t->loc[pos]; | |
4278 | l->count++; | |
4279 | if (track->when) { | |
4280 | l->sum_time += age; | |
4281 | if (age < l->min_time) | |
4282 | l->min_time = age; | |
4283 | if (age > l->max_time) | |
4284 | l->max_time = age; | |
4285 | ||
4286 | if (track->pid < l->min_pid) | |
4287 | l->min_pid = track->pid; | |
4288 | if (track->pid > l->max_pid) | |
4289 | l->max_pid = track->pid; | |
4290 | ||
174596a0 RR |
4291 | cpumask_set_cpu(track->cpu, |
4292 | to_cpumask(l->cpus)); | |
45edfa58 CL |
4293 | } |
4294 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
4295 | return 1; |
4296 | } | |
4297 | ||
45edfa58 | 4298 | if (track->addr < caddr) |
88a420e4 CL |
4299 | end = pos; |
4300 | else | |
4301 | start = pos; | |
4302 | } | |
4303 | ||
4304 | /* | |
672bba3a | 4305 | * Not found. Insert new tracking element. |
88a420e4 | 4306 | */ |
68dff6a9 | 4307 | if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) |
88a420e4 CL |
4308 | return 0; |
4309 | ||
4310 | l = t->loc + pos; | |
4311 | if (pos < t->count) | |
4312 | memmove(l + 1, l, | |
4313 | (t->count - pos) * sizeof(struct location)); | |
4314 | t->count++; | |
4315 | l->count = 1; | |
45edfa58 CL |
4316 | l->addr = track->addr; |
4317 | l->sum_time = age; | |
4318 | l->min_time = age; | |
4319 | l->max_time = age; | |
4320 | l->min_pid = track->pid; | |
4321 | l->max_pid = track->pid; | |
174596a0 RR |
4322 | cpumask_clear(to_cpumask(l->cpus)); |
4323 | cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); | |
45edfa58 CL |
4324 | nodes_clear(l->nodes); |
4325 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
4326 | return 1; |
4327 | } | |
4328 | ||
4329 | static void process_slab(struct loc_track *t, struct kmem_cache *s, | |
bbd7d57b | 4330 | struct page *page, enum track_item alloc, |
a5dd5c11 | 4331 | unsigned long *map) |
88a420e4 | 4332 | { |
a973e9dd | 4333 | void *addr = page_address(page); |
88a420e4 CL |
4334 | void *p; |
4335 | ||
39b26464 | 4336 | bitmap_zero(map, page->objects); |
5f80b13a | 4337 | get_map(s, page, map); |
88a420e4 | 4338 | |
224a88be | 4339 | for_each_object(p, s, addr, page->objects) |
45edfa58 CL |
4340 | if (!test_bit(slab_index(p, s, addr), map)) |
4341 | add_location(t, s, get_track(s, p, alloc)); | |
88a420e4 CL |
4342 | } |
4343 | ||
4344 | static int list_locations(struct kmem_cache *s, char *buf, | |
4345 | enum track_item alloc) | |
4346 | { | |
e374d483 | 4347 | int len = 0; |
88a420e4 | 4348 | unsigned long i; |
68dff6a9 | 4349 | struct loc_track t = { 0, 0, NULL }; |
88a420e4 | 4350 | int node; |
bbd7d57b ED |
4351 | unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) * |
4352 | sizeof(unsigned long), GFP_KERNEL); | |
fa45dc25 | 4353 | struct kmem_cache_node *n; |
88a420e4 | 4354 | |
bbd7d57b ED |
4355 | if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location), |
4356 | GFP_TEMPORARY)) { | |
4357 | kfree(map); | |
68dff6a9 | 4358 | return sprintf(buf, "Out of memory\n"); |
bbd7d57b | 4359 | } |
88a420e4 CL |
4360 | /* Push back cpu slabs */ |
4361 | flush_all(s); | |
4362 | ||
fa45dc25 | 4363 | for_each_kmem_cache_node(s, node, n) { |
88a420e4 CL |
4364 | unsigned long flags; |
4365 | struct page *page; | |
4366 | ||
9e86943b | 4367 | if (!atomic_long_read(&n->nr_slabs)) |
88a420e4 CL |
4368 | continue; |
4369 | ||
4370 | spin_lock_irqsave(&n->list_lock, flags); | |
4371 | list_for_each_entry(page, &n->partial, lru) | |
bbd7d57b | 4372 | process_slab(&t, s, page, alloc, map); |
88a420e4 | 4373 | list_for_each_entry(page, &n->full, lru) |
bbd7d57b | 4374 | process_slab(&t, s, page, alloc, map); |
88a420e4 CL |
4375 | spin_unlock_irqrestore(&n->list_lock, flags); |
4376 | } | |
4377 | ||
4378 | for (i = 0; i < t.count; i++) { | |
45edfa58 | 4379 | struct location *l = &t.loc[i]; |
88a420e4 | 4380 | |
9c246247 | 4381 | if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100) |
88a420e4 | 4382 | break; |
e374d483 | 4383 | len += sprintf(buf + len, "%7ld ", l->count); |
45edfa58 CL |
4384 | |
4385 | if (l->addr) | |
62c70bce | 4386 | len += sprintf(buf + len, "%pS", (void *)l->addr); |
88a420e4 | 4387 | else |
e374d483 | 4388 | len += sprintf(buf + len, "<not-available>"); |
45edfa58 CL |
4389 | |
4390 | if (l->sum_time != l->min_time) { | |
e374d483 | 4391 | len += sprintf(buf + len, " age=%ld/%ld/%ld", |
f8bd2258 RZ |
4392 | l->min_time, |
4393 | (long)div_u64(l->sum_time, l->count), | |
4394 | l->max_time); | |
45edfa58 | 4395 | } else |
e374d483 | 4396 | len += sprintf(buf + len, " age=%ld", |
45edfa58 CL |
4397 | l->min_time); |
4398 | ||
4399 | if (l->min_pid != l->max_pid) | |
e374d483 | 4400 | len += sprintf(buf + len, " pid=%ld-%ld", |
45edfa58 CL |
4401 | l->min_pid, l->max_pid); |
4402 | else | |
e374d483 | 4403 | len += sprintf(buf + len, " pid=%ld", |
45edfa58 CL |
4404 | l->min_pid); |
4405 | ||
174596a0 RR |
4406 | if (num_online_cpus() > 1 && |
4407 | !cpumask_empty(to_cpumask(l->cpus)) && | |
5024c1d7 TH |
4408 | len < PAGE_SIZE - 60) |
4409 | len += scnprintf(buf + len, PAGE_SIZE - len - 50, | |
4410 | " cpus=%*pbl", | |
4411 | cpumask_pr_args(to_cpumask(l->cpus))); | |
45edfa58 | 4412 | |
62bc62a8 | 4413 | if (nr_online_nodes > 1 && !nodes_empty(l->nodes) && |
5024c1d7 TH |
4414 | len < PAGE_SIZE - 60) |
4415 | len += scnprintf(buf + len, PAGE_SIZE - len - 50, | |
4416 | " nodes=%*pbl", | |
4417 | nodemask_pr_args(&l->nodes)); | |
45edfa58 | 4418 | |
e374d483 | 4419 | len += sprintf(buf + len, "\n"); |
88a420e4 CL |
4420 | } |
4421 | ||
4422 | free_loc_track(&t); | |
bbd7d57b | 4423 | kfree(map); |
88a420e4 | 4424 | if (!t.count) |
e374d483 HH |
4425 | len += sprintf(buf, "No data\n"); |
4426 | return len; | |
88a420e4 | 4427 | } |
ab4d5ed5 | 4428 | #endif |
88a420e4 | 4429 | |
a5a84755 | 4430 | #ifdef SLUB_RESILIENCY_TEST |
c07b8183 | 4431 | static void __init resiliency_test(void) |
a5a84755 CL |
4432 | { |
4433 | u8 *p; | |
4434 | ||
