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Commit | Line | Data |
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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> |
5a896d9e | 23 | #include <linux/kmemcheck.h> |
81819f0f CL |
24 | #include <linux/cpu.h> |
25 | #include <linux/cpuset.h> | |
26 | #include <linux/mempolicy.h> | |
27 | #include <linux/ctype.h> | |
3ac7fe5a | 28 | #include <linux/debugobjects.h> |
81819f0f | 29 | #include <linux/kallsyms.h> |
b9049e23 | 30 | #include <linux/memory.h> |
f8bd2258 | 31 | #include <linux/math64.h> |
773ff60e | 32 | #include <linux/fault-inject.h> |
bfa71457 | 33 | #include <linux/stacktrace.h> |
4de900b4 | 34 | #include <linux/prefetch.h> |
2633d7a0 | 35 | #include <linux/memcontrol.h> |
81819f0f | 36 | |
4a92379b RK |
37 | #include <trace/events/kmem.h> |
38 | ||
072bb0aa MG |
39 | #include "internal.h" |
40 | ||
81819f0f CL |
41 | /* |
42 | * Lock order: | |
18004c5d | 43 | * 1. slab_mutex (Global Mutex) |
881db7fb CL |
44 | * 2. node->list_lock |
45 | * 3. slab_lock(page) (Only on some arches and for debugging) | |
81819f0f | 46 | * |
18004c5d | 47 | * slab_mutex |
881db7fb | 48 | * |
18004c5d | 49 | * The role of the slab_mutex is to protect the list of all the slabs |
881db7fb CL |
50 | * and to synchronize major metadata changes to slab cache structures. |
51 | * | |
52 | * The slab_lock is only used for debugging and on arches that do not | |
53 | * have the ability to do a cmpxchg_double. It only protects the second | |
54 | * double word in the page struct. Meaning | |
55 | * A. page->freelist -> List of object free in a page | |
56 | * B. page->counters -> Counters of objects | |
57 | * C. page->frozen -> frozen state | |
58 | * | |
59 | * If a slab is frozen then it is exempt from list management. It is not | |
60 | * on any list. The processor that froze the slab is the one who can | |
61 | * perform list operations on the page. Other processors may put objects | |
62 | * onto the freelist but the processor that froze the slab is the only | |
63 | * one that can retrieve the objects from the page's freelist. | |
81819f0f CL |
64 | * |
65 | * The list_lock protects the partial and full list on each node and | |
66 | * the partial slab counter. If taken then no new slabs may be added or | |
67 | * removed from the lists nor make the number of partial slabs be modified. | |
68 | * (Note that the total number of slabs is an atomic value that may be | |
69 | * modified without taking the list lock). | |
70 | * | |
71 | * The list_lock is a centralized lock and thus we avoid taking it as | |
72 | * much as possible. As long as SLUB does not have to handle partial | |
73 | * slabs, operations can continue without any centralized lock. F.e. | |
74 | * allocating a long series of objects that fill up slabs does not require | |
75 | * the list lock. | |
81819f0f CL |
76 | * Interrupts are disabled during allocation and deallocation in order to |
77 | * make the slab allocator safe to use in the context of an irq. In addition | |
78 | * interrupts are disabled to ensure that the processor does not change | |
79 | * while handling per_cpu slabs, due to kernel preemption. | |
80 | * | |
81 | * SLUB assigns one slab for allocation to each processor. | |
82 | * Allocations only occur from these slabs called cpu slabs. | |
83 | * | |
672bba3a CL |
84 | * Slabs with free elements are kept on a partial list and during regular |
85 | * operations no list for full slabs is used. If an object in a full slab is | |
81819f0f | 86 | * freed then the slab will show up again on the partial lists. |
672bba3a CL |
87 | * We track full slabs for debugging purposes though because otherwise we |
88 | * cannot scan all objects. | |
81819f0f CL |
89 | * |
90 | * Slabs are freed when they become empty. Teardown and setup is | |
91 | * minimal so we rely on the page allocators per cpu caches for | |
92 | * fast frees and allocs. | |
93 | * | |
94 | * Overloading of page flags that are otherwise used for LRU management. | |
95 | * | |
4b6f0750 CL |
96 | * PageActive The slab is frozen and exempt from list processing. |
97 | * This means that the slab is dedicated to a purpose | |
98 | * such as satisfying allocations for a specific | |
99 | * processor. Objects may be freed in the slab while | |
100 | * it is frozen but slab_free will then skip the usual | |
101 | * list operations. It is up to the processor holding | |
102 | * the slab to integrate the slab into the slab lists | |
103 | * when the slab is no longer needed. | |
104 | * | |
105 | * One use of this flag is to mark slabs that are | |
106 | * used for allocations. Then such a slab becomes a cpu | |
107 | * slab. The cpu slab may be equipped with an additional | |
dfb4f096 | 108 | * freelist that allows lockless access to |
894b8788 CL |
109 | * free objects in addition to the regular freelist |
110 | * that requires the slab lock. | |
81819f0f CL |
111 | * |
112 | * PageError Slab requires special handling due to debug | |
113 | * options set. This moves slab handling out of | |
894b8788 | 114 | * the fast path and disables lockless freelists. |
81819f0f CL |
115 | */ |
116 | ||
af537b0a CL |
117 | static inline int kmem_cache_debug(struct kmem_cache *s) |
118 | { | |
5577bd8a | 119 | #ifdef CONFIG_SLUB_DEBUG |
af537b0a | 120 | return unlikely(s->flags & SLAB_DEBUG_FLAGS); |
5577bd8a | 121 | #else |
af537b0a | 122 | return 0; |
5577bd8a | 123 | #endif |
af537b0a | 124 | } |
5577bd8a | 125 | |
345c905d JK |
126 | static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) |
127 | { | |
128 | #ifdef CONFIG_SLUB_CPU_PARTIAL | |
129 | return !kmem_cache_debug(s); | |
130 | #else | |
131 | return false; | |
132 | #endif | |
133 | } | |
134 | ||
81819f0f CL |
135 | /* |
136 | * Issues still to be resolved: | |
137 | * | |
81819f0f CL |
138 | * - Support PAGE_ALLOC_DEBUG. Should be easy to do. |
139 | * | |
81819f0f CL |
140 | * - Variable sizing of the per node arrays |
141 | */ | |
142 | ||
143 | /* Enable to test recovery from slab corruption on boot */ | |
144 | #undef SLUB_RESILIENCY_TEST | |
145 | ||
b789ef51 CL |
146 | /* Enable to log cmpxchg failures */ |
147 | #undef SLUB_DEBUG_CMPXCHG | |
148 | ||
2086d26a CL |
149 | /* |
150 | * Mininum number of partial slabs. These will be left on the partial | |
151 | * lists even if they are empty. kmem_cache_shrink may reclaim them. | |
152 | */ | |
76be8950 | 153 | #define MIN_PARTIAL 5 |
e95eed57 | 154 | |
2086d26a CL |
155 | /* |
156 | * Maximum number of desirable partial slabs. | |
157 | * The existence of more partial slabs makes kmem_cache_shrink | |
721ae22a | 158 | * sort the partial list by the number of objects in use. |
2086d26a CL |
159 | */ |
160 | #define MAX_PARTIAL 10 | |
161 | ||
81819f0f CL |
162 | #define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \ |
163 | SLAB_POISON | SLAB_STORE_USER) | |
672bba3a | 164 | |
fa5ec8a1 | 165 | /* |
3de47213 DR |
166 | * Debugging flags that require metadata to be stored in the slab. These get |
167 | * disabled when slub_debug=O is used and a cache's min order increases with | |
168 | * metadata. | |
fa5ec8a1 | 169 | */ |
3de47213 | 170 | #define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) |
fa5ec8a1 | 171 | |
210b5c06 CG |
172 | #define OO_SHIFT 16 |
173 | #define OO_MASK ((1 << OO_SHIFT) - 1) | |
50d5c41c | 174 | #define MAX_OBJS_PER_PAGE 32767 /* since page.objects is u15 */ |
210b5c06 | 175 | |
81819f0f | 176 | /* Internal SLUB flags */ |
f90ec390 | 177 | #define __OBJECT_POISON 0x80000000UL /* Poison object */ |
b789ef51 | 178 | #define __CMPXCHG_DOUBLE 0x40000000UL /* Use cmpxchg_double */ |
81819f0f | 179 | |
81819f0f CL |
180 | #ifdef CONFIG_SMP |
181 | static struct notifier_block slab_notifier; | |
182 | #endif | |
183 | ||
02cbc874 CL |
184 | /* |
185 | * Tracking user of a slab. | |
186 | */ | |
d6543e39 | 187 | #define TRACK_ADDRS_COUNT 16 |
02cbc874 | 188 | struct track { |
ce71e27c | 189 | unsigned long addr; /* Called from address */ |
d6543e39 BG |
190 | #ifdef CONFIG_STACKTRACE |
191 | unsigned long addrs[TRACK_ADDRS_COUNT]; /* Called from address */ | |
192 | #endif | |
02cbc874 CL |
193 | int cpu; /* Was running on cpu */ |
194 | int pid; /* Pid context */ | |
195 | unsigned long when; /* When did the operation occur */ | |
196 | }; | |
197 | ||
198 | enum track_item { TRACK_ALLOC, TRACK_FREE }; | |
199 | ||
ab4d5ed5 | 200 | #ifdef CONFIG_SYSFS |
81819f0f CL |
201 | static int sysfs_slab_add(struct kmem_cache *); |
202 | static int sysfs_slab_alias(struct kmem_cache *, const char *); | |
107dab5c | 203 | static void memcg_propagate_slab_attrs(struct kmem_cache *s); |
81819f0f | 204 | #else |
0c710013 CL |
205 | static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } |
206 | static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) | |
207 | { return 0; } | |
107dab5c | 208 | static inline void memcg_propagate_slab_attrs(struct kmem_cache *s) { } |
81819f0f CL |
209 | #endif |
210 | ||
4fdccdfb | 211 | static inline void stat(const struct kmem_cache *s, enum stat_item si) |
8ff12cfc CL |
212 | { |
213 | #ifdef CONFIG_SLUB_STATS | |
88da03a6 CL |
214 | /* |
215 | * The rmw is racy on a preemptible kernel but this is acceptable, so | |
216 | * avoid this_cpu_add()'s irq-disable overhead. | |
217 | */ | |
218 | raw_cpu_inc(s->cpu_slab->stat[si]); | |
8ff12cfc CL |
219 | #endif |
220 | } | |
221 | ||
81819f0f CL |
222 | /******************************************************************** |
223 | * Core slab cache functions | |
224 | *******************************************************************/ | |
225 | ||
6446faa2 | 226 | /* Verify that a pointer has an address that is valid within a slab page */ |
02cbc874 CL |
227 | static inline int check_valid_pointer(struct kmem_cache *s, |
228 | struct page *page, const void *object) | |
229 | { | |
230 | void *base; | |
231 | ||
a973e9dd | 232 | if (!object) |
02cbc874 CL |
233 | return 1; |
234 | ||
a973e9dd | 235 | base = page_address(page); |
39b26464 | 236 | if (object < base || object >= base + page->objects * s->size || |
02cbc874 CL |
237 | (object - base) % s->size) { |
238 | return 0; | |
239 | } | |
240 | ||
241 | return 1; | |
242 | } | |
243 | ||
7656c72b CL |
244 | static inline void *get_freepointer(struct kmem_cache *s, void *object) |
245 | { | |
246 | return *(void **)(object + s->offset); | |
247 | } | |
248 | ||
0ad9500e ED |
249 | static void prefetch_freepointer(const struct kmem_cache *s, void *object) |
250 | { | |
251 | prefetch(object + s->offset); | |
252 | } | |
253 | ||
1393d9a1 CL |
254 | static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) |
255 | { | |
256 | void *p; | |
257 | ||
258 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
259 | probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p)); | |
260 | #else | |
261 | p = get_freepointer(s, object); | |
262 | #endif | |
263 | return p; | |
264 | } | |
265 | ||
7656c72b CL |
266 | static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) |
267 | { | |
268 | *(void **)(object + s->offset) = fp; | |
269 | } | |
270 | ||
271 | /* Loop over all objects in a slab */ | |
224a88be CL |
272 | #define for_each_object(__p, __s, __addr, __objects) \ |
273 | for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\ | |
7656c72b CL |
274 | __p += (__s)->size) |
275 | ||
54266640 WY |
276 | #define for_each_object_idx(__p, __idx, __s, __addr, __objects) \ |
277 | for (__p = (__addr), __idx = 1; __idx <= __objects;\ | |
278 | __p += (__s)->size, __idx++) | |
279 | ||
7656c72b CL |
280 | /* Determine object index from a given position */ |
281 | static inline int slab_index(void *p, struct kmem_cache *s, void *addr) | |
282 | { | |
283 | return (p - addr) / s->size; | |
284 | } | |
285 | ||
d71f606f MK |
286 | static inline size_t slab_ksize(const struct kmem_cache *s) |
287 | { | |
288 | #ifdef CONFIG_SLUB_DEBUG | |
289 | /* | |
290 | * Debugging requires use of the padding between object | |
291 | * and whatever may come after it. | |
292 | */ | |
293 | if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) | |
3b0efdfa | 294 | return s->object_size; |
d71f606f MK |
295 | |
296 | #endif | |
297 | /* | |
298 | * If we have the need to store the freelist pointer | |
299 | * back there or track user information then we can | |
300 | * only use the space before that information. | |
301 | */ | |
302 | if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER)) | |
303 | return s->inuse; | |
304 | /* | |
305 | * Else we can use all the padding etc for the allocation | |
306 | */ | |
307 | return s->size; | |
308 | } | |
309 | ||
ab9a0f19 LJ |
310 | static inline int order_objects(int order, unsigned long size, int reserved) |
311 | { | |
312 | return ((PAGE_SIZE << order) - reserved) / size; | |
313 | } | |
314 | ||
834f3d11 | 315 | static inline struct kmem_cache_order_objects oo_make(int order, |
ab9a0f19 | 316 | unsigned long size, int reserved) |
834f3d11 CL |
317 | { |
318 | struct kmem_cache_order_objects x = { | |
ab9a0f19 | 319 | (order << OO_SHIFT) + order_objects(order, size, reserved) |
834f3d11 CL |
320 | }; |
321 | ||
322 | return x; | |
323 | } | |
324 | ||
325 | static inline int oo_order(struct kmem_cache_order_objects x) | |
326 | { | |
210b5c06 | 327 | return x.x >> OO_SHIFT; |
834f3d11 CL |
328 | } |
329 | ||
330 | static inline int oo_objects(struct kmem_cache_order_objects x) | |
331 | { | |
210b5c06 | 332 | return x.x & OO_MASK; |
834f3d11 CL |
333 | } |
334 | ||
881db7fb CL |
335 | /* |
336 | * Per slab locking using the pagelock | |
337 | */ | |
338 | static __always_inline void slab_lock(struct page *page) | |
339 | { | |
340 | bit_spin_lock(PG_locked, &page->flags); | |
341 | } | |
342 | ||
343 | static __always_inline void slab_unlock(struct page *page) | |
344 | { | |
345 | __bit_spin_unlock(PG_locked, &page->flags); | |
346 | } | |
347 | ||
a0320865 DH |
348 | static inline void set_page_slub_counters(struct page *page, unsigned long counters_new) |
349 | { | |
350 | struct page tmp; | |
351 | tmp.counters = counters_new; | |
352 | /* | |
353 | * page->counters can cover frozen/inuse/objects as well | |
354 | * as page->_count. If we assign to ->counters directly | |
355 | * we run the risk of losing updates to page->_count, so | |
356 | * be careful and only assign to the fields we need. | |
357 | */ | |
358 | page->frozen = tmp.frozen; | |
359 | page->inuse = tmp.inuse; | |
360 | page->objects = tmp.objects; | |
361 | } | |
362 | ||
1d07171c CL |
363 | /* Interrupts must be disabled (for the fallback code to work right) */ |
364 | static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page, | |
365 | void *freelist_old, unsigned long counters_old, | |
366 | void *freelist_new, unsigned long counters_new, | |
367 | const char *n) | |
368 | { | |
369 | VM_BUG_ON(!irqs_disabled()); | |
2565409f HC |
370 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
371 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
1d07171c | 372 | if (s->flags & __CMPXCHG_DOUBLE) { |
cdcd6298 | 373 | if (cmpxchg_double(&page->freelist, &page->counters, |
0aa9a13d DC |
374 | freelist_old, counters_old, |
375 | freelist_new, counters_new)) | |
376 | return 1; | |
1d07171c CL |
377 | } else |
378 | #endif | |
379 | { | |
380 | slab_lock(page); | |
d0e0ac97 CG |
381 | if (page->freelist == freelist_old && |
382 | page->counters == counters_old) { | |
1d07171c | 383 | page->freelist = freelist_new; |
a0320865 | 384 | set_page_slub_counters(page, counters_new); |
1d07171c CL |
385 | slab_unlock(page); |
386 | return 1; | |
387 | } | |
388 | slab_unlock(page); | |
389 | } | |
390 | ||
391 | cpu_relax(); | |
392 | stat(s, CMPXCHG_DOUBLE_FAIL); | |
393 | ||
394 | #ifdef SLUB_DEBUG_CMPXCHG | |
f9f58285 | 395 | pr_info("%s %s: cmpxchg double redo ", n, s->name); |
1d07171c CL |
396 | #endif |
397 | ||
398 | return 0; | |
399 | } | |
400 | ||
b789ef51 CL |
401 | static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page, |
402 | void *freelist_old, unsigned long counters_old, | |
403 | void *freelist_new, unsigned long counters_new, | |
404 | const char *n) | |
405 | { | |
2565409f HC |
406 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
407 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
b789ef51 | 408 | if (s->flags & __CMPXCHG_DOUBLE) { |
cdcd6298 | 409 | if (cmpxchg_double(&page->freelist, &page->counters, |
0aa9a13d DC |
410 | freelist_old, counters_old, |
411 | freelist_new, counters_new)) | |
412 | return 1; | |
b789ef51 CL |
413 | } else |
414 | #endif | |
415 | { | |
1d07171c CL |
416 | unsigned long flags; |
417 | ||
418 | local_irq_save(flags); | |
881db7fb | 419 | slab_lock(page); |
d0e0ac97 CG |
420 | if (page->freelist == freelist_old && |
421 | page->counters == counters_old) { | |
b789ef51 | 422 | page->freelist = freelist_new; |
a0320865 | 423 | set_page_slub_counters(page, counters_new); |
881db7fb | 424 | slab_unlock(page); |
1d07171c | 425 | local_irq_restore(flags); |
b789ef51 CL |
426 | return 1; |
427 | } | |
881db7fb | 428 | slab_unlock(page); |
1d07171c | 429 | local_irq_restore(flags); |
b789ef51 CL |
430 | } |
431 | ||
432 | cpu_relax(); | |
433 | stat(s, CMPXCHG_DOUBLE_FAIL); | |
434 | ||
435 | #ifdef SLUB_DEBUG_CMPXCHG | |
f9f58285 | 436 | pr_info("%s %s: cmpxchg double redo ", n, s->name); |
b789ef51 CL |
437 | #endif |
438 | ||
439 | return 0; | |
440 | } | |
441 | ||
41ecc55b | 442 | #ifdef CONFIG_SLUB_DEBUG |
5f80b13a CL |
443 | /* |
444 | * Determine a map of object in use on a page. | |
445 | * | |
881db7fb | 446 | * Node listlock must be held to guarantee that the page does |
5f80b13a CL |
447 | * not vanish from under us. |
448 | */ | |
449 | static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map) | |
450 | { | |
451 | void *p; | |
452 | void *addr = page_address(page); | |
453 | ||
454 | for (p = page->freelist; p; p = get_freepointer(s, p)) | |
455 | set_bit(slab_index(p, s, addr), map); | |
456 | } | |
457 | ||
41ecc55b CL |
458 | /* |
459 | * Debug settings: | |
460 | */ | |
f0630fff CL |
461 | #ifdef CONFIG_SLUB_DEBUG_ON |
462 | static int slub_debug = DEBUG_DEFAULT_FLAGS; | |
463 | #else | |
41ecc55b | 464 | static int slub_debug; |
f0630fff | 465 | #endif |
41ecc55b CL |
466 | |
467 | static char *slub_debug_slabs; | |
fa5ec8a1 | 468 | static int disable_higher_order_debug; |
41ecc55b | 469 | |
81819f0f CL |
470 | /* |
471 | * Object debugging | |
472 | */ | |
473 | static void print_section(char *text, u8 *addr, unsigned int length) | |
474 | { | |
ffc79d28 SAS |
475 | print_hex_dump(KERN_ERR, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, |
476 | length, 1); | |
81819f0f CL |
477 | } |
478 | ||
81819f0f CL |
479 | static struct track *get_track(struct kmem_cache *s, void *object, |
480 | enum track_item alloc) | |
481 | { | |
482 | struct track *p; | |
483 | ||
484 | if (s->offset) | |
485 | p = object + s->offset + sizeof(void *); | |
486 | else | |
487 | p = object + s->inuse; | |
488 | ||
489 | return p + alloc; | |
490 | } | |
491 | ||
492 | static void set_track(struct kmem_cache *s, void *object, | |
ce71e27c | 493 | enum track_item alloc, unsigned long addr) |
81819f0f | 494 | { |
1a00df4a | 495 | struct track *p = get_track(s, object, alloc); |
81819f0f | 496 | |
81819f0f | 497 | if (addr) { |
d6543e39 BG |
498 | #ifdef CONFIG_STACKTRACE |
499 | struct stack_trace trace; | |
500 | int i; | |
501 | ||
502 | trace.nr_entries = 0; | |
503 | trace.max_entries = TRACK_ADDRS_COUNT; | |
504 | trace.entries = p->addrs; | |
505 | trace.skip = 3; | |
506 | save_stack_trace(&trace); | |
507 | ||
508 | /* See rant in lockdep.c */ | |
509 | if (trace.nr_entries != 0 && | |
510 | trace.entries[trace.nr_entries - 1] == ULONG_MAX) | |
511 | trace.nr_entries--; | |
512 | ||
513 | for (i = trace.nr_entries; i < TRACK_ADDRS_COUNT; i++) | |
514 | p->addrs[i] = 0; | |
515 | #endif | |
81819f0f CL |
516 | p->addr = addr; |
517 | p->cpu = smp_processor_id(); | |
88e4ccf2 | 518 | p->pid = current->pid; |
81819f0f CL |
519 | p->when = jiffies; |
520 | } else | |
521 | memset(p, 0, sizeof(struct track)); | |
522 | } | |
523 | ||
81819f0f CL |
524 | static void init_tracking(struct kmem_cache *s, void *object) |
525 | { | |
24922684 CL |
526 | if (!(s->flags & SLAB_STORE_USER)) |
527 | return; | |
528 | ||
ce71e27c EGM |
529 | set_track(s, object, TRACK_FREE, 0UL); |
530 | set_track(s, object, TRACK_ALLOC, 0UL); | |
81819f0f CL |
531 | } |
532 | ||
533 | static void print_track(const char *s, struct track *t) | |
534 | { | |
535 | if (!t->addr) | |
536 | return; | |
537 | ||
f9f58285 FF |
538 | pr_err("INFO: %s in %pS age=%lu cpu=%u pid=%d\n", |
539 | s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid); | |
d6543e39 BG |
540 | #ifdef CONFIG_STACKTRACE |
541 | { | |
542 | int i; | |
543 | for (i = 0; i < TRACK_ADDRS_COUNT; i++) | |
544 | if (t->addrs[i]) | |
f9f58285 | 545 | pr_err("\t%pS\n", (void *)t->addrs[i]); |
d6543e39 BG |
546 | else |
547 | break; | |
548 | } | |
549 | #endif | |
24922684 CL |
550 | } |
551 | ||
552 | static void print_tracking(struct kmem_cache *s, void *object) | |
553 | { | |
554 | if (!(s->flags & SLAB_STORE_USER)) | |
555 | return; | |
556 | ||
557 | print_track("Allocated", get_track(s, object, TRACK_ALLOC)); | |
558 | print_track("Freed", get_track(s, object, TRACK_FREE)); | |
559 | } | |
560 | ||
561 | static void print_page_info(struct page *page) | |
562 | { | |
f9f58285 | 563 | pr_err("INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n", |
d0e0ac97 | 564 | page, page->objects, page->inuse, page->freelist, page->flags); |
24922684 CL |
565 | |
566 | } | |
567 | ||
568 | static void slab_bug(struct kmem_cache *s, char *fmt, ...) | |
569 | { | |
ecc42fbe | 570 | struct va_format vaf; |
24922684 | 571 | va_list args; |
24922684 CL |
572 | |
573 | va_start(args, fmt); | |
ecc42fbe FF |
574 | vaf.fmt = fmt; |
575 | vaf.va = &args; | |
f9f58285 | 576 | pr_err("=============================================================================\n"); |
ecc42fbe | 577 | pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); |
f9f58285 | 578 | pr_err("-----------------------------------------------------------------------------\n\n"); |
645df230 | 579 | |
373d4d09 | 580 | add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); |
ecc42fbe | 581 | va_end(args); |
81819f0f CL |
582 | } |
583 | ||
24922684 CL |
584 | static void slab_fix(struct kmem_cache *s, char *fmt, ...) |
585 | { | |
ecc42fbe | 586 | struct va_format vaf; |
24922684 | 587 | va_list args; |
24922684 CL |
588 | |
589 | va_start(args, fmt); | |
ecc42fbe FF |
590 | vaf.fmt = fmt; |
591 | vaf.va = &args; | |
592 | pr_err("FIX %s: %pV\n", s->name, &vaf); | |
24922684 | 593 | va_end(args); |
24922684 CL |
594 | } |
595 | ||
596 | static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) | |
81819f0f CL |
597 | { |
598 | unsigned int off; /* Offset of last byte */ | |
a973e9dd | 599 | u8 *addr = page_address(page); |
24922684 CL |
600 | |
601 | print_tracking(s, p); | |
602 | ||
603 | print_page_info(page); | |
604 | ||
f9f58285 FF |
605 | pr_err("INFO: Object 0x%p @offset=%tu fp=0x%p\n\n", |
606 | p, p - addr, get_freepointer(s, p)); | |
24922684 CL |
607 | |
608 | if (p > addr + 16) | |
ffc79d28 | 609 | print_section("Bytes b4 ", p - 16, 16); |
81819f0f | 610 | |
3b0efdfa | 611 | print_section("Object ", p, min_t(unsigned long, s->object_size, |
ffc79d28 | 612 | PAGE_SIZE)); |
81819f0f | 613 | if (s->flags & SLAB_RED_ZONE) |
3b0efdfa CL |
614 | print_section("Redzone ", p + s->object_size, |
615 | s->inuse - s->object_size); | |
81819f0f | 616 | |
81819f0f CL |
617 | if (s->offset) |
618 | off = s->offset + sizeof(void *); | |
619 | else | |
620 | off = s->inuse; | |
621 | ||
24922684 | 622 | if (s->flags & SLAB_STORE_USER) |
81819f0f | 623 | off += 2 * sizeof(struct track); |
81819f0f CL |
624 | |
625 | if (off != s->size) | |
626 | /* Beginning of the filler is the free pointer */ | |
ffc79d28 | 627 | print_section("Padding ", p + off, s->size - off); |
24922684 CL |
628 | |
629 | dump_stack(); | |
81819f0f CL |
630 | } |
631 | ||
632 | static void object_err(struct kmem_cache *s, struct page *page, | |
633 | u8 *object, char *reason) | |
634 | { | |
3dc50637 | 635 | slab_bug(s, "%s", reason); |
24922684 | 636 | print_trailer(s, page, object); |
81819f0f CL |
637 | } |
638 | ||
d0e0ac97 CG |
639 | static void slab_err(struct kmem_cache *s, struct page *page, |
640 | const char *fmt, ...) | |
81819f0f CL |
641 | { |
642 | va_list args; | |
643 | char buf[100]; | |
644 | ||
24922684 CL |
645 | va_start(args, fmt); |
646 | vsnprintf(buf, sizeof(buf), fmt, args); | |
81819f0f | 647 | va_end(args); |
3dc50637 | 648 | slab_bug(s, "%s", buf); |
24922684 | 649 | print_page_info(page); |
81819f0f CL |
650 | dump_stack(); |
651 | } | |
652 | ||
f7cb1933 | 653 | static void init_object(struct kmem_cache *s, void *object, u8 val) |
