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Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
81819f0f CL |
2 | /* |
3 | * SLUB: A slab allocator that limits cache line use instead of queuing | |
4 | * objects in per cpu and per node lists. | |
5 | * | |
881db7fb CL |
6 | * The allocator synchronizes using per slab locks or atomic operatios |
7 | * and only uses a centralized lock to manage a pool of partial slabs. | |
81819f0f | 8 | * |
cde53535 | 9 | * (C) 2007 SGI, Christoph Lameter |
881db7fb | 10 | * (C) 2011 Linux Foundation, Christoph Lameter |
81819f0f CL |
11 | */ |
12 | ||
13 | #include <linux/mm.h> | |
1eb5ac64 | 14 | #include <linux/swap.h> /* struct reclaim_state */ |
81819f0f CL |
15 | #include <linux/module.h> |
16 | #include <linux/bit_spinlock.h> | |
17 | #include <linux/interrupt.h> | |
18 | #include <linux/bitops.h> | |
19 | #include <linux/slab.h> | |
97d06609 | 20 | #include "slab.h" |
7b3c3a50 | 21 | #include <linux/proc_fs.h> |
81819f0f | 22 | #include <linux/seq_file.h> |
a79316c6 | 23 | #include <linux/kasan.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> |
2482ddec | 36 | #include <linux/random.h> |
81819f0f | 37 | |
4a92379b RK |
38 | #include <trace/events/kmem.h> |
39 | ||
072bb0aa MG |
40 | #include "internal.h" |
41 | ||
81819f0f CL |
42 | /* |
43 | * Lock order: | |
18004c5d | 44 | * 1. slab_mutex (Global Mutex) |
881db7fb CL |
45 | * 2. node->list_lock |
46 | * 3. slab_lock(page) (Only on some arches and for debugging) | |
81819f0f | 47 | * |
18004c5d | 48 | * slab_mutex |
881db7fb | 49 | * |
18004c5d | 50 | * The role of the slab_mutex is to protect the list of all the slabs |
881db7fb CL |
51 | * and to synchronize major metadata changes to slab cache structures. |
52 | * | |
53 | * The slab_lock is only used for debugging and on arches that do not | |
b7ccc7f8 | 54 | * have the ability to do a cmpxchg_double. It only protects: |
881db7fb | 55 | * A. page->freelist -> List of object free in a page |
b7ccc7f8 MW |
56 | * B. page->inuse -> Number of objects in use |
57 | * C. page->objects -> Number of objects in page | |
58 | * D. page->frozen -> frozen state | |
881db7fb CL |
59 | * |
60 | * If a slab is frozen then it is exempt from list management. It is not | |
61 | * on any list. The processor that froze the slab is the one who can | |
62 | * perform list operations on the page. Other processors may put objects | |
63 | * onto the freelist but the processor that froze the slab is the only | |
64 | * one that can retrieve the objects from the page's freelist. | |
81819f0f CL |
65 | * |
66 | * The list_lock protects the partial and full list on each node and | |
67 | * the partial slab counter. If taken then no new slabs may be added or | |
68 | * removed from the lists nor make the number of partial slabs be modified. | |
69 | * (Note that the total number of slabs is an atomic value that may be | |
70 | * modified without taking the list lock). | |
71 | * | |
72 | * The list_lock is a centralized lock and thus we avoid taking it as | |
73 | * much as possible. As long as SLUB does not have to handle partial | |
74 | * slabs, operations can continue without any centralized lock. F.e. | |
75 | * allocating a long series of objects that fill up slabs does not require | |
76 | * the list lock. | |
81819f0f CL |
77 | * Interrupts are disabled during allocation and deallocation in order to |
78 | * make the slab allocator safe to use in the context of an irq. In addition | |
79 | * interrupts are disabled to ensure that the processor does not change | |
80 | * while handling per_cpu slabs, due to kernel preemption. | |
81 | * | |
82 | * SLUB assigns one slab for allocation to each processor. | |
83 | * Allocations only occur from these slabs called cpu slabs. | |
84 | * | |
672bba3a CL |
85 | * Slabs with free elements are kept on a partial list and during regular |
86 | * operations no list for full slabs is used. If an object in a full slab is | |
81819f0f | 87 | * freed then the slab will show up again on the partial lists. |
672bba3a CL |
88 | * We track full slabs for debugging purposes though because otherwise we |
89 | * cannot scan all objects. | |