95a05b42 | 4435 | BUILD_BUG_ON(KMALLOC_MIN_SIZE > 16 || KMALLOC_SHIFT_HIGH < 10); |
a5a84755 | 4436 | |
f9f58285 FF |
4437 | pr_err("SLUB resiliency testing\n"); |
4438 | pr_err("-----------------------\n"); | |
4439 | pr_err("A. Corruption after allocation\n"); | |
a5a84755 CL |
4440 | |
4441 | p = kzalloc(16, GFP_KERNEL); | |
4442 | p[16] = 0x12; | |
f9f58285 FF |
4443 | pr_err("\n1. kmalloc-16: Clobber Redzone/next pointer 0x12->0x%p\n\n", |
4444 | p + 16); | |
a5a84755 CL |
4445 | |
4446 | validate_slab_cache(kmalloc_caches[4]); | |
4447 | ||
4448 | /* Hmmm... The next two are dangerous */ | |
4449 | p = kzalloc(32, GFP_KERNEL); | |
4450 | p[32 + sizeof(void *)] = 0x34; | |
f9f58285 FF |
4451 | pr_err("\n2. kmalloc-32: Clobber next pointer/next slab 0x34 -> -0x%p\n", |
4452 | p); | |
4453 | pr_err("If allocated object is overwritten then not detectable\n\n"); | |
a5a84755 CL |
4454 | |
4455 | validate_slab_cache(kmalloc_caches[5]); | |
4456 | p = kzalloc(64, GFP_KERNEL); | |
4457 | p += 64 + (get_cycles() & 0xff) * sizeof(void *); | |
4458 | *p = 0x56; | |
f9f58285 FF |
4459 | pr_err("\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n", |
4460 | p); | |
4461 | pr_err("If allocated object is overwritten then not detectable\n\n"); | |
a5a84755 CL |
4462 | validate_slab_cache(kmalloc_caches[6]); |
4463 | ||
f9f58285 | 4464 | pr_err("\nB. Corruption after free\n"); |
a5a84755 CL |
4465 | p = kzalloc(128, GFP_KERNEL); |
4466 | kfree(p); | |
4467 | *p = 0x78; | |
f9f58285 | 4468 | pr_err("1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p); |
a5a84755 CL |
4469 | validate_slab_cache(kmalloc_caches[7]); |
4470 | ||
4471 | p = kzalloc(256, GFP_KERNEL); | |
4472 | kfree(p); | |
4473 | p[50] = 0x9a; | |
f9f58285 | 4474 | pr_err("\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p); |
a5a84755 CL |
4475 | validate_slab_cache(kmalloc_caches[8]); |
4476 | ||
4477 | p = kzalloc(512, GFP_KERNEL); | |
4478 | kfree(p); | |
4479 | p[512] = 0xab; | |
f9f58285 | 4480 | pr_err("\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p); |
a5a84755 CL |
4481 | validate_slab_cache(kmalloc_caches[9]); |
4482 | } | |
4483 | #else | |
4484 | #ifdef CONFIG_SYSFS | |
4485 | static void resiliency_test(void) {}; | |
4486 | #endif | |
4487 | #endif | |
4488 | ||
ab4d5ed5 | 4489 | #ifdef CONFIG_SYSFS |
81819f0f | 4490 | enum slab_stat_type { |
205ab99d CL |
4491 | SL_ALL, /* All slabs */ |
4492 | SL_PARTIAL, /* Only partially allocated slabs */ | |
4493 | SL_CPU, /* Only slabs used for cpu caches */ | |
4494 | SL_OBJECTS, /* Determine allocated objects not slabs */ | |
4495 | SL_TOTAL /* Determine object capacity not slabs */ | |
81819f0f CL |
4496 | }; |
4497 | ||
205ab99d | 4498 | #define SO_ALL (1 << SL_ALL) |
81819f0f CL |
4499 | #define SO_PARTIAL (1 << SL_PARTIAL) |
4500 | #define SO_CPU (1 << SL_CPU) | |
4501 | #define SO_OBJECTS (1 << SL_OBJECTS) | |
205ab99d | 4502 | #define SO_TOTAL (1 << SL_TOTAL) |
81819f0f | 4503 | |
62e5c4b4 CG |
4504 | static ssize_t show_slab_objects(struct kmem_cache *s, |
4505 | char *buf, unsigned long flags) | |
81819f0f CL |
4506 | { |
4507 | unsigned long total = 0; | |
81819f0f CL |
4508 | int node; |
4509 | int x; | |
4510 | unsigned long *nodes; | |
81819f0f | 4511 | |
e35e1a97 | 4512 | nodes = kzalloc(sizeof(unsigned long) * nr_node_ids, GFP_KERNEL); |
62e5c4b4 CG |
4513 | if (!nodes) |
4514 | return -ENOMEM; | |
81819f0f | 4515 | |
205ab99d CL |
4516 | if (flags & SO_CPU) { |
4517 | int cpu; | |
81819f0f | 4518 | |
205ab99d | 4519 | for_each_possible_cpu(cpu) { |
d0e0ac97 CG |
4520 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, |
4521 | cpu); | |
ec3ab083 | 4522 | int node; |
49e22585 | 4523 | struct page *page; |
dfb4f096 | 4524 | |
4db0c3c2 | 4525 | page = READ_ONCE(c->page); |
ec3ab083 CL |
4526 | if (!page) |
4527 | continue; | |
205ab99d | 4528 | |
ec3ab083 CL |
4529 | node = page_to_nid(page); |
4530 | if (flags & SO_TOTAL) | |
4531 | x = page->objects; | |
4532 | else if (flags & SO_OBJECTS) | |
4533 | x = page->inuse; | |
4534 | else | |
4535 | x = 1; | |
49e22585 | 4536 | |
ec3ab083 CL |
4537 | total += x; |
4538 | nodes[node] += x; | |
4539 | ||
4db0c3c2 | 4540 | page = READ_ONCE(c->partial); |
49e22585 | 4541 | if (page) { |
8afb1474 LZ |
4542 | node = page_to_nid(page); |
4543 | if (flags & SO_TOTAL) | |
4544 | WARN_ON_ONCE(1); | |
4545 | else if (flags & SO_OBJECTS) | |
4546 | WARN_ON_ONCE(1); | |
4547 | else | |
4548 | x = page->pages; | |
bc6697d8 ED |
4549 | total += x; |
4550 | nodes[node] += x; | |
49e22585 | 4551 | } |
81819f0f CL |
4552 | } |
4553 | } | |
4554 | ||
bfc8c901 | 4555 | get_online_mems(); |
ab4d5ed5 | 4556 | #ifdef CONFIG_SLUB_DEBUG |
205ab99d | 4557 | if (flags & SO_ALL) { |
fa45dc25 CL |
4558 | struct kmem_cache_node *n; |
4559 | ||
4560 | for_each_kmem_cache_node(s, node, n) { | |
205ab99d | 4561 | |
d0e0ac97 CG |
4562 | if (flags & SO_TOTAL) |
4563 | x = atomic_long_read(&n->total_objects); | |
4564 | else if (flags & SO_OBJECTS) | |
4565 | x = atomic_long_read(&n->total_objects) - | |
4566 | count_partial(n, count_free); | |
81819f0f | 4567 | else |
205ab99d | 4568 | x = atomic_long_read(&n->nr_slabs); |
81819f0f CL |
4569 | total += x; |
4570 | nodes[node] += x; | |
4571 | } | |
4572 | ||
ab4d5ed5 CL |
4573 | } else |
4574 | #endif | |
4575 | if (flags & SO_PARTIAL) { | |
fa45dc25 | 4576 | struct kmem_cache_node *n; |
81819f0f | 4577 | |
fa45dc25 | 4578 | for_each_kmem_cache_node(s, node, n) { |
205ab99d CL |
4579 | if (flags & SO_TOTAL) |
4580 | x = count_partial(n, count_total); | |
4581 | else if (flags & SO_OBJECTS) | |
4582 | x = count_partial(n, count_inuse); | |
81819f0f | 4583 | else |
205ab99d | 4584 | x = n->nr_partial; |
81819f0f CL |
4585 | total += x; |
4586 | nodes[node] += x; | |
4587 | } | |
4588 | } | |
81819f0f CL |
4589 | x = sprintf(buf, "%lu", total); |
4590 | #ifdef CONFIG_NUMA | |
fa45dc25 | 4591 | for (node = 0; node < nr_node_ids; node++) |