81819f0f CL |
654 | { |
655 | u8 *p = object; | |
656 | ||
657 | if (s->flags & __OBJECT_POISON) { | |
3b0efdfa CL |
658 | memset(p, POISON_FREE, s->object_size - 1); |
659 | p[s->object_size - 1] = POISON_END; | |
81819f0f CL |
660 | } |
661 | ||
662 | if (s->flags & SLAB_RED_ZONE) | |
3b0efdfa | 663 | memset(p + s->object_size, val, s->inuse - s->object_size); |
81819f0f CL |
664 | } |
665 | ||
24922684 CL |
666 | static void restore_bytes(struct kmem_cache *s, char *message, u8 data, |
667 | void *from, void *to) | |
668 | { | |
669 | slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data); | |
670 | memset(from, data, to - from); | |
671 | } | |
672 | ||
673 | static int check_bytes_and_report(struct kmem_cache *s, struct page *page, | |
674 | u8 *object, char *what, | |
06428780 | 675 | u8 *start, unsigned int value, unsigned int bytes) |
24922684 CL |
676 | { |
677 | u8 *fault; | |
678 | u8 *end; | |
679 | ||
79824820 | 680 | fault = memchr_inv(start, value, bytes); |
24922684 CL |
681 | if (!fault) |
682 | return 1; | |
683 | ||
684 | end = start + bytes; | |
685 | while (end > fault && end[-1] == value) | |
686 | end--; | |
687 | ||
688 | slab_bug(s, "%s overwritten", what); | |
f9f58285 | 689 | pr_err("INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n", |
24922684 CL |
690 | fault, end - 1, fault[0], value); |
691 | print_trailer(s, page, object); | |
692 | ||
693 | restore_bytes(s, what, value, fault, end); | |
694 | return 0; | |
81819f0f CL |
695 | } |
696 | ||
81819f0f CL |
697 | /* |
698 | * Object layout: | |
699 | * | |
700 | * object address | |
701 | * Bytes of the object to be managed. | |
702 | * If the freepointer may overlay the object then the free | |
703 | * pointer is the first word of the object. | |
672bba3a | 704 | * |
81819f0f CL |
705 | * Poisoning uses 0x6b (POISON_FREE) and the last byte is |
706 | * 0xa5 (POISON_END) | |
707 | * | |
3b0efdfa | 708 | * object + s->object_size |
81819f0f | 709 | * Padding to reach word boundary. This is also used for Redzoning. |
672bba3a | 710 | * Padding is extended by another word if Redzoning is enabled and |
3b0efdfa | 711 | * object_size == inuse. |
672bba3a | 712 | * |
81819f0f CL |
713 | * We fill with 0xbb (RED_INACTIVE) for inactive objects and with |
714 | * 0xcc (RED_ACTIVE) for objects in use. | |
715 | * | |
716 | * object + s->inuse | |
672bba3a CL |
717 | * Meta data starts here. |
718 | * | |
81819f0f CL |
719 | * A. Free pointer (if we cannot overwrite object on free) |
720 | * B. Tracking data for SLAB_STORE_USER | |
672bba3a | 721 | * C. Padding to reach required alignment boundary or at mininum |
6446faa2 | 722 | * one word if debugging is on to be able to detect writes |
672bba3a CL |
723 | * before the word boundary. |
724 | * | |
725 | * Padding is done using 0x5a (POISON_INUSE) | |
81819f0f CL |
726 | * |
727 | * object + s->size | |
672bba3a | 728 | * Nothing is used beyond s->size. |
81819f0f | 729 | * |
3b0efdfa | 730 | * If slabcaches are merged then the object_size and inuse boundaries are mostly |
672bba3a | 731 | * ignored. And therefore no slab options that rely on these boundaries |
81819f0f CL |
732 | * may be used with merged slabcaches. |
733 | */ | |
734 | ||
81819f0f CL |
735 | static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) |
736 | { | |
737 | unsigned long off = s->inuse; /* The end of info */ | |
738 | ||
739 | if (s->offset) | |
740 | /* Freepointer is placed after the object. */ | |
741 | off += sizeof(void *); | |
742 | ||
743 | if (s->flags & SLAB_STORE_USER) | |
744 | /* We also have user information there */ | |
745 | off += 2 * sizeof(struct track); | |
746 | ||
747 | if (s->size == off) | |
748 | return 1; | |
749 | ||
24922684 CL |
750 | return check_bytes_and_report(s, page, p, "Object padding", |
751 | p + off, POISON_INUSE, s->size - off); | |
81819f0f CL |
752 | } |
753 | ||
39b26464 | 754 | /* Check the pad bytes at the end of a slab page */ |
81819f0f CL |
755 | static int slab_pad_check(struct kmem_cache *s, struct page *page) |
756 | { | |
24922684 CL |
757 | u8 *start; |
758 | u8 *fault; | |
759 | u8 *end; | |
760 | int length; | |
761 | int remainder; | |
81819f0f CL |
762 | |
763 | if (!(s->flags & SLAB_POISON)) | |
764 | return 1; | |
765 | ||
a973e9dd | 766 | start = page_address(page); |
ab9a0f19 | 767 | length = (PAGE_SIZE << compound_order(page)) - s->reserved; |
39b26464 CL |
768 | end = start + length; |
769 | remainder = length % s->size; | |
81819f0f CL |
770 | if (!remainder) |
771 | return 1; | |
772 | ||
79824820 | 773 | fault = memchr_inv(end - remainder, POISON_INUSE, remainder); |
24922684 CL |
774 | if (!fault) |
775 | return 1; | |
776 | while (end > fault && end[-1] == POISON_INUSE) | |
777 | end--; | |
778 | ||
779 | slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); | |
ffc79d28 | 780 | print_section("Padding ", end - remainder, remainder); |
24922684 | 781 | |
8a3d271d | 782 | restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end); |
24922684 | 783 | return 0; |
81819f0f CL |
784 | } |
785 | ||
786 | static int check_object(struct kmem_cache *s, struct page *page, | |
f7cb1933 | 787 | void *object, u8 val) |
81819f0f CL |
788 | { |
789 | u8 *p = object; | |
3b0efdfa | 790 | u8 *endobject = object + s->object_size; |
81819f0f CL |
791 | |
792 | if (s->flags & SLAB_RED_ZONE) { | |
24922684 | 793 | if (!check_bytes_and_report(s, page, object, "Redzone", |
3b0efdfa | 794 | endobject, val, s->inuse - s->object_size)) |
81819f0f | 795 | return 0; |
81819f0f | 796 | } else { |
3b0efdfa | 797 | if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { |
3adbefee | 798 | check_bytes_and_report(s, page, p, "Alignment padding", |
d0e0ac97 CG |
799 | endobject, POISON_INUSE, |
800 | s->inuse - s->object_size); | |
3adbefee | 801 | } |
81819f0f CL |
802 | } |
803 | ||
804 | if (s->flags & SLAB_POISON) { | |
f7cb1933 | 805 | if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && |
24922684 | 806 | (!check_bytes_and_report(s, page, p, "Poison", p, |
3b0efdfa | 807 | POISON_FREE, s->object_size - 1) || |
24922684 | 808 | !check_bytes_and_report(s, page, p, "Poison", |
3b0efdfa | 809 | p + s->object_size - 1, POISON_END, 1))) |
81819f0f | 810 | return 0; |
81819f0f CL |
811 | /* |
812 | * check_pad_bytes cleans up on its own. | |
813 | */ | |
814 | check_pad_bytes(s, page, p); | |
815 | } | |
816 | ||
f7cb1933 | 817 | if (!s->offset && val == SLUB_RED_ACTIVE) |
81819f0f CL |
818 | /* |
819 | * Object and freepointer overlap. Cannot check | |
820 | * freepointer while object is allocated. | |
821 | */ | |
822 | return 1; | |
823 | ||
824 | /* Check free pointer validity */ | |
825 | if (!check_valid_pointer(s, page, get_freepointer(s, p))) { | |
826 | object_err(s, page, p, "Freepointer corrupt"); | |
827 | /* | |
9f6c708e | 828 | * No choice but to zap it and thus lose the remainder |
81819f0f | 829 | * of the free objects in this slab. May cause |
672bba3a | 830 | * another error because the object count is now wrong. |
81819f0f | 831 | */ |
a973e9dd | 832 | set_freepointer(s, p, NULL); |
81819f0f CL |
833 | return 0; |
834 | } | |
835 | return 1; | |
836 | } | |
837 | ||
838 | static int check_slab(struct kmem_cache *s, struct page *page) | |
839 | { | |
39b26464 CL |
840 | int maxobj; |
841 | ||
81819f0f CL |
842 | VM_BUG_ON(!irqs_disabled()); |
843 | ||
844 | if (!PageSlab(page)) { | |
24922684 | 845 | slab_err(s, page, "Not a valid slab page"); |
81819f0f CL |
846 | return 0; |
847 | } | |
39b26464 | 848 | |
ab9a0f19 | 849 | maxobj = order_objects(compound_order(page), s->size, s->reserved); |
39b26464 CL |
850 | if (page->objects > maxobj) { |
851 | slab_err(s, page, "objects %u > max %u", | |
f6edde9c | 852 | page->objects, maxobj); |
39b26464 CL |
853 | return 0; |
854 | } | |
855 | if (page->inuse > page->objects) { | |
24922684 | 856 | slab_err(s, page, "inuse %u > max %u", |
f6edde9c | 857 | page->inuse, page->objects); |
81819f0f CL |
858 | return 0; |
859 | } | |
860 | /* Slab_pad_check fixes things up after itself */ | |
861 | slab_pad_check(s, page); | |
862 | return 1; | |
863 | } | |
864 | ||
865 | /* | |
672bba3a CL |
866 | * Determine if a certain object on a page is on the freelist. Must hold the |
867 | * slab lock to guarantee that the chains are in a consistent state. | |
81819f0f CL |
868 | */ |
869 | static int on_freelist(struct kmem_cache *s, struct page *page, void *search) | |
870 | { | |
871 | int nr = 0; | |
881db7fb | 872 | void *fp; |
81819f0f | 873 | void *object = NULL; |
f6edde9c | 874 | int max_objects; |
81819f0f | 875 | |
881db7fb | 876 | fp = page->freelist; |
39b26464 | 877 | while (fp && nr <= page->objects) { |
81819f0f CL |
878 | if (fp == search) |
879 | return 1; | |
880 | if (!check_valid_pointer(s, page, fp)) { | |
881 | if (object) { | |
882 | object_err(s, page, object, | |
883 | "Freechain corrupt"); | |
a973e9dd | 884 | set_freepointer(s, object, NULL); |
81819f0f | 885 | } else { |
24922684 | 886 | slab_err(s, page, "Freepointer corrupt"); |
a973e9dd | 887 | page->freelist = NULL; |
39b26464 | 888 | page->inuse = page->objects; |
24922684 | 889 | slab_fix(s, "Freelist cleared"); |
81819f0f CL |
890 | return 0; |
891 | } | |
892 | break; | |
893 | } | |
894 | object = fp; | |
895 | fp = get_freepointer(s, object); | |
896 | nr++; | |
897 | } | |
898 | ||
ab9a0f19 | 899 | max_objects = order_objects(compound_order(page), s->size, s->reserved); |
210b5c06 CG |
900 | if (max_objects > MAX_OBJS_PER_PAGE) |
901 | max_objects = MAX_OBJS_PER_PAGE; | |
224a88be CL |
902 | |
903 | if (page->objects != max_objects) { | |
904 | slab_err(s, page, "Wrong number of objects. Found %d but " | |
905 | "should be %d", page->objects, max_objects); | |
906 | page->objects = max_objects; | |
907 | slab_fix(s, "Number of objects adjusted."); | |
908 | } | |
39b26464 | 909 | if (page->inuse != page->objects - nr) { |
70d71228 | 910 | slab_err(s, page, "Wrong object count. Counter is %d but " |
39b26464 CL |
911 | "counted were %d", page->inuse, page->objects - nr); |
912 | page->inuse = page->objects - nr; | |
24922684 | 913 | slab_fix(s, "Object count adjusted."); |
81819f0f CL |
914 | } |
915 | return search == NULL; | |
916 | } | |
917 | ||
0121c619 CL |
918 | static void trace(struct kmem_cache *s, struct page *page, void *object, |
919 | int alloc) | |
3ec09742 CL |
920 | { |
921 | if (s->flags & SLAB_TRACE) { | |
f9f58285 | 922 | pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", |
3ec09742 CL |
923 | s->name, |
924 | alloc ? "alloc" : "free", | |
925 | object, page->inuse, | |
926 | page->freelist); | |
927 | ||
928 | if (!alloc) | |
d0e0ac97 CG |
929 | print_section("Object ", (void *)object, |
930 | s->object_size); | |
3ec09742 CL |
931 | |
932 | dump_stack(); | |
933 | } | |
934 | } | |
935 | ||
643b1138 | 936 | /* |
672bba3a | 937 | * Tracking of fully allocated slabs for debugging purposes. |
643b1138 | 938 | */ |
5cc6eee8 CL |
939 | static void add_full(struct kmem_cache *s, |
940 | struct kmem_cache_node *n, struct page *page) | |
643b1138 | 941 | { |
5cc6eee8 CL |
942 | if (!(s->flags & SLAB_STORE_USER)) |
943 | return; | |
944 | ||
255d0884 | 945 | lockdep_assert_held(&n->list_lock); |
643b1138 | 946 | list_add(&page->lru, &n->full); |
643b1138 CL |
947 | } |
948 | ||
c65c1877 | 949 | static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct page *page) |
643b1138 | 950 | { |
643b1138 CL |
951 | if (!(s->flags & SLAB_STORE_USER)) |
952 | return; | |
953 | ||
255d0884 | 954 | lockdep_assert_held(&n->list_lock); |
643b1138 | 955 | list_del(&page->lru); |
643b1138 CL |
956 | } |
957 | ||
0f389ec6 CL |
958 | /* Tracking of the number of slabs for debugging purposes */ |
959 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) | |
960 | { | |
961 | struct kmem_cache_node *n = get_node(s, node); | |
962 | ||
963 | return atomic_long_read(&n->nr_slabs); | |
964 | } | |
965 | ||
26c02cf0 AB |
966 | static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) |
967 | { | |
968 | return atomic_long_read(&n->nr_slabs); | |
969 | } | |
970 | ||
205ab99d | 971 | static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
972 | { |
973 | struct kmem_cache_node *n = get_node(s, node); | |
974 | ||
975 | /* | |
976 | * May be called early in order to allocate a slab for the | |
977 | * kmem_cache_node structure. Solve the chicken-egg | |
978 | * dilemma by deferring the increment of the count during | |
979 | * bootstrap (see early_kmem_cache_node_alloc). | |
980 | */ | |
338b2642 | 981 | if (likely(n)) { |
0f389ec6 | 982 | atomic_long_inc(&n->nr_slabs); |
205ab99d CL |
983 | atomic_long_add(objects, &n->total_objects); |
984 | } | |
0f389ec6 | 985 | } |
205ab99d | 986 | static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
987 | { |
988 | struct kmem_cache_node *n = get_node(s, node); | |
989 | ||
990 | atomic_long_dec(&n->nr_slabs); | |
205ab99d | 991 | atomic_long_sub(objects, &n->total_objects); |
0f389ec6 CL |
992 | } |
993 | ||
994 | /* Object debug checks for alloc/free paths */ | |
3ec09742 CL |
995 | static void setup_object_debug(struct kmem_cache *s, struct page *page, |
996 | void *object) | |
997 | { | |
998 | if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON))) | |
999 | return; | |
1000 | ||
f7cb1933 | 1001 | init_object(s, object, SLUB_RED_INACTIVE); |
3ec09742 CL |
1002 | init_tracking(s, object); |
1003 | } | |
1004 | ||
d0e0ac97 CG |
1005 | static noinline int alloc_debug_processing(struct kmem_cache *s, |
1006 | struct page *page, | |
ce71e27c | 1007 | void *object, unsigned long addr) |
81819f0f CL |
1008 | { |
1009 | if (!check_slab(s, page)) | |
1010 | goto bad; | |
1011 | ||
81819f0f CL |
1012 | if (!check_valid_pointer(s, page, object)) { |
1013 | object_err(s, page, object, "Freelist Pointer check fails"); | |
70d71228 | 1014 | goto bad; |
81819f0f CL |
1015 | } |
1016 | ||
f7cb1933 | 1017 | if (!check_object(s, page, object, SLUB_RED_INACTIVE)) |
81819f0f | 1018 | goto bad; |
81819f0f | 1019 | |
3ec09742 CL |
1020 | /* Success perform special debug activities for allocs */ |
1021 | if (s->flags & SLAB_STORE_USER) | |
1022 | set_track(s, object, TRACK_ALLOC, addr); | |
1023 | trace(s, page, object, 1); | |
f7cb1933 | 1024 | init_object(s, object, SLUB_RED_ACTIVE); |
81819f0f | 1025 | return 1; |
3ec09742 | 1026 | |
81819f0f CL |
1027 | bad: |
1028 | if (PageSlab(page)) { | |
1029 | /* | |
1030 | * If this is a slab page then lets do the best we can | |
1031 | * to avoid issues in the future. Marking all objects | |
672bba3a | 1032 | * as used avoids touching the remaining objects. |
81819f0f | 1033 | */ |
24922684 | 1034 | slab_fix(s, "Marking all objects used"); |
39b26464 | 1035 | page->inuse = page->objects; |
a973e9dd | 1036 | page->freelist = NULL; |
81819f0f CL |
1037 | } |
1038 | return 0; | |
1039 | } | |
1040 | ||
19c7ff9e CL |
1041 | static noinline struct kmem_cache_node *free_debug_processing( |
1042 | struct kmem_cache *s, struct page *page, void *object, | |
1043 | unsigned long addr, unsigned long *flags) | |
81819f0f | 1044 | { |
19c7ff9e | 1045 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
5c2e4bbb | 1046 | |
19c7ff9e | 1047 | spin_lock_irqsave(&n->list_lock, *flags); |
881db7fb CL |
1048 | slab_lock(page); |
1049 | ||
81819f0f CL |
1050 | if (!check_slab(s, page)) |
1051 | goto fail; | |
1052 | ||
1053 | if (!check_valid_pointer(s, page, object)) { | |
70d71228 | 1054 | slab_err(s, page, "Invalid object pointer 0x%p", object); |
81819f0f CL |
1055 | goto fail; |
1056 | } | |
1057 | ||
1058 | if (on_freelist(s, page, object)) { | |
24922684 | 1059 | object_err(s, page, object, "Object already free"); |
81819f0f CL |
1060 | goto fail; |
1061 | } | |
1062 | ||
f7cb1933 | 1063 | if (!check_object(s, page, object, SLUB_RED_ACTIVE)) |
5c2e4bbb | 1064 | goto out; |
81819f0f | 1065 | |
1b4f59e3 | 1066 | if (unlikely(s != page->slab_cache)) { |
3adbefee | 1067 | if (!PageSlab(page)) { |
70d71228 CL |
1068 | slab_err(s, page, "Attempt to free object(0x%p) " |
1069 | "outside of slab", object); | |
1b4f59e3 | 1070 | } else if (!page->slab_cache) { |
f9f58285 FF |
1071 | pr_err("SLUB <none>: no slab for object 0x%p.\n", |
1072 | object); | |
70d71228 | 1073 | dump_stack(); |
06428780 | 1074 | } else |
24922684 CL |
1075 | object_err(s, page, object, |
1076 | "page slab pointer corrupt."); | |
81819f0f CL |
1077 | goto fail; |
1078 | } | |
3ec09742 | 1079 | |
3ec09742 CL |
1080 | if (s->flags & SLAB_STORE_USER) |
1081 | set_track(s, object, TRACK_FREE, addr); | |
1082 | trace(s, page, object, 0); | |
f7cb1933 | 1083 | init_object(s, object, SLUB_RED_INACTIVE); |
5c2e4bbb | 1084 | out: |
881db7fb | 1085 | slab_unlock(page); |
19c7ff9e CL |
1086 | /* |
1087 | * Keep node_lock to preserve integrity | |
1088 | * until the object is actually freed | |
1089 | */ | |
1090 | return n; | |
3ec09742 | 1091 | |
81819f0f | 1092 | fail: |
19c7ff9e CL |
1093 | slab_unlock(page); |
1094 | spin_unlock_irqrestore(&n->list_lock, *flags); | |
24922684 | 1095 | slab_fix(s, "Object at 0x%p not freed", object); |
19c7ff9e | 1096 | return NULL; |
81819f0f CL |
1097 | } |
1098 | ||
41ecc55b CL |
1099 | static int __init setup_slub_debug(char *str) |
1100 | { | |
f0630fff CL |
1101 | slub_debug = DEBUG_DEFAULT_FLAGS; |
1102 | if (*str++ != '=' || !*str) | |
1103 | /* | |
1104 | * No options specified. Switch on full debugging. | |
1105 | */ | |
1106 | goto out; | |
1107 | ||
1108 | if (*str == ',') | |
1109 | /* | |
1110 | * No options but restriction on slabs. This means full | |
1111 | * debugging for slabs matching a pattern. | |
1112 | */ | |
1113 | goto check_slabs; | |
1114 | ||
fa5ec8a1 DR |
1115 | if (tolower(*str) == 'o') { |
1116 | /* | |
1117 | * Avoid enabling debugging on caches if its minimum order | |
1118 | * would increase as a result. | |
1119 | */ | |
1120 | disable_higher_order_debug = 1; | |
1121 | goto out; | |
1122 | } | |
1123 | ||
f0630fff CL |
1124 | slub_debug = 0; |
1125 | if (*str == '-') | |
1126 | /* | |
1127 | * Switch off all debugging measures. | |
1128 | */ | |
1129 | goto out; | |
1130 | ||
1131 | /* | |
1132 | * Determine which debug features should be switched on | |
1133 | */ | |
06428780 | 1134 | for (; *str && *str != ','; str++) { |
f0630fff CL |
1135 | switch (tolower(*str)) { |
1136 | case 'f': | |
1137 | slub_debug |= SLAB_DEBUG_FREE; | |
1138 | break; | |
1139 | case 'z': | |
1140 | slub_debug |= SLAB_RED_ZONE; | |
1141 | break; | |
1142 | case 'p': | |
1143 | slub_debug |= SLAB_POISON; | |
1144 | break; | |
1145 | case 'u': | |
1146 | slub_debug |= SLAB_STORE_USER; | |
1147 | break; | |
1148 | case 't': | |
1149 | slub_debug |= SLAB_TRACE; | |
1150 | break; | |
4c13dd3b DM |
1151 | case 'a': |
1152 | slub_debug |= SLAB_FAILSLAB; | |
1153 | break; | |
f0630fff | 1154 | default: |
f9f58285 FF |
1155 | pr_err("slub_debug option '%c' unknown. skipped\n", |
1156 | *str); | |
f0630fff | 1157 | } |
41ecc55b CL |
1158 | } |
1159 | ||
f0630fff | 1160 | check_slabs: |
41ecc55b CL |
1161 | if (*str == ',') |
1162 | slub_debug_slabs = str + 1; | |
f0630fff | 1163 | out: |
41ecc55b CL |
1164 | return 1; |
1165 | } | |
1166 | ||
1167 | __setup("slub_debug", setup_slub_debug); | |
1168 | ||
423c929c | 1169 | unsigned long kmem_cache_flags(unsigned long object_size, |
ba0268a8 | 1170 | unsigned long flags, const char *name, |
51cc5068 | 1171 | void (*ctor)(void *)) |
41ecc55b CL |
1172 | { |
1173 | /* | |
e153362a | 1174 | * Enable debugging if selected on the kernel commandline. |
41ecc55b | 1175 | */ |
c6f58d9b CL |
1176 | if (slub_debug && (!slub_debug_slabs || (name && |
1177 | !strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs))))) | |
3de47213 | 1178 | flags |= slub_debug; |
ba0268a8 CL |
1179 | |
1180 | return flags; | |
41ecc55b CL |
1181 | } |
1182 | #else | |
3ec09742 CL |
1183 | static inline void setup_object_debug(struct kmem_cache *s, |
1184 | struct page *page, void *object) {} | |
41ecc55b | 1185 | |
3ec09742 | 1186 | static inline int alloc_debug_processing(struct kmem_cache *s, |
ce71e27c | 1187 | struct page *page, void *object, unsigned long addr) { return 0; } |
41ecc55b | 1188 | |
19c7ff9e CL |
1189 | static inline struct kmem_cache_node *free_debug_processing( |
1190 | struct kmem_cache *s, struct page *page, void *object, | |
1191 | unsigned long addr, unsigned long *flags) { return NULL; } | |
41ecc55b | 1192 | |
41ecc55b CL |
1193 | static inline int slab_pad_check(struct kmem_cache *s, struct page *page) |
1194 | { return 1; } | |
1195 | static inline int check_object(struct kmem_cache *s, struct page *page, | |
f7cb1933 | 1196 | void *object, u8 val) { return 1; } |
5cc6eee8 CL |
1197 | static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, |
1198 | struct page *page) {} | |
c65c1877 PZ |
1199 | static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, |
1200 | struct page *page) {} | |
423c929c | 1201 | unsigned long kmem_cache_flags(unsigned long object_size, |
ba0268a8 | 1202 | unsigned long flags, const char *name, |
51cc5068 | 1203 | void (*ctor)(void *)) |
ba0268a8 CL |
1204 | { |
1205 | return flags; | |
1206 | } | |
41ecc55b | 1207 | #define slub_debug 0 |
0f389ec6 | 1208 | |
fdaa45e9 IM |
1209 | #define disable_higher_order_debug 0 |
1210 | ||
0f389ec6 CL |
1211 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) |
1212 | { return 0; } | |
26c02cf0 AB |
1213 | static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) |
1214 | { return 0; } | |
205ab99d CL |
1215 | static inline void inc_slabs_node(struct kmem_cache *s, int node, |
1216 | int objects) {} | |
1217 | static inline void dec_slabs_node(struct kmem_cache *s, int node, | |
1218 | int objects) {} | |
7d550c56 | 1219 | |
02e72cc6 AR |
1220 | #endif /* CONFIG_SLUB_DEBUG */ |
1221 | ||
1222 | /* | |
1223 | * Hooks for other subsystems that check memory allocations. In a typical | |
1224 | * production configuration these hooks all should produce no code at all. | |
1225 | */ | |
d56791b3 RB |
1226 | static inline void kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags) |
1227 | { | |
1228 | kmemleak_alloc(ptr, size, 1, flags); | |
1229 | } | |
1230 | ||
1231 | static inline void kfree_hook(const void *x) | |
1232 | { | |
1233 | kmemleak_free(x); | |
1234 | } | |
1235 | ||
8135be5a VD |
1236 | static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, |
1237 | gfp_t flags) | |
02e72cc6 AR |
1238 | { |
1239 | flags &= gfp_allowed_mask; | |
1240 | lockdep_trace_alloc(flags); | |
1241 | might_sleep_if(flags & __GFP_WAIT); | |
7d550c56 | 1242 | |
8135be5a VD |
1243 | if (should_failslab(s->object_size, flags, s->flags)) |
1244 | return NULL; | |
1245 | ||
1246 | return memcg_kmem_get_cache(s, flags); | |
02e72cc6 AR |
1247 | } |
1248 | ||
1249 | static inline void slab_post_alloc_hook(struct kmem_cache *s, | |
1250 | gfp_t flags, void *object) | |
d56791b3 | 1251 | { |
02e72cc6 AR |
1252 | flags &= gfp_allowed_mask; |
1253 | kmemcheck_slab_alloc(s, flags, object, slab_ksize(s)); | |
1254 | kmemleak_alloc_recursive(object, s->object_size, 1, s->flags, flags); | |
8135be5a | 1255 | memcg_kmem_put_cache(s); |
d56791b3 | 1256 | } |
7d550c56 | 1257 | |
d56791b3 RB |
1258 | static inline void slab_free_hook(struct kmem_cache *s, void *x) |
1259 | { | |
1260 | kmemleak_free_recursive(x, s->flags); | |
7d550c56 | 1261 | |
02e72cc6 AR |
1262 | /* |
1263 | * Trouble is that we may no longer disable interrupts in the fast path | |
1264 | * So in order to make the debug calls that expect irqs to be | |
1265 | * disabled we need to disable interrupts temporarily. | |
1266 | */ | |
1267 | #if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP) | |
1268 | { | |
1269 | unsigned long flags; | |
1270 | ||
1271 | local_irq_save(flags); | |
1272 | kmemcheck_slab_free(s, x, s->object_size); | |
1273 | debug_check_no_locks_freed(x, s->object_size); | |
1274 | local_irq_restore(flags); | |
1275 | } | |
1276 | #endif | |
1277 | if (!(s->flags & SLAB_DEBUG_OBJECTS)) | |
1278 | debug_check_no_obj_freed(x, s->object_size); | |
1279 | } | |
205ab99d | 1280 | |
81819f0f CL |
1281 | /* |
1282 | * Slab allocation and freeing | |
1283 | */ | |
5dfb4175 VD |
1284 | static inline struct page *alloc_slab_page(struct kmem_cache *s, |
1285 | gfp_t flags, int node, struct kmem_cache_order_objects oo) | |
65c3376a | 1286 | { |
5dfb4175 | 1287 | struct page *page; |
65c3376a CL |
1288 | int order = oo_order(oo); |
1289 | ||
b1eeab67 VN |
1290 | flags |= __GFP_NOTRACK; |
1291 | ||
5dfb4175 VD |
1292 | if (memcg_charge_slab(s, flags, order)) |
1293 | return NULL; | |
1294 | ||
2154a336 | 1295 | if (node == NUMA_NO_NODE) |
5dfb4175 | 1296 | page = alloc_pages(flags, order); |
65c3376a | 1297 | else |
5dfb4175 VD |
1298 | page = alloc_pages_exact_node(node, flags, order); |
1299 | ||
1300 | if (!page) | |
1301 | memcg_uncharge_slab(s, order); | |
1302 | ||