81819f0f CL |
90 | * |
91 | * Slabs are freed when they become empty. Teardown and setup is | |
92 | * minimal so we rely on the page allocators per cpu caches for | |
93 | * fast frees and allocs. | |
94 | * | |
95 | * Overloading of page flags that are otherwise used for LRU management. | |
96 | * | |
4b6f0750 CL |
97 | * PageActive The slab is frozen and exempt from list processing. |
98 | * This means that the slab is dedicated to a purpose | |
99 | * such as satisfying allocations for a specific | |
100 | * processor. Objects may be freed in the slab while | |
101 | * it is frozen but slab_free will then skip the usual | |
102 | * list operations. It is up to the processor holding | |
103 | * the slab to integrate the slab into the slab lists | |
104 | * when the slab is no longer needed. | |
105 | * | |
106 | * One use of this flag is to mark slabs that are | |
107 | * used for allocations. Then such a slab becomes a cpu | |
108 | * slab. The cpu slab may be equipped with an additional | |
dfb4f096 | 109 | * freelist that allows lockless access to |
894b8788 CL |
110 | * free objects in addition to the regular freelist |
111 | * that requires the slab lock. | |
81819f0f CL |
112 | * |
113 | * PageError Slab requires special handling due to debug | |
114 | * options set. This moves slab handling out of | |
894b8788 | 115 | * the fast path and disables lockless freelists. |
81819f0f CL |
116 | */ |
117 | ||
af537b0a CL |
118 | static inline int kmem_cache_debug(struct kmem_cache *s) |
119 | { | |
5577bd8a | 120 | #ifdef CONFIG_SLUB_DEBUG |
af537b0a | 121 | return unlikely(s->flags & SLAB_DEBUG_FLAGS); |
5577bd8a | 122 | #else |
af537b0a | 123 | return 0; |
5577bd8a | 124 | #endif |
af537b0a | 125 | } |
5577bd8a | 126 | |
117d54df | 127 | void *fixup_red_left(struct kmem_cache *s, void *p) |
d86bd1be JK |
128 | { |
129 | if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) | |
130 | p += s->red_left_pad; | |
131 | ||
132 | return p; | |
133 | } | |
134 | ||
345c905d JK |
135 | static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) |
136 | { | |
137 | #ifdef CONFIG_SLUB_CPU_PARTIAL | |
138 | return !kmem_cache_debug(s); | |
139 | #else | |
140 | return false; | |
141 | #endif | |
142 | } | |
143 | ||
81819f0f CL |
144 | /* |
145 | * Issues still to be resolved: | |
146 | * | |
81819f0f CL |
147 | * - Support PAGE_ALLOC_DEBUG. Should be easy to do. |
148 | * | |
81819f0f CL |
149 | * - Variable sizing of the per node arrays |
150 | */ | |
151 | ||
152 | /* Enable to test recovery from slab corruption on boot */ | |
153 | #undef SLUB_RESILIENCY_TEST | |
154 | ||
b789ef51 CL |
155 | /* Enable to log cmpxchg failures */ |
156 | #undef SLUB_DEBUG_CMPXCHG | |
157 | ||
2086d26a CL |
158 | /* |
159 | * Mininum number of partial slabs. These will be left on the partial | |
160 | * lists even if they are empty. kmem_cache_shrink may reclaim them. | |
161 | */ | |
76be8950 | 162 | #define MIN_PARTIAL 5 |
e95eed57 | 163 | |
2086d26a CL |
164 | /* |
165 | * Maximum number of desirable partial slabs. | |
166 | * The existence of more partial slabs makes kmem_cache_shrink | |
721ae22a | 167 | * sort the partial list by the number of objects in use. |
2086d26a CL |
168 | */ |
169 | #define MAX_PARTIAL 10 | |
170 | ||
becfda68 | 171 | #define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \ |
81819f0f | 172 | SLAB_POISON | SLAB_STORE_USER) |
672bba3a | 173 | |
149daaf3 LA |
174 | /* |
175 | * These debug flags cannot use CMPXCHG because there might be consistency | |
176 | * issues when checking or reading debug information | |
177 | */ | |
178 | #define SLAB_NO_CMPXCHG (SLAB_CONSISTENCY_CHECKS | SLAB_STORE_USER | \ | |
179 | SLAB_TRACE) | |
180 | ||
181 | ||
fa5ec8a1 | 182 | /* |
3de47213 DR |
183 | * Debugging flags that require metadata to be stored in the slab. These get |
184 | * disabled when slub_debug=O is used and a cache's min order increases with | |
185 | * metadata. | |
fa5ec8a1 | 186 | */ |
3de47213 | 187 | #define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) |
fa5ec8a1 | 188 | |
210b5c06 CG |
189 | #define OO_SHIFT 16 |
190 | #define OO_MASK ((1 << OO_SHIFT) - 1) | |