81819f0f CL |
4592 | if (nodes[node]) |
4593 | x += sprintf(buf + x, " N%d=%lu", | |
4594 | node, nodes[node]); | |
4595 | #endif | |
bfc8c901 | 4596 | put_online_mems(); |
81819f0f CL |
4597 | kfree(nodes); |
4598 | return x + sprintf(buf + x, "\n"); | |
4599 | } | |
4600 | ||
ab4d5ed5 | 4601 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
4602 | static int any_slab_objects(struct kmem_cache *s) |
4603 | { | |
4604 | int node; | |
fa45dc25 | 4605 | struct kmem_cache_node *n; |
81819f0f | 4606 | |
fa45dc25 | 4607 | for_each_kmem_cache_node(s, node, n) |
4ea33e2d | 4608 | if (atomic_long_read(&n->total_objects)) |
81819f0f | 4609 | return 1; |
fa45dc25 | 4610 | |
81819f0f CL |
4611 | return 0; |
4612 | } | |
ab4d5ed5 | 4613 | #endif |
81819f0f CL |
4614 | |
4615 | #define to_slab_attr(n) container_of(n, struct slab_attribute, attr) | |
497888cf | 4616 | #define to_slab(n) container_of(n, struct kmem_cache, kobj) |
81819f0f CL |
4617 | |
4618 | struct slab_attribute { | |
4619 | struct attribute attr; | |
4620 | ssize_t (*show)(struct kmem_cache *s, char *buf); | |
4621 | ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); | |
4622 | }; | |
4623 | ||
4624 | #define SLAB_ATTR_RO(_name) \ | |
ab067e99 VK |
4625 | static struct slab_attribute _name##_attr = \ |
4626 | __ATTR(_name, 0400, _name##_show, NULL) | |
81819f0f CL |
4627 | |
4628 | #define SLAB_ATTR(_name) \ | |
4629 | static struct slab_attribute _name##_attr = \ | |
ab067e99 | 4630 | __ATTR(_name, 0600, _name##_show, _name##_store) |
81819f0f | 4631 | |
81819f0f CL |
4632 | static ssize_t slab_size_show(struct kmem_cache *s, char *buf) |
4633 | { | |
4634 | return sprintf(buf, "%d\n", s->size); | |
4635 | } | |
4636 | SLAB_ATTR_RO(slab_size); | |
4637 | ||
4638 | static ssize_t align_show(struct kmem_cache *s, char *buf) | |
4639 | { | |
4640 | return sprintf(buf, "%d\n", s->align); | |
4641 | } | |
4642 | SLAB_ATTR_RO(align); | |
4643 | ||
4644 | static ssize_t object_size_show(struct kmem_cache *s, char *buf) | |
4645 | { | |
3b0efdfa | 4646 | return sprintf(buf, "%d\n", s->object_size); |
81819f0f CL |
4647 | } |
4648 | SLAB_ATTR_RO(object_size); | |
4649 | ||
4650 | static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) | |
4651 | { | |
834f3d11 | 4652 | return sprintf(buf, "%d\n", oo_objects(s->oo)); |
81819f0f CL |
4653 | } |
4654 | SLAB_ATTR_RO(objs_per_slab); | |
4655 | ||
06b285dc CL |
4656 | static ssize_t order_store(struct kmem_cache *s, |
4657 | const char *buf, size_t length) | |
4658 | { | |
0121c619 CL |
4659 | unsigned long order; |
4660 | int err; | |
4661 | ||
3dbb95f7 | 4662 | err = kstrtoul(buf, 10, &order); |
0121c619 CL |
4663 | if (err) |
4664 | return err; | |
06b285dc CL |
4665 | |
4666 | if (order > slub_max_order || order < slub_min_order) | |
4667 | return -EINVAL; | |
4668 | ||
4669 | calculate_sizes(s, order); | |
4670 | return length; | |
4671 | } | |
4672 | ||
81819f0f CL |
4673 | static ssize_t order_show(struct kmem_cache *s, char *buf) |
4674 | { | |
834f3d11 | 4675 | return sprintf(buf, "%d\n", oo_order(s->oo)); |
81819f0f | 4676 | } |
06b285dc | 4677 | SLAB_ATTR(order); |
81819f0f | 4678 | |
73d342b1 DR |
4679 | static ssize_t min_partial_show(struct kmem_cache *s, char *buf) |
4680 | { | |
4681 | return sprintf(buf, "%lu\n", s->min_partial); | |
4682 | } | |
4683 | ||
4684 | static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, | |
4685 | size_t length) | |
4686 | { | |
4687 | unsigned long min; | |
4688 | int err; | |
4689 | ||
3dbb95f7 | 4690 | err = kstrtoul(buf, 10, &min); |
73d342b1 DR |
4691 | if (err) |
4692 | return err; | |
4693 | ||
c0bdb232 | 4694 | set_min_partial(s, min); |
73d342b1 DR |
4695 | return length; |
4696 | } | |
4697 | SLAB_ATTR(min_partial); | |
4698 | ||
49e22585 CL |
4699 | static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) |
4700 | { | |
4701 | return sprintf(buf, "%u\n", s->cpu_partial); | |
4702 | } | |
4703 | ||
4704 | static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, | |
4705 | size_t length) | |
4706 | { | |
4707 | unsigned long objects; | |
4708 | int err; | |
4709 | ||
3dbb95f7 | 4710 | err = kstrtoul(buf, 10, &objects); |
49e22585 CL |
4711 | if (err) |
4712 | return err; | |
345c905d | 4713 | if (objects && !kmem_cache_has_cpu_partial(s)) |
74ee4ef1 | 4714 | return -EINVAL; |
49e22585 CL |
4715 | |
4716 | s->cpu_partial = objects; | |
4717 | flush_all(s); | |
4718 | return length; | |
4719 | } | |
4720 | SLAB_ATTR(cpu_partial); | |
4721 | ||
81819f0f CL |
4722 | static ssize_t ctor_show(struct kmem_cache *s, char *buf) |
4723 | { | |
62c70bce JP |
4724 | if (!s->ctor) |
4725 | return 0; | |
4726 | return sprintf(buf, "%pS\n", s->ctor); | |
81819f0f CL |
4727 | } |
4728 | SLAB_ATTR_RO(ctor); | |
4729 | ||
81819f0f CL |
4730 | static ssize_t aliases_show(struct kmem_cache *s, char *buf) |
4731 | { | |
4307c14f | 4732 | return sprintf(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); |
81819f0f CL |
4733 | } |
4734 | SLAB_ATTR_RO(aliases); | |
4735 | ||
81819f0f CL |
4736 | static ssize_t partial_show(struct kmem_cache *s, char *buf) |
4737 | { | |
d9acf4b7 | 4738 | return show_slab_objects(s, buf, SO_PARTIAL); |
81819f0f CL |
4739 | } |
4740 | SLAB_ATTR_RO(partial); | |
4741 | ||
4742 | static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) | |
4743 | { | |
d9acf4b7 | 4744 | return show_slab_objects(s, buf, SO_CPU); |
81819f0f CL |
4745 | } |
4746 | SLAB_ATTR_RO(cpu_slabs); | |
4747 | ||
4748 | static ssize_t objects_show(struct kmem_cache *s, char *buf) | |
4749 | { | |
205ab99d | 4750 | return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); |
81819f0f CL |
4751 | } |
4752 | SLAB_ATTR_RO(objects); | |
4753 | ||
205ab99d CL |
4754 | static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) |
4755 | { | |
4756 | return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); | |
4757 | } | |