1303 | return page; | |
65c3376a CL |
1304 | } |
1305 | ||
81819f0f CL |
1306 | static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) |
1307 | { | |
06428780 | 1308 | struct page *page; |
834f3d11 | 1309 | struct kmem_cache_order_objects oo = s->oo; |
ba52270d | 1310 | gfp_t alloc_gfp; |
81819f0f | 1311 | |
7e0528da CL |
1312 | flags &= gfp_allowed_mask; |
1313 | ||
1314 | if (flags & __GFP_WAIT) | |
1315 | local_irq_enable(); | |
1316 | ||
b7a49f0d | 1317 | flags |= s->allocflags; |
e12ba74d | 1318 | |
ba52270d PE |
1319 | /* |
1320 | * Let the initial higher-order allocation fail under memory pressure | |
1321 | * so we fall-back to the minimum order allocation. | |
1322 | */ | |
1323 | alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; | |
1324 | ||
5dfb4175 | 1325 | page = alloc_slab_page(s, alloc_gfp, node, oo); |
65c3376a CL |
1326 | if (unlikely(!page)) { |
1327 | oo = s->min; | |
80c3a998 | 1328 | alloc_gfp = flags; |
65c3376a CL |
1329 | /* |
1330 | * Allocation may have failed due to fragmentation. | |
1331 | * Try a lower order alloc if possible | |
1332 | */ | |
5dfb4175 | 1333 | page = alloc_slab_page(s, alloc_gfp, node, oo); |
81819f0f | 1334 | |
7e0528da CL |
1335 | if (page) |
1336 | stat(s, ORDER_FALLBACK); | |
65c3376a | 1337 | } |
5a896d9e | 1338 | |
737b719e | 1339 | if (kmemcheck_enabled && page |
5086c389 | 1340 | && !(s->flags & (SLAB_NOTRACK | DEBUG_DEFAULT_FLAGS))) { |
b1eeab67 VN |
1341 | int pages = 1 << oo_order(oo); |
1342 | ||
80c3a998 | 1343 | kmemcheck_alloc_shadow(page, oo_order(oo), alloc_gfp, node); |
b1eeab67 VN |
1344 | |
1345 | /* | |
1346 | * Objects from caches that have a constructor don't get | |
1347 | * cleared when they're allocated, so we need to do it here. | |
1348 | */ | |
1349 | if (s->ctor) | |
1350 | kmemcheck_mark_uninitialized_pages(page, pages); | |
1351 | else | |
1352 | kmemcheck_mark_unallocated_pages(page, pages); | |
5a896d9e VN |
1353 | } |
1354 | ||
737b719e DR |
1355 | if (flags & __GFP_WAIT) |
1356 | local_irq_disable(); | |
1357 | if (!page) | |
1358 | return NULL; | |
1359 | ||
834f3d11 | 1360 | page->objects = oo_objects(oo); |
81819f0f CL |
1361 | mod_zone_page_state(page_zone(page), |
1362 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? | |
1363 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
65c3376a | 1364 | 1 << oo_order(oo)); |
81819f0f CL |
1365 | |
1366 | return page; | |
1367 | } | |
1368 | ||
1369 | static void setup_object(struct kmem_cache *s, struct page *page, | |
1370 | void *object) | |
1371 | { | |
3ec09742 | 1372 | setup_object_debug(s, page, object); |
4f104934 | 1373 | if (unlikely(s->ctor)) |
51cc5068 | 1374 | s->ctor(object); |
81819f0f CL |
1375 | } |
1376 | ||
1377 | static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) | |
1378 | { | |
1379 | struct page *page; | |
81819f0f | 1380 | void *start; |
81819f0f | 1381 | void *p; |
1f458cbf | 1382 | int order; |
54266640 | 1383 | int idx; |
81819f0f | 1384 | |
c871ac4e AM |
1385 | if (unlikely(flags & GFP_SLAB_BUG_MASK)) { |
1386 | pr_emerg("gfp: %u\n", flags & GFP_SLAB_BUG_MASK); | |
1387 | BUG(); | |
1388 | } | |
81819f0f | 1389 | |
6cb06229 CL |
1390 | page = allocate_slab(s, |
1391 | flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); | |
81819f0f CL |
1392 | if (!page) |
1393 | goto out; | |
1394 | ||
1f458cbf | 1395 | order = compound_order(page); |
205ab99d | 1396 | inc_slabs_node(s, page_to_nid(page), page->objects); |
1b4f59e3 | 1397 | page->slab_cache = s; |
c03f94cc | 1398 | __SetPageSlab(page); |
072bb0aa MG |
1399 | if (page->pfmemalloc) |
1400 | SetPageSlabPfmemalloc(page); | |
81819f0f CL |
1401 | |
1402 | start = page_address(page); | |
81819f0f CL |
1403 | |
1404 | if (unlikely(s->flags & SLAB_POISON)) | |
1f458cbf | 1405 | memset(start, POISON_INUSE, PAGE_SIZE << order); |
81819f0f | 1406 | |
54266640 WY |
1407 | for_each_object_idx(p, idx, s, start, page->objects) { |
1408 | setup_object(s, page, p); | |
1409 | if (likely(idx < page->objects)) | |
1410 | set_freepointer(s, p, p + s->size); | |
1411 | else | |
1412 | set_freepointer(s, p, NULL); | |
81819f0f | 1413 | } |
81819f0f CL |
1414 | |
1415 | page->freelist = start; | |
e6e82ea1 | 1416 | page->inuse = page->objects; |
8cb0a506 | 1417 | page->frozen = 1; |
81819f0f | 1418 | out: |
81819f0f CL |
1419 | return page; |
1420 | } | |
1421 | ||
1422 | static void __free_slab(struct kmem_cache *s, struct page *page) | |
1423 | { | |
834f3d11 CL |
1424 | int order = compound_order(page); |
1425 | int pages = 1 << order; | |
81819f0f | 1426 | |
af537b0a | 1427 | if (kmem_cache_debug(s)) { |
81819f0f CL |
1428 | void *p; |
1429 | ||
1430 | slab_pad_check(s, page); | |
224a88be CL |
1431 | for_each_object(p, s, page_address(page), |
1432 | page->objects) | |
f7cb1933 | 1433 | check_object(s, page, p, SLUB_RED_INACTIVE); |
81819f0f CL |
1434 | } |
1435 | ||
b1eeab67 | 1436 | kmemcheck_free_shadow(page, compound_order(page)); |
5a896d9e | 1437 | |
81819f0f CL |
1438 | mod_zone_page_state(page_zone(page), |
1439 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? | |
1440 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
06428780 | 1441 | -pages); |
81819f0f | 1442 | |
072bb0aa | 1443 | __ClearPageSlabPfmemalloc(page); |
49bd5221 | 1444 | __ClearPageSlab(page); |
1f458cbf | 1445 | |
22b751c3 | 1446 | page_mapcount_reset(page); |
1eb5ac64 NP |
1447 | if (current->reclaim_state) |
1448 | current->reclaim_state->reclaimed_slab += pages; | |
5dfb4175 VD |
1449 | __free_pages(page, order); |
1450 | memcg_uncharge_slab(s, order); | |
81819f0f CL |
1451 | } |
1452 | ||
da9a638c LJ |
1453 | #define need_reserve_slab_rcu \ |
1454 | (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head)) | |
1455 | ||
81819f0f CL |
1456 | static void rcu_free_slab(struct rcu_head *h) |
1457 | { | |
1458 | struct page *page; | |
1459 | ||
da9a638c LJ |
1460 | if (need_reserve_slab_rcu) |
1461 | page = virt_to_head_page(h); | |
1462 | else | |
1463 | page = container_of((struct list_head *)h, struct page, lru); | |
1464 | ||
1b4f59e3 | 1465 | __free_slab(page->slab_cache, page); |
81819f0f CL |
1466 | } |
1467 | ||
1468 | static void free_slab(struct kmem_cache *s, struct page *page) | |
1469 | { | |
1470 | if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) { | |
da9a638c LJ |
1471 | struct rcu_head *head; |
1472 | ||
1473 | if (need_reserve_slab_rcu) { | |
1474 | int order = compound_order(page); | |
1475 | int offset = (PAGE_SIZE << order) - s->reserved; | |
1476 | ||
1477 | VM_BUG_ON(s->reserved != sizeof(*head)); | |
1478 | head = page_address(page) + offset; | |
1479 | } else { | |
1480 | /* | |
1481 | * RCU free overloads the RCU head over the LRU | |
1482 | */ | |
1483 | head = (void *)&page->lru; | |
1484 | } | |
81819f0f CL |
1485 | |
1486 | call_rcu(head, rcu_free_slab); | |
1487 | } else | |
1488 | __free_slab(s, page); | |
1489 | } | |
1490 | ||
1491 | static void discard_slab(struct kmem_cache *s, struct page *page) | |
1492 | { | |
205ab99d | 1493 | dec_slabs_node(s, page_to_nid(page), page->objects); |
81819f0f CL |
1494 | free_slab(s, page); |
1495 | } | |
1496 | ||
1497 | /* | |
5cc6eee8 | 1498 | * Management of partially allocated slabs. |
81819f0f | 1499 | */ |
1e4dd946 SR |
1500 | static inline void |
1501 | __add_partial(struct kmem_cache_node *n, struct page *page, int tail) | |
81819f0f | 1502 | { |
e95eed57 | 1503 | n->nr_partial++; |
136333d1 | 1504 | if (tail == DEACTIVATE_TO_TAIL) |
7c2e132c CL |
1505 | list_add_tail(&page->lru, &n->partial); |
1506 | else | |
1507 | list_add(&page->lru, &n->partial); | |
81819f0f CL |
1508 | } |
1509 | ||
1e4dd946 SR |
1510 | static inline void add_partial(struct kmem_cache_node *n, |
1511 | struct page *page, int tail) | |
62e346a8 | 1512 | { |
c65c1877 | 1513 | lockdep_assert_held(&n->list_lock); |
1e4dd946 SR |
1514 | __add_partial(n, page, tail); |
1515 | } | |
c65c1877 | 1516 | |
1e4dd946 SR |
1517 | static inline void |
1518 | __remove_partial(struct kmem_cache_node *n, struct page *page) | |
1519 | { | |
62e346a8 CL |
1520 | list_del(&page->lru); |
1521 | n->nr_partial--; | |
1522 | } | |
1523 | ||
1e4dd946 SR |
1524 | static inline void remove_partial(struct kmem_cache_node *n, |
1525 | struct page *page) | |
1526 | { | |
1527 | lockdep_assert_held(&n->list_lock); | |
1528 | __remove_partial(n, page); | |
1529 | } | |
1530 | ||
81819f0f | 1531 | /* |
7ced3719 CL |
1532 | * Remove slab from the partial list, freeze it and |
1533 | * return the pointer to the freelist. | |
81819f0f | 1534 | * |
497b66f2 | 1535 | * Returns a list of objects or NULL if it fails. |
81819f0f | 1536 | */ |
497b66f2 | 1537 | static inline void *acquire_slab(struct kmem_cache *s, |
acd19fd1 | 1538 | struct kmem_cache_node *n, struct page *page, |
633b0764 | 1539 | int mode, int *objects) |
81819f0f | 1540 | { |
2cfb7455 CL |
1541 | void *freelist; |
1542 | unsigned long counters; | |
1543 | struct page new; | |
1544 | ||
c65c1877 PZ |
1545 | lockdep_assert_held(&n->list_lock); |
1546 | ||
2cfb7455 CL |
1547 | /* |
1548 | * Zap the freelist and set the frozen bit. | |
1549 | * The old freelist is the list of objects for the | |
1550 | * per cpu allocation list. | |
1551 | */ | |
7ced3719 CL |
1552 | freelist = page->freelist; |
1553 | counters = page->counters; | |
1554 | new.counters = counters; | |
633b0764 | 1555 | *objects = new.objects - new.inuse; |
23910c50 | 1556 | if (mode) { |
7ced3719 | 1557 | new.inuse = page->objects; |
23910c50 PE |
1558 | new.freelist = NULL; |
1559 | } else { | |
1560 | new.freelist = freelist; | |
1561 | } | |
2cfb7455 | 1562 | |
a0132ac0 | 1563 | VM_BUG_ON(new.frozen); |
7ced3719 | 1564 | new.frozen = 1; |
2cfb7455 | 1565 | |
7ced3719 | 1566 | if (!__cmpxchg_double_slab(s, page, |
2cfb7455 | 1567 | freelist, counters, |
02d7633f | 1568 | new.freelist, new.counters, |
7ced3719 | 1569 | "acquire_slab")) |
7ced3719 | 1570 | return NULL; |
2cfb7455 CL |
1571 | |
1572 | remove_partial(n, page); | |
7ced3719 | 1573 | WARN_ON(!freelist); |
49e22585 | 1574 | return freelist; |
81819f0f CL |
1575 | } |
1576 | ||
633b0764 | 1577 | static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain); |
8ba00bb6 | 1578 | static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags); |
49e22585 | 1579 | |
81819f0f | 1580 | /* |
672bba3a | 1581 | * Try to allocate a partial slab from a specific node. |
81819f0f | 1582 | */ |
8ba00bb6 JK |
1583 | static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, |
1584 | struct kmem_cache_cpu *c, gfp_t flags) | |
81819f0f | 1585 | { |
49e22585 CL |
1586 | struct page *page, *page2; |
1587 | void *object = NULL; | |
633b0764 JK |
1588 | int available = 0; |
1589 | int objects; | |
81819f0f CL |
1590 | |
1591 | /* | |
1592 | * Racy check. If we mistakenly see no partial slabs then we | |
1593 | * just allocate an empty slab. If we mistakenly try to get a | |
672bba3a CL |
1594 | * partial slab and there is none available then get_partials() |
1595 | * will return NULL. | |
81819f0f CL |
1596 | */ |
1597 | if (!n || !n->nr_partial) | |
1598 | return NULL; | |
1599 | ||
1600 | spin_lock(&n->list_lock); | |
49e22585 | 1601 | list_for_each_entry_safe(page, page2, &n->partial, lru) { |
8ba00bb6 | 1602 | void *t; |
49e22585 | 1603 | |
8ba00bb6 JK |
1604 | if (!pfmemalloc_match(page, flags)) |
1605 | continue; | |
1606 | ||
633b0764 | 1607 | t = acquire_slab(s, n, page, object == NULL, &objects); |
49e22585 CL |
1608 | if (!t) |
1609 | break; | |
1610 | ||
633b0764 | 1611 | available += objects; |
12d79634 | 1612 | if (!object) { |
49e22585 | 1613 | c->page = page; |
49e22585 | 1614 | stat(s, ALLOC_FROM_PARTIAL); |
49e22585 | 1615 | object = t; |
49e22585 | 1616 | } else { |
633b0764 | 1617 | put_cpu_partial(s, page, 0); |
8028dcea | 1618 | stat(s, CPU_PARTIAL_NODE); |
49e22585 | 1619 | } |
345c905d JK |
1620 | if (!kmem_cache_has_cpu_partial(s) |
1621 | || available > s->cpu_partial / 2) | |
49e22585 CL |
1622 | break; |
1623 | ||
497b66f2 | 1624 | } |
81819f0f | 1625 | spin_unlock(&n->list_lock); |
497b66f2 | 1626 | return object; |
81819f0f CL |
1627 | } |
1628 | ||
1629 | /* | |
672bba3a | 1630 | * Get a page from somewhere. Search in increasing NUMA distances. |
81819f0f | 1631 | */ |
de3ec035 | 1632 | static void *get_any_partial(struct kmem_cache *s, gfp_t flags, |
acd19fd1 | 1633 | struct kmem_cache_cpu *c) |
81819f0f CL |
1634 | { |
1635 | #ifdef CONFIG_NUMA | |
1636 | struct zonelist *zonelist; | |
dd1a239f | 1637 | struct zoneref *z; |
54a6eb5c MG |
1638 | struct zone *zone; |
1639 | enum zone_type high_zoneidx = gfp_zone(flags); | |
497b66f2 | 1640 | void *object; |
cc9a6c87 | 1641 | unsigned int cpuset_mems_cookie; |
81819f0f CL |
1642 | |
1643 | /* | |
672bba3a CL |
1644 | * The defrag ratio allows a configuration of the tradeoffs between |
1645 | * inter node defragmentation and node local allocations. A lower | |
1646 | * defrag_ratio increases the tendency to do local allocations | |
1647 | * instead of attempting to obtain partial slabs from other nodes. | |
81819f0f | 1648 | * |
672bba3a CL |
1649 | * If the defrag_ratio is set to 0 then kmalloc() always |
1650 | * returns node local objects. If the ratio is higher then kmalloc() | |
1651 | * may return off node objects because partial slabs are obtained | |
1652 | * from other nodes and filled up. | |
81819f0f | 1653 | * |
6446faa2 | 1654 | * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes |
672bba3a CL |
1655 | * defrag_ratio = 1000) then every (well almost) allocation will |
1656 | * first attempt to defrag slab caches on other nodes. This means | |
1657 | * scanning over all nodes to look for partial slabs which may be | |
1658 | * expensive if we do it every time we are trying to find a slab | |
1659 | * with available objects. | |
81819f0f | 1660 | */ |
9824601e CL |
1661 | if (!s->remote_node_defrag_ratio || |
1662 | get_cycles() % 1024 > s->remote_node_defrag_ratio) | |
81819f0f CL |
1663 | return NULL; |
1664 | ||
cc9a6c87 | 1665 | do { |
d26914d1 | 1666 | cpuset_mems_cookie = read_mems_allowed_begin(); |
2a389610 | 1667 | zonelist = node_zonelist(mempolicy_slab_node(), flags); |
cc9a6c87 MG |
1668 | for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { |
1669 | struct kmem_cache_node *n; | |
1670 | ||
1671 | n = get_node(s, zone_to_nid(zone)); | |
1672 | ||
dee2f8aa | 1673 | if (n && cpuset_zone_allowed(zone, flags) && |
cc9a6c87 | 1674 | n->nr_partial > s->min_partial) { |
8ba00bb6 | 1675 | object = get_partial_node(s, n, c, flags); |
cc9a6c87 MG |
1676 | if (object) { |
1677 | /* | |
d26914d1 MG |
1678 | * Don't check read_mems_allowed_retry() |
1679 | * here - if mems_allowed was updated in | |
1680 | * parallel, that was a harmless race | |
1681 | * between allocation and the cpuset | |
1682 | * update | |
cc9a6c87 | 1683 | */ |
cc9a6c87 MG |
1684 | return object; |
1685 | } | |
c0ff7453 | 1686 | } |
81819f0f | 1687 | } |
d26914d1 | 1688 | } while (read_mems_allowed_retry(cpuset_mems_cookie)); |
81819f0f CL |
1689 | #endif |
1690 | return NULL; | |
1691 | } | |
1692 | ||
1693 | /* | |
1694 | * Get a partial page, lock it and return it. | |
1695 | */ | |
497b66f2 | 1696 | static void *get_partial(struct kmem_cache *s, gfp_t flags, int node, |
acd19fd1 | 1697 | struct kmem_cache_cpu *c) |
81819f0f | 1698 | { |
497b66f2 | 1699 | void *object; |
a561ce00 JK |
1700 | int searchnode = node; |
1701 | ||
1702 | if (node == NUMA_NO_NODE) | |
1703 | searchnode = numa_mem_id(); | |
1704 | else if (!node_present_pages(node)) | |
1705 | searchnode = node_to_mem_node(node); | |
81819f0f | 1706 | |
8ba00bb6 | 1707 | object = get_partial_node(s, get_node(s, searchnode), c, flags); |
497b66f2 CL |
1708 | if (object || node != NUMA_NO_NODE) |
1709 | return object; | |
81819f0f | 1710 | |
acd19fd1 | 1711 | return get_any_partial(s, flags, c); |
81819f0f CL |
1712 | } |
1713 | ||
8a5ec0ba CL |
1714 | #ifdef CONFIG_PREEMPT |
1715 | /* | |
1716 | * Calculate the next globally unique transaction for disambiguiation | |
1717 | * during cmpxchg. The transactions start with the cpu number and are then | |
1718 | * incremented by CONFIG_NR_CPUS. | |
1719 | */ | |
1720 | #define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) | |
1721 | #else | |
1722 | /* | |
1723 | * No preemption supported therefore also no need to check for | |
1724 | * different cpus. | |
1725 | */ | |
1726 | #define TID_STEP 1 | |
1727 | #endif | |
1728 | ||
1729 | static inline unsigned long next_tid(unsigned long tid) | |
1730 | { | |
1731 | return tid + TID_STEP; | |
1732 | } | |
1733 | ||
1734 | static inline unsigned int tid_to_cpu(unsigned long tid) | |
1735 | { | |
1736 | return tid % TID_STEP; | |
1737 | } | |
1738 | ||
1739 | static inline unsigned long tid_to_event(unsigned long tid) | |
1740 | { | |
1741 | return tid / TID_STEP; | |
1742 | } | |
1743 | ||
1744 | static inline unsigned int init_tid(int cpu) | |
1745 | { | |
1746 | return cpu; | |
1747 | } | |
1748 | ||
1749 | static inline void note_cmpxchg_failure(const char *n, | |
1750 | const struct kmem_cache *s, unsigned long tid) | |
1751 | { | |
1752 | #ifdef SLUB_DEBUG_CMPXCHG | |
1753 | unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); | |
1754 | ||
f9f58285 | 1755 | pr_info("%s %s: cmpxchg redo ", n, s->name); |
8a5ec0ba CL |
1756 | |
1757 | #ifdef CONFIG_PREEMPT | |
1758 | if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) | |
f9f58285 | 1759 | pr_warn("due to cpu change %d -> %d\n", |
8a5ec0ba CL |
1760 | tid_to_cpu(tid), tid_to_cpu(actual_tid)); |
1761 | else | |
1762 | #endif | |
1763 | if (tid_to_event(tid) != tid_to_event(actual_tid)) | |
f9f58285 | 1764 | pr_warn("due to cpu running other code. Event %ld->%ld\n", |
8a5ec0ba CL |
1765 | tid_to_event(tid), tid_to_event(actual_tid)); |
1766 | else | |
f9f58285 | 1767 | pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", |
8a5ec0ba CL |
1768 | actual_tid, tid, next_tid(tid)); |
1769 | #endif | |
4fdccdfb | 1770 | stat(s, CMPXCHG_DOUBLE_CPU_FAIL); |
8a5ec0ba CL |
1771 | } |
1772 | ||
788e1aad | 1773 | static void init_kmem_cache_cpus(struct kmem_cache *s) |
8a5ec0ba | 1774 | { |
8a5ec0ba CL |
1775 | int cpu; |
1776 | ||
1777 | for_each_possible_cpu(cpu) | |
1778 | per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu); | |
8a5ec0ba | 1779 | } |
2cfb7455 | 1780 | |
81819f0f CL |
1781 | /* |
1782 | * Remove the cpu slab | |
1783 | */ | |
d0e0ac97 CG |
1784 | static void deactivate_slab(struct kmem_cache *s, struct page *page, |
1785 | void *freelist) | |
81819f0f | 1786 | { |
2cfb7455 | 1787 | enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE }; |
2cfb7455 CL |
1788 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
1789 | int lock = 0; | |
1790 | enum slab_modes l = M_NONE, m = M_NONE; | |
2cfb7455 | 1791 | void *nextfree; |
136333d1 | 1792 | int tail = DEACTIVATE_TO_HEAD; |
2cfb7455 CL |
1793 | struct page new; |
1794 | struct page old; | |
1795 | ||
1796 | if (page->freelist) { | |
84e554e6 | 1797 | stat(s, DEACTIVATE_REMOTE_FREES); |
136333d1 | 1798 | tail = DEACTIVATE_TO_TAIL; |
2cfb7455 CL |
1799 | } |
1800 | ||
894b8788 | 1801 | /* |
2cfb7455 CL |
1802 | * Stage one: Free all available per cpu objects back |
1803 | * to the page freelist while it is still frozen. Leave the | |
1804 | * last one. | |
1805 | * | |
1806 | * There is no need to take the list->lock because the page | |
1807 | * is still frozen. | |
1808 | */ | |
1809 | while (freelist && (nextfree = get_freepointer(s, freelist))) { | |
1810 | void *prior; | |
1811 | unsigned long counters; | |
1812 | ||
1813 | do { | |
1814 | prior = page->freelist; | |
1815 | counters = page->counters; | |
1816 | set_freepointer(s, freelist, prior); | |
1817 | new.counters = counters; | |
1818 | new.inuse--; | |
a0132ac0 | 1819 | VM_BUG_ON(!new.frozen); |
2cfb7455 | 1820 | |
1d07171c | 1821 | } while (!__cmpxchg_double_slab(s, page, |
2cfb7455 CL |
1822 | prior, counters, |
1823 | freelist, new.counters, | |
1824 | "drain percpu freelist")); | |
1825 | ||
1826 | freelist = nextfree; | |
1827 | } | |
1828 | ||
894b8788 | 1829 | /* |
2cfb7455 CL |
1830 | * Stage two: Ensure that the page is unfrozen while the |
1831 | * list presence reflects the actual number of objects | |
1832 | * during unfreeze. | |
1833 | * | |
1834 | * We setup the list membership and then perform a cmpxchg | |
1835 | * with the count. If there is a mismatch then the page | |
1836 | * is not unfrozen but the page is on the wrong list. | |
1837 | * | |
1838 | * Then we restart the process which may have to remove | |
1839 | * the page from the list that we just put it on again | |
1840 | * because the number of objects in the slab may have | |
1841 | * changed. | |
894b8788 | 1842 | */ |
2cfb7455 | 1843 | redo: |
894b8788 | 1844 | |
2cfb7455 CL |
1845 | old.freelist = page->freelist; |
1846 | old.counters = page->counters; | |
a0132ac0 | 1847 | VM_BUG_ON(!old.frozen); |
7c2e132c | 1848 | |
2cfb7455 CL |
1849 | /* Determine target state of the slab */ |
1850 | new.counters = old.counters; | |
1851 | if (freelist) { | |
1852 | new.inuse--; | |
1853 | set_freepointer(s, freelist, old.freelist); | |
1854 | new.freelist = freelist; | |
1855 | } else | |
1856 | new.freelist = old.freelist; | |
1857 | ||
1858 | new.frozen = 0; | |
1859 | ||
8a5b20ae | 1860 | if (!new.inuse && n->nr_partial >= s->min_partial) |
2cfb7455 CL |
1861 | m = M_FREE; |
1862 | else if (new.freelist) { | |
1863 | m = M_PARTIAL; | |
1864 | if (!lock) { | |
1865 | lock = 1; | |
1866 | /* | |
1867 | * Taking the spinlock removes the possiblity | |
1868 | * that acquire_slab() will see a slab page that | |
1869 | * is frozen | |
1870 | */ | |
1871 | spin_lock(&n->list_lock); | |
1872 | } | |
1873 | } else { | |
1874 | m = M_FULL; | |
1875 | if (kmem_cache_debug(s) && !lock) { | |
1876 | lock = 1; | |
1877 | /* | |
1878 | * This also ensures that the scanning of full | |
1879 | * slabs from diagnostic functions will not see | |
1880 | * any frozen slabs. | |
1881 | */ | |
1882 | spin_lock(&n->list_lock); | |
1883 | } | |
1884 | } | |
1885 | ||
1886 | if (l != m) { | |
1887 | ||
1888 | if (l == M_PARTIAL) | |
1889 | ||
1890 | remove_partial(n, page); | |
1891 | ||
1892 | else if (l == M_FULL) | |
894b8788 | 1893 | |
c65c1877 | 1894 | remove_full(s, n, page); |
2cfb7455 CL |
1895 | |
1896 | if (m == M_PARTIAL) { | |
1897 | ||
1898 | add_partial(n, page, tail); | |
136333d1 | 1899 | stat(s, tail); |
2cfb7455 CL |
1900 | |
1901 | } else if (m == M_FULL) { | |
894b8788 | 1902 | |
2cfb7455 CL |
1903 | stat(s, DEACTIVATE_FULL); |
1904 | add_full(s, n, page); | |
1905 | ||
1906 | } | |
1907 | } | |
1908 | ||
1909 | l = m; | |
1d07171c | 1910 | if (!__cmpxchg_double_slab(s, page, |
2cfb7455 CL |
1911 | old.freelist, old.counters, |
1912 | new.freelist, new.counters, | |
1913 | "unfreezing slab")) | |
1914 | goto redo; | |
1915 | ||
2cfb7455 CL |
1916 | if (lock) |
1917 | spin_unlock(&n->list_lock); | |
1918 | ||
1919 | if (m == M_FREE) { | |
1920 | stat(s, DEACTIVATE_EMPTY); | |
1921 | discard_slab(s, page); | |
1922 | stat(s, FREE_SLAB); | |
894b8788 | 1923 | } |
81819f0f CL |
1924 | } |
1925 | ||
d24ac77f JK |
1926 | /* |
1927 | * Unfreeze all the cpu partial slabs. | |
1928 | * | |
59a09917 CL |
1929 | * This function must be called with interrupts disabled |
1930 | * for the cpu using c (or some other guarantee must be there | |
1931 | * to guarantee no concurrent accesses). | |
d24ac77f | 1932 | */ |
59a09917 CL |
1933 | static void unfreeze_partials(struct kmem_cache *s, |
1934 | struct kmem_cache_cpu *c) | |
49e22585 | 1935 | { |
345c905d | 1936 | #ifdef CONFIG_SLUB_CPU_PARTIAL |
43d77867 | 1937 | struct kmem_cache_node *n = NULL, *n2 = NULL; |
9ada1934 | 1938 | struct page *page, *discard_page = NULL; |
49e22585 CL |
1939 | |
1940 | while ((page = c->partial)) { | |
49e22585 CL |
1941 | struct page new; |
1942 | struct page old; | |
1943 | ||
1944 | c->partial = page->next; | |
43d77867 JK |
1945 | |
1946 | n2 = get_node(s, page_to_nid(page)); | |
1947 | if (n != n2) { | |
1948 | if (n) | |
1949 | spin_unlock(&n->list_lock); | |
1950 | ||
1951 | n = n2; | |
1952 | spin_lock(&n->list_lock); | |
1953 | } | |
49e22585 CL |
1954 | |
1955 | do { | |
1956 | ||
1957 | old.freelist = page->freelist; | |
1958 | old.counters = page->counters; | |
a0132ac0 | 1959 | VM_BUG_ON(!old.frozen); |
49e22585 CL |
1960 | |
1961 | new.counters = old.counters; | |
1962 | new.freelist = old.freelist; | |
1963 | ||
1964 | new.frozen = 0; | |
1965 | ||
d24ac77f | 1966 | } while (!__cmpxchg_double_slab(s, page, |
49e22585 CL |
1967 | old.freelist, old.counters, |
1968 | new.freelist, new.counters, | |
1969 | "unfreezing slab")); | |
1970 | ||
8a5b20ae | 1971 | if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { |
9ada1934 SL |
1972 | page->next = discard_page; |
1973 | discard_page = page; | |
43d77867 JK |
1974 | } else { |
1975 | add_partial(n, page, DEACTIVATE_TO_TAIL); | |
1976 | stat(s, FREE_ADD_PARTIAL); | |
49e22585 CL |
1977 | } |
1978 | } | |
1979 | ||
1980 | if (n) | |
1981 | spin_unlock(&n->list_lock); | |
9ada1934 SL |
1982 | |
1983 | while (discard_page) { | |
1984 | page = discard_page; | |
1985 | discard_page = discard_page->next; | |
1986 | ||
1987 | stat(s, DEACTIVATE_EMPTY); | |
1988 | discard_slab(s, page); | |
1989 | stat(s, FREE_SLAB); | |
1990 | } | |
345c905d | 1991 | #endif |
49e22585 CL |
1992 | } |
1993 | ||
1994 | /* | |
1995 | * Put a page that was just frozen (in __slab_free) into a partial page | |
1996 | * slot if available. This is done without interrupts disabled and without | |
1997 | * preemption disabled. The cmpxchg is racy and may put the partial page | |
1998 | * onto a random cpus partial slot. | |
1999 | * | |
2000 | * If we did not find a slot then simply move all the partials to the | |
2001 | * per node partial list. | |
2002 | */ | |
633b0764 | 2003 | static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) |
49e22585 | 2004 | { |
345c905d | 2005 | #ifdef CONFIG_SLUB_CPU_PARTIAL |
49e22585 CL |
2006 | struct page *oldpage; |
2007 | int pages; | |
2008 | int pobjects; | |
2009 | ||
2010 | do { | |
2011 | pages = 0; | |
2012 | pobjects = 0; | |
2013 | oldpage = this_cpu_read(s->cpu_slab->partial); | |
2014 | ||
2015 | if (oldpage) { | |
2016 | pobjects = oldpage->pobjects; | |
2017 | pages = oldpage->pages; | |
2018 | if (drain && pobjects > s->cpu_partial) { | |
2019 | unsigned long flags; | |
2020 | /* | |
2021 | * partial array is full. Move the existing | |
2022 | * set to the per node partial list. | |
2023 | */ | |
2024 | local_irq_save(flags); | |
59a09917 | 2025 | unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); |
49e22585 | 2026 | local_irq_restore(flags); |
e24fc410 | 2027 | oldpage = NULL; |
49e22585 CL |
2028 | pobjects = 0; |
2029 | pages = 0; | |
8028dcea | 2030 | stat(s, CPU_PARTIAL_DRAIN); |
49e22585 CL |
2031 | } |
2032 | } | |
2033 | ||
2034 | pages++; | |
2035 | pobjects += page->objects - page->inuse; | |
2036 | ||
2037 | page->pages = pages; | |
2038 | page->pobjects = pobjects; | |
2039 | page->next = oldpage; | |
2040 | ||
d0e0ac97 CG |
2041 | } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) |
2042 | != oldpage); | |
345c905d | 2043 | #endif |
49e22585 CL |
2044 | } |
2045 | ||
dfb4f096 | 2046 | static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) |
81819f0f | 2047 | { |
84e554e6 | 2048 | stat(s, CPUSLAB_FLUSH); |
c17dda40 CL |
2049 | deactivate_slab(s, c->page, c->freelist); |
2050 | ||
2051 | c->tid = next_tid(c->tid); | |
2052 | c->page = NULL; | |
2053 | c->freelist = NULL; | |
81819f0f CL |
2054 | } |
2055 | ||
2056 | /* | |
2057 | * Flush cpu slab. | |
6446faa2 | 2058 | * |
81819f0f CL |
2059 | * Called from IPI handler with interrupts disabled. |
2060 | */ | |
0c710013 | 2061 | static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) |
81819f0f | 2062 | { |
9dfc6e68 | 2063 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); |
81819f0f | 2064 | |
49e22585 CL |
2065 | if (likely(c)) { |
2066 | if (c->page) | |
2067 | flush_slab(s, c); | |
2068 | ||
59a09917 | 2069 | unfreeze_partials(s, c); |
49e22585 | 2070 | } |
81819f0f CL |
2071 | } |
2072 | ||
2073 | static void flush_cpu_slab(void *d) | |
2074 | { | |
2075 | struct kmem_cache *s = d; | |
81819f0f | 2076 | |
dfb4f096 | 2077 | __flush_cpu_slab(s, smp_processor_id()); |
81819f0f CL |
2078 | } |
2079 | ||
a8364d55 GBY |
2080 | static bool has_cpu_slab(int cpu, void *info) |
2081 | { | |
2082 | struct kmem_cache *s = info; | |
2083 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); | |
2084 | ||
02e1a9cd | 2085 | return c->page || c->partial; |
a8364d55 GBY |
2086 | } |
2087 | ||
81819f0f CL |
2088 | static void flush_all(struct kmem_cache *s) |
2089 | { | |
a8364d55 | 2090 | on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC); |
81819f0f CL |
2091 | } |
2092 | ||
dfb4f096 CL |
2093 | /* |
2094 | * Check if the objects in a per cpu structure fit numa | |
2095 | * locality expectations. | |
2096 | */ | |
57d437d2 | 2097 | static inline int node_match(struct page *page, int node) |
dfb4f096 CL |
2098 | { |
2099 | #ifdef CONFIG_NUMA | |
4d7868e6 | 2100 | if (!page || (node != NUMA_NO_NODE && page_to_nid(page) != node)) |
dfb4f096 CL |
2101 | return 0; |
2102 | #endif | |
2103 | return 1; | |
2104 | } | |
2105 | ||
9a02d699 | 2106 | #ifdef CONFIG_SLUB_DEBUG |
781b2ba6 PE |
2107 | static int count_free(struct page *page) |
2108 | { | |
2109 | return page->objects - page->inuse; | |
2110 | } | |
2111 | ||
9a02d699 DR |
2112 | static inline unsigned long node_nr_objs(struct kmem_cache_node *n) |
2113 | { | |
2114 | return atomic_long_read(&n->total_objects); | |
2115 | } | |
2116 | #endif /* CONFIG_SLUB_DEBUG */ | |
2117 | ||
2118 | #if defined(CONFIG_SLUB_DEBUG) || defined(CONFIG_SYSFS) | |
781b2ba6 PE |
2119 | static unsigned long count_partial(struct kmem_cache_node *n, |
2120 | int (*get_count)(struct page *)) | |
2121 | { | |
2122 | unsigned long flags; | |
2123 | unsigned long x = 0; | |
2124 | struct page *page; | |
2125 | ||
2126 | spin_lock_irqsave(&n->list_lock, flags); | |
2127 | list_for_each_entry(page, &n->partial, lru) | |
2128 | x += get_count(page); | |
2129 | spin_unlock_irqrestore(&n->list_lock, flags); | |
2130 | return x; | |
2131 | } | |
9a02d699 | 2132 | #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */ |
26c02cf0 | 2133 | |
781b2ba6 PE |
2134 | static noinline void |
2135 | slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) | |
2136 | { | |
9a02d699 DR |
2137 | #ifdef CONFIG_SLUB_DEBUG |
2138 | static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, | |
2139 | DEFAULT_RATELIMIT_BURST); | |
781b2ba6 | 2140 | int node; |
fa45dc25 | 2141 | struct kmem_cache_node *n; |
781b2ba6 | 2142 | |
9a02d699 DR |
2143 | if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) |
2144 | return; | |
2145 | ||
f9f58285 | 2146 | pr_warn("SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n", |
781b2ba6 | 2147 | nid, gfpflags); |
f9f58285 FF |
2148 | pr_warn(" cache: %s, object size: %d, buffer size: %d, default order: %d, min order: %d\n", |
2149 | s->name, s->object_size, s->size, oo_order(s->oo), | |
2150 | oo_order(s->min)); | |
781b2ba6 | 2151 | |
3b0efdfa | 2152 | if (oo_order(s->min) > get_order(s->object_size)) |
f9f58285 FF |
2153 | pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", |
2154 | s->name); | |
fa5ec8a1 | 2155 | |
fa45dc25 | 2156 | for_each_kmem_cache_node(s, node, n) { |
781b2ba6 PE |
2157 | unsigned long nr_slabs; |
2158 | unsigned long nr_objs; | |
2159 | unsigned long nr_free; | |
2160 | ||
26c02cf0 AB |
2161 | nr_free = count_partial(n, count_free); |
2162 | nr_slabs = node_nr_slabs(n); | |
2163 | nr_objs = node_nr_objs(n); | |
781b2ba6 | 2164 | |
f9f58285 | 2165 | pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", |
781b2ba6 PE |
2166 | node, nr_slabs, nr_objs, nr_free); |
2167 | } | |
9a02d699 | 2168 | #endif |
781b2ba6 PE |
2169 | } |
2170 | ||
497b66f2 CL |
2171 | static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags, |
2172 | int node, struct kmem_cache_cpu **pc) | |
2173 | { | |
6faa6833 | 2174 | void *freelist; |
188fd063 CL |
2175 | struct kmem_cache_cpu *c = *pc; |
2176 | struct page *page; | |
497b66f2 | 2177 | |
188fd063 | 2178 | freelist = get_partial(s, flags, node, c); |
497b66f2 | 2179 | |
188fd063 CL |
2180 | if (freelist) |
2181 | return freelist; | |
2182 | ||
2183 | page = new_slab(s, flags, node); | |
497b66f2 | 2184 | if (page) { |
7c8e0181 | 2185 | c = raw_cpu_ptr(s->cpu_slab); |
497b66f2 CL |
2186 | if (c->page) |
2187 | flush_slab(s, c); | |
2188 | ||
2189 | /* | |
2190 | * No other reference to the page yet so we can | |
2191 | * muck around with it freely without cmpxchg | |
2192 | */ | |
6faa6833 | 2193 | freelist = page->freelist; |
497b66f2 CL |
2194 | page->freelist = NULL; |
2195 | ||
2196 | stat(s, ALLOC_SLAB); | |
497b66f2 CL |
2197 | c->page = page; |
2198 | *pc = c; | |
2199 | } else | |
6faa6833 | 2200 | freelist = NULL; |
497b66f2 | 2201 | |
6faa6833 | 2202 | return freelist; |
497b66f2 CL |
2203 | } |
2204 | ||
072bb0aa MG |
2205 | static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags) |
2206 | { | |
2207 | if (unlikely(PageSlabPfmemalloc(page))) | |
2208 | return gfp_pfmemalloc_allowed(gfpflags); | |
2209 | ||
2210 | return true; | |
2211 | } | |
2212 | ||
213eeb9f | 2213 | /* |
d0e0ac97 CG |
2214 | * Check the page->freelist of a page and either transfer the freelist to the |
2215 | * per cpu freelist or deactivate the page. | |
213eeb9f CL |
2216 | * |
2217 | * The page is still frozen if the return value is not NULL. | |
2218 | * | |
2219 | * If this function returns NULL then the page has been unfrozen. | |
d24ac77f JK |
2220 | * |
2221 | * This function must be called with interrupt disabled. | |
213eeb9f CL |
2222 | */ |
2223 | static inline void *get_freelist(struct kmem_cache *s, struct page *page) | |
2224 | { | |
2225 | struct page new; | |
2226 | unsigned long counters; | |
2227 | void *freelist; | |
2228 | ||
2229 | do { | |
2230 | freelist = page->freelist; | |
2231 | counters = page->counters; | |
6faa6833 | 2232 | |
213eeb9f | 2233 | new.counters = counters; |
a0132ac0 | 2234 | VM_BUG_ON(!new.frozen); |
213eeb9f CL |
2235 | |
2236 | new.inuse = page->objects; | |
2237 | new.frozen = freelist != NULL; | |
2238 | ||
d24ac77f | 2239 | } while (!__cmpxchg_double_slab(s, page, |
213eeb9f CL |
2240 | freelist, counters, |
2241 | NULL, new.counters, | |
2242 | "get_freelist")); | |
2243 | ||
2244 | return freelist; | |
2245 | } | |
2246 | ||
81819f0f | 2247 | /* |
894b8788 CL |
2248 | * Slow path. The lockless freelist is empty or we need to perform |
2249 | * debugging duties. | |
2250 | * | |
894b8788 CL |
2251 | * Processing is still very fast if new objects have been freed to the |
2252 | * regular freelist. In that case we simply take over the regular freelist | |
2253 | * as the lockless freelist and zap the regular freelist. | |
81819f0f | 2254 | * |
894b8788 CL |
2255 | * If that is not working then we fall back to the partial lists. We take the |
2256 | * first element of the freelist as the object to allocate now and move the | |
2257 | * rest of the freelist to the lockless freelist. | |
81819f0f | 2258 | * |
894b8788 | 2259 | * And if we were unable to get a new slab from the partial slab lists then |
6446faa2 CL |
2260 | * we need to allocate a new slab. This is the slowest path since it involves |
2261 | * a call to the page allocator and the setup of a new slab. | |
81819f0f | 2262 | */ |
ce71e27c EGM |
2263 | static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, |
2264 | unsigned long addr, struct kmem_cache_cpu *c) | |
81819f0f | 2265 | { |
6faa6833 | 2266 | void *freelist; |
f6e7def7 | 2267 | struct page *page; |
8a5ec0ba CL |
2268 | unsigned long flags; |
2269 | ||
2270 | local_irq_save(flags); | |
2271 | #ifdef CONFIG_PREEMPT | |
2272 | /* | |
2273 | * We may have been preempted and rescheduled on a different | |
2274 | * cpu before disabling interrupts. Need to reload cpu area | |
2275 | * pointer. | |
2276 | */ | |
2277 | c = this_cpu_ptr(s->cpu_slab); | |
8a5ec0ba | 2278 | #endif |
81819f0f | 2279 | |
f6e7def7 CL |
2280 | page = c->page; |
2281 | if (!page) | |
81819f0f | 2282 | goto new_slab; |
49e22585 | 2283 | redo: |
6faa6833 | 2284 | |
57d437d2 | 2285 | if (unlikely(!node_match(page, node))) { |
a561ce00 JK |
2286 | int searchnode = node; |
2287 | ||
2288 | if (node != NUMA_NO_NODE && !node_present_pages(node)) | |
2289 | searchnode = node_to_mem_node(node); | |
2290 | ||
2291 | if (unlikely(!node_match(page, searchnode))) { | |
2292 | stat(s, ALLOC_NODE_MISMATCH); | |
2293 | deactivate_slab(s, page, c->freelist); | |
2294 | c->page = NULL; | |
2295 | c->freelist = NULL; | |
2296 | goto new_slab; | |
2297 | } | |
fc59c053 | 2298 | } |
6446faa2 | 2299 | |
072bb0aa MG |
2300 | /* |
2301 | * By rights, we should be searching for a slab page that was | |
2302 | * PFMEMALLOC but right now, we are losing the pfmemalloc | |
2303 | * information when the page leaves the per-cpu allocator | |
2304 | */ | |
2305 | if (unlikely(!pfmemalloc_match(page, gfpflags))) { | |
2306 | deactivate_slab(s, page, c->freelist); | |
2307 | c->page = NULL; | |
2308 | c->freelist = NULL; | |
2309 | goto new_slab; | |
2310 | } | |
2311 | ||
73736e03 | 2312 | /* must check again c->freelist in case of cpu migration or IRQ */ |
6faa6833 CL |
2313 | freelist = c->freelist; |
2314 | if (freelist) | |
73736e03 | 2315 | goto load_freelist; |
03e404af | 2316 | |
f6e7def7 | 2317 | freelist = get_freelist(s, page); |
6446faa2 | 2318 | |
6faa6833 | 2319 | if (!freelist) { |
03e404af CL |
2320 | c->page = NULL; |
2321 | stat(s, DEACTIVATE_BYPASS); | |
fc59c053 | 2322 | goto new_slab; |
03e404af | 2323 | } |
6446faa2 | 2324 | |
84e554e6 | 2325 | stat(s, ALLOC_REFILL); |
6446faa2 | 2326 | |
894b8788 | 2327 | load_freelist: |
507effea CL |
2328 | /* |
2329 | * freelist is pointing to the list of objects to be used. | |
2330 | * page is pointing to the page from which the objects are obtained. | |
2331 | * That page must be frozen for per cpu allocations to work. | |
2332 | */ | |
a0132ac0 | 2333 | VM_BUG_ON(!c->page->frozen); |
6faa6833 | 2334 | c->freelist = get_freepointer(s, freelist); |
8a5ec0ba CL |
2335 | c->tid = next_tid(c->tid); |
2336 | local_irq_restore(flags); | |
6faa6833 | 2337 | return freelist; |
81819f0f | 2338 | |
81819f0f | 2339 | new_slab: |
2cfb7455 | 2340 | |
49e22585 | 2341 | if (c->partial) { |
f6e7def7 CL |
2342 | page = c->page = c->partial; |
2343 | c->partial = page->next; | |
49e22585 CL |
2344 | stat(s, CPU_PARTIAL_ALLOC); |
2345 | c->freelist = NULL; | |
2346 | goto redo; | |
81819f0f CL |
2347 | } |
2348 | ||
188fd063 | 2349 | freelist = new_slab_objects(s, gfpflags, node, &c); |
01ad8a7b | 2350 | |
f4697436 | 2351 | if (unlikely(!freelist)) { |
9a02d699 | 2352 | slab_out_of_memory(s, gfpflags, node); |
f4697436 CL |
2353 | local_irq_restore(flags); |
2354 | return NULL; | |
81819f0f | 2355 | } |
2cfb7455 | 2356 | |
f6e7def7 | 2357 | page = c->page; |
5091b74a | 2358 | if (likely(!kmem_cache_debug(s) && pfmemalloc_match(page, gfpflags))) |
4b6f0750 | 2359 | goto load_freelist; |
2cfb7455 | 2360 | |
497b66f2 | 2361 | /* Only entered in the debug case */ |
d0e0ac97 CG |
2362 | if (kmem_cache_debug(s) && |
2363 | !alloc_debug_processing(s, page, freelist, addr)) | |
497b66f2 | 2364 | goto new_slab; /* Slab failed checks. Next slab needed */ |
894b8788 | 2365 | |
f6e7def7 | 2366 | deactivate_slab(s, page, get_freepointer(s, freelist)); |
c17dda40 CL |
2367 | c->page = NULL; |
2368 | c->freelist = NULL; | |
a71ae47a | 2369 | local_irq_restore(flags); |
6faa6833 | 2370 | return freelist; |
894b8788 CL |
2371 | } |
2372 | ||
2373 | /* | |
2374 | * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) | |
2375 | * have the fastpath folded into their functions. So no function call | |
2376 | * overhead for requests that can be satisfied on the fastpath. | |
2377 | * | |
2378 | * The fastpath works by first checking if the lockless freelist can be used. | |
2379 | * If not then __slab_alloc is called for slow processing. | |
2380 | * | |
2381 | * Otherwise we can simply pick the next object from the lockless free list. | |
2382 | */ | |
2b847c3c | 2383 | static __always_inline void *slab_alloc_node(struct kmem_cache *s, |
ce71e27c | 2384 | gfp_t gfpflags, int node, unsigned long addr) |
894b8788 | 2385 | { |
894b8788 | 2386 | void **object; |
dfb4f096 | 2387 | struct kmem_cache_cpu *c; |
57d437d2 | 2388 | struct page *page; |
8a5ec0ba | 2389 | unsigned long tid; |
1f84260c | 2390 | |
8135be5a VD |
2391 | s = slab_pre_alloc_hook(s, gfpflags); |
2392 | if (!s) | |
773ff60e | 2393 | return NULL; |
8a5ec0ba | 2394 | redo: |
8a5ec0ba CL |
2395 | /* |
2396 | * Must read kmem_cache cpu data via this cpu ptr. Preemption is | |
2397 | * enabled. We may switch back and forth between cpus while | |
2398 | * reading from one cpu area. That does not matter as long | |
2399 | * as we end up on the original cpu again when doing the cmpxchg. | |
7cccd80b | 2400 | * |
9aabf810 JK |
2401 | * We should guarantee that tid and kmem_cache are retrieved on |
2402 | * the same cpu. It could be different if CONFIG_PREEMPT so we need | |
2403 | * to check if it is matched or not. | |
8a5ec0ba | 2404 | */ |
9aabf810 JK |
2405 | do { |
2406 | tid = this_cpu_read(s->cpu_slab->tid); | |
2407 | c = raw_cpu_ptr(s->cpu_slab); | |
2408 | } while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid)); | |
2409 | ||
2410 | /* | |
2411 | * Irqless object alloc/free algorithm used here depends on sequence | |
2412 | * of fetching cpu_slab's data. tid should be fetched before anything | |
2413 | * on c to guarantee that object and page associated with previous tid | |
2414 | * won't be used with current tid. If we fetch tid first, object and | |
2415 | * page could be one associated with next tid and our alloc/free | |
2416 | * request will be failed. In this case, we will retry. So, no problem. | |
2417 | */ | |
2418 | barrier(); | |
8a5ec0ba | 2419 | |
8a5ec0ba CL |
2420 | /* |
2421 | * The transaction ids are globally unique per cpu and per operation on | |
2422 | * a per cpu queue. Thus they can be guarantee that the cmpxchg_double | |
2423 | * occurs on the right processor and that there was no operation on the | |
2424 | * linked list in between. | |
2425 | */ | |
8a5ec0ba | 2426 | |
9dfc6e68 | 2427 | object = c->freelist; |
57d437d2 | 2428 | page = c->page; |
8eae1492 | 2429 | if (unlikely(!object || !node_match(page, node))) { |
dfb4f096 | 2430 | object = __slab_alloc(s, gfpflags, node, addr, c); |
8eae1492 DH |
2431 | stat(s, ALLOC_SLOWPATH); |
2432 | } else { | |
0ad9500e ED |
2433 | void *next_object = get_freepointer_safe(s, object); |
2434 | ||
8a5ec0ba | 2435 | /* |
25985edc | 2436 | * The cmpxchg will only match if there was no additional |
8a5ec0ba CL |
2437 | * operation and if we are on the right processor. |
2438 | * | |
d0e0ac97 CG |
2439 | * The cmpxchg does the following atomically (without lock |
2440 | * semantics!) | |
8a5ec0ba CL |
2441 | * 1. Relocate first pointer to the current per cpu area. |
2442 | * 2. Verify that tid and freelist have not been changed | |
2443 | * 3. If they were not changed replace tid and freelist | |
2444 | * | |
d0e0ac97 CG |
2445 | * Since this is without lock semantics the protection is only |
2446 | * against code executing on this cpu *not* from access by | |
2447 | * other cpus. | |
8a5ec0ba | 2448 | */ |
933393f5 | 2449 | if (unlikely(!this_cpu_cmpxchg_double( |
8a5ec0ba CL |
2450 | s->cpu_slab->freelist, s->cpu_slab->tid, |
2451 | object, tid, | |
0ad9500e | 2452 | next_object, next_tid(tid)))) { |
8a5ec0ba CL |
2453 | |
2454 | note_cmpxchg_failure("slab_alloc", s, tid); | |
2455 | goto redo; | |
2456 | } | |
0ad9500e | 2457 | prefetch_freepointer(s, next_object); |
84e554e6 | 2458 | stat(s, ALLOC_FASTPATH); |
894b8788 | 2459 | } |
8a5ec0ba | 2460 | |
74e2134f | 2461 | if (unlikely(gfpflags & __GFP_ZERO) && object) |
3b0efdfa | 2462 | memset(object, 0, s->object_size); |
d07dbea4 | 2463 | |
c016b0bd | 2464 | slab_post_alloc_hook(s, gfpflags, object); |
5a896d9e | 2465 | |
894b8788 | 2466 | return object; |
81819f0f CL |
2467 | } |
2468 | ||
2b847c3c EG |
2469 | static __always_inline void *slab_alloc(struct kmem_cache *s, |
2470 | gfp_t gfpflags, unsigned long addr) | |
2471 | { | |
2472 | return slab_alloc_node(s, gfpflags, NUMA_NO_NODE, addr); | |
2473 | } | |
2474 | ||
81819f0f CL |
2475 | void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) |
2476 | { | |
2b847c3c | 2477 | void *ret = slab_alloc(s, gfpflags, _RET_IP_); |
5b882be4 | 2478 | |
d0e0ac97 CG |
2479 | trace_kmem_cache_alloc(_RET_IP_, ret, s->object_size, |
2480 | s->size, gfpflags); | |
5b882be4 EGM |
2481 | |
2482 | return ret; | |
81819f0f CL |
2483 | } |
2484 | EXPORT_SYMBOL(kmem_cache_alloc); | |
2485 | ||
0f24f128 | 2486 | #ifdef CONFIG_TRACING |
4a92379b RK |
2487 | void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) |
2488 | { | |
2b847c3c | 2489 | void *ret = slab_alloc(s, gfpflags, _RET_IP_); |
4a92379b RK |
2490 | trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags); |
2491 | return ret; | |
2492 | } | |
2493 | EXPORT_SYMBOL(kmem_cache_alloc_trace); | |
5b882be4 EGM |
2494 | #endif |
2495 | ||
81819f0f CL |
2496 | #ifdef CONFIG_NUMA |
2497 | void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) | |
2498 | { | |
2b847c3c | 2499 | void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_); |
5b882be4 | 2500 | |
ca2b84cb | 2501 | trace_kmem_cache_alloc_node(_RET_IP_, ret, |
3b0efdfa | 2502 | s->object_size, s->size, gfpflags, node); |
5b882be4 EGM |
2503 | |
2504 | return ret; | |
81819f0f CL |
2505 | } |
2506 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
81819f0f | 2507 | |
0f24f128 | 2508 | #ifdef CONFIG_TRACING |
4a92379b | 2509 | void *kmem_cache_alloc_node_trace(struct kmem_cache *s, |
5b882be4 | 2510 | gfp_t gfpflags, |
4a92379b | 2511 | int node, size_t size) |
5b882be4 | 2512 | { |
2b847c3c | 2513 | void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_); |
4a92379b RK |
2514 | |
2515 | trace_kmalloc_node(_RET_IP_, ret, | |
2516 | size, s->size, gfpflags, node); | |
2517 | return ret; | |
5b882be4 | 2518 | } |
4a92379b | 2519 | EXPORT_SYMBOL(kmem_cache_alloc_node_trace); |
5b882be4 | 2520 | #endif |
5d1f57e4 | 2521 | #endif |
5b882be4 | 2522 | |
81819f0f | 2523 | /* |
94e4d712 | 2524 | * Slow path handling. This may still be called frequently since objects |
894b8788 | 2525 | * have a longer lifetime than the cpu slabs in most processing loads. |
81819f0f | 2526 | * |
894b8788 CL |
2527 | * So we still attempt to reduce cache line usage. Just take the slab |
2528 | * lock and free the item. If there is no additional partial page | |
2529 | * handling required then we can return immediately. | |
81819f0f | 2530 | */ |
894b8788 | 2531 | static void __slab_free(struct kmem_cache *s, struct page *page, |
ff12059e | 2532 | void *x, unsigned long addr) |
81819f0f CL |
2533 | { |
2534 | void *prior; | |
2535 | void **object = (void *)x; | |
2cfb7455 | 2536 | int was_frozen; |
2cfb7455 CL |
2537 | struct page new; |
2538 | unsigned long counters; | |
2539 | struct kmem_cache_node *n = NULL; | |
61728d1e | 2540 | unsigned long uninitialized_var(flags); |
81819f0f | 2541 | |
8a5ec0ba | 2542 | stat(s, FREE_SLOWPATH); |
81819f0f | 2543 | |
19c7ff9e CL |
2544 | if (kmem_cache_debug(s) && |
2545 | !(n = free_debug_processing(s, page, x, addr, &flags))) | |
80f08c19 | 2546 | return; |
6446faa2 | 2547 | |
2cfb7455 | 2548 | do { |
837d678d JK |
2549 | if (unlikely(n)) { |
2550 | spin_unlock_irqrestore(&n->list_lock, flags); | |
2551 | n = NULL; | |
2552 | } | |
2cfb7455 CL |
2553 | prior = page->freelist; |
2554 | counters = page->counters; | |
2555 | set_freepointer(s, object, prior); | |
2556 | new.counters = counters; | |
2557 | was_frozen = new.frozen; | |
2558 | new.inuse--; | |
837d678d | 2559 | if ((!new.inuse || !prior) && !was_frozen) { |
49e22585 | 2560 | |
c65c1877 | 2561 | if (kmem_cache_has_cpu_partial(s) && !prior) { |
49e22585 CL |
2562 | |
2563 | /* | |
d0e0ac97 CG |
2564 | * Slab was on no list before and will be |
2565 | * partially empty | |
2566 | * We can defer the list move and instead | |
2567 | * freeze it. | |
49e22585 CL |
2568 | */ |
2569 | new.frozen = 1; | |
2570 | ||
c65c1877 | 2571 | } else { /* Needs to be taken off a list */ |
49e22585 | 2572 | |
b455def2 | 2573 | n = get_node(s, page_to_nid(page)); |
49e22585 CL |
2574 | /* |
2575 | * Speculatively acquire the list_lock. | |
2576 | * If the cmpxchg does not succeed then we may | |
2577 | * drop the list_lock without any processing. | |
2578 | * | |
2579 | * Otherwise the list_lock will synchronize with | |
2580 | * other processors updating the list of slabs. | |
2581 | */ | |
2582 | spin_lock_irqsave(&n->list_lock, flags); | |
2583 | ||
2584 | } | |
2cfb7455 | 2585 | } |
81819f0f | 2586 | |
2cfb7455 CL |
2587 | } while (!cmpxchg_double_slab(s, page, |
2588 | prior, counters, | |
2589 | object, new.counters, | |
2590 | "__slab_free")); | |
81819f0f | 2591 | |
2cfb7455 | 2592 | if (likely(!n)) { |
49e22585 CL |
2593 | |
2594 | /* | |
2595 | * If we just froze the page then put it onto the | |
2596 | * per cpu partial list. | |
2597 | */ | |
8028dcea | 2598 | if (new.frozen && !was_frozen) { |
49e22585 | 2599 | put_cpu_partial(s, page, 1); |
8028dcea AS |
2600 | stat(s, CPU_PARTIAL_FREE); |
2601 | } | |
49e22585 | 2602 | /* |
2cfb7455 CL |
2603 | * The list lock was not taken therefore no list |
2604 | * activity can be necessary. | |
2605 | */ | |
b455def2 L |
2606 | if (was_frozen) |
2607 | stat(s, FREE_FROZEN); | |
2608 | return; | |
2609 | } | |
81819f0f | 2610 | |