4758 | SLAB_ATTR_RO(objects_partial); | |
4759 | ||
49e22585 CL |
4760 | static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) |
4761 | { | |
4762 | int objects = 0; | |
4763 | int pages = 0; | |
4764 | int cpu; | |
4765 | int len; | |
4766 | ||
4767 | for_each_online_cpu(cpu) { | |
4768 | struct page *page = per_cpu_ptr(s->cpu_slab, cpu)->partial; | |
4769 | ||
4770 | if (page) { | |
4771 | pages += page->pages; | |
4772 | objects += page->pobjects; | |
4773 | } | |
4774 | } | |
4775 | ||
4776 | len = sprintf(buf, "%d(%d)", objects, pages); | |
4777 | ||
4778 | #ifdef CONFIG_SMP | |
4779 | for_each_online_cpu(cpu) { | |
4780 | struct page *page = per_cpu_ptr(s->cpu_slab, cpu) ->partial; | |
4781 | ||
4782 | if (page && len < PAGE_SIZE - 20) | |
4783 | len += sprintf(buf + len, " C%d=%d(%d)", cpu, | |
4784 | page->pobjects, page->pages); | |
4785 | } | |
4786 | #endif | |
4787 | return len + sprintf(buf + len, "\n"); | |
4788 | } | |
4789 | SLAB_ATTR_RO(slabs_cpu_partial); | |
4790 | ||
a5a84755 CL |
4791 | static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) |
4792 | { | |
4793 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); | |
4794 | } | |
4795 | ||
4796 | static ssize_t reclaim_account_store(struct kmem_cache *s, | |
4797 | const char *buf, size_t length) | |
4798 | { | |
4799 | s->flags &= ~SLAB_RECLAIM_ACCOUNT; | |
4800 | if (buf[0] == '1') | |
4801 | s->flags |= SLAB_RECLAIM_ACCOUNT; | |
4802 | return length; | |
4803 | } | |
4804 | SLAB_ATTR(reclaim_account); | |
4805 | ||
4806 | static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) | |
4807 | { | |
4808 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); | |
4809 | } | |
4810 | SLAB_ATTR_RO(hwcache_align); | |
4811 | ||
4812 | #ifdef CONFIG_ZONE_DMA | |
4813 | static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) | |
4814 | { | |
4815 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); | |
4816 | } | |
4817 | SLAB_ATTR_RO(cache_dma); | |
4818 | #endif | |
4819 | ||
4820 | static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) | |
4821 | { | |
4822 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU)); | |
4823 | } | |
4824 | SLAB_ATTR_RO(destroy_by_rcu); | |
4825 | ||
ab9a0f19 LJ |
4826 | static ssize_t reserved_show(struct kmem_cache *s, char *buf) |
4827 | { | |
4828 | return sprintf(buf, "%d\n", s->reserved); | |
4829 | } | |
4830 | SLAB_ATTR_RO(reserved); | |
4831 | ||
ab4d5ed5 | 4832 | #ifdef CONFIG_SLUB_DEBUG |
a5a84755 CL |
4833 | static ssize_t slabs_show(struct kmem_cache *s, char *buf) |
4834 | { | |
4835 | return show_slab_objects(s, buf, SO_ALL); | |
4836 | } | |
4837 | SLAB_ATTR_RO(slabs); | |
4838 | ||
205ab99d CL |
4839 | static ssize_t total_objects_show(struct kmem_cache *s, char *buf) |
4840 | { | |
4841 | return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); | |
4842 | } | |
4843 | SLAB_ATTR_RO(total_objects); | |
4844 | ||
81819f0f CL |
4845 | static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) |
4846 | { | |
becfda68 | 4847 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); |
81819f0f CL |
4848 | } |
4849 | ||
4850 | static ssize_t sanity_checks_store(struct kmem_cache *s, | |
4851 | const char *buf, size_t length) | |
4852 | { | |
becfda68 | 4853 | s->flags &= ~SLAB_CONSISTENCY_CHECKS; |
b789ef51 CL |
4854 | if (buf[0] == '1') { |
4855 | s->flags &= ~__CMPXCHG_DOUBLE; | |
becfda68 | 4856 | s->flags |= SLAB_CONSISTENCY_CHECKS; |
b789ef51 | 4857 | } |
81819f0f CL |
4858 | return length; |
4859 | } | |
4860 | SLAB_ATTR(sanity_checks); | |
4861 | ||
4862 | static ssize_t trace_show(struct kmem_cache *s, char *buf) | |
4863 | { | |
4864 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE)); | |
4865 | } | |
4866 | ||
4867 | static ssize_t trace_store(struct kmem_cache *s, const char *buf, | |
4868 | size_t length) | |
4869 | { | |
c9e16131 CL |
4870 | /* |
4871 | * Tracing a merged cache is going to give confusing results | |
4872 | * as well as cause other issues like converting a mergeable | |
4873 | * cache into an umergeable one. | |
4874 | */ | |
4875 | if (s->refcount > 1) | |
4876 | return -EINVAL; | |
4877 | ||
81819f0f | 4878 | s->flags &= ~SLAB_TRACE; |
b789ef51 CL |
4879 | if (buf[0] == '1') { |
4880 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4881 | s->flags |= SLAB_TRACE; |
b789ef51 | 4882 | } |
81819f0f CL |
4883 | return length; |
4884 | } | |
4885 | SLAB_ATTR(trace); | |
4886 | ||
81819f0f CL |
4887 | static ssize_t red_zone_show(struct kmem_cache *s, char *buf) |
4888 | { | |
4889 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); | |
4890 | } | |
4891 | ||
4892 | static ssize_t red_zone_store(struct kmem_cache *s, | |
4893 | const char *buf, size_t length) | |
4894 | { | |
4895 | if (any_slab_objects(s)) | |
4896 | return -EBUSY; | |
4897 | ||
4898 | s->flags &= ~SLAB_RED_ZONE; | |
b789ef51 | 4899 | if (buf[0] == '1') { |
81819f0f | 4900 | s->flags |= SLAB_RED_ZONE; |
b789ef51 | 4901 | } |
06b285dc | 4902 | calculate_sizes(s, -1); |
81819f0f CL |
4903 | return length; |
4904 | } | |
4905 | SLAB_ATTR(red_zone); | |
4906 | ||
4907 | static ssize_t poison_show(struct kmem_cache *s, char *buf) | |
4908 | { | |
4909 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON)); | |
4910 | } | |
4911 | ||
4912 | static ssize_t poison_store(struct kmem_cache *s, | |
4913 | const char *buf, size_t length) | |
4914 | { | |
4915 | if (any_slab_objects(s)) | |
4916 | return -EBUSY; | |
4917 | ||
4918 | s->flags &= ~SLAB_POISON; | |
b789ef51 | 4919 | if (buf[0] == '1') { |
81819f0f | 4920 | s->flags |= SLAB_POISON; |
b789ef51 | 4921 | } |
06b285dc | 4922 | calculate_sizes(s, -1); |
81819f0f CL |
4923 | return length; |
4924 | } | |
4925 | SLAB_ATTR(poison); | |
4926 | ||
4927 | static ssize_t store_user_show(struct kmem_cache *s, char *buf) | |
4928 | { | |
4929 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); | |
4930 | } | |
4931 | ||