8a5b20ae | 2611 | if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) |
837d678d JK |
2612 | goto slab_empty; |
2613 | ||
81819f0f | 2614 | /* |
837d678d JK |
2615 | * Objects left in the slab. If it was not on the partial list before |
2616 | * then add it. | |
81819f0f | 2617 | */ |
345c905d JK |
2618 | if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { |
2619 | if (kmem_cache_debug(s)) | |
c65c1877 | 2620 | remove_full(s, n, page); |
837d678d JK |
2621 | add_partial(n, page, DEACTIVATE_TO_TAIL); |
2622 | stat(s, FREE_ADD_PARTIAL); | |
8ff12cfc | 2623 | } |
80f08c19 | 2624 | spin_unlock_irqrestore(&n->list_lock, flags); |
81819f0f CL |
2625 | return; |
2626 | ||
2627 | slab_empty: | |
a973e9dd | 2628 | if (prior) { |
81819f0f | 2629 | /* |
6fbabb20 | 2630 | * Slab on the partial list. |
81819f0f | 2631 | */ |
5cc6eee8 | 2632 | remove_partial(n, page); |
84e554e6 | 2633 | stat(s, FREE_REMOVE_PARTIAL); |
c65c1877 | 2634 | } else { |
6fbabb20 | 2635 | /* Slab must be on the full list */ |
c65c1877 PZ |
2636 | remove_full(s, n, page); |
2637 | } | |
2cfb7455 | 2638 | |
80f08c19 | 2639 | spin_unlock_irqrestore(&n->list_lock, flags); |
84e554e6 | 2640 | stat(s, FREE_SLAB); |
81819f0f | 2641 | discard_slab(s, page); |
81819f0f CL |
2642 | } |
2643 | ||
894b8788 CL |
2644 | /* |
2645 | * Fastpath with forced inlining to produce a kfree and kmem_cache_free that | |
2646 | * can perform fastpath freeing without additional function calls. | |
2647 | * | |
2648 | * The fastpath is only possible if we are freeing to the current cpu slab | |
2649 | * of this processor. This typically the case if we have just allocated | |
2650 | * the item before. | |
2651 | * | |
2652 | * If fastpath is not possible then fall back to __slab_free where we deal | |
2653 | * with all sorts of special processing. | |
2654 | */ | |
06428780 | 2655 | static __always_inline void slab_free(struct kmem_cache *s, |
ce71e27c | 2656 | struct page *page, void *x, unsigned long addr) |
894b8788 CL |
2657 | { |
2658 | void **object = (void *)x; | |
dfb4f096 | 2659 | struct kmem_cache_cpu *c; |
8a5ec0ba | 2660 | unsigned long tid; |
1f84260c | 2661 | |
c016b0bd CL |
2662 | slab_free_hook(s, x); |
2663 | ||
8a5ec0ba CL |
2664 | redo: |
2665 | /* | |
2666 | * Determine the currently cpus per cpu slab. | |
2667 | * The cpu may change afterward. However that does not matter since | |
2668 | * data is retrieved via this pointer. If we are on the same cpu | |
2669 | * during the cmpxchg then the free will succedd. | |
2670 | */ | |
9aabf810 JK |
2671 | do { |
2672 | tid = this_cpu_read(s->cpu_slab->tid); | |
2673 | c = raw_cpu_ptr(s->cpu_slab); | |
2674 | } while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid)); | |
c016b0bd | 2675 | |
9aabf810 JK |
2676 | /* Same with comment on barrier() in slab_alloc_node() */ |
2677 | barrier(); | |
c016b0bd | 2678 | |
442b06bc | 2679 | if (likely(page == c->page)) { |
ff12059e | 2680 | set_freepointer(s, object, c->freelist); |
8a5ec0ba | 2681 | |
933393f5 | 2682 | if (unlikely(!this_cpu_cmpxchg_double( |
8a5ec0ba CL |
2683 | s->cpu_slab->freelist, s->cpu_slab->tid, |
2684 | c->freelist, tid, | |
2685 | object, next_tid(tid)))) { | |
2686 | ||
2687 | note_cmpxchg_failure("slab_free", s, tid); | |
2688 | goto redo; | |
2689 | } | |
84e554e6 | 2690 | stat(s, FREE_FASTPATH); |
894b8788 | 2691 | } else |
ff12059e | 2692 | __slab_free(s, page, x, addr); |
894b8788 | 2693 | |
894b8788 CL |
2694 | } |
2695 | ||
81819f0f CL |
2696 | void kmem_cache_free(struct kmem_cache *s, void *x) |
2697 | { | |
b9ce5ef4 GC |
2698 | s = cache_from_obj(s, x); |
2699 | if (!s) | |
79576102 | 2700 | return; |
b9ce5ef4 | 2701 | slab_free(s, virt_to_head_page(x), x, _RET_IP_); |
ca2b84cb | 2702 | trace_kmem_cache_free(_RET_IP_, x); |
81819f0f CL |
2703 | } |
2704 | EXPORT_SYMBOL(kmem_cache_free); | |
2705 | ||
81819f0f | 2706 | /* |
672bba3a CL |
2707 | * Object placement in a slab is made very easy because we always start at |
2708 | * offset 0. If we tune the size of the object to the alignment then we can | |
2709 | * get the required alignment by putting one properly sized object after | |
2710 | * another. | |
81819f0f CL |
2711 | * |
2712 | * Notice that the allocation order determines the sizes of the per cpu | |
2713 | * caches. Each processor has always one slab available for allocations. | |
2714 | * Increasing the allocation order reduces the number of times that slabs | |
672bba3a | 2715 | * must be moved on and off the partial lists and is therefore a factor in |
81819f0f | 2716 | * locking overhead. |
81819f0f CL |
2717 | */ |
2718 | ||
2719 | /* | |
2720 | * Mininum / Maximum order of slab pages. This influences locking overhead | |
2721 | * and slab fragmentation. A higher order reduces the number of partial slabs | |
2722 | * and increases the number of allocations possible without having to | |
2723 | * take the list_lock. | |
2724 | */ | |
2725 | static int slub_min_order; | |
114e9e89 | 2726 | static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER; |
9b2cd506 | 2727 | static int slub_min_objects; |
81819f0f | 2728 | |
81819f0f CL |
2729 | /* |
2730 | * Calculate the order of allocation given an slab object size. | |
2731 | * | |
672bba3a CL |
2732 | * The order of allocation has significant impact on performance and other |
2733 | * system components. Generally order 0 allocations should be preferred since | |
2734 | * order 0 does not cause fragmentation in the page allocator. Larger objects | |
2735 | * be problematic to put into order 0 slabs because there may be too much | |
c124f5b5 | 2736 | * unused space left. We go to a higher order if more than 1/16th of the slab |
672bba3a CL |
2737 | * would be wasted. |
2738 | * | |
2739 | * In order to reach satisfactory performance we must ensure that a minimum | |
2740 | * number of objects is in one slab. Otherwise we may generate too much | |
2741 | * activity on the partial lists which requires taking the list_lock. This is | |
2742 | * less a concern for large slabs though which are rarely used. | |
81819f0f | 2743 | * |
672bba3a CL |
2744 | * slub_max_order specifies the order where we begin to stop considering the |
2745 | * number of objects in a slab as critical. If we reach slub_max_order then | |
2746 | * we try to keep the page order as low as possible. So we accept more waste | |
2747 | * of space in favor of a small page order. | |
81819f0f | 2748 | * |
672bba3a CL |
2749 | * Higher order allocations also allow the placement of more objects in a |
2750 | * slab and thereby reduce object handling overhead. If the user has | |
2751 | * requested a higher mininum order then we start with that one instead of | |
2752 | * the smallest order which will fit the object. | |
81819f0f | 2753 | */ |
5e6d444e | 2754 | static inline int slab_order(int size, int min_objects, |
ab9a0f19 | 2755 | int max_order, int fract_leftover, int reserved) |
81819f0f CL |
2756 | { |
2757 | int order; | |
2758 | int rem; | |
6300ea75 | 2759 | int min_order = slub_min_order; |
81819f0f | 2760 | |
ab9a0f19 | 2761 | if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE) |
210b5c06 | 2762 | return get_order(size * MAX_OBJS_PER_PAGE) - 1; |
39b26464 | 2763 | |
6300ea75 | 2764 | for (order = max(min_order, |
5e6d444e CL |
2765 | fls(min_objects * size - 1) - PAGE_SHIFT); |
2766 | order <= max_order; order++) { | |
81819f0f | 2767 | |
5e6d444e | 2768 | unsigned long slab_size = PAGE_SIZE << order; |
81819f0f | 2769 | |
ab9a0f19 | 2770 | if (slab_size < min_objects * size + reserved) |
81819f0f CL |
2771 | continue; |
2772 | ||
ab9a0f19 | 2773 | rem = (slab_size - reserved) % size; |
81819f0f | 2774 | |
5e6d444e | 2775 | if (rem <= slab_size / fract_leftover) |
81819f0f CL |
2776 | break; |
2777 | ||
2778 | } | |
672bba3a | 2779 | |
81819f0f CL |
2780 | return order; |
2781 | } | |
2782 | ||
ab9a0f19 | 2783 | static inline int calculate_order(int size, int reserved) |
5e6d444e CL |
2784 | { |
2785 | int order; | |
2786 | int min_objects; | |
2787 | int fraction; | |
e8120ff1 | 2788 | int max_objects; |
5e6d444e CL |
2789 | |
2790 | /* | |
2791 | * Attempt to find best configuration for a slab. This | |
2792 | * works by first attempting to generate a layout with | |
2793 | * the best configuration and backing off gradually. | |
2794 | * | |
2795 | * First we reduce the acceptable waste in a slab. Then | |
2796 | * we reduce the minimum objects required in a slab. | |
2797 | */ | |
2798 | min_objects = slub_min_objects; | |
9b2cd506 CL |
2799 | if (!min_objects) |
2800 | min_objects = 4 * (fls(nr_cpu_ids) + 1); | |
ab9a0f19 | 2801 | max_objects = order_objects(slub_max_order, size, reserved); |
e8120ff1 ZY |
2802 | min_objects = min(min_objects, max_objects); |
2803 | ||
5e6d444e | 2804 | while (min_objects > 1) { |
c124f5b5 | 2805 | fraction = 16; |
5e6d444e CL |
2806 | while (fraction >= 4) { |
2807 | order = slab_order(size, min_objects, | |
ab9a0f19 | 2808 | slub_max_order, fraction, reserved); |
5e6d444e CL |
2809 | if (order <= slub_max_order) |
2810 | return order; | |
2811 | fraction /= 2; | |
2812 | } | |
5086c389 | 2813 | min_objects--; |
5e6d444e CL |
2814 | } |
2815 | ||
2816 | /* | |
2817 | * We were unable to place multiple objects in a slab. Now | |
2818 | * lets see if we can place a single object there. | |
2819 | */ | |
ab9a0f19 | 2820 | order = slab_order(size, 1, slub_max_order, 1, reserved); |
5e6d444e CL |
2821 | if (order <= slub_max_order) |
2822 | return order; | |
2823 | ||
2824 | /* | |
2825 | * Doh this slab cannot be placed using slub_max_order. | |
2826 | */ | |
ab9a0f19 | 2827 | order = slab_order(size, 1, MAX_ORDER, 1, reserved); |
818cf590 | 2828 | if (order < MAX_ORDER) |
5e6d444e CL |
2829 | return order; |
2830 | return -ENOSYS; | |
2831 | } | |
2832 | ||
5595cffc | 2833 | static void |
4053497d | 2834 | init_kmem_cache_node(struct kmem_cache_node *n) |
81819f0f CL |
2835 | { |
2836 | n->nr_partial = 0; | |
81819f0f CL |
2837 | spin_lock_init(&n->list_lock); |
2838 | INIT_LIST_HEAD(&n->partial); | |
8ab1372f | 2839 | #ifdef CONFIG_SLUB_DEBUG |
0f389ec6 | 2840 | atomic_long_set(&n->nr_slabs, 0); |
02b71b70 | 2841 | atomic_long_set(&n->total_objects, 0); |
643b1138 | 2842 | INIT_LIST_HEAD(&n->full); |
8ab1372f | 2843 | #endif |
81819f0f CL |
2844 | } |
2845 | ||
55136592 | 2846 | static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) |
4c93c355 | 2847 | { |
6c182dc0 | 2848 | BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < |
95a05b42 | 2849 | KMALLOC_SHIFT_HIGH * sizeof(struct kmem_cache_cpu)); |
4c93c355 | 2850 | |
8a5ec0ba | 2851 | /* |
d4d84fef CM |
2852 | * Must align to double word boundary for the double cmpxchg |
2853 | * instructions to work; see __pcpu_double_call_return_bool(). | |
8a5ec0ba | 2854 | */ |
d4d84fef CM |
2855 | s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), |
2856 | 2 * sizeof(void *)); | |
8a5ec0ba CL |
2857 | |
2858 | if (!s->cpu_slab) | |
2859 | return 0; | |
2860 | ||
2861 | init_kmem_cache_cpus(s); | |
4c93c355 | 2862 | |
8a5ec0ba | 2863 | return 1; |
4c93c355 | 2864 | } |
4c93c355 | 2865 | |
51df1142 CL |
2866 | static struct kmem_cache *kmem_cache_node; |
2867 | ||
81819f0f CL |
2868 | /* |
2869 | * No kmalloc_node yet so do it by hand. We know that this is the first | |
2870 | * slab on the node for this slabcache. There are no concurrent accesses | |
2871 | * possible. | |
2872 | * | |
721ae22a ZYW |
2873 | * Note that this function only works on the kmem_cache_node |
2874 | * when allocating for the kmem_cache_node. This is used for bootstrapping | |
4c93c355 | 2875 | * memory on a fresh node that has no slab structures yet. |
81819f0f | 2876 | */ |
55136592 | 2877 | static void early_kmem_cache_node_alloc(int node) |
81819f0f CL |
2878 | { |
2879 | struct page *page; | |
2880 | struct kmem_cache_node *n; | |
2881 | ||
51df1142 | 2882 | BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); |
81819f0f | 2883 | |
51df1142 | 2884 | page = new_slab(kmem_cache_node, GFP_NOWAIT, node); |
81819f0f CL |
2885 | |
2886 | BUG_ON(!page); | |
a2f92ee7 | 2887 | if (page_to_nid(page) != node) { |
f9f58285 FF |
2888 | pr_err("SLUB: Unable to allocate memory from node %d\n", node); |
2889 | pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); | |
a2f92ee7 CL |
2890 | } |
2891 | ||
81819f0f CL |
2892 | n = page->freelist; |
2893 | BUG_ON(!n); | |
51df1142 | 2894 | page->freelist = get_freepointer(kmem_cache_node, n); |
e6e82ea1 | 2895 | page->inuse = 1; |
8cb0a506 | 2896 | page->frozen = 0; |
51df1142 | 2897 | kmem_cache_node->node[node] = n; |
8ab1372f | 2898 | #ifdef CONFIG_SLUB_DEBUG |
f7cb1933 | 2899 | init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); |
51df1142 | 2900 | init_tracking(kmem_cache_node, n); |
8ab1372f | 2901 | #endif |
4053497d | 2902 | init_kmem_cache_node(n); |
51df1142 | 2903 | inc_slabs_node(kmem_cache_node, node, page->objects); |
6446faa2 | 2904 | |
67b6c900 | 2905 | /* |
1e4dd946 SR |
2906 | * No locks need to be taken here as it has just been |
2907 | * initialized and there is no concurrent access. | |
67b6c900 | 2908 | */ |
1e4dd946 | 2909 | __add_partial(n, page, DEACTIVATE_TO_HEAD); |
81819f0f CL |
2910 | } |
2911 | ||
2912 | static void free_kmem_cache_nodes(struct kmem_cache *s) | |
2913 | { | |
2914 | int node; | |
fa45dc25 | 2915 | struct kmem_cache_node *n; |
81819f0f | 2916 | |
fa45dc25 CL |
2917 | for_each_kmem_cache_node(s, node, n) { |
2918 | kmem_cache_free(kmem_cache_node, n); | |
81819f0f CL |
2919 | s->node[node] = NULL; |
2920 | } | |
2921 | } | |
2922 | ||
55136592 | 2923 | static int init_kmem_cache_nodes(struct kmem_cache *s) |
81819f0f CL |
2924 | { |
2925 | int node; | |
81819f0f | 2926 | |
f64dc58c | 2927 | for_each_node_state(node, N_NORMAL_MEMORY) { |
81819f0f CL |
2928 | struct kmem_cache_node *n; |
2929 | ||
73367bd8 | 2930 | if (slab_state == DOWN) { |
55136592 | 2931 | early_kmem_cache_node_alloc(node); |
73367bd8 AD |
2932 | continue; |
2933 | } | |
51df1142 | 2934 | n = kmem_cache_alloc_node(kmem_cache_node, |
55136592 | 2935 | GFP_KERNEL, node); |
81819f0f | 2936 | |
73367bd8 AD |
2937 | if (!n) { |
2938 | free_kmem_cache_nodes(s); | |
2939 | return 0; | |
81819f0f | 2940 | } |
73367bd8 | 2941 | |
81819f0f | 2942 | s->node[node] = n; |
4053497d | 2943 | init_kmem_cache_node(n); |
81819f0f CL |
2944 | } |
2945 | return 1; | |
2946 | } | |
81819f0f | 2947 | |
c0bdb232 | 2948 | static void set_min_partial(struct kmem_cache *s, unsigned long min) |
3b89d7d8 DR |
2949 | { |
2950 | if (min < MIN_PARTIAL) | |
2951 | min = MIN_PARTIAL; | |
2952 | else if (min > MAX_PARTIAL) | |
2953 | min = MAX_PARTIAL; | |
2954 | s->min_partial = min; | |
2955 | } | |
2956 | ||
81819f0f CL |
2957 | /* |
2958 | * calculate_sizes() determines the order and the distribution of data within | |
2959 | * a slab object. | |
2960 | */ | |
06b285dc | 2961 | static int calculate_sizes(struct kmem_cache *s, int forced_order) |
81819f0f CL |
2962 | { |
2963 | unsigned long flags = s->flags; | |
3b0efdfa | 2964 | unsigned long size = s->object_size; |
834f3d11 | 2965 | int order; |
81819f0f | 2966 | |
d8b42bf5 CL |
2967 | /* |
2968 | * Round up object size to the next word boundary. We can only | |
2969 | * place the free pointer at word boundaries and this determines | |
2970 | * the possible location of the free pointer. | |
2971 | */ | |
2972 | size = ALIGN(size, sizeof(void *)); | |
2973 | ||
2974 | #ifdef CONFIG_SLUB_DEBUG | |
81819f0f CL |
2975 | /* |
2976 | * Determine if we can poison the object itself. If the user of | |
2977 | * the slab may touch the object after free or before allocation | |
2978 | * then we should never poison the object itself. | |
2979 | */ | |
2980 | if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) && | |
c59def9f | 2981 | !s->ctor) |
81819f0f CL |
2982 | s->flags |= __OBJECT_POISON; |
2983 | else | |
2984 | s->flags &= ~__OBJECT_POISON; | |
2985 | ||
81819f0f CL |
2986 | |
2987 | /* | |
672bba3a | 2988 | * If we are Redzoning then check if there is some space between the |
81819f0f | 2989 | * end of the object and the free pointer. If not then add an |
672bba3a | 2990 | * additional word to have some bytes to store Redzone information. |
81819f0f | 2991 | */ |
3b0efdfa | 2992 | if ((flags & SLAB_RED_ZONE) && size == s->object_size) |
81819f0f | 2993 | size += sizeof(void *); |
41ecc55b | 2994 | #endif |
81819f0f CL |
2995 | |
2996 | /* | |
672bba3a CL |
2997 | * With that we have determined the number of bytes in actual use |
2998 | * by the object. This is the potential offset to the free pointer. | |
81819f0f CL |
2999 | */ |
3000 | s->inuse = size; | |
3001 | ||
3002 | if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) || | |
c59def9f | 3003 | s->ctor)) { |
81819f0f CL |
3004 | /* |
3005 | * Relocate free pointer after the object if it is not | |
3006 | * permitted to overwrite the first word of the object on | |
3007 | * kmem_cache_free. | |
3008 | * | |
3009 | * This is the case if we do RCU, have a constructor or | |
3010 | * destructor or are poisoning the objects. | |
3011 | */ | |
3012 | s->offset = size; | |
3013 | size += sizeof(void *); | |
3014 | } | |
3015 | ||
c12b3c62 | 3016 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
3017 | if (flags & SLAB_STORE_USER) |
3018 | /* | |
3019 | * Need to store information about allocs and frees after | |
3020 | * the object. | |
3021 | */ | |
3022 | size += 2 * sizeof(struct track); | |
3023 | ||
be7b3fbc | 3024 | if (flags & SLAB_RED_ZONE) |
81819f0f CL |
3025 | /* |
3026 | * Add some empty padding so that we can catch | |
3027 | * overwrites from earlier objects rather than let | |
3028 | * tracking information or the free pointer be | |
0211a9c8 | 3029 | * corrupted if a user writes before the start |
81819f0f CL |
3030 | * of the object. |
3031 | */ | |
3032 | size += sizeof(void *); | |
41ecc55b | 3033 | #endif |
672bba3a | 3034 | |
81819f0f CL |
3035 | /* |
3036 | * SLUB stores one object immediately after another beginning from | |
3037 | * offset 0. In order to align the objects we have to simply size | |
3038 | * each object to conform to the alignment. | |
3039 | */ | |
45906855 | 3040 | size = ALIGN(size, s->align); |
81819f0f | 3041 | s->size = size; |
06b285dc CL |
3042 | if (forced_order >= 0) |
3043 | order = forced_order; | |
3044 | else | |
ab9a0f19 | 3045 | order = calculate_order(size, s->reserved); |
81819f0f | 3046 | |
834f3d11 | 3047 | if (order < 0) |
81819f0f CL |
3048 | return 0; |
3049 | ||
b7a49f0d | 3050 | s->allocflags = 0; |
834f3d11 | 3051 | if (order) |
b7a49f0d CL |
3052 | s->allocflags |= __GFP_COMP; |
3053 | ||
3054 | if (s->flags & SLAB_CACHE_DMA) | |
2c59dd65 | 3055 | s->allocflags |= GFP_DMA; |
b7a49f0d CL |
3056 | |
3057 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
3058 | s->allocflags |= __GFP_RECLAIMABLE; | |
3059 | ||
81819f0f CL |
3060 | /* |
3061 | * Determine the number of objects per slab | |
3062 | */ | |
ab9a0f19 LJ |
3063 | s->oo = oo_make(order, size, s->reserved); |
3064 | s->min = oo_make(get_order(size), size, s->reserved); | |
205ab99d CL |
3065 | if (oo_objects(s->oo) > oo_objects(s->max)) |
3066 | s->max = s->oo; | |
81819f0f | 3067 | |
834f3d11 | 3068 | return !!oo_objects(s->oo); |
81819f0f CL |
3069 | } |
3070 | ||
8a13a4cc | 3071 | static int kmem_cache_open(struct kmem_cache *s, unsigned long flags) |
81819f0f | 3072 | { |
8a13a4cc | 3073 | s->flags = kmem_cache_flags(s->size, flags, s->name, s->ctor); |
ab9a0f19 | 3074 | s->reserved = 0; |
81819f0f | 3075 | |
da9a638c LJ |
3076 | if (need_reserve_slab_rcu && (s->flags & SLAB_DESTROY_BY_RCU)) |
3077 | s->reserved = sizeof(struct rcu_head); | |
81819f0f | 3078 | |
06b285dc | 3079 | if (!calculate_sizes(s, -1)) |
81819f0f | 3080 | goto error; |
3de47213 DR |
3081 | if (disable_higher_order_debug) { |
3082 | /* | |
3083 | * Disable debugging flags that store metadata if the min slab | |
3084 | * order increased. | |
3085 | */ | |
3b0efdfa | 3086 | if (get_order(s->size) > get_order(s->object_size)) { |
3de47213 DR |
3087 | s->flags &= ~DEBUG_METADATA_FLAGS; |
3088 | s->offset = 0; | |
3089 | if (!calculate_sizes(s, -1)) | |
3090 | goto error; | |
3091 | } | |
3092 | } | |
81819f0f | 3093 | |
2565409f HC |
3094 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
3095 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
b789ef51 CL |
3096 | if (system_has_cmpxchg_double() && (s->flags & SLAB_DEBUG_FLAGS) == 0) |
3097 | /* Enable fast mode */ | |
3098 | s->flags |= __CMPXCHG_DOUBLE; | |
3099 | #endif | |
3100 | ||
3b89d7d8 DR |
3101 | /* |
3102 | * The larger the object size is, the more pages we want on the partial | |
3103 | * list to avoid pounding the page allocator excessively. | |
3104 | */ | |
49e22585 CL |
3105 | set_min_partial(s, ilog2(s->size) / 2); |
3106 | ||
3107 | /* | |
3108 | * cpu_partial determined the maximum number of objects kept in the | |
3109 | * per cpu partial lists of a processor. | |
3110 | * | |
3111 | * Per cpu partial lists mainly contain slabs that just have one | |
3112 | * object freed. If they are used for allocation then they can be | |
3113 | * filled up again with minimal effort. The slab will never hit the | |
3114 | * per node partial lists and therefore no locking will be required. | |
3115 | * | |
3116 | * This setting also determines | |
3117 | * | |
3118 | * A) The number of objects from per cpu partial slabs dumped to the | |
3119 | * per node list when we reach the limit. | |
9f264904 | 3120 | * B) The number of objects in cpu partial slabs to extract from the |
d0e0ac97 CG |
3121 | * per node list when we run out of per cpu objects. We only fetch |
3122 | * 50% to keep some capacity around for frees. | |
49e22585 | 3123 | */ |
345c905d | 3124 | if (!kmem_cache_has_cpu_partial(s)) |
8f1e33da CL |
3125 | s->cpu_partial = 0; |
3126 | else if (s->size >= PAGE_SIZE) | |
49e22585 CL |
3127 | s->cpu_partial = 2; |
3128 | else if (s->size >= 1024) | |
3129 | s->cpu_partial = 6; | |
3130 | else if (s->size >= 256) | |
3131 | s->cpu_partial = 13; | |
3132 | else | |
3133 | s->cpu_partial = 30; | |
3134 | ||
81819f0f | 3135 | #ifdef CONFIG_NUMA |
e2cb96b7 | 3136 | s->remote_node_defrag_ratio = 1000; |
81819f0f | 3137 | #endif |
55136592 | 3138 | if (!init_kmem_cache_nodes(s)) |
dfb4f096 | 3139 | goto error; |
81819f0f | 3140 | |
55136592 | 3141 | if (alloc_kmem_cache_cpus(s)) |
278b1bb1 | 3142 | return 0; |
ff12059e | 3143 | |
4c93c355 | 3144 | free_kmem_cache_nodes(s); |
81819f0f CL |
3145 | error: |
3146 | if (flags & SLAB_PANIC) | |
3147 | panic("Cannot create slab %s size=%lu realsize=%u " | |
3148 | "order=%u offset=%u flags=%lx\n", | |
d0e0ac97 CG |
3149 | s->name, (unsigned long)s->size, s->size, |
3150 | oo_order(s->oo), s->offset, flags); | |
278b1bb1 | 3151 | return -EINVAL; |
81819f0f | 3152 | } |
81819f0f | 3153 | |
33b12c38 CL |
3154 | static void list_slab_objects(struct kmem_cache *s, struct page *page, |
3155 | const char *text) | |
3156 | { | |
3157 | #ifdef CONFIG_SLUB_DEBUG | |
3158 | void *addr = page_address(page); | |
3159 | void *p; | |
a5dd5c11 NK |
3160 | unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) * |
3161 | sizeof(long), GFP_ATOMIC); | |
bbd7d57b ED |
3162 | if (!map) |
3163 | return; | |
945cf2b6 | 3164 | slab_err(s, page, text, s->name); |
33b12c38 | 3165 | slab_lock(page); |
33b12c38 | 3166 | |
5f80b13a | 3167 | get_map(s, page, map); |
33b12c38 CL |
3168 | for_each_object(p, s, addr, page->objects) { |
3169 | ||
3170 | if (!test_bit(slab_index(p, s, addr), map)) { | |
f9f58285 | 3171 | pr_err("INFO: Object 0x%p @offset=%tu\n", p, p - addr); |
33b12c38 CL |
3172 | print_tracking(s, p); |
3173 | } | |
3174 | } | |
3175 | slab_unlock(page); | |
bbd7d57b | 3176 | kfree(map); |
33b12c38 CL |
3177 | #endif |
3178 | } | |
3179 | ||
81819f0f | 3180 | /* |
599870b1 | 3181 | * Attempt to free all partial slabs on a node. |
69cb8e6b CL |
3182 | * This is called from kmem_cache_close(). We must be the last thread |
3183 | * using the cache and therefore we do not need to lock anymore. | |
81819f0f | 3184 | */ |
599870b1 | 3185 | static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) |
81819f0f | 3186 | { |
81819f0f CL |
3187 | struct page *page, *h; |
3188 | ||
33b12c38 | 3189 | list_for_each_entry_safe(page, h, &n->partial, lru) { |
81819f0f | 3190 | if (!page->inuse) { |
1e4dd946 | 3191 | __remove_partial(n, page); |
81819f0f | 3192 | discard_slab(s, page); |
33b12c38 CL |
3193 | } else { |
3194 | list_slab_objects(s, page, | |
945cf2b6 | 3195 | "Objects remaining in %s on kmem_cache_close()"); |
599870b1 | 3196 | } |
33b12c38 | 3197 | } |
81819f0f CL |
3198 | } |
3199 | ||
3200 | /* | |
672bba3a | 3201 | * Release all resources used by a slab cache. |
81819f0f | 3202 | */ |
0c710013 | 3203 | static inline int kmem_cache_close(struct kmem_cache *s) |
81819f0f CL |
3204 | { |
3205 | int node; | |
fa45dc25 | 3206 | struct kmem_cache_node *n; |
81819f0f CL |
3207 | |
3208 | flush_all(s); | |
81819f0f | 3209 | /* Attempt to free all objects */ |
fa45dc25 | 3210 | for_each_kmem_cache_node(s, node, n) { |
599870b1 CL |
3211 | free_partial(s, n); |
3212 | if (n->nr_partial || slabs_node(s, node)) | |
81819f0f CL |
3213 | return 1; |
3214 | } | |
945cf2b6 | 3215 | free_percpu(s->cpu_slab); |
81819f0f CL |
3216 | free_kmem_cache_nodes(s); |
3217 | return 0; | |
3218 | } | |
3219 | ||
945cf2b6 | 3220 | int __kmem_cache_shutdown(struct kmem_cache *s) |
81819f0f | 3221 | { |
41a21285 | 3222 | return kmem_cache_close(s); |
81819f0f | 3223 | } |
81819f0f CL |
3224 | |
3225 | /******************************************************************** | |
3226 | * Kmalloc subsystem | |
3227 | *******************************************************************/ | |
3228 | ||
81819f0f CL |
3229 | static int __init setup_slub_min_order(char *str) |
3230 | { | |
06428780 | 3231 | get_option(&str, &slub_min_order); |
81819f0f CL |
3232 | |
3233 | return 1; | |
3234 | } | |
3235 | ||
3236 | __setup("slub_min_order=", setup_slub_min_order); | |
3237 | ||
3238 | static int __init setup_slub_max_order(char *str) | |
3239 | { | |
06428780 | 3240 | get_option(&str, &slub_max_order); |
818cf590 | 3241 | slub_max_order = min(slub_max_order, MAX_ORDER - 1); |
81819f0f CL |
3242 | |
3243 | return 1; | |
3244 | } | |
3245 | ||
3246 | __setup("slub_max_order=", setup_slub_max_order); | |
3247 | ||
3248 | static int __init setup_slub_min_objects(char *str) | |
3249 | { | |
06428780 | 3250 | get_option(&str, &slub_min_objects); |
81819f0f CL |
3251 | |
3252 | return 1; | |
3253 | } | |
3254 | ||
3255 | __setup("slub_min_objects=", setup_slub_min_objects); | |
3256 | ||
81819f0f CL |
3257 | void *__kmalloc(size_t size, gfp_t flags) |
3258 | { | |
aadb4bc4 | 3259 | struct kmem_cache *s; |
5b882be4 | 3260 | void *ret; |
81819f0f | 3261 | |
95a05b42 | 3262 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) |
eada35ef | 3263 | return kmalloc_large(size, flags); |
aadb4bc4 | 3264 | |
2c59dd65 | 3265 | s = kmalloc_slab(size, flags); |
aadb4bc4 CL |
3266 | |
3267 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
3268 | return s; |
3269 | ||
2b847c3c | 3270 | ret = slab_alloc(s, flags, _RET_IP_); |
5b882be4 | 3271 | |
ca2b84cb | 3272 | trace_kmalloc(_RET_IP_, ret, size, s->size, flags); |
5b882be4 EGM |
3273 | |
3274 | return ret; | |
81819f0f CL |
3275 | } |
3276 | EXPORT_SYMBOL(__kmalloc); | |
3277 | ||
5d1f57e4 | 3278 | #ifdef CONFIG_NUMA |
f619cfe1 CL |
3279 | static void *kmalloc_large_node(size_t size, gfp_t flags, int node) |
3280 | { | |
b1eeab67 | 3281 | struct page *page; |
e4f7c0b4 | 3282 | void *ptr = NULL; |
f619cfe1 | 3283 | |
52383431 VD |
3284 | flags |= __GFP_COMP | __GFP_NOTRACK; |
3285 | page = alloc_kmem_pages_node(node, flags, get_order(size)); | |
f619cfe1 | 3286 | if (page) |
e4f7c0b4 CM |
3287 | ptr = page_address(page); |
3288 | ||
d56791b3 | 3289 | kmalloc_large_node_hook(ptr, size, flags); |
e4f7c0b4 | 3290 | return ptr; |
f619cfe1 CL |
3291 | } |
3292 | ||
81819f0f CL |
3293 | void *__kmalloc_node(size_t size, gfp_t flags, int node) |
3294 | { | |
aadb4bc4 | 3295 | struct kmem_cache *s; |
5b882be4 | 3296 | void *ret; |
81819f0f | 3297 | |
95a05b42 | 3298 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { |
5b882be4 EGM |
3299 | ret = kmalloc_large_node(size, flags, node); |
3300 | ||
ca2b84cb EGM |
3301 | trace_kmalloc_node(_RET_IP_, ret, |
3302 | size, PAGE_SIZE << get_order(size), | |
3303 | flags, node); | |
5b882be4 EGM |
3304 | |
3305 | return ret; | |
3306 | } | |
aadb4bc4 | 3307 | |
2c59dd65 | 3308 | s = kmalloc_slab(size, flags); |
aadb4bc4 CL |
3309 | |
3310 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
3311 | return s; |
3312 | ||
2b847c3c | 3313 | ret = slab_alloc_node(s, flags, node, _RET_IP_); |
5b882be4 | 3314 | |
ca2b84cb | 3315 | trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node); |
5b882be4 EGM |
3316 | |
3317 | return ret; | |
81819f0f CL |
3318 | } |
3319 | EXPORT_SYMBOL(__kmalloc_node); | |
3320 | #endif | |
3321 | ||
3322 | size_t ksize(const void *object) | |
3323 | { | |
272c1d21 | 3324 | struct page *page; |
81819f0f | 3325 | |
ef8b4520 | 3326 | if (unlikely(object == ZERO_SIZE_PTR)) |
272c1d21 CL |
3327 | return 0; |
3328 | ||
294a80a8 | 3329 | page = virt_to_head_page(object); |
294a80a8 | 3330 | |
76994412 PE |
3331 | if (unlikely(!PageSlab(page))) { |
3332 | WARN_ON(!PageCompound(page)); | |
294a80a8 | 3333 | return PAGE_SIZE << compound_order(page); |
76994412 | 3334 | } |
81819f0f | 3335 | |
1b4f59e3 | 3336 | return slab_ksize(page->slab_cache); |
81819f0f | 3337 | } |
b1aabecd | 3338 | EXPORT_SYMBOL(ksize); |
81819f0f CL |
3339 | |
3340 | void kfree(const void *x) | |
3341 | { | |
81819f0f | 3342 | struct page *page; |
5bb983b0 | 3343 | void *object = (void *)x; |
81819f0f | 3344 | |
2121db74 PE |
3345 | trace_kfree(_RET_IP_, x); |
3346 | ||
2408c550 | 3347 | if (unlikely(ZERO_OR_NULL_PTR(x))) |
81819f0f CL |
3348 | return; |
3349 | ||
b49af68f | 3350 | page = virt_to_head_page(x); |
aadb4bc4 | 3351 | if (unlikely(!PageSlab(page))) { |
0937502a | 3352 | BUG_ON(!PageCompound(page)); |
d56791b3 | 3353 | kfree_hook(x); |
52383431 | 3354 | __free_kmem_pages(page, compound_order(page)); |
aadb4bc4 CL |
3355 | return; |
3356 | } | |
1b4f59e3 | 3357 | slab_free(page->slab_cache, page, object, _RET_IP_); |
81819f0f CL |
3358 | } |
3359 | EXPORT_SYMBOL(kfree); | |
3360 | ||
2086d26a | 3361 | /* |
672bba3a CL |
3362 | * kmem_cache_shrink removes empty slabs from the partial lists and sorts |
3363 | * the remaining slabs by the number of items in use. The slabs with the | |
3364 | * most items in use come first. New allocations will then fill those up | |
3365 | * and thus they can be removed from the partial lists. | |
3366 | * | |
3367 | * The slabs with the least items are placed last. This results in them | |
3368 | * being allocated from last increasing the chance that the last objects | |
3369 | * are freed in them. | |
2086d26a | 3370 | */ |
03afc0e2 | 3371 | int __kmem_cache_shrink(struct kmem_cache *s) |
2086d26a CL |
3372 | { |
3373 | int node; | |
3374 | int i; | |
3375 | struct kmem_cache_node *n; | |
3376 | struct page *page; | |
3377 | struct page *t; | |
205ab99d | 3378 | int objects = oo_objects(s->max); |
2086d26a | 3379 | struct list_head *slabs_by_inuse = |
834f3d11 | 3380 | kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL); |
2086d26a CL |
3381 | unsigned long flags; |
3382 | ||
3383 | if (!slabs_by_inuse) | |
3384 | return -ENOMEM; | |
3385 | ||
3386 | flush_all(s); | |
fa45dc25 | 3387 | for_each_kmem_cache_node(s, node, n) { |
2086d26a CL |
3388 | if (!n->nr_partial) |
3389 | continue; | |
3390 | ||
834f3d11 | 3391 | for (i = 0; i < objects; i++) |
2086d26a CL |
3392 | INIT_LIST_HEAD(slabs_by_inuse + i); |
3393 | ||
3394 | spin_lock_irqsave(&n->list_lock, flags); | |
3395 | ||
3396 | /* | |
672bba3a | 3397 | * Build lists indexed by the items in use in each slab. |
2086d26a | 3398 | * |
672bba3a CL |
3399 | * Note that concurrent frees may occur while we hold the |
3400 | * list_lock. page->inuse here is the upper limit. | |
2086d26a CL |
3401 | */ |
3402 | list_for_each_entry_safe(page, t, &n->partial, lru) { | |
69cb8e6b CL |
3403 | list_move(&page->lru, slabs_by_inuse + page->inuse); |
3404 | if (!page->inuse) | |
3405 | n->nr_partial--; | |
2086d26a CL |
3406 | } |
3407 | ||
2086d26a | 3408 | /* |
672bba3a CL |
3409 | * Rebuild the partial list with the slabs filled up most |
3410 | * first and the least used slabs at the end. | |
2086d26a | 3411 | */ |
69cb8e6b | 3412 | for (i = objects - 1; i > 0; i--) |
2086d26a CL |
3413 | list_splice(slabs_by_inuse + i, n->partial.prev); |
3414 | ||
2086d26a | 3415 | spin_unlock_irqrestore(&n->list_lock, flags); |
69cb8e6b CL |
3416 | |
3417 | /* Release empty slabs */ | |
3418 | list_for_each_entry_safe(page, t, slabs_by_inuse, lru) | |
3419 | discard_slab(s, page); | |
2086d26a CL |
3420 | } |
3421 | ||
3422 | kfree(slabs_by_inuse); | |
3423 | return 0; | |
3424 | } | |
2086d26a | 3425 | |
b9049e23 YG |
3426 | static int slab_mem_going_offline_callback(void *arg) |
3427 | { | |
3428 | struct kmem_cache *s; | |
3429 | ||
18004c5d | 3430 | mutex_lock(&slab_mutex); |
b9049e23 | 3431 | list_for_each_entry(s, &slab_caches, list) |
03afc0e2 | 3432 | __kmem_cache_shrink(s); |
18004c5d | 3433 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
3434 | |
3435 | return 0; | |
3436 | } | |
3437 | ||
3438 | static void slab_mem_offline_callback(void *arg) | |
3439 | { | |
3440 | struct kmem_cache_node *n; | |
3441 | struct kmem_cache *s; | |
3442 | struct memory_notify *marg = arg; | |
3443 | int offline_node; | |
3444 | ||
b9d5ab25 | 3445 | offline_node = marg->status_change_nid_normal; |
b9049e23 YG |
3446 | |
3447 | /* | |
3448 | * If the node still has available memory. we need kmem_cache_node | |
3449 | * for it yet. | |
3450 | */ | |
3451 | if (offline_node < 0) | |
3452 | return; | |
3453 | ||
18004c5d | 3454 | mutex_lock(&slab_mutex); |
b9049e23 YG |
3455 | list_for_each_entry(s, &slab_caches, list) { |
3456 | n = get_node(s, offline_node); | |
3457 | if (n) { | |
3458 | /* | |
3459 | * if n->nr_slabs > 0, slabs still exist on the node | |
3460 | * that is going down. We were unable to free them, | |
c9404c9c | 3461 | * and offline_pages() function shouldn't call this |
b9049e23 YG |
3462 | * callback. So, we must fail. |
3463 | */ | |
0f389ec6 | 3464 | BUG_ON(slabs_node(s, offline_node)); |
b9049e23 YG |
3465 | |
3466 | s->node[offline_node] = NULL; | |
8de66a0c | 3467 | kmem_cache_free(kmem_cache_node, n); |
b9049e23 YG |
3468 | } |
3469 | } | |
18004c5d | 3470 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
3471 | } |
3472 | ||
3473 | static int slab_mem_going_online_callback(void *arg) | |
3474 | { | |
3475 | struct kmem_cache_node *n; | |
3476 | struct kmem_cache *s; | |
3477 | struct memory_notify *marg = arg; | |
b9d5ab25 | 3478 | int nid = marg->status_change_nid_normal; |
b9049e23 YG |
3479 | int ret = 0; |
3480 | ||
3481 | /* | |
3482 | * If the node's memory is already available, then kmem_cache_node is | |
3483 | * already created. Nothing to do. | |
3484 | */ | |
3485 | if (nid < 0) | |
3486 | return 0; | |
3487 | ||
3488 | /* | |
0121c619 | 3489 | * We are bringing a node online. No memory is available yet. We must |
b9049e23 YG |
3490 | * allocate a kmem_cache_node structure in order to bring the node |
3491 | * online. | |
3492 | */ | |
18004c5d | 3493 | mutex_lock(&slab_mutex); |
b9049e23 YG |
3494 | list_for_each_entry(s, &slab_caches, list) { |
3495 | /* | |
3496 | * XXX: kmem_cache_alloc_node will fallback to other nodes | |
3497 | * since memory is not yet available from the node that | |
3498 | * is brought up. | |
3499 | */ | |
8de66a0c | 3500 | n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); |
b9049e23 YG |
3501 | if (!n) { |
3502 | ret = -ENOMEM; | |
3503 | goto out; | |
3504 | } | |
4053497d | 3505 | init_kmem_cache_node(n); |
b9049e23 YG |
3506 | s->node[nid] = n; |
3507 | } | |
3508 | out: | |
18004c5d | 3509 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
3510 | return ret; |
3511 | } | |
3512 | ||
3513 | static int slab_memory_callback(struct notifier_block *self, | |
3514 | unsigned long action, void *arg) | |
3515 | { | |
3516 | int ret = 0; | |
3517 | ||
3518 | switch (action) { | |
3519 | case MEM_GOING_ONLINE: | |
3520 | ret = slab_mem_going_online_callback(arg); | |
3521 | break; | |
3522 | case MEM_GOING_OFFLINE: | |
3523 | ret = slab_mem_going_offline_callback(arg); | |
3524 | break; | |
3525 | case MEM_OFFLINE: | |
3526 | case MEM_CANCEL_ONLINE: | |
3527 | slab_mem_offline_callback(arg); | |
3528 | break; | |
3529 | case MEM_ONLINE: | |
3530 | case MEM_CANCEL_OFFLINE: | |
3531 | break; | |
3532 | } | |
dc19f9db KH |
3533 | if (ret) |
3534 | ret = notifier_from_errno(ret); | |
3535 | else | |
3536 | ret = NOTIFY_OK; | |
b9049e23 YG |
3537 | return ret; |
3538 | } | |
3539 | ||
3ac38faa AM |
3540 | static struct notifier_block slab_memory_callback_nb = { |
3541 | .notifier_call = slab_memory_callback, | |
3542 | .priority = SLAB_CALLBACK_PRI, | |
3543 | }; | |
b9049e23 | 3544 | |
81819f0f CL |
3545 | /******************************************************************** |
3546 | * Basic setup of slabs | |
3547 | *******************************************************************/ | |
3548 | ||
51df1142 CL |
3549 | /* |
3550 | * Used for early kmem_cache structures that were allocated using | |
dffb4d60 CL |
3551 | * the page allocator. Allocate them properly then fix up the pointers |
3552 | * that may be pointing to the wrong kmem_cache structure. | |
51df1142 CL |
3553 | */ |
3554 | ||
dffb4d60 | 3555 | static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) |
51df1142 CL |
3556 | { |
3557 | int node; | |
dffb4d60 | 3558 | struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); |
fa45dc25 | 3559 | struct kmem_cache_node *n; |
51df1142 | 3560 | |
dffb4d60 | 3561 | memcpy(s, static_cache, kmem_cache->object_size); |
51df1142 | 3562 | |
7d557b3c GC |
3563 | /* |
3564 | * This runs very early, and only the boot processor is supposed to be | |
3565 | * up. Even if it weren't true, IRQs are not up so we couldn't fire | |
3566 | * IPIs around. | |
3567 | */ | |
3568 | __flush_cpu_slab(s, smp_processor_id()); | |
fa45dc25 | 3569 | for_each_kmem_cache_node(s, node, n) { |
51df1142 CL |
3570 | struct page *p; |
3571 | ||
fa45dc25 CL |
3572 | list_for_each_entry(p, &n->partial, lru) |
3573 | p->slab_cache = s; | |
51df1142 | 3574 | |
607bf324 | 3575 | #ifdef CONFIG_SLUB_DEBUG |
fa45dc25 CL |
3576 | list_for_each_entry(p, &n->full, lru) |
3577 | p->slab_cache = s; | |
51df1142 | 3578 | #endif |
51df1142 | 3579 | } |
f7ce3190 | 3580 | slab_init_memcg_params(s); |
dffb4d60 CL |
3581 | list_add(&s->list, &slab_caches); |
3582 | return s; | |
51df1142 CL |
3583 | } |
3584 | ||
81819f0f CL |
3585 | void __init kmem_cache_init(void) |
3586 | { | |
dffb4d60 CL |
3587 | static __initdata struct kmem_cache boot_kmem_cache, |
3588 | boot_kmem_cache_node; | |
51df1142 | 3589 | |
fc8d8620 SG |
3590 | if (debug_guardpage_minorder()) |
3591 | slub_max_order = 0; | |
3592 | ||
dffb4d60 CL |
3593 | kmem_cache_node = &boot_kmem_cache_node; |
3594 | kmem_cache = &boot_kmem_cache; | |
51df1142 | 3595 | |
dffb4d60 CL |
3596 | create_boot_cache(kmem_cache_node, "kmem_cache_node", |
3597 | sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN); | |
b9049e23 | 3598 | |
3ac38faa | 3599 | register_hotmemory_notifier(&slab_memory_callback_nb); |
81819f0f CL |
3600 | |
3601 | /* Able to allocate the per node structures */ | |
3602 | slab_state = PARTIAL; | |
3603 | ||
dffb4d60 CL |
3604 | create_boot_cache(kmem_cache, "kmem_cache", |
3605 | offsetof(struct kmem_cache, node) + | |
3606 | nr_node_ids * sizeof(struct kmem_cache_node *), | |
3607 | SLAB_HWCACHE_ALIGN); | |
8a13a4cc | 3608 | |
dffb4d60 | 3609 | kmem_cache = bootstrap(&boot_kmem_cache); |
81819f0f | 3610 | |
51df1142 CL |
3611 | /* |
3612 | * Allocate kmem_cache_node properly from the kmem_cache slab. | |
3613 | * kmem_cache_node is separately allocated so no need to | |
3614 | * update any list pointers. | |
3615 | */ | |
dffb4d60 | 3616 | kmem_cache_node = bootstrap(&boot_kmem_cache_node); |
51df1142 CL |
3617 | |
3618 | /* Now we can use the kmem_cache to allocate kmalloc slabs */ | |
f97d5f63 | 3619 | create_kmalloc_caches(0); |
81819f0f CL |
3620 | |
3621 | #ifdef CONFIG_SMP | |
3622 | register_cpu_notifier(&slab_notifier); | |
9dfc6e68 | 3623 | #endif |
81819f0f | 3624 | |
f9f58285 | 3625 | pr_info("SLUB: HWalign=%d, Order=%d-%d, MinObjects=%d, CPUs=%d, Nodes=%d\n", |
f97d5f63 | 3626 | cache_line_size(), |
81819f0f CL |
3627 | slub_min_order, slub_max_order, slub_min_objects, |
3628 | nr_cpu_ids, nr_node_ids); | |
3629 | } | |
3630 | ||
7e85ee0c PE |
3631 | void __init kmem_cache_init_late(void) |
3632 | { | |
7e85ee0c PE |
3633 | } |
3634 | ||
2633d7a0 | 3635 | struct kmem_cache * |
a44cb944 VD |
3636 | __kmem_cache_alias(const char *name, size_t size, size_t align, |
3637 | unsigned long flags, void (*ctor)(void *)) | |
81819f0f CL |
3638 | { |
3639 | struct kmem_cache *s; | |
3640 | ||
a44cb944 | 3641 | s = find_mergeable(size, align, flags, name, ctor); |
81819f0f | 3642 | if (s) { |
84d0ddd6 VD |
3643 | int i; |
3644 | struct kmem_cache *c; | |
3645 | ||
81819f0f | 3646 | s->refcount++; |
84d0ddd6 | 3647 | |
81819f0f CL |
3648 | /* |
3649 | * Adjust the object sizes so that we clear | |
3650 | * the complete object on kzalloc. | |
3651 | */ | |
3b0efdfa | 3652 | s->object_size = max(s->object_size, (int)size); |
81819f0f | 3653 | s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *))); |
6446faa2 | 3654 | |
84d0ddd6 VD |
3655 | for_each_memcg_cache_index(i) { |
3656 | c = cache_from_memcg_idx(s, i); | |
3657 | if (!c) | |
3658 | continue; | |
3659 | c->object_size = s->object_size; | |
3660 | c->inuse = max_t(int, c->inuse, | |
3661 | ALIGN(size, sizeof(void *))); | |
3662 | } | |
3663 | ||
7b8f3b66 | 3664 | if (sysfs_slab_alias(s, name)) { |
7b8f3b66 | 3665 | s->refcount--; |
cbb79694 | 3666 | s = NULL; |
7b8f3b66 | 3667 | } |
a0e1d1be | 3668 | } |
6446faa2 | 3669 | |
cbb79694 CL |
3670 | return s; |
3671 | } | |
84c1cf62 | 3672 | |
8a13a4cc | 3673 | int __kmem_cache_create(struct kmem_cache *s, unsigned long flags) |
cbb79694 | 3674 | { |
aac3a166 PE |
3675 | int err; |
3676 | ||
3677 | err = kmem_cache_open(s, flags); | |
3678 | if (err) | |
3679 | return err; | |
20cea968 | 3680 | |
45530c44 CL |
3681 | /* Mutex is not taken during early boot */ |
3682 | if (slab_state <= UP) | |
3683 | return 0; | |
3684 | ||
107dab5c | 3685 | memcg_propagate_slab_attrs(s); |
aac3a166 | 3686 | err = sysfs_slab_add(s); |
aac3a166 PE |
3687 | if (err) |
3688 | kmem_cache_close(s); | |
20cea968 | 3689 | |
aac3a166 | 3690 | return err; |
81819f0f | 3691 | } |
81819f0f | 3692 | |
81819f0f | 3693 | #ifdef CONFIG_SMP |
81819f0f | 3694 | /* |
672bba3a CL |
3695 | * Use the cpu notifier to insure that the cpu slabs are flushed when |
3696 | * necessary. | |
81819f0f | 3697 | */ |
0db0628d | 3698 | static int slab_cpuup_callback(struct notifier_block *nfb, |
81819f0f CL |
3699 | unsigned long action, void *hcpu) |
3700 | { | |
3701 | long cpu = (long)hcpu; | |
5b95a4ac CL |
3702 | struct kmem_cache *s; |
3703 | unsigned long flags; | |
81819f0f CL |
3704 | |
3705 | switch (action) { | |
3706 | case CPU_UP_CANCELED: | |
8bb78442 | 3707 | case CPU_UP_CANCELED_FROZEN: |
81819f0f | 3708 | case CPU_DEAD: |
8bb78442 | 3709 | case CPU_DEAD_FROZEN: |
18004c5d | 3710 | mutex_lock(&slab_mutex); |
5b95a4ac CL |
3711 | list_for_each_entry(s, &slab_caches, list) { |
3712 | local_irq_save(flags); | |
3713 | __flush_cpu_slab(s, cpu); | |
3714 | local_irq_restore(flags); | |
3715 | } | |
18004c5d | 3716 | mutex_unlock(&slab_mutex); |
81819f0f CL |
3717 | break; |
3718 | default: | |
3719 | break; | |
3720 | } | |
3721 | return NOTIFY_OK; | |
3722 | } | |
3723 | ||
0db0628d | 3724 | static struct notifier_block slab_notifier = { |
3adbefee | 3725 | .notifier_call = slab_cpuup_callback |
06428780 | 3726 | }; |
81819f0f CL |
3727 | |
3728 | #endif | |
3729 | ||
ce71e27c | 3730 | void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller) |
81819f0f | 3731 | { |
aadb4bc4 | 3732 | struct kmem_cache *s; |
94b528d0 | 3733 | void *ret; |
aadb4bc4 | 3734 | |
95a05b42 | 3735 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) |
eada35ef PE |
3736 | return kmalloc_large(size, gfpflags); |
3737 | ||
2c59dd65 | 3738 | s = kmalloc_slab(size, gfpflags); |
81819f0f | 3739 | |
2408c550 | 3740 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 3741 | return s; |
81819f0f | 3742 | |
2b847c3c | 3743 | ret = slab_alloc(s, gfpflags, caller); |
94b528d0 | 3744 | |
25985edc | 3745 | /* Honor the call site pointer we received. */ |
ca2b84cb | 3746 | trace_kmalloc(caller, ret, size, s->size, gfpflags); |
94b528d0 EGM |
3747 | |
3748 | return ret; | |
81819f0f CL |
3749 | } |
3750 | ||
5d1f57e4 | 3751 | #ifdef CONFIG_NUMA |
81819f0f | 3752 | void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, |
ce71e27c | 3753 | int node, unsigned long caller) |
81819f0f | 3754 | { |
aadb4bc4 | 3755 | struct kmem_cache *s; |
94b528d0 | 3756 | void *ret; |
aadb4bc4 | 3757 | |
95a05b42 | 3758 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { |
d3e14aa3 XF |
3759 | ret = kmalloc_large_node(size, gfpflags, node); |
3760 | ||
3761 | trace_kmalloc_node(caller, ret, | |
3762 | size, PAGE_SIZE << get_order(size), | |
3763 | gfpflags, node); | |
3764 | ||
3765 | return ret; | |
3766 | } | |
eada35ef | 3767 | |
2c59dd65 | 3768 | s = kmalloc_slab(size, gfpflags); |
81819f0f | 3769 | |
2408c550 | 3770 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 3771 | return s; |
81819f0f | 3772 | |
2b847c3c | 3773 | ret = slab_alloc_node(s, gfpflags, node, caller); |
94b528d0 | 3774 | |
25985edc | 3775 | /* Honor the call site pointer we received. */ |
ca2b84cb | 3776 | trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node); |
94b528d0 EGM |
3777 | |
3778 | return ret; | |
81819f0f | 3779 | } |
5d1f57e4 | 3780 | #endif |
81819f0f | 3781 | |
ab4d5ed5 | 3782 | #ifdef CONFIG_SYSFS |
205ab99d CL |
3783 | static int count_inuse(struct page *page) |
3784 | { | |
3785 | return page->inuse; | |
3786 | } | |
3787 | ||
3788 | static int count_total(struct page *page) | |
3789 | { | |
3790 | return page->objects; | |
3791 | } | |
ab4d5ed5 | 3792 | #endif |
205ab99d | 3793 | |
ab4d5ed5 | 3794 | #ifdef CONFIG_SLUB_DEBUG |
434e245d CL |
3795 | static int validate_slab(struct kmem_cache *s, struct page *page, |
3796 | unsigned long *map) | |
53e15af0 CL |
3797 | { |
3798 | void *p; | |
a973e9dd | 3799 | void *addr = page_address(page); |
53e15af0 CL |
3800 | |
3801 | if (!check_slab(s, page) || | |
3802 | !on_freelist(s, page, NULL)) | |
3803 | return 0; | |
3804 | ||
3805 | /* Now we know that a valid freelist exists */ | |
39b26464 | 3806 | bitmap_zero(map, page->objects); |
53e15af0 | 3807 | |
5f80b13a CL |
3808 | get_map(s, page, map); |
3809 | for_each_object(p, s, addr, page->objects) { | |
3810 | if (test_bit(slab_index(p, s, addr), map)) | |
3811 | if (!check_object(s, page, p, SLUB_RED_INACTIVE)) | |
3812 | return 0; | |
53e15af0 CL |
3813 | } |
3814 | ||
224a88be | 3815 | for_each_object(p, s, addr, page->objects) |
7656c72b | 3816 | if (!test_bit(slab_index(p, s, addr), map)) |
37d57443 | 3817 | if (!check_object(s, page, p, SLUB_RED_ACTIVE)) |
53e15af0 CL |
3818 | return 0; |
3819 | return 1; | |
3820 | } | |
3821 | ||
434e245d CL |
3822 | static void validate_slab_slab(struct kmem_cache *s, struct page *page, |
3823 | unsigned long *map) | |
53e15af0 | 3824 | { |
881db7fb CL |
3825 | slab_lock(page); |
3826 | validate_slab(s, page, map); | |
3827 | slab_unlock(page); | |
53e15af0 CL |
3828 | } |
3829 | ||
434e245d CL |
3830 | static int validate_slab_node(struct kmem_cache *s, |
3831 | struct kmem_cache_node *n, unsigned long *map) | |
53e15af0 CL |
3832 | { |
3833 | unsigned long count = 0; | |
3834 | struct page *page; | |
3835 | unsigned long flags; | |
3836 | ||
3837 | spin_lock_irqsave(&n->list_lock, flags); | |
3838 | ||
3839 | list_for_each_entry(page, &n->partial, lru) { | |
434e245d | 3840 | validate_slab_slab(s, page, map); |
53e15af0 CL |
3841 | count++; |
3842 | } | |
3843 | if (count != n->nr_partial) | |
f9f58285 FF |
3844 | pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", |
3845 | s->name, count, n->nr_partial); | |
53e15af0 CL |
3846 | |
3847 | if (!(s->flags & SLAB_STORE_USER)) | |
3848 | goto out; | |
3849 | ||
3850 | list_for_each_entry(page, &n->full, lru) { | |
434e245d | 3851 | validate_slab_slab(s, page, map); |
53e15af0 CL |
3852 | count++; |
3853 | } | |
3854 | if (count != atomic_long_read(&n->nr_slabs)) | |
f9f58285 FF |
3855 | pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", |
3856 | s->name, count, atomic_long_read(&n->nr_slabs)); | |
53e15af0 CL |
3857 | |
3858 | out: | |
3859 | spin_unlock_irqrestore(&n->list_lock, flags); | |
3860 | return count; | |
3861 | } | |
3862 | ||
434e245d | 3863 | static long validate_slab_cache(struct kmem_cache *s) |
53e15af0 CL |
3864 | { |
3865 | int node; | |
3866 | unsigned long count = 0; | |
205ab99d | 3867 | unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) * |
434e245d | 3868 | sizeof(unsigned long), GFP_KERNEL); |
fa45dc25 | 3869 | struct kmem_cache_node *n; |
434e245d CL |
3870 | |
3871 | if (!map) | |
3872 | return -ENOMEM; | |
53e15af0 CL |
3873 | |
3874 | flush_all(s); | |
fa45dc25 | 3875 | for_each_kmem_cache_node(s, node, n) |
434e245d | 3876 | count += validate_slab_node(s, n, map); |
434e245d | 3877 | kfree(map); |
53e15af0 CL |
3878 | return count; |
3879 | } | |
88a420e4 | 3880 | /* |