4932 | static ssize_t store_user_store(struct kmem_cache *s, | |
4933 | const char *buf, size_t length) | |
4934 | { | |
4935 | if (any_slab_objects(s)) | |
4936 | return -EBUSY; | |
4937 | ||
4938 | s->flags &= ~SLAB_STORE_USER; | |
b789ef51 CL |
4939 | if (buf[0] == '1') { |
4940 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4941 | s->flags |= SLAB_STORE_USER; |
b789ef51 | 4942 | } |
06b285dc | 4943 | calculate_sizes(s, -1); |
81819f0f CL |
4944 | return length; |
4945 | } | |
4946 | SLAB_ATTR(store_user); | |
4947 | ||
53e15af0 CL |
4948 | static ssize_t validate_show(struct kmem_cache *s, char *buf) |
4949 | { | |
4950 | return 0; | |
4951 | } | |
4952 | ||
4953 | static ssize_t validate_store(struct kmem_cache *s, | |
4954 | const char *buf, size_t length) | |
4955 | { | |
434e245d CL |
4956 | int ret = -EINVAL; |
4957 | ||
4958 | if (buf[0] == '1') { | |
4959 | ret = validate_slab_cache(s); | |
4960 | if (ret >= 0) | |
4961 | ret = length; | |
4962 | } | |
4963 | return ret; | |
53e15af0 CL |
4964 | } |
4965 | SLAB_ATTR(validate); | |
a5a84755 CL |
4966 | |
4967 | static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf) | |
4968 | { | |
4969 | if (!(s->flags & SLAB_STORE_USER)) | |
4970 | return -ENOSYS; | |
4971 | return list_locations(s, buf, TRACK_ALLOC); | |
4972 | } | |
4973 | SLAB_ATTR_RO(alloc_calls); | |
4974 | ||
4975 | static ssize_t free_calls_show(struct kmem_cache *s, char *buf) | |
4976 | { | |
4977 | if (!(s->flags & SLAB_STORE_USER)) | |
4978 | return -ENOSYS; | |
4979 | return list_locations(s, buf, TRACK_FREE); | |
4980 | } | |
4981 | SLAB_ATTR_RO(free_calls); | |
4982 | #endif /* CONFIG_SLUB_DEBUG */ | |
4983 | ||
4984 | #ifdef CONFIG_FAILSLAB | |
4985 | static ssize_t failslab_show(struct kmem_cache *s, char *buf) | |
4986 | { | |
4987 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); | |
4988 | } | |
4989 | ||
4990 | static ssize_t failslab_store(struct kmem_cache *s, const char *buf, | |
4991 | size_t length) | |
4992 | { | |
c9e16131 CL |
4993 | if (s->refcount > 1) |
4994 | return -EINVAL; | |
4995 | ||
a5a84755 CL |
4996 | s->flags &= ~SLAB_FAILSLAB; |
4997 | if (buf[0] == '1') | |
4998 | s->flags |= SLAB_FAILSLAB; | |
4999 | return length; | |
5000 | } | |
5001 | SLAB_ATTR(failslab); | |
ab4d5ed5 | 5002 | #endif |
53e15af0 | 5003 | |
2086d26a CL |
5004 | static ssize_t shrink_show(struct kmem_cache *s, char *buf) |
5005 | { | |
5006 | return 0; | |
5007 | } | |
5008 | ||
5009 | static ssize_t shrink_store(struct kmem_cache *s, | |
5010 | const char *buf, size_t length) | |
5011 | { | |
832f37f5 VD |
5012 | if (buf[0] == '1') |
5013 | kmem_cache_shrink(s); | |
5014 | else | |
2086d26a CL |
5015 | return -EINVAL; |
5016 | return length; | |
5017 | } | |
5018 | SLAB_ATTR(shrink); | |
5019 | ||
81819f0f | 5020 | #ifdef CONFIG_NUMA |
9824601e | 5021 | static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) |
81819f0f | 5022 | { |
9824601e | 5023 | return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10); |
81819f0f CL |
5024 | } |
5025 | ||
9824601e | 5026 | static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, |
81819f0f CL |
5027 | const char *buf, size_t length) |
5028 | { | |
0121c619 CL |
5029 | unsigned long ratio; |
5030 | int err; | |
5031 | ||
3dbb95f7 | 5032 | err = kstrtoul(buf, 10, &ratio); |
0121c619 CL |
5033 | if (err) |
5034 | return err; | |
5035 | ||
e2cb96b7 | 5036 | if (ratio <= 100) |
0121c619 | 5037 | s->remote_node_defrag_ratio = ratio * 10; |
81819f0f | 5038 | |
81819f0f CL |
5039 | return length; |
5040 | } | |
9824601e | 5041 | SLAB_ATTR(remote_node_defrag_ratio); |
81819f0f CL |
5042 | #endif |
5043 | ||
8ff12cfc | 5044 | #ifdef CONFIG_SLUB_STATS |
8ff12cfc CL |
5045 | static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) |
5046 | { | |
5047 | unsigned long sum = 0; | |
5048 | int cpu; | |
5049 | int len; | |
5050 | int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); | |
5051 | ||
5052 | if (!data) | |
5053 | return -ENOMEM; | |
5054 | ||
5055 | for_each_online_cpu(cpu) { | |
9dfc6e68 | 5056 | unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; |
8ff12cfc CL |
5057 | |
5058 | data[cpu] = x; | |
5059 | sum += x; | |
5060 | } | |
5061 | ||
5062 | len = sprintf(buf, "%lu", sum); | |
5063 | ||
50ef37b9 | 5064 | #ifdef CONFIG_SMP |
8ff12cfc CL |
5065 | for_each_online_cpu(cpu) { |
5066 | if (data[cpu] && len < PAGE_SIZE - 20) | |
50ef37b9 | 5067 | len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]); |
8ff12cfc | 5068 | } |
50ef37b9 | 5069 | #endif |
8ff12cfc CL |
5070 | kfree(data); |
5071 | return len + sprintf(buf + len, "\n"); | |
5072 | } | |
5073 | ||
78eb00cc DR |
5074 | static void clear_stat(struct kmem_cache *s, enum stat_item si) |
5075 | { | |
5076 | int cpu; | |
5077 | ||
5078 | for_each_online_cpu(cpu) | |
9dfc6e68 | 5079 | per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; |
78eb00cc DR |
5080 | } |
5081 | ||
8ff12cfc CL |
5082 | #define STAT_ATTR(si, text) \ |
5083 | static ssize_t text##_show(struct kmem_cache *s, char *buf) \ | |
5084 | { \ | |
5085 | return show_stat(s, buf, si); \ | |
5086 | } \ | |
78eb00cc DR |
5087 | static ssize_t text##_store(struct kmem_cache *s, \ |
5088 | const char *buf, size_t length) \ | |
5089 | { \ | |
5090 | if (buf[0] != '0') \ | |
5091 | return -EINVAL; \ | |
5092 | clear_stat(s, si); \ | |
5093 | return length; \ | |
5094 | } \ | |
5095 | SLAB_ATTR(text); \ | |
8ff12cfc CL |
5096 | |
5097 | STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); | |
5098 | STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); | |
5099 | STAT_ATTR(FREE_FASTPATH, free_fastpath); | |
5100 | STAT_ATTR(FREE_SLOWPATH, free_slowpath); | |
5101 | STAT_ATTR(FREE_FROZEN, free_frozen); | |
5102 | STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); | |
5103 | STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); | |
5104 | STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); | |