672bba3a | 3881 | * Generate lists of code addresses where slabcache objects are allocated |
88a420e4 CL |
3882 | * and freed. |
3883 | */ | |
3884 | ||
3885 | struct location { | |
3886 | unsigned long count; | |
ce71e27c | 3887 | unsigned long addr; |
45edfa58 CL |
3888 | long long sum_time; |
3889 | long min_time; | |
3890 | long max_time; | |
3891 | long min_pid; | |
3892 | long max_pid; | |
174596a0 | 3893 | DECLARE_BITMAP(cpus, NR_CPUS); |
45edfa58 | 3894 | nodemask_t nodes; |
88a420e4 CL |
3895 | }; |
3896 | ||
3897 | struct loc_track { | |
3898 | unsigned long max; | |
3899 | unsigned long count; | |
3900 | struct location *loc; | |
3901 | }; | |
3902 | ||
3903 | static void free_loc_track(struct loc_track *t) | |
3904 | { | |
3905 | if (t->max) | |
3906 | free_pages((unsigned long)t->loc, | |
3907 | get_order(sizeof(struct location) * t->max)); | |
3908 | } | |
3909 | ||
68dff6a9 | 3910 | static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) |
88a420e4 CL |
3911 | { |
3912 | struct location *l; | |
3913 | int order; | |
3914 | ||
88a420e4 CL |
3915 | order = get_order(sizeof(struct location) * max); |
3916 | ||
68dff6a9 | 3917 | l = (void *)__get_free_pages(flags, order); |
88a420e4 CL |
3918 | if (!l) |
3919 | return 0; | |
3920 | ||
3921 | if (t->count) { | |
3922 | memcpy(l, t->loc, sizeof(struct location) * t->count); | |
3923 | free_loc_track(t); | |
3924 | } | |
3925 | t->max = max; | |
3926 | t->loc = l; | |
3927 | return 1; | |
3928 | } | |
3929 | ||
3930 | static int add_location(struct loc_track *t, struct kmem_cache *s, | |
45edfa58 | 3931 | const struct track *track) |
88a420e4 CL |
3932 | { |
3933 | long start, end, pos; | |
3934 | struct location *l; | |
ce71e27c | 3935 | unsigned long caddr; |
45edfa58 | 3936 | unsigned long age = jiffies - track->when; |
88a420e4 CL |
3937 | |
3938 | start = -1; | |
3939 | end = t->count; | |
3940 | ||
3941 | for ( ; ; ) { | |
3942 | pos = start + (end - start + 1) / 2; | |
3943 | ||
3944 | /* | |
3945 | * There is nothing at "end". If we end up there | |
3946 | * we need to add something to before end. | |
3947 | */ | |
3948 | if (pos == end) | |
3949 | break; | |
3950 | ||
3951 | caddr = t->loc[pos].addr; | |
45edfa58 CL |
3952 | if (track->addr == caddr) { |
3953 | ||
3954 | l = &t->loc[pos]; | |
3955 | l->count++; | |
3956 | if (track->when) { | |
3957 | l->sum_time += age; | |
3958 | if (age < l->min_time) | |
3959 | l->min_time = age; | |
3960 | if (age > l->max_time) | |
3961 | l->max_time = age; | |
3962 | ||
3963 | if (track->pid < l->min_pid) | |
3964 | l->min_pid = track->pid; | |
3965 | if (track->pid > l->max_pid) | |
3966 | l->max_pid = track->pid; | |
3967 | ||
174596a0 RR |
3968 | cpumask_set_cpu(track->cpu, |
3969 | to_cpumask(l->cpus)); | |
45edfa58 CL |
3970 | } |
3971 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
3972 | return 1; |
3973 | } | |
3974 | ||
45edfa58 | 3975 | if (track->addr < caddr) |
88a420e4 CL |
3976 | end = pos; |
3977 | else | |
3978 | start = pos; | |
3979 | } | |
3980 | ||
3981 | /* | |
672bba3a | 3982 | * Not found. Insert new tracking element. |
88a420e4 | 3983 | */ |
68dff6a9 | 3984 | if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) |
88a420e4 CL |
3985 | return 0; |
3986 | ||
3987 | l = t->loc + pos; | |
3988 | if (pos < t->count) | |
3989 | memmove(l + 1, l, | |
3990 | (t->count - pos) * sizeof(struct location)); | |
3991 | t->count++; | |
3992 | l->count = 1; | |
45edfa58 CL |
3993 | l->addr = track->addr; |
3994 | l->sum_time = age; | |
3995 | l->min_time = age; | |
3996 | l->max_time = age; | |
3997 | l->min_pid = track->pid; | |
3998 | l->max_pid = track->pid; | |
174596a0 RR |
3999 | cpumask_clear(to_cpumask(l->cpus)); |
4000 | cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); | |
45edfa58 CL |
4001 | nodes_clear(l->nodes); |
4002 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
4003 | return 1; |
4004 | } | |
4005 | ||
4006 | static void process_slab(struct loc_track *t, struct kmem_cache *s, | |
bbd7d57b | 4007 | struct page *page, enum track_item alloc, |
a5dd5c11 | 4008 | unsigned long *map) |
88a420e4 | 4009 | { |
a973e9dd | 4010 | void *addr = page_address(page); |
88a420e4 CL |
4011 | void *p; |
4012 | ||
39b26464 | 4013 | bitmap_zero(map, page->objects); |
5f80b13a | 4014 | get_map(s, page, map); |
88a420e4 | 4015 | |
224a88be | 4016 | for_each_object(p, s, addr, page->objects) |
45edfa58 CL |
4017 | if (!test_bit(slab_index(p, s, addr), map)) |
4018 | add_location(t, s, get_track(s, p, alloc)); | |
88a420e4 CL |
4019 | } |
4020 | ||
4021 | static int list_locations(struct kmem_cache *s, char *buf, | |
4022 | enum track_item alloc) | |
4023 | { | |
e374d483 | 4024 | int len = 0; |
88a420e4 | 4025 | unsigned long i; |
68dff6a9 | 4026 | struct loc_track t = { 0, 0, NULL }; |
88a420e4 | 4027 | int node; |
bbd7d57b ED |
4028 | unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) * |
4029 | sizeof(unsigned long), GFP_KERNEL); | |
fa45dc25 | 4030 | struct kmem_cache_node *n; |
88a420e4 | 4031 | |
bbd7d57b ED |
4032 | if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location), |
4033 | GFP_TEMPORARY)) { | |
4034 | kfree(map); | |
68dff6a9 | 4035 | return sprintf(buf, "Out of memory\n"); |
bbd7d57b | 4036 | } |
88a420e4 CL |
4037 | /* Push back cpu slabs */ |
4038 | flush_all(s); | |
4039 | ||
fa45dc25 | 4040 | for_each_kmem_cache_node(s, node, n) { |
88a420e4 CL |
4041 | unsigned long flags; |
4042 | struct page *page; | |
4043 | ||
9e86943b | 4044 | if (!atomic_long_read(&n->nr_slabs)) |
88a420e4 CL |
4045 | continue; |
4046 | ||
4047 | spin_lock_irqsave(&n->list_lock, flags); | |
4048 | list_for_each_entry(page, &n->partial, lru) | |
bbd7d57b | 4049 | process_slab(&t, s, page, alloc, map); |
88a420e4 | 4050 | list_for_each_entry(page, &n->full, lru) |
bbd7d57b | 4051 | process_slab(&t, s, page, alloc, map); |
88a420e4 CL |
4052 | spin_unlock_irqrestore(&n->list_lock, flags); |
4053 | } | |
4054 | ||
4055 | for (i = 0; i < t.count; i++) { | |
45edfa58 | 4056 | struct location *l = &t.loc[i]; |
88a420e4 | 4057 | |
9c246247 | 4058 | if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100) |
88a420e4 | 4059 | break; |
e374d483 | 4060 | len += sprintf(buf + len, "%7ld ", l->count); |
45edfa58 CL |
4061 | |
4062 | if (l->addr) | |
62c70bce | 4063 | len += sprintf(buf + len, "%pS", (void *)l->addr); |
88a420e4 | 4064 | else |
e374d483 | 4065 | len += sprintf(buf + len, "<not-available>"); |
45edfa58 CL |
4066 | |
4067 | if (l->sum_time != l->min_time) { | |
e374d483 | 4068 | len += sprintf(buf + len, " age=%ld/%ld/%ld", |
f8bd2258 RZ |
4069 | l->min_time, |
4070 | (long)div_u64(l->sum_time, l->count), | |
4071 | l->max_time); | |
45edfa58 | 4072 | } else |
e374d483 | 4073 | len += sprintf(buf + len, " age=%ld", |
45edfa58 CL |
4074 | l->min_time); |
4075 | ||
4076 | if (l->min_pid != l->max_pid) | |
e374d483 | 4077 | len += sprintf(buf + len, " pid=%ld-%ld", |
45edfa58 CL |
4078 | l->min_pid, l->max_pid); |
4079 | else | |
e374d483 | 4080 | len += sprintf(buf + len, " pid=%ld", |
45edfa58 CL |
4081 | l->min_pid); |
4082 | ||
174596a0 RR |
4083 | if (num_online_cpus() > 1 && |
4084 | !cpumask_empty(to_cpumask(l->cpus)) && | |
e374d483 HH |
4085 | len < PAGE_SIZE - 60) { |
4086 | len += sprintf(buf + len, " cpus="); | |
d0e0ac97 CG |
4087 | len += cpulist_scnprintf(buf + len, |
4088 | PAGE_SIZE - len - 50, | |
174596a0 | 4089 | to_cpumask(l->cpus)); |
45edfa58 CL |
4090 | } |
4091 | ||
62bc62a8 | 4092 | if (nr_online_nodes > 1 && !nodes_empty(l->nodes) && |
e374d483 HH |
4093 | len < PAGE_SIZE - 60) { |
4094 | len += sprintf(buf + len, " nodes="); | |
d0e0ac97 CG |
4095 | len += nodelist_scnprintf(buf + len, |
4096 | PAGE_SIZE - len - 50, | |
4097 | l->nodes); | |
45edfa58 CL |
4098 | } |
4099 | ||
e374d483 | 4100 | len += sprintf(buf + len, "\n"); |
88a420e4 CL |
4101 | } |
4102 | ||
4103 | free_loc_track(&t); | |
bbd7d57b | 4104 | kfree(map); |
88a420e4 | 4105 | if (!t.count) |
e374d483 HH |
4106 | len += sprintf(buf, "No data\n"); |
4107 | return len; | |
88a420e4 | 4108 | } |
ab4d5ed5 | 4109 | #endif |
88a420e4 | 4110 | |
a5a84755 | 4111 | #ifdef SLUB_RESILIENCY_TEST |
c07b8183 | 4112 | static void __init resiliency_test(void) |
a5a84755 CL |
4113 | { |
4114 | u8 *p; | |
4115 | ||
95a05b42 | 4116 | BUILD_BUG_ON(KMALLOC_MIN_SIZE > 16 || KMALLOC_SHIFT_HIGH < 10); |
a5a84755 | 4117 | |
f9f58285 FF |
4118 | pr_err("SLUB resiliency testing\n"); |
4119 | pr_err("-----------------------\n"); | |
4120 | pr_err("A. Corruption after allocation\n"); | |
a5a84755 CL |
4121 | |
4122 | p = kzalloc(16, GFP_KERNEL); | |
4123 | p[16] = 0x12; | |
f9f58285 FF |
4124 | pr_err("\n1. kmalloc-16: Clobber Redzone/next pointer 0x12->0x%p\n\n", |
4125 | p + 16); | |
a5a84755 CL |
4126 | |
4127 | validate_slab_cache(kmalloc_caches[4]); | |
4128 | ||
4129 | /* Hmmm... The next two are dangerous */ | |
4130 | p = kzalloc(32, GFP_KERNEL); | |
4131 | p[32 + sizeof(void *)] = 0x34; | |
f9f58285 FF |
4132 | pr_err("\n2. kmalloc-32: Clobber next pointer/next slab 0x34 -> -0x%p\n", |
4133 | p); | |
4134 | pr_err("If allocated object is overwritten then not detectable\n\n"); | |
a5a84755 CL |
4135 | |
4136 | validate_slab_cache(kmalloc_caches[5]); | |
4137 | p = kzalloc(64, GFP_KERNEL); | |
4138 | p += 64 + (get_cycles() & 0xff) * sizeof(void *); | |
4139 | *p = 0x56; | |
f9f58285 FF |
4140 | pr_err("\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n", |
4141 | p); | |
4142 | pr_err("If allocated object is overwritten then not detectable\n\n"); | |
a5a84755 CL |
4143 | validate_slab_cache(kmalloc_caches[6]); |
4144 | ||
f9f58285 | 4145 | pr_err("\nB. Corruption after free\n"); |
a5a84755 CL |
4146 | p = kzalloc(128, GFP_KERNEL); |
4147 | kfree(p); | |
4148 | *p = 0x78; | |
f9f58285 | 4149 | pr_err("1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p); |
a5a84755 CL |
4150 | validate_slab_cache(kmalloc_caches[7]); |
4151 | ||
4152 | p = kzalloc(256, GFP_KERNEL); | |
4153 | kfree(p); | |
4154 | p[50] = 0x9a; | |
f9f58285 | 4155 | pr_err("\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p); |
a5a84755 CL |
4156 | validate_slab_cache(kmalloc_caches[8]); |
4157 | ||
4158 | p = kzalloc(512, GFP_KERNEL); | |
4159 | kfree(p); | |
4160 | p[512] = 0xab; | |
f9f58285 | 4161 | pr_err("\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p); |
a5a84755 CL |
4162 | validate_slab_cache(kmalloc_caches[9]); |
4163 | } | |
4164 | #else | |
4165 | #ifdef CONFIG_SYSFS | |
4166 | static void resiliency_test(void) {}; | |
4167 | #endif | |
4168 | #endif | |
4169 | ||
ab4d5ed5 | 4170 | #ifdef CONFIG_SYSFS |
81819f0f | 4171 | enum slab_stat_type { |
205ab99d CL |
4172 | SL_ALL, /* All slabs */ |
4173 | SL_PARTIAL, /* Only partially allocated slabs */ | |
4174 | SL_CPU, /* Only slabs used for cpu caches */ | |
4175 | SL_OBJECTS, /* Determine allocated objects not slabs */ | |
4176 | SL_TOTAL /* Determine object capacity not slabs */ | |
81819f0f CL |
4177 | }; |
4178 | ||
205ab99d | 4179 | #define SO_ALL (1 << SL_ALL) |
81819f0f CL |
4180 | #define SO_PARTIAL (1 << SL_PARTIAL) |
4181 | #define SO_CPU (1 << SL_CPU) | |
4182 | #define SO_OBJECTS (1 << SL_OBJECTS) | |
205ab99d | 4183 | #define SO_TOTAL (1 << SL_TOTAL) |
81819f0f | 4184 | |
62e5c4b4 CG |
4185 | static ssize_t show_slab_objects(struct kmem_cache *s, |
4186 | char *buf, unsigned long flags) | |
81819f0f CL |
4187 | { |
4188 | unsigned long total = 0; | |
81819f0f CL |
4189 | int node; |
4190 | int x; | |
4191 | unsigned long *nodes; | |
81819f0f | 4192 | |
e35e1a97 | 4193 | nodes = kzalloc(sizeof(unsigned long) * nr_node_ids, GFP_KERNEL); |
62e5c4b4 CG |
4194 | if (!nodes) |
4195 | return -ENOMEM; | |
81819f0f | 4196 | |
205ab99d CL |
4197 | if (flags & SO_CPU) { |
4198 | int cpu; | |
81819f0f | 4199 | |
205ab99d | 4200 | for_each_possible_cpu(cpu) { |
d0e0ac97 CG |
4201 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, |
4202 | cpu); | |
ec3ab083 | 4203 | int node; |
49e22585 | 4204 | struct page *page; |
dfb4f096 | 4205 | |
bc6697d8 | 4206 | page = ACCESS_ONCE(c->page); |
ec3ab083 CL |
4207 | if (!page) |
4208 | continue; | |
205ab99d | 4209 | |
ec3ab083 CL |
4210 | node = page_to_nid(page); |
4211 | if (flags & SO_TOTAL) | |
4212 | x = page->objects; | |
4213 | else if (flags & SO_OBJECTS) | |
4214 | x = page->inuse; | |
4215 | else | |
4216 | x = 1; | |
49e22585 | 4217 | |
ec3ab083 CL |
4218 | total += x; |
4219 | nodes[node] += x; | |
4220 | ||
4221 | page = ACCESS_ONCE(c->partial); | |
49e22585 | 4222 | if (page) { |
8afb1474 LZ |
4223 | node = page_to_nid(page); |
4224 | if (flags & SO_TOTAL) | |
4225 | WARN_ON_ONCE(1); | |
4226 | else if (flags & SO_OBJECTS) | |
4227 | WARN_ON_ONCE(1); | |
4228 | else | |
4229 | x = page->pages; | |
bc6697d8 ED |
4230 | total += x; |
4231 | nodes[node] += x; | |
49e22585 | 4232 | } |
81819f0f CL |
4233 | } |
4234 | } | |
4235 | ||
bfc8c901 | 4236 | get_online_mems(); |
ab4d5ed5 | 4237 | #ifdef CONFIG_SLUB_DEBUG |
205ab99d | 4238 | if (flags & SO_ALL) { |
fa45dc25 CL |
4239 | struct kmem_cache_node *n; |
4240 | ||
4241 | for_each_kmem_cache_node(s, node, n) { | |
205ab99d | 4242 | |
d0e0ac97 CG |
4243 | if (flags & SO_TOTAL) |
4244 | x = atomic_long_read(&n->total_objects); | |
4245 | else if (flags & SO_OBJECTS) | |
4246 | x = atomic_long_read(&n->total_objects) - | |
4247 | count_partial(n, count_free); | |
81819f0f | 4248 | else |
205ab99d | 4249 | x = atomic_long_read(&n->nr_slabs); |
81819f0f CL |
4250 | total += x; |
4251 | nodes[node] += x; | |
4252 | } | |
4253 | ||
ab4d5ed5 CL |
4254 | } else |
4255 | #endif | |
4256 | if (flags & SO_PARTIAL) { | |
fa45dc25 | 4257 | struct kmem_cache_node *n; |
81819f0f | 4258 | |
fa45dc25 | 4259 | for_each_kmem_cache_node(s, node, n) { |
205ab99d CL |
4260 | if (flags & SO_TOTAL) |
4261 | x = count_partial(n, count_total); | |
4262 | else if (flags & SO_OBJECTS) | |
4263 | x = count_partial(n, count_inuse); | |
81819f0f | 4264 | else |
205ab99d | 4265 | x = n->nr_partial; |
81819f0f CL |
4266 | total += x; |
4267 | nodes[node] += x; | |
4268 | } | |
4269 | } | |
81819f0f CL |
4270 | x = sprintf(buf, "%lu", total); |
4271 | #ifdef CONFIG_NUMA | |
fa45dc25 | 4272 | for (node = 0; node < nr_node_ids; node++) |
81819f0f CL |
4273 | if (nodes[node]) |
4274 | x += sprintf(buf + x, " N%d=%lu", | |
4275 | node, nodes[node]); | |
4276 | #endif | |
bfc8c901 | 4277 | put_online_mems(); |
81819f0f CL |
4278 | kfree(nodes); |
4279 | return x + sprintf(buf + x, "\n"); | |
4280 | } | |
4281 | ||
ab4d5ed5 | 4282 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
4283 | static int any_slab_objects(struct kmem_cache *s) |
4284 | { | |
4285 | int node; | |
fa45dc25 | 4286 | struct kmem_cache_node *n; |
81819f0f | 4287 | |
fa45dc25 | 4288 | for_each_kmem_cache_node(s, node, n) |
4ea33e2d | 4289 | if (atomic_long_read(&n->total_objects)) |
81819f0f | 4290 | return 1; |
fa45dc25 | 4291 | |
81819f0f CL |
4292 | return 0; |
4293 | } | |
ab4d5ed5 | 4294 | #endif |
81819f0f CL |
4295 | |
4296 | #define to_slab_attr(n) container_of(n, struct slab_attribute, attr) | |
497888cf | 4297 | #define to_slab(n) container_of(n, struct kmem_cache, kobj) |
81819f0f CL |
4298 | |
4299 | struct slab_attribute { | |
4300 | struct attribute attr; | |
4301 | ssize_t (*show)(struct kmem_cache *s, char *buf); | |
4302 | ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); | |
4303 | }; | |
4304 | ||
4305 | #define SLAB_ATTR_RO(_name) \ | |
ab067e99 VK |
4306 | static struct slab_attribute _name##_attr = \ |
4307 | __ATTR(_name, 0400, _name##_show, NULL) | |
81819f0f CL |
4308 | |
4309 | #define SLAB_ATTR(_name) \ | |
4310 | static struct slab_attribute _name##_attr = \ | |
ab067e99 | 4311 | __ATTR(_name, 0600, _name##_show, _name##_store) |
81819f0f | 4312 | |
81819f0f CL |
4313 | static ssize_t slab_size_show(struct kmem_cache *s, char *buf) |
4314 | { | |
4315 | return sprintf(buf, "%d\n", s->size); | |
4316 | } | |
4317 | SLAB_ATTR_RO(slab_size); | |
4318 | ||
4319 | static ssize_t align_show(struct kmem_cache *s, char *buf) | |
4320 | { | |
4321 | return sprintf(buf, "%d\n", s->align); | |
4322 | } | |
4323 | SLAB_ATTR_RO(align); | |
4324 | ||
4325 | static ssize_t object_size_show(struct kmem_cache *s, char *buf) | |
4326 | { | |
3b0efdfa | 4327 | return sprintf(buf, "%d\n", s->object_size); |
81819f0f CL |
4328 | } |
4329 | SLAB_ATTR_RO(object_size); | |
4330 | ||
4331 | static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) | |
4332 | { | |
834f3d11 | 4333 | return sprintf(buf, "%d\n", oo_objects(s->oo)); |
81819f0f CL |
4334 | } |
4335 | SLAB_ATTR_RO(objs_per_slab); | |
4336 | ||
06b285dc CL |
4337 | static ssize_t order_store(struct kmem_cache *s, |
4338 | const char *buf, size_t length) | |
4339 | { | |
0121c619 CL |
4340 | unsigned long order; |
4341 | int err; | |
4342 | ||
3dbb95f7 | 4343 | err = kstrtoul(buf, 10, &order); |
0121c619 CL |
4344 | if (err) |
4345 | return err; | |
06b285dc CL |
4346 | |
4347 | if (order > slub_max_order || order < slub_min_order) | |
4348 | return -EINVAL; | |
4349 | ||
4350 | calculate_sizes(s, order); | |
4351 | return length; | |
4352 | } | |
4353 | ||
81819f0f CL |
4354 | static ssize_t order_show(struct kmem_cache *s, char *buf) |
4355 | { | |
834f3d11 | 4356 | return sprintf(buf, "%d\n", oo_order(s->oo)); |
81819f0f | 4357 | } |
06b285dc | 4358 | SLAB_ATTR(order); |
81819f0f | 4359 | |
73d342b1 DR |
4360 | static ssize_t min_partial_show(struct kmem_cache *s, char *buf) |
4361 | { | |
4362 | return sprintf(buf, "%lu\n", s->min_partial); | |
4363 | } | |
4364 | ||
4365 | static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, | |
4366 | size_t length) | |
4367 | { | |
4368 | unsigned long min; | |
4369 | int err; | |
4370 | ||
3dbb95f7 | 4371 | err = kstrtoul(buf, 10, &min); |
73d342b1 DR |
4372 | if (err) |
4373 | return err; | |
4374 | ||
c0bdb232 | 4375 | set_min_partial(s, min); |
73d342b1 DR |
4376 | return length; |
4377 | } | |
4378 | SLAB_ATTR(min_partial); | |
4379 | ||
49e22585 CL |
4380 | static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) |
4381 | { | |
4382 | return sprintf(buf, "%u\n", s->cpu_partial); | |
4383 | } | |
4384 | ||
4385 | static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, | |
4386 | size_t length) | |
4387 | { | |
4388 | unsigned long objects; | |
4389 | int err; | |
4390 | ||
3dbb95f7 | 4391 | err = kstrtoul(buf, 10, &objects); |
49e22585 CL |
4392 | if (err) |
4393 | return err; | |
345c905d | 4394 | if (objects && !kmem_cache_has_cpu_partial(s)) |
74ee4ef1 | 4395 | return -EINVAL; |
49e22585 CL |
4396 | |
4397 | s->cpu_partial = objects; | |
4398 | flush_all(s); | |
4399 | return length; | |
4400 | } | |
4401 | SLAB_ATTR(cpu_partial); | |
4402 | ||
81819f0f CL |
4403 | static ssize_t ctor_show(struct kmem_cache *s, char *buf) |
4404 | { | |
62c70bce JP |
4405 | if (!s->ctor) |
4406 | return 0; | |
4407 | return sprintf(buf, "%pS\n", s->ctor); | |
81819f0f CL |
4408 | } |
4409 | SLAB_ATTR_RO(ctor); | |
4410 | ||
81819f0f CL |
4411 | static ssize_t aliases_show(struct kmem_cache *s, char *buf) |
4412 | { | |
4307c14f | 4413 | return sprintf(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); |
81819f0f CL |
4414 | } |
4415 | SLAB_ATTR_RO(aliases); | |
4416 | ||
81819f0f CL |
4417 | static ssize_t partial_show(struct kmem_cache *s, char *buf) |
4418 | { | |
d9acf4b7 | 4419 | return show_slab_objects(s, buf, SO_PARTIAL); |
81819f0f CL |
4420 | } |
4421 | SLAB_ATTR_RO(partial); | |
4422 | ||
4423 | static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) | |
4424 | { | |
d9acf4b7 | 4425 | return show_slab_objects(s, buf, SO_CPU); |
81819f0f CL |
4426 | } |
4427 | SLAB_ATTR_RO(cpu_slabs); | |
4428 | ||
4429 | static ssize_t objects_show(struct kmem_cache *s, char *buf) | |
4430 | { | |
205ab99d | 4431 | return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); |
81819f0f CL |
4432 | } |
4433 | SLAB_ATTR_RO(objects); | |
4434 | ||
205ab99d CL |
4435 | static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) |
4436 | { | |
4437 | return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); | |
4438 | } | |
4439 | SLAB_ATTR_RO(objects_partial); | |
4440 | ||
49e22585 CL |
4441 | static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) |
4442 | { | |
4443 | int objects = 0; | |
4444 | int pages = 0; | |
4445 | int cpu; | |
4446 | int len; | |
4447 | ||
4448 | for_each_online_cpu(cpu) { | |
4449 | struct page *page = per_cpu_ptr(s->cpu_slab, cpu)->partial; | |
4450 | ||
4451 | if (page) { | |
4452 | pages += page->pages; | |
4453 | objects += page->pobjects; | |
4454 | } | |
4455 | } | |
4456 | ||
4457 | len = sprintf(buf, "%d(%d)", objects, pages); | |
4458 | ||
4459 | #ifdef CONFIG_SMP | |
4460 | for_each_online_cpu(cpu) { | |
4461 | struct page *page = per_cpu_ptr(s->cpu_slab, cpu) ->partial; | |
4462 | ||
4463 | if (page && len < PAGE_SIZE - 20) | |
4464 | len += sprintf(buf + len, " C%d=%d(%d)", cpu, | |
4465 | page->pobjects, page->pages); | |
4466 | } | |
4467 | #endif | |
4468 | return len + sprintf(buf + len, "\n"); | |
4469 | } | |
4470 | SLAB_ATTR_RO(slabs_cpu_partial); | |
4471 | ||
a5a84755 CL |
4472 | static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) |
4473 | { | |
4474 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); | |
4475 | } | |
4476 | ||
4477 | static ssize_t reclaim_account_store(struct kmem_cache *s, | |
4478 | const char *buf, size_t length) | |
4479 | { | |
4480 | s->flags &= ~SLAB_RECLAIM_ACCOUNT; | |
4481 | if (buf[0] == '1') | |
4482 | s->flags |= SLAB_RECLAIM_ACCOUNT; | |
4483 | return length; | |
4484 | } | |
4485 | SLAB_ATTR(reclaim_account); | |
4486 | ||
4487 | static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) | |
4488 | { | |
4489 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); | |
4490 | } | |
4491 | SLAB_ATTR_RO(hwcache_align); | |
4492 | ||
4493 | #ifdef CONFIG_ZONE_DMA | |
4494 | static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) | |
4495 | { | |
4496 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); | |
4497 | } | |
4498 | SLAB_ATTR_RO(cache_dma); | |
4499 | #endif | |
4500 | ||
4501 | static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) | |
4502 | { | |
4503 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU)); | |
4504 | } | |
4505 | SLAB_ATTR_RO(destroy_by_rcu); | |
4506 | ||
ab9a0f19 LJ |
4507 | static ssize_t reserved_show(struct kmem_cache *s, char *buf) |
4508 | { | |
4509 | return sprintf(buf, "%d\n", s->reserved); | |
4510 | } | |
4511 | SLAB_ATTR_RO(reserved); | |
4512 | ||
ab4d5ed5 | 4513 | #ifdef CONFIG_SLUB_DEBUG |
a5a84755 CL |
4514 | static ssize_t slabs_show(struct kmem_cache *s, char *buf) |
4515 | { | |
4516 | return show_slab_objects(s, buf, SO_ALL); | |
4517 | } | |
4518 | SLAB_ATTR_RO(slabs); | |
4519 | ||
205ab99d CL |
4520 | static ssize_t total_objects_show(struct kmem_cache *s, char *buf) |
4521 | { | |
4522 | return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); | |
4523 | } | |
4524 | SLAB_ATTR_RO(total_objects); | |
4525 | ||
81819f0f CL |
4526 | static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) |
4527 | { | |
4528 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE)); | |
4529 | } | |
4530 | ||
4531 | static ssize_t sanity_checks_store(struct kmem_cache *s, | |
4532 | const char *buf, size_t length) | |
4533 | { | |
4534 | s->flags &= ~SLAB_DEBUG_FREE; | |
b789ef51 CL |
4535 | if (buf[0] == '1') { |
4536 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4537 | s->flags |= SLAB_DEBUG_FREE; |
b789ef51 | 4538 | } |
81819f0f CL |
4539 | return length; |
4540 | } | |
4541 | SLAB_ATTR(sanity_checks); | |
4542 | ||
4543 | static ssize_t trace_show(struct kmem_cache *s, char *buf) | |
4544 | { | |
4545 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE)); | |
4546 | } | |
4547 | ||
4548 | static ssize_t trace_store(struct kmem_cache *s, const char *buf, | |
4549 | size_t length) | |
4550 | { | |
c9e16131 CL |
4551 | /* |
4552 | * Tracing a merged cache is going to give confusing results | |
4553 | * as well as cause other issues like converting a mergeable | |
4554 | * cache into an umergeable one. | |
4555 | */ | |
4556 | if (s->refcount > 1) | |
4557 | return -EINVAL; | |
4558 | ||
81819f0f | 4559 | s->flags &= ~SLAB_TRACE; |
b789ef51 CL |
4560 | if (buf[0] == '1') { |
4561 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4562 | s->flags |= SLAB_TRACE; |
b789ef51 | 4563 | } |
81819f0f CL |
4564 | return length; |
4565 | } | |
4566 | SLAB_ATTR(trace); | |
4567 | ||
81819f0f CL |
4568 | static ssize_t red_zone_show(struct kmem_cache *s, char *buf) |
4569 | { | |
4570 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); | |
4571 | } | |
4572 | ||
4573 | static ssize_t red_zone_store(struct kmem_cache *s, | |
4574 | const char *buf, size_t length) | |
4575 | { | |
4576 | if (any_slab_objects(s)) | |
4577 | return -EBUSY; | |
4578 | ||
4579 | s->flags &= ~SLAB_RED_ZONE; | |
b789ef51 CL |
4580 | if (buf[0] == '1') { |
4581 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4582 | s->flags |= SLAB_RED_ZONE; |
b789ef51 | 4583 | } |
06b285dc | 4584 | calculate_sizes(s, -1); |
81819f0f CL |
4585 | return length; |
4586 | } | |
4587 | SLAB_ATTR(red_zone); | |
4588 | ||
4589 | static ssize_t poison_show(struct kmem_cache *s, char *buf) | |
4590 | { | |
4591 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON)); | |
4592 | } | |
4593 | ||
4594 | static ssize_t poison_store(struct kmem_cache *s, | |
4595 | const char *buf, size_t length) | |
4596 | { | |
4597 | if (any_slab_objects(s)) | |
4598 | return -EBUSY; | |
4599 | ||
4600 | s->flags &= ~SLAB_POISON; | |
b789ef51 CL |
4601 | if (buf[0] == '1') { |
4602 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4603 | s->flags |= SLAB_POISON; |
b789ef51 | 4604 | } |
06b285dc | 4605 | calculate_sizes(s, -1); |
81819f0f CL |
4606 | return length; |
4607 | } | |
4608 | SLAB_ATTR(poison); | |
4609 | ||
4610 | static ssize_t store_user_show(struct kmem_cache *s, char *buf) | |
4611 | { | |
4612 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); | |
4613 | } | |
4614 | ||
4615 | static ssize_t store_user_store(struct kmem_cache *s, | |
4616 | const char *buf, size_t length) | |
4617 | { | |
4618 | if (any_slab_objects(s)) | |
4619 | return -EBUSY; | |
4620 | ||
4621 | s->flags &= ~SLAB_STORE_USER; | |
b789ef51 CL |
4622 | if (buf[0] == '1') { |
4623 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 4624 | s->flags |= SLAB_STORE_USER; |
b789ef51 | 4625 | } |
06b285dc | 4626 | calculate_sizes(s, -1); |
81819f0f CL |
4627 | return length; |
4628 | } | |
4629 | SLAB_ATTR(store_user); | |
4630 | ||
53e15af0 CL |
4631 | static ssize_t validate_show(struct kmem_cache *s, char *buf) |
4632 | { | |
4633 | return 0; | |
4634 | } | |
4635 | ||
4636 | static ssize_t validate_store(struct kmem_cache *s, | |
4637 | const char *buf, size_t length) | |
4638 | { | |
434e245d CL |
4639 | int ret = -EINVAL; |
4640 | ||
4641 | if (buf[0] == '1') { | |
4642 | ret = validate_slab_cache(s); | |
4643 | if (ret >= 0) | |
4644 | ret = length; | |
4645 | } | |
4646 | return ret; | |
53e15af0 CL |
4647 | } |
4648 | SLAB_ATTR(validate); | |
a5a84755 CL |
4649 | |
4650 | static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf) | |
4651 | { | |
4652 | if (!(s->flags & SLAB_STORE_USER)) | |
4653 | return -ENOSYS; | |
4654 | return list_locations(s, buf, TRACK_ALLOC); | |
4655 | } | |
4656 | SLAB_ATTR_RO(alloc_calls); | |
4657 | ||
4658 | static ssize_t free_calls_show(struct kmem_cache *s, char *buf) | |
4659 | { | |
4660 | if (!(s->flags & SLAB_STORE_USER)) | |
4661 | return -ENOSYS; | |
4662 | return list_locations(s, buf, TRACK_FREE); | |
4663 | } | |
4664 | SLAB_ATTR_RO(free_calls); | |
4665 | #endif /* CONFIG_SLUB_DEBUG */ | |
4666 | ||
4667 | #ifdef CONFIG_FAILSLAB | |
4668 | static ssize_t failslab_show(struct kmem_cache *s, char *buf) | |
4669 | { | |
4670 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); | |
4671 | } | |
4672 | ||
4673 | static ssize_t failslab_store(struct kmem_cache *s, const char *buf, | |
4674 | size_t length) | |
4675 | { | |
c9e16131 CL |
4676 | if (s->refcount > 1) |
4677 | return -EINVAL; | |
4678 | ||
a5a84755 CL |
4679 | s->flags &= ~SLAB_FAILSLAB; |
4680 | if (buf[0] == '1') | |
4681 | s->flags |= SLAB_FAILSLAB; | |
4682 | return length; | |
4683 | } | |
4684 | SLAB_ATTR(failslab); | |
ab4d5ed5 | 4685 | #endif |
53e15af0 | 4686 | |
2086d26a CL |
4687 | static ssize_t shrink_show(struct kmem_cache *s, char *buf) |
4688 | { | |
4689 | return 0; | |
4690 | } | |
4691 | ||
4692 | static ssize_t shrink_store(struct kmem_cache *s, | |
4693 | const char *buf, size_t length) | |
4694 | { | |
4695 | if (buf[0] == '1') { | |
4696 | int rc = kmem_cache_shrink(s); | |
4697 | ||
4698 | if (rc) | |
4699 | return rc; | |
4700 | } else | |
4701 | return -EINVAL; | |
4702 | return length; | |
4703 | } | |
4704 | SLAB_ATTR(shrink); | |
4705 | ||
81819f0f | 4706 | #ifdef CONFIG_NUMA |
9824601e | 4707 | static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) |
81819f0f | 4708 | { |
9824601e | 4709 | return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10); |
81819f0f CL |
4710 | } |
4711 | ||
9824601e | 4712 | static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, |
81819f0f CL |
4713 | const char *buf, size_t length) |
4714 | { | |
0121c619 CL |
4715 | unsigned long ratio; |
4716 | int err; | |
4717 | ||
3dbb95f7 | 4718 | err = kstrtoul(buf, 10, &ratio); |
0121c619 CL |
4719 | if (err) |
4720 | return err; | |
4721 | ||
e2cb96b7 | 4722 | if (ratio <= 100) |
0121c619 | 4723 | s->remote_node_defrag_ratio = ratio * 10; |
81819f0f | 4724 | |
81819f0f CL |
4725 | return length; |
4726 | } | |
9824601e | 4727 | SLAB_ATTR(remote_node_defrag_ratio); |
81819f0f CL |
4728 | #endif |
4729 | ||
8ff12cfc | 4730 | #ifdef CONFIG_SLUB_STATS |
8ff12cfc CL |
4731 | static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) |
4732 | { | |
4733 | unsigned long sum = 0; | |
4734 | int cpu; | |
4735 | int len; | |
4736 | int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); | |
4737 | ||
4738 | if (!data) | |
4739 | return -ENOMEM; | |
4740 | ||
4741 | for_each_online_cpu(cpu) { | |
9dfc6e68 | 4742 | unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; |
8ff12cfc CL |
4743 | |
4744 | data[cpu] = x; | |
4745 | sum += x; | |
4746 | } | |
4747 | ||
4748 | len = sprintf(buf, "%lu", sum); | |
4749 | ||
50ef37b9 | 4750 | #ifdef CONFIG_SMP |
8ff12cfc CL |
4751 | for_each_online_cpu(cpu) { |
4752 | if (data[cpu] && len < PAGE_SIZE - 20) | |
50ef37b9 | 4753 | len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]); |
8ff12cfc | 4754 | } |
50ef37b9 | 4755 | #endif |
8ff12cfc CL |
4756 | kfree(data); |
4757 | return len + sprintf(buf + len, "\n"); | |
4758 | } | |
4759 | ||
78eb00cc DR |
4760 | static void clear_stat(struct kmem_cache *s, enum stat_item si) |
4761 | { | |
4762 | int cpu; | |
4763 | ||
4764 | for_each_online_cpu(cpu) | |
9dfc6e68 | 4765 | per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; |
78eb00cc DR |
4766 | } |
4767 | ||
8ff12cfc CL |
4768 | #define STAT_ATTR(si, text) \ |
4769 | static ssize_t text##_show(struct kmem_cache *s, char *buf) \ | |
4770 | { \ | |
4771 | return show_stat(s, buf, si); \ | |
4772 | } \ | |
78eb00cc DR |
4773 | static ssize_t text##_store(struct kmem_cache *s, \ |
4774 | const char *buf, size_t length) \ | |
4775 | { \ | |
4776 | if (buf[0] != '0') \ | |
4777 | return -EINVAL; \ | |
4778 | clear_stat(s, si); \ | |
4779 | return length; \ | |
4780 | } \ | |
4781 | SLAB_ATTR(text); \ | |
8ff12cfc CL |
4782 | |
4783 | STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); | |
4784 | STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); | |
4785 | STAT_ATTR(FREE_FASTPATH, free_fastpath); | |
4786 | STAT_ATTR(FREE_SLOWPATH, free_slowpath); | |
4787 | STAT_ATTR(FREE_FROZEN, free_frozen); | |
4788 | STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); | |
4789 | STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); | |
4790 | STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); | |
4791 | STAT_ATTR(ALLOC_SLAB, alloc_slab); | |
4792 | STAT_ATTR(ALLOC_REFILL, alloc_refill); | |
e36a2652 | 4793 | STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); |
8ff12cfc CL |
4794 | STAT_ATTR(FREE_SLAB, free_slab); |
4795 | STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); | |
4796 | STAT_ATTR(DEACTIVATE_FULL, deactivate_full); | |
4797 | STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); | |
4798 | STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); | |
4799 | STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); | |
4800 | STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); | |
03e404af | 4801 | STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); |
65c3376a | 4802 | STAT_ATTR(ORDER_FALLBACK, order_fallback); |
b789ef51 CL |
4803 | STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); |
4804 | STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); | |
49e22585 CL |
4805 | STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); |
4806 | STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); | |
8028dcea AS |
4807 | STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); |
4808 | STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); | |
8ff12cfc CL |
4809 | #endif |
4810 | ||
06428780 | 4811 | static struct attribute *slab_attrs[] = { |
81819f0f CL |
4812 | &slab_size_attr.attr, |
4813 | &object_size_attr.attr, | |
4814 | &objs_per_slab_attr.attr, | |
4815 | &order_attr.attr, | |
73d342b1 | 4816 | &min_partial_attr.attr, |
49e22585 | 4817 | &cpu_partial_attr.attr, |
81819f0f | 4818 | &objects_attr.attr, |
205ab99d | 4819 | &objects_partial_attr.attr, |
81819f0f CL |
4820 | &partial_attr.attr, |
4821 | &cpu_slabs_attr.attr, | |
4822 | &ctor_attr.attr, | |
81819f0f CL |
4823 | &aliases_attr.attr, |
4824 | &align_attr.attr, | |
81819f0f CL |
4825 | &hwcache_align_attr.attr, |
4826 | &reclaim_account_attr.attr, | |
4827 | &destroy_by_rcu_attr.attr, | |
a5a84755 | 4828 | &shrink_attr.attr, |
ab9a0f19 | 4829 | &reserved_attr.attr, |
49e22585 | 4830 | &slabs_cpu_partial_attr.attr, |
ab4d5ed5 | 4831 | #ifdef CONFIG_SLUB_DEBUG |
a5a84755 CL |
4832 | &total_objects_attr.attr, |
4833 | &slabs_attr.attr, | |
4834 | &sanity_checks_attr.attr, | |
4835 | &trace_attr.attr, | |
81819f0f CL |
4836 | &red_zone_attr.attr, |
4837 | &poison_attr.attr, | |
4838 | &store_user_attr.attr, | |
53e15af0 | 4839 | &validate_attr.attr, |
88a420e4 CL |
4840 | &alloc_calls_attr.attr, |
4841 | &free_calls_attr.attr, | |
ab4d5ed5 | 4842 | #endif |
81819f0f CL |
4843 | #ifdef CONFIG_ZONE_DMA |
4844 | &cache_dma_attr.attr, | |
4845 | #endif | |
4846 | #ifdef CONFIG_NUMA | |
9824601e | 4847 | &remote_node_defrag_ratio_attr.attr, |
8ff12cfc CL |
4848 | #endif |
4849 | #ifdef CONFIG_SLUB_STATS | |
4850 | &alloc_fastpath_attr.attr, | |
4851 | &alloc_slowpath_attr.attr, | |
4852 | &free_fastpath_attr.attr, | |
4853 | &free_slowpath_attr.attr, | |
4854 | &free_frozen_attr.attr, | |
4855 | &free_add_partial_attr.attr, | |
4856 | &free_remove_partial_attr.attr, | |
4857 | &alloc_from_partial_attr.attr, | |
4858 | &alloc_slab_attr.attr, | |
4859 | &alloc_refill_attr.attr, | |
e36a2652 | 4860 | &alloc_node_mismatch_attr.attr, |
8ff12cfc CL |
4861 | &free_slab_attr.attr, |
4862 | &cpuslab_flush_attr.attr, | |
4863 | &deactivate_full_attr.attr, | |
4864 | &deactivate_empty_attr.attr, | |
4865 | &deactivate_to_head_attr.attr, | |
4866 | &deactivate_to_tail_attr.attr, | |
4867 | &deactivate_remote_frees_attr.attr, | |
03e404af | 4868 | &deactivate_bypass_attr.attr, |
65c3376a | 4869 | &order_fallback_attr.attr, |
b789ef51 CL |
4870 | &cmpxchg_double_fail_attr.attr, |
4871 | &cmpxchg_double_cpu_fail_attr.attr, | |
49e22585 CL |
4872 | &cpu_partial_alloc_attr.attr, |
4873 | &cpu_partial_free_attr.attr, | |
8028dcea AS |
4874 | &cpu_partial_node_attr.attr, |
4875 | &cpu_partial_drain_attr.attr, | |
81819f0f | 4876 | #endif |
4c13dd3b DM |
4877 | #ifdef CONFIG_FAILSLAB |
4878 | &failslab_attr.attr, | |
4879 | #endif | |
4880 | ||
81819f0f CL |
4881 | NULL |
4882 | }; | |
4883 | ||
4884 | static struct attribute_group slab_attr_group = { | |
4885 | .attrs = slab_attrs, | |
4886 | }; | |
4887 | ||
4888 | static ssize_t slab_attr_show(struct kobject *kobj, | |
4889 | struct attribute *attr, | |
4890 | char *buf) | |
4891 | { | |
4892 | struct slab_attribute *attribute; | |
4893 | struct kmem_cache *s; | |
4894 | int err; | |
4895 | ||
4896 | attribute = to_slab_attr(attr); | |
4897 | s = to_slab(kobj); | |
4898 | ||
4899 | if (!attribute->show) | |
4900 | return -EIO; | |
4901 | ||
4902 | err = attribute->show(s, buf); | |
4903 | ||
4904 | return err; | |
4905 | } | |
4906 | ||
4907 | static ssize_t slab_attr_store(struct kobject *kobj, | |
4908 | struct attribute *attr, | |
4909 | const char *buf, size_t len) | |
4910 | { | |
4911 | struct slab_attribute *attribute; | |
4912 | struct kmem_cache *s; | |
4913 | int err; | |
4914 | ||
4915 | attribute = to_slab_attr(attr); | |
4916 | s = to_slab(kobj); | |
4917 | ||
4918 | if (!attribute->store) | |
4919 | return -EIO; | |
4920 | ||
4921 | err = attribute->store(s, buf, len); | |
107dab5c GC |
4922 | #ifdef CONFIG_MEMCG_KMEM |
4923 | if (slab_state >= FULL && err >= 0 && is_root_cache(s)) { | |
4924 | int i; | |
81819f0f | 4925 | |
107dab5c GC |
4926 | mutex_lock(&slab_mutex); |
4927 | if (s->max_attr_size < len) | |
4928 | s->max_attr_size = len; | |
4929 | ||
ebe945c2 GC |
4930 | /* |
4931 | * This is a best effort propagation, so this function's return | |
4932 | * value will be determined by the parent cache only. This is | |
4933 | * basically because not all attributes will have a well | |
4934 | * defined semantics for rollbacks - most of the actions will | |
4935 | * have permanent effects. | |
4936 | * | |
4937 | * Returning the error value of any of the children that fail | |
4938 | * is not 100 % defined, in the sense that users seeing the | |
4939 | * error code won't be able to know anything about the state of | |
4940 | * the cache. | |
4941 | * | |
4942 | * Only returning the error code for the parent cache at least | |
4943 | * has well defined semantics. The cache being written to | |
4944 | * directly either failed or succeeded, in which case we loop | |
4945 | * through the descendants with best-effort propagation. | |
4946 | */ | |
107dab5c | 4947 | for_each_memcg_cache_index(i) { |
2ade4de8 | 4948 | struct kmem_cache *c = cache_from_memcg_idx(s, i); |
107dab5c GC |
4949 | if (c) |
4950 | attribute->store(c, buf, len); | |
4951 | } | |
4952 | mutex_unlock(&slab_mutex); | |
4953 | } | |
4954 | #endif | |
81819f0f CL |
4955 | return err; |
4956 | } | |
4957 | ||
107dab5c GC |
4958 | static void memcg_propagate_slab_attrs(struct kmem_cache *s) |
4959 | { | |
4960 | #ifdef CONFIG_MEMCG_KMEM | |
4961 | int i; | |
4962 | char *buffer = NULL; | |
93030d83 | 4963 | struct kmem_cache *root_cache; |
107dab5c | 4964 | |
93030d83 | 4965 | if (is_root_cache(s)) |
107dab5c GC |
4966 | return; |
4967 | ||
f7ce3190 | 4968 | root_cache = s->memcg_params.root_cache; |
93030d83 | 4969 | |
107dab5c GC |
4970 | /* |
4971 | * This mean this cache had no attribute written. Therefore, no point | |
4972 | * in copying default values around | |
4973 | */ | |
93030d83 | 4974 | if (!root_cache->max_attr_size) |
107dab5c GC |
4975 | return; |
4976 | ||
4977 | for (i = 0; i < ARRAY_SIZE(slab_attrs); i++) { | |
4978 | char mbuf[64]; | |
4979 | char *buf; | |
4980 | struct slab_attribute *attr = to_slab_attr(slab_attrs[i]); | |
4981 | ||
4982 | if (!attr || !attr->store || !attr->show) | |
4983 | continue; | |
4984 | ||
4985 | /* | |
4986 | * It is really bad that we have to allocate here, so we will | |
4987 | * do it only as a fallback. If we actually allocate, though, | |
4988 | * we can just use the allocated buffer until the end. | |
4989 | * | |
4990 | * Most of the slub attributes will tend to be very small in | |
4991 | * size, but sysfs allows buffers up to a page, so they can | |
4992 | * theoretically happen. | |
4993 | */ | |
4994 | if (buffer) | |
4995 | buf = buffer; | |
93030d83 | 4996 | else if (root_cache->max_attr_size < ARRAY_SIZE(mbuf)) |
107dab5c GC |
4997 | buf = mbuf; |
4998 | else { | |
4999 | buffer = (char *) get_zeroed_page(GFP_KERNEL); | |
5000 | if (WARN_ON(!buffer)) | |
5001 | continue; | |
5002 | buf = buffer; | |
5003 | } | |
5004 | ||
93030d83 | 5005 | attr->show(root_cache, buf); |
107dab5c GC |
5006 | attr->store(s, buf, strlen(buf)); |
5007 | } | |
5008 | ||
5009 | if (buffer) | |
5010 | free_page((unsigned long)buffer); | |
5011 | #endif | |
5012 | } | |
5013 | ||
41a21285 CL |
5014 | static void kmem_cache_release(struct kobject *k) |
5015 | { | |
5016 | slab_kmem_cache_release(to_slab(k)); | |
5017 | } | |
5018 | ||
52cf25d0 | 5019 | static const struct sysfs_ops slab_sysfs_ops = { |
81819f0f CL |
5020 | .show = slab_attr_show, |
5021 | .store = slab_attr_store, | |
5022 | }; | |
5023 | ||
5024 | static struct kobj_type slab_ktype = { | |
5025 | .sysfs_ops = &slab_sysfs_ops, | |
41a21285 | 5026 | .release = kmem_cache_release, |
81819f0f CL |
5027 | }; |
5028 | ||
5029 | static int uevent_filter(struct kset *kset, struct kobject *kobj) | |
5030 | { | |
5031 | struct kobj_type *ktype = get_ktype(kobj); | |
5032 | ||
5033 | if (ktype == &slab_ktype) | |
5034 | return 1; | |
5035 | return 0; | |
5036 | } | |
5037 | ||
9cd43611 | 5038 | static const struct kset_uevent_ops slab_uevent_ops = { |
81819f0f CL |
5039 | .filter = uevent_filter, |
5040 | }; | |
5041 | ||
27c3a314 | 5042 | static struct kset *slab_kset; |
81819f0f | 5043 | |
9a41707b VD |
5044 | static inline struct kset *cache_kset(struct kmem_cache *s) |
5045 | { | |
5046 | #ifdef CONFIG_MEMCG_KMEM | |
5047 | if (!is_root_cache(s)) | |
f7ce3190 | 5048 | return s->memcg_params.root_cache->memcg_kset; |
9a41707b VD |
5049 | #endif |
5050 | return slab_kset; | |
5051 | } | |
5052 | ||
81819f0f CL |
5053 | #define ID_STR_LENGTH 64 |
5054 | ||
5055 | /* Create a unique string id for a slab cache: | |
6446faa2 CL |
5056 | * |
5057 | * Format :[flags-]size | |
81819f0f CL |
5058 | */ |
5059 | static char *create_unique_id(struct kmem_cache *s) | |
5060 | { | |
5061 | char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); | |
5062 | char *p = name; | |
5063 | ||
5064 | BUG_ON(!name); | |
5065 | ||
5066 | *p++ = ':'; | |
5067 | /* | |
5068 | * First flags affecting slabcache operations. We will only | |
5069 | * get here for aliasable slabs so we do not need to support | |
5070 | * too many flags. The flags here must cover all flags that | |
5071 | * are matched during merging to guarantee that the id is | |
5072 | * unique. | |
5073 | */ | |
5074 | if (s->flags & SLAB_CACHE_DMA) | |
5075 | *p++ = 'd'; | |
5076 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
5077 | *p++ = 'a'; | |
5078 | if (s->flags & SLAB_DEBUG_FREE) | |
5079 | *p++ = 'F'; | |
5a896d9e VN |
5080 | if (!(s->flags & SLAB_NOTRACK)) |
5081 | *p++ = 't'; | |
81819f0f CL |
5082 | if (p != name + 1) |
5083 | *p++ = '-'; | |
5084 | p += sprintf(p, "%07d", s->size); | |
2633d7a0 | 5085 | |
81819f0f CL |
5086 | BUG_ON(p > name + ID_STR_LENGTH - 1); |
5087 | return name; | |
5088 | } | |
5089 | ||
5090 | static int sysfs_slab_add(struct kmem_cache *s) | |
5091 | { | |
5092 | int err; | |
5093 | const char *name; | |
45530c44 | 5094 | int unmergeable = slab_unmergeable(s); |
81819f0f | 5095 | |
81819f0f CL |
5096 | if (unmergeable) { |
5097 | /* | |
5098 | * Slabcache can never be merged so we can use the name proper. | |
5099 | * This is typically the case for debug situations. In that | |
5100 | * case we can catch duplicate names easily. | |
5101 | */ | |
27c3a314 | 5102 | sysfs_remove_link(&slab_kset->kobj, s->name); |
81819f0f CL |
5103 | name = s->name; |
5104 | } else { | |
5105 | /* | |
5106 | * Create a unique name for the slab as a target | |
5107 | * for the symlinks. | |
5108 | */ | |
5109 | name = create_unique_id(s); | |
5110 | } | |
5111 | ||
9a41707b | 5112 | s->kobj.kset = cache_kset(s); |
26e4f205 | 5113 | err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); |
54b6a731 DJ |
5114 | if (err) |
5115 | goto out_put_kobj; | |
81819f0f CL |
5116 | |
5117 | err = sysfs_create_group(&s->kobj, &slab_attr_group); | |
54b6a731 DJ |
5118 | if (err) |
5119 | goto out_del_kobj; | |
9a41707b VD |
5120 | |
5121 | #ifdef CONFIG_MEMCG_KMEM | |
5122 | if (is_root_cache(s)) { | |
5123 | s->memcg_kset = kset_create_and_add("cgroup", NULL, &s->kobj); | |
5124 | if (!s->memcg_kset) { | |
54b6a731 DJ |
5125 | err = -ENOMEM; |
5126 | goto out_del_kobj; | |
9a41707b VD |
5127 | } |
5128 | } | |
5129 | #endif | |
5130 | ||
81819f0f CL |
5131 | kobject_uevent(&s->kobj, KOBJ_ADD); |
5132 | if (!unmergeable) { | |
5133 | /* Setup first alias */ | |
5134 | sysfs_slab_alias(s, s->name); | |
81819f0f | 5135 | } |
54b6a731 DJ |
5136 | out: |
5137 | if (!unmergeable) | |
5138 | kfree(name); | |
5139 | return err; | |
5140 | out_del_kobj: | |
5141 | kobject_del(&s->kobj); | |
5142 | out_put_kobj: | |
5143 | kobject_put(&s->kobj); | |
5144 | goto out; | |
81819f0f CL |
5145 | } |
5146 | ||
41a21285 | 5147 | void sysfs_slab_remove(struct kmem_cache *s) |
81819f0f | 5148 | { |
97d06609 | 5149 | if (slab_state < FULL) |
2bce6485 CL |
5150 | /* |
5151 | * Sysfs has not been setup yet so no need to remove the | |
5152 | * cache from sysfs. | |
5153 | */ | |
5154 | return; | |
5155 | ||
9a41707b VD |
5156 | #ifdef CONFIG_MEMCG_KMEM |
5157 | kset_unregister(s->memcg_kset); | |
5158 | #endif | |
81819f0f CL |
5159 | kobject_uevent(&s->kobj, KOBJ_REMOVE); |
5160 | kobject_del(&s->kobj); | |
151c602f | 5161 | kobject_put(&s->kobj); |
81819f0f CL |
5162 | } |
5163 | ||
5164 | /* | |
5165 | * Need to buffer aliases during bootup until sysfs becomes | |
9f6c708e | 5166 | * available lest we lose that information. |
81819f0f CL |
5167 | */ |
5168 | struct saved_alias { | |
5169 | struct kmem_cache *s; | |
5170 | const char *name; | |
5171 | struct saved_alias *next; | |
5172 | }; | |
5173 | ||
5af328a5 | 5174 | static struct saved_alias *alias_list; |
81819f0f CL |
5175 | |
5176 | static int sysfs_slab_alias(struct kmem_cache *s, const char *name) | |
5177 | { | |
5178 | struct saved_alias *al; | |
5179 | ||
97d06609 | 5180 | if (slab_state == FULL) { |
81819f0f CL |
5181 | /* |
5182 | * If we have a leftover link then remove it. | |
5183 | */ | |
27c3a314 GKH |
5184 | sysfs_remove_link(&slab_kset->kobj, name); |
5185 | return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); | |
81819f0f CL |
5186 | } |
5187 | ||
5188 | al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); | |
5189 | if (!al) | |
5190 | return -ENOMEM; | |
5191 | ||
5192 | al->s = s; | |
5193 | al->name = name; | |
5194 | al->next = alias_list; | |
5195 | alias_list = al; | |
5196 | return 0; | |
5197 | } | |
5198 | ||
5199 | static int __init slab_sysfs_init(void) | |
5200 | { | |
5b95a4ac | 5201 | struct kmem_cache *s; |
81819f0f CL |
5202 | int err; |
5203 | ||
18004c5d | 5204 | mutex_lock(&slab_mutex); |
2bce6485 | 5205 | |
0ff21e46 | 5206 | slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj); |
27c3a314 | 5207 | if (!slab_kset) { |
18004c5d | 5208 | mutex_unlock(&slab_mutex); |
f9f58285 | 5209 | pr_err("Cannot register slab subsystem.\n"); |
81819f0f CL |
5210 | return -ENOSYS; |
5211 | } | |
5212 | ||
97d06609 | 5213 | slab_state = FULL; |
26a7bd03 | 5214 | |
5b95a4ac | 5215 | list_for_each_entry(s, &slab_caches, list) { |
26a7bd03 | 5216 | err = sysfs_slab_add(s); |
5d540fb7 | 5217 | if (err) |
f9f58285 FF |
5218 | pr_err("SLUB: Unable to add boot slab %s to sysfs\n", |
5219 | s->name); | |
26a7bd03 | 5220 | } |
81819f0f CL |
5221 | |
5222 | while (alias_list) { | |
5223 | struct saved_alias *al = alias_list; | |
5224 | ||
5225 | alias_list = alias_list->next; | |
5226 | err = sysfs_slab_alias(al->s, al->name); | |
5d540fb7 | 5227 | if (err) |
f9f58285 FF |
5228 | pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", |
5229 | al->name); | |
81819f0f CL |
5230 | kfree(al); |
5231 | } | |
5232 | ||
18004c5d | 5233 | mutex_unlock(&slab_mutex); |
81819f0f CL |
5234 | resiliency_test(); |
5235 | return 0; | |
5236 | } | |
5237 | ||
5238 | __initcall(slab_sysfs_init); | |
ab4d5ed5 | 5239 | #endif /* CONFIG_SYSFS */ |
57ed3eda PE |
5240 | |
5241 | /* | |
5242 | * The /proc/slabinfo ABI | |
5243 | */ | |
158a9624 | 5244 | #ifdef CONFIG_SLABINFO |
0d7561c6 | 5245 | void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) |
57ed3eda | 5246 | { |
57ed3eda | 5247 | unsigned long nr_slabs = 0; |
205ab99d CL |
5248 | unsigned long nr_objs = 0; |
5249 | unsigned long nr_free = 0; | |
57ed3eda | 5250 | int node; |
fa45dc25 | 5251 | struct kmem_cache_node *n; |
57ed3eda | 5252 | |
fa45dc25 | 5253 | for_each_kmem_cache_node(s, node, n) { |
c17fd13e WL |
5254 | nr_slabs += node_nr_slabs(n); |
5255 | nr_objs += node_nr_objs(n); | |
205ab99d | 5256 | nr_free += count_partial(n, count_free); |
57ed3eda PE |
5257 | } |
5258 | ||
0d7561c6 GC |
5259 | sinfo->active_objs = nr_objs - nr_free; |
5260 | sinfo->num_objs = nr_objs; | |
5261 | sinfo->active_slabs = nr_slabs; | |
5262 | sinfo->num_slabs = nr_slabs; | |
5263 | sinfo->objects_per_slab = oo_objects(s->oo); | |
5264 | sinfo->cache_order = oo_order(s->oo); | |
57ed3eda PE |
5265 | } |
5266 | ||
0d7561c6 | 5267 | void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) |
7b3c3a50 | 5268 | { |
7b3c3a50 AD |
5269 | } |
5270 | ||
b7454ad3 GC |
5271 | ssize_t slabinfo_write(struct file *file, const char __user *buffer, |
5272 | size_t count, loff_t *ppos) | |
7b3c3a50 | 5273 | { |
b7454ad3 | 5274 | return -EIO; |
7b3c3a50 | 5275 | } |
158a9624 | 5276 | #endif /* CONFIG_SLABINFO */ |