5105 | STAT_ATTR(ALLOC_SLAB, alloc_slab); | |
5106 | STAT_ATTR(ALLOC_REFILL, alloc_refill); | |
e36a2652 | 5107 | STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); |
8ff12cfc CL |
5108 | STAT_ATTR(FREE_SLAB, free_slab); |
5109 | STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); | |
5110 | STAT_ATTR(DEACTIVATE_FULL, deactivate_full); | |
5111 | STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); | |
5112 | STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); | |
5113 | STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); | |
5114 | STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); | |
03e404af | 5115 | STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); |
65c3376a | 5116 | STAT_ATTR(ORDER_FALLBACK, order_fallback); |
b789ef51 CL |
5117 | STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); |
5118 | STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); | |
49e22585 CL |
5119 | STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); |
5120 | STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); | |
8028dcea AS |
5121 | STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); |
5122 | STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); | |
8ff12cfc CL |
5123 | #endif |
5124 | ||
06428780 | 5125 | static struct attribute *slab_attrs[] = { |
81819f0f CL |
5126 | &slab_size_attr.attr, |
5127 | &object_size_attr.attr, | |
5128 | &objs_per_slab_attr.attr, | |
5129 | &order_attr.attr, | |
73d342b1 | 5130 | &min_partial_attr.attr, |
49e22585 | 5131 | &cpu_partial_attr.attr, |
81819f0f | 5132 | &objects_attr.attr, |
205ab99d | 5133 | &objects_partial_attr.attr, |
81819f0f CL |
5134 | &partial_attr.attr, |
5135 | &cpu_slabs_attr.attr, | |
5136 | &ctor_attr.attr, | |
81819f0f CL |
5137 | &aliases_attr.attr, |
5138 | &align_attr.attr, | |
81819f0f CL |
5139 | &hwcache_align_attr.attr, |
5140 | &reclaim_account_attr.attr, | |
5141 | &destroy_by_rcu_attr.attr, | |
a5a84755 | 5142 | &shrink_attr.attr, |
ab9a0f19 | 5143 | &reserved_attr.attr, |
49e22585 | 5144 | &slabs_cpu_partial_attr.attr, |
ab4d5ed5 | 5145 | #ifdef CONFIG_SLUB_DEBUG |
a5a84755 CL |
5146 | &total_objects_attr.attr, |
5147 | &slabs_attr.attr, | |
5148 | &sanity_checks_attr.attr, | |
5149 | &trace_attr.attr, | |
81819f0f CL |
5150 | &red_zone_attr.attr, |
5151 | &poison_attr.attr, | |
5152 | &store_user_attr.attr, | |
53e15af0 | 5153 | &validate_attr.attr, |
88a420e4 CL |
5154 | &alloc_calls_attr.attr, |
5155 | &free_calls_attr.attr, | |
ab4d5ed5 | 5156 | #endif |
81819f0f CL |
5157 | #ifdef CONFIG_ZONE_DMA |
5158 | &cache_dma_attr.attr, | |
5159 | #endif | |
5160 | #ifdef CONFIG_NUMA | |
9824601e | 5161 | &remote_node_defrag_ratio_attr.attr, |
8ff12cfc CL |
5162 | #endif |
5163 | #ifdef CONFIG_SLUB_STATS | |
5164 | &alloc_fastpath_attr.attr, | |
5165 | &alloc_slowpath_attr.attr, | |
5166 | &free_fastpath_attr.attr, | |
5167 | &free_slowpath_attr.attr, | |
5168 | &free_frozen_attr.attr, | |
5169 | &free_add_partial_attr.attr, | |
5170 | &free_remove_partial_attr.attr, | |
5171 | &alloc_from_partial_attr.attr, | |
5172 | &alloc_slab_attr.attr, | |
5173 | &alloc_refill_attr.attr, | |
e36a2652 | 5174 | &alloc_node_mismatch_attr.attr, |
8ff12cfc CL |
5175 | &free_slab_attr.attr, |
5176 | &cpuslab_flush_attr.attr, | |
5177 | &deactivate_full_attr.attr, | |
5178 | &deactivate_empty_attr.attr, | |
5179 | &deactivate_to_head_attr.attr, | |
5180 | &deactivate_to_tail_attr.attr, | |
5181 | &deactivate_remote_frees_attr.attr, | |
03e404af | 5182 | &deactivate_bypass_attr.attr, |
65c3376a | 5183 | &order_fallback_attr.attr, |
b789ef51 CL |
5184 | &cmpxchg_double_fail_attr.attr, |
5185 | &cmpxchg_double_cpu_fail_attr.attr, | |
49e22585 CL |
5186 | &cpu_partial_alloc_attr.attr, |
5187 | &cpu_partial_free_attr.attr, | |
8028dcea AS |
5188 | &cpu_partial_node_attr.attr, |
5189 | &cpu_partial_drain_attr.attr, | |
81819f0f | 5190 | #endif |
4c13dd3b DM |
5191 | #ifdef CONFIG_FAILSLAB |
5192 | &failslab_attr.attr, | |
5193 | #endif | |
5194 | ||
81819f0f CL |
5195 | NULL |
5196 | }; | |
5197 | ||
5198 | static struct attribute_group slab_attr_group = { | |
5199 | .attrs = slab_attrs, | |
5200 | }; | |
5201 | ||
5202 | static ssize_t slab_attr_show(struct kobject *kobj, | |
5203 | struct attribute *attr, | |
5204 | char *buf) | |
5205 | { | |
5206 | struct slab_attribute *attribute; | |
5207 | struct kmem_cache *s; | |
5208 | int err; | |
5209 | ||
5210 | attribute = to_slab_attr(attr); | |
5211 | s = to_slab(kobj); | |
5212 | ||
5213 | if (!attribute->show) | |
5214 | return -EIO; | |
5215 | ||
5216 | err = attribute->show(s, buf); | |
5217 | ||
5218 | return err; | |
5219 | } | |
5220 | ||
5221 | static ssize_t slab_attr_store(struct kobject *kobj, | |
5222 | struct attribute *attr, | |
5223 | const char *buf, size_t len) | |
5224 | { | |
5225 | struct slab_attribute *attribute; | |
5226 | struct kmem_cache *s; | |
5227 | int err; | |
5228 | ||
5229 | attribute = to_slab_attr(attr); | |
5230 | s = to_slab(kobj); | |
5231 | ||
5232 | if (!attribute->store) | |
5233 | return -EIO; | |
5234 | ||
5235 | err = attribute->store(s, buf, len); | |
127424c8 | 5236 | #ifdef CONFIG_MEMCG |
107dab5c | 5237 | if (slab_state >= FULL && err >= 0 && is_root_cache(s)) { |
426589f5 | 5238 | struct kmem_cache *c; |
81819f0f | 5239 | |
107dab5c GC |
5240 | mutex_lock(&slab_mutex); |
5241 | if (s->max_attr_size < len) | |
5242 | s->max_attr_size = len; | |
5243 | ||
ebe945c2 GC |
5244 | /* |
5245 | * This is a best effort propagation, so this function's return | |
5246 | * value will be determined by the parent cache only. This is | |
5247 | * basically because not all attributes will have a well | |
5248 | * defined semantics for rollbacks - most of the actions will | |
5249 | * have permanent effects. | |
5250 | * | |
5251 | * Returning the error value of any of the children that fail | |
5252 | * is not 100 % defined, in the sense that users seeing the | |
5253 | * error code won't be able to know anything about the state of | |
5254 | * the cache. | |
5255 | * | |
5256 | * Only returning the error code for the parent cache at least | |
5257 | * has well defined semantics. The cache being written to | |
5258 | * directly either failed or succeeded, in which case we loop | |
5259 | * through the descendants with best-effort propagation. | |
5260 | */ | |
426589f5 VD |
5261 | for_each_memcg_cache(c, s) |
5262 | attribute->store(c, buf, len); | |
107dab5c GC |
5263 | mutex_unlock(&slab_mutex); |
5264 | } | |
5265 | #endif | |
81819f0f CL |
5266 | return err; |
5267 | } | |
5268 | ||
107dab5c GC |
5269 | static void memcg_propagate_slab_attrs(struct kmem_cache *s) |
5270 | { | |
127424c8 | 5271 | #ifdef CONFIG_MEMCG |
107dab5c GC |
5272 | int i; |
5273 | char *buffer = NULL; | |
93030d83 | 5274 | struct kmem_cache *root_cache; |
107dab5c | 5275 | |
93030d83 | 5276 | if (is_root_cache(s)) |
107dab5c GC |
5277 | return; |
5278 | ||
f7ce3190 | 5279 | root_cache = s->memcg_params.root_cache; |
93030d83 | 5280 | |
107dab5c GC |
5281 | /* |
5282 | * This mean this cache had no attribute written. Therefore, no point | |
5283 | * in copying default values around | |
5284 | */ | |
93030d83 | 5285 | if (!root_cache->max_attr_size) |
107dab5c GC |
5286 | return; |
5287 | ||
5288 | for (i = 0; i < ARRAY_SIZE(slab_attrs); i++) { | |
5289 | char mbuf[64]; | |
5290 | char *buf; | |
5291 | struct slab_attribute *attr = to_slab_attr(slab_attrs[i]); | |
5292 | ||
5293 | if (!attr || !attr->store || !attr->show) | |
5294 | continue; | |
5295 | ||
5296 | /* | |
5297 | * It is really bad that we have to allocate here, so we will | |
5298 | * do it only as a fallback. If we actually allocate, though, | |
5299 | * we can just use the allocated buffer until the end. | |
5300 | * | |
5301 | * Most of the slub attributes will tend to be very small in | |
5302 | * size, but sysfs allows buffers up to a page, so they can | |
5303 | * theoretically happen. | |
5304 | */ | |
5305 | if (buffer) | |
5306 | buf = buffer; | |
93030d83 | 5307 | else if (root_cache->max_attr_size < ARRAY_SIZE(mbuf)) |
107dab5c GC |
5308 | buf = mbuf; |
5309 | else { | |
5310 | buffer = (char *) get_zeroed_page(GFP_KERNEL); | |
5311 | if (WARN_ON(!buffer)) | |
5312 | continue; | |
5313 | buf = buffer; | |
5314 | } | |
5315 | ||
93030d83 | 5316 | attr->show(root_cache, buf); |
107dab5c GC |
5317 | attr->store(s, buf, strlen(buf)); |
5318 | } | |
5319 | ||
5320 | if (buffer) | |
5321 | free_page((unsigned long)buffer); | |
5322 | #endif | |
5323 | } | |
5324 | ||
41a21285 CL |
5325 | static void kmem_cache_release(struct kobject *k) |
5326 | { | |
5327 | slab_kmem_cache_release(to_slab(k)); | |
5328 | } | |
5329 | ||
52cf25d0 | 5330 | static const struct sysfs_ops slab_sysfs_ops = { |
81819f0f CL |
5331 | .show = slab_attr_show, |
5332 | .store = slab_attr_store, | |
5333 | }; | |
5334 | ||
5335 | static struct kobj_type slab_ktype = { | |
5336 | .sysfs_ops = &slab_sysfs_ops, | |
41a21285 | 5337 | .release = kmem_cache_release, |
81819f0f CL |
5338 | }; |
5339 | ||
5340 | static int uevent_filter(struct kset *kset, struct kobject *kobj) | |
5341 | { | |
5342 | struct kobj_type *ktype = get_ktype(kobj); | |
5343 | ||
5344 | if (ktype == &slab_ktype) | |
5345 | return 1; | |
5346 | return 0; | |
5347 | } | |
5348 | ||
9cd43611 | 5349 | static const struct kset_uevent_ops slab_uevent_ops = { |
81819f0f CL |
5350 | .filter = uevent_filter, |
5351 | }; | |
5352 | ||
27c3a314 | 5353 | static struct kset *slab_kset; |
81819f0f | 5354 | |
9a41707b VD |
5355 | static inline struct kset *cache_kset(struct kmem_cache *s) |
5356 | { | |
127424c8 | 5357 | #ifdef CONFIG_MEMCG |
9a41707b | 5358 | if (!is_root_cache(s)) |
f7ce3190 | 5359 | return s->memcg_params.root_cache->memcg_kset; |
9a41707b VD |
5360 | #endif |
5361 | return slab_kset; | |
5362 | } | |
5363 | ||
81819f0f CL |
5364 | #define ID_STR_LENGTH 64 |
5365 | ||
5366 | /* Create a unique string id for a slab cache: | |
6446faa2 CL |
5367 | * |
5368 | * Format :[flags-]size | |
81819f0f CL |
5369 | */ |
5370 | static char *create_unique_id(struct kmem_cache *s) | |
5371 | { | |
5372 | char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); | |
5373 | char *p = name; | |
5374 | ||
5375 | BUG_ON(!name); | |
5376 | ||
5377 | *p++ = ':'; | |
5378 | /* | |
5379 | * First flags affecting slabcache operations. We will only | |
5380 | * get here for aliasable slabs so we do not need to support | |
5381 | * too many flags. The flags here must cover all flags that | |
5382 | * are matched during merging to guarantee that the id is | |
5383 | * unique. | |
5384 | */ | |
5385 | if (s->flags & SLAB_CACHE_DMA) | |
5386 | *p++ = 'd'; | |
5387 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
5388 | *p++ = 'a'; | |
becfda68 | 5389 | if (s->flags & SLAB_CONSISTENCY_CHECKS) |
81819f0f | 5390 | *p++ = 'F'; |
5a896d9e VN |
5391 | if (!(s->flags & SLAB_NOTRACK)) |
5392 | *p++ = 't'; | |
230e9fc2 VD |
5393 | if (s->flags & SLAB_ACCOUNT) |
5394 | *p++ = 'A'; | |
81819f0f CL |
5395 | if (p != name + 1) |
5396 | *p++ = '-'; | |
5397 | p += sprintf(p, "%07d", s->size); | |
2633d7a0 | 5398 | |
81819f0f CL |
5399 | BUG_ON(p > name + ID_STR_LENGTH - 1); |
5400 | return name; | |
5401 | } | |
5402 | ||
5403 | static int sysfs_slab_add(struct kmem_cache *s) | |
5404 | { | |
5405 | int err; | |
5406 | const char *name; | |
45530c44 | 5407 | int unmergeable = slab_unmergeable(s); |
81819f0f | 5408 | |
81819f0f CL |
5409 | if (unmergeable) { |
5410 | /* | |
5411 | * Slabcache can never be merged so we can use the name proper. | |
5412 | * This is typically the case for debug situations. In that | |
5413 | * case we can catch duplicate names easily. | |
5414 | */ | |
27c3a314 | 5415 | sysfs_remove_link(&slab_kset->kobj, s->name); |
81819f0f CL |
5416 | name = s->name; |
5417 | } else { | |
5418 | /* | |
5419 | * Create a unique name for the slab as a target | |
5420 | * for the symlinks. | |
5421 | */ | |
5422 | name = create_unique_id(s); | |
5423 | } | |
5424 | ||
9a41707b | 5425 | s->kobj.kset = cache_kset(s); |
26e4f205 | 5426 | err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); |
54b6a731 | 5427 | if (err) |
80da026a | 5428 | goto out; |
81819f0f CL |
5429 | |
5430 | err = sysfs_create_group(&s->kobj, &slab_attr_group); | |
54b6a731 DJ |
5431 | if (err) |
5432 | goto out_del_kobj; | |
9a41707b | 5433 | |
127424c8 | 5434 | #ifdef CONFIG_MEMCG |
9a41707b VD |
5435 | if (is_root_cache(s)) { |
5436 | s->memcg_kset = kset_create_and_add("cgroup", NULL, &s->kobj); | |
5437 | if (!s->memcg_kset) { | |
54b6a731 DJ |
5438 | err = -ENOMEM; |
5439 | goto out_del_kobj; | |
9a41707b VD |
5440 | } |
5441 | } | |
5442 | #endif | |
5443 | ||
81819f0f CL |
5444 | kobject_uevent(&s->kobj, KOBJ_ADD); |
5445 | if (!unmergeable) { | |
5446 | /* Setup first alias */ | |
5447 | sysfs_slab_alias(s, s->name); | |
81819f0f | 5448 | } |
54b6a731 DJ |
5449 | out: |
5450 | if (!unmergeable) | |
5451 | kfree(name); | |
5452 | return err; | |
5453 | out_del_kobj: | |
5454 | kobject_del(&s->kobj); | |
54b6a731 | 5455 | goto out; |
81819f0f CL |
5456 | } |
5457 | ||
41a21285 | 5458 | void sysfs_slab_remove(struct kmem_cache *s) |
81819f0f | 5459 | { |
97d06609 | 5460 | if (slab_state < FULL) |
2bce6485 CL |
5461 | /* |
5462 | * Sysfs has not been setup yet so no need to remove the | |
5463 | * cache from sysfs. | |
5464 | */ | |
5465 | return; | |
5466 | ||
127424c8 | 5467 | #ifdef CONFIG_MEMCG |
9a41707b VD |
5468 | kset_unregister(s->memcg_kset); |
5469 | #endif | |
81819f0f CL |
5470 | kobject_uevent(&s->kobj, KOBJ_REMOVE); |
5471 | kobject_del(&s->kobj); | |
151c602f | 5472 | kobject_put(&s->kobj); |
81819f0f CL |
5473 | } |
5474 | ||
5475 | /* | |
5476 | * Need to buffer aliases during bootup until sysfs becomes | |
9f6c708e | 5477 | * available lest we lose that information. |
81819f0f CL |
5478 | */ |
5479 | struct saved_alias { | |
5480 | struct kmem_cache *s; | |
5481 | const char *name; | |
5482 | struct saved_alias *next; | |
5483 | }; | |
5484 | ||
5af328a5 | 5485 | static struct saved_alias *alias_list; |
81819f0f CL |
5486 | |
5487 | static int sysfs_slab_alias(struct kmem_cache *s, const char *name) | |
5488 | { | |
5489 | struct saved_alias *al; | |
5490 | ||
97d06609 | 5491 | if (slab_state == FULL) { |
81819f0f CL |
5492 | /* |
5493 | * If we have a leftover link then remove it. | |
5494 | */ | |
27c3a314 GKH |
5495 | sysfs_remove_link(&slab_kset->kobj, name); |
5496 | return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); | |
81819f0f CL |
5497 | } |
5498 | ||
5499 | al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); | |
5500 | if (!al) | |
5501 | return -ENOMEM; | |
5502 | ||
5503 | al->s = s; | |
5504 | al->name = name; | |
5505 | al->next = alias_list; | |
5506 | alias_list = al; | |
5507 | return 0; | |
5508 | } | |
5509 | ||
5510 | static int __init slab_sysfs_init(void) | |
5511 | { | |
5b95a4ac | 5512 | struct kmem_cache *s; |
81819f0f CL |
5513 | int err; |
5514 | ||
18004c5d | 5515 | mutex_lock(&slab_mutex); |
2bce6485 | 5516 | |
0ff21e46 | 5517 | slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj); |
27c3a314 | 5518 | if (!slab_kset) { |
18004c5d | 5519 | mutex_unlock(&slab_mutex); |
f9f58285 | 5520 | pr_err("Cannot register slab subsystem.\n"); |
81819f0f CL |
5521 | return -ENOSYS; |
5522 | } | |
5523 | ||
97d06609 | 5524 | slab_state = FULL; |
26a7bd03 | 5525 | |
5b95a4ac | 5526 | list_for_each_entry(s, &slab_caches, list) { |
26a7bd03 | 5527 | err = sysfs_slab_add(s); |
5d540fb7 | 5528 | if (err) |
f9f58285 FF |
5529 | pr_err("SLUB: Unable to add boot slab %s to sysfs\n", |
5530 | s->name); | |
26a7bd03 | 5531 | } |
81819f0f CL |
5532 | |
5533 | while (alias_list) { | |
5534 | struct saved_alias *al = alias_list; | |
5535 | ||
5536 | alias_list = alias_list->next; | |
5537 | err = sysfs_slab_alias(al->s, al->name); | |
5d540fb7 | 5538 | if (err) |
f9f58285 FF |
5539 | pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", |
5540 | al->name); | |
81819f0f CL |
5541 | kfree(al); |
5542 | } | |
5543 | ||
18004c5d | 5544 | mutex_unlock(&slab_mutex); |
81819f0f CL |
5545 | resiliency_test(); |
5546 | return 0; | |
5547 | } | |
5548 | ||
5549 | __initcall(slab_sysfs_init); | |
ab4d5ed5 | 5550 | #endif /* CONFIG_SYSFS */ |
57ed3eda PE |
5551 | |
5552 | /* | |
5553 | * The /proc/slabinfo ABI | |
5554 | */ | |
158a9624 | 5555 | #ifdef CONFIG_SLABINFO |
0d7561c6 | 5556 | void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) |
57ed3eda | 5557 | { |
57ed3eda | 5558 | unsigned long nr_slabs = 0; |
205ab99d CL |
5559 | unsigned long nr_objs = 0; |
5560 | unsigned long nr_free = 0; | |
57ed3eda | 5561 | int node; |
fa45dc25 | 5562 | struct kmem_cache_node *n; |
57ed3eda | 5563 | |
fa45dc25 | 5564 | for_each_kmem_cache_node(s, node, n) { |
c17fd13e WL |
5565 | nr_slabs += node_nr_slabs(n); |
5566 | nr_objs += node_nr_objs(n); | |
205ab99d | 5567 | nr_free += count_partial(n, count_free); |
57ed3eda PE |
5568 | } |
5569 | ||
0d7561c6 GC |
5570 | sinfo->active_objs = nr_objs - nr_free; |
5571 | sinfo->num_objs = nr_objs; | |
5572 | sinfo->active_slabs = nr_slabs; | |
5573 | sinfo->num_slabs = nr_slabs; | |
5574 | sinfo->objects_per_slab = oo_objects(s->oo); | |
5575 | sinfo->cache_order = oo_order(s->oo); | |
57ed3eda PE |
5576 | } |
5577 | ||
0d7561c6 | 5578 | void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) |
7b3c3a50 | 5579 | { |
7b3c3a50 AD |
5580 | } |
5581 | ||
b7454ad3 GC |
5582 | ssize_t slabinfo_write(struct file *file, const char __user *buffer, |
5583 | size_t count, loff_t *ppos) | |
7b3c3a50 | 5584 | { |
b7454ad3 | 5585 | return -EIO; |
7b3c3a50 | 5586 | } |
158a9624 | 5587 | #endif /* CONFIG_SLABINFO */ |