50d5c41c | 191 | #define MAX_OBJS_PER_PAGE 32767 /* since page.objects is u15 */ |
210b5c06 | 192 | |
81819f0f | 193 | /* Internal SLUB flags */ |
d50112ed | 194 | /* Poison object */ |
4fd0b46e | 195 | #define __OBJECT_POISON ((slab_flags_t __force)0x80000000U) |
d50112ed | 196 | /* Use cmpxchg_double */ |
4fd0b46e | 197 | #define __CMPXCHG_DOUBLE ((slab_flags_t __force)0x40000000U) |
81819f0f | 198 | |
02cbc874 CL |
199 | /* |
200 | * Tracking user of a slab. | |
201 | */ | |
d6543e39 | 202 | #define TRACK_ADDRS_COUNT 16 |
02cbc874 | 203 | struct track { |
ce71e27c | 204 | unsigned long addr; /* Called from address */ |
d6543e39 BG |
205 | #ifdef CONFIG_STACKTRACE |
206 | unsigned long addrs[TRACK_ADDRS_COUNT]; /* Called from address */ | |
207 | #endif | |
02cbc874 CL |
208 | int cpu; /* Was running on cpu */ |
209 | int pid; /* Pid context */ | |
210 | unsigned long when; /* When did the operation occur */ | |
211 | }; | |
212 | ||
213 | enum track_item { TRACK_ALLOC, TRACK_FREE }; | |
214 | ||
ab4d5ed5 | 215 | #ifdef CONFIG_SYSFS |
81819f0f CL |
216 | static int sysfs_slab_add(struct kmem_cache *); |
217 | static int sysfs_slab_alias(struct kmem_cache *, const char *); | |
107dab5c | 218 | static void memcg_propagate_slab_attrs(struct kmem_cache *s); |
bf5eb3de | 219 | static void sysfs_slab_remove(struct kmem_cache *s); |
81819f0f | 220 | #else |
0c710013 CL |
221 | static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } |
222 | static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) | |
223 | { return 0; } | |
107dab5c | 224 | static inline void memcg_propagate_slab_attrs(struct kmem_cache *s) { } |
bf5eb3de | 225 | static inline void sysfs_slab_remove(struct kmem_cache *s) { } |
81819f0f CL |
226 | #endif |
227 | ||
4fdccdfb | 228 | static inline void stat(const struct kmem_cache *s, enum stat_item si) |
8ff12cfc CL |
229 | { |
230 | #ifdef CONFIG_SLUB_STATS | |
88da03a6 CL |
231 | /* |
232 | * The rmw is racy on a preemptible kernel but this is acceptable, so | |
233 | * avoid this_cpu_add()'s irq-disable overhead. | |
234 | */ | |
235 | raw_cpu_inc(s->cpu_slab->stat[si]); | |
8ff12cfc CL |
236 | #endif |
237 | } | |
238 | ||
81819f0f CL |
239 | /******************************************************************** |
240 | * Core slab cache functions | |
241 | *******************************************************************/ | |
242 | ||
2482ddec KC |
243 | /* |
244 | * Returns freelist pointer (ptr). With hardening, this is obfuscated | |
245 | * with an XOR of the address where the pointer is held and a per-cache | |
246 | * random number. | |
247 | */ | |
248 | static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr, | |
249 | unsigned long ptr_addr) | |
250 | { | |
251 | #ifdef CONFIG_SLAB_FREELIST_HARDENED | |
252 | return (void *)((unsigned long)ptr ^ s->random ^ ptr_addr); | |
253 | #else | |
254 | return ptr; | |
255 | #endif | |
256 | } | |
257 | ||
258 | /* Returns the freelist pointer recorded at location ptr_addr. */ | |
259 | static inline void *freelist_dereference(const struct kmem_cache *s, | |
260 | void *ptr_addr) | |
261 | { | |
262 | return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr), | |
263 | (unsigned long)ptr_addr); | |
264 | } | |
265 | ||
7656c72b CL |
266 | static inline void *get_freepointer(struct kmem_cache *s, void *object) |
267 | { | |
2482ddec | 268 | return freelist_dereference(s, object + s->offset); |
7656c72b CL |
269 | } |
270 | ||
0ad9500e ED |
271 | static void prefetch_freepointer(const struct kmem_cache *s, void *object) |
272 | { | |
0882ff91 | 273 | prefetch(object + s->offset); |
0ad9500e ED |
274 | } |
275 | ||
1393d9a1 CL |
276 | static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) |
277 | { | |
2482ddec | 278 | unsigned long freepointer_addr; |
1393d9a1 CL |
279 | void *p; |
280 | ||
922d566c JK |
281 | if (!debug_pagealloc_enabled()) |
282 | return get_freepointer(s, object); | |
283 | ||
2482ddec KC |
284 | freepointer_addr = (unsigned long)object + s->offset; |
285 | probe_kernel_read(&p, (void **)freepointer_addr, sizeof(p)); | |
286 | return freelist_ptr(s, p, freepointer_addr); | |
1393d9a1 CL |
287 | } |
288 | ||
7656c72b CL |
289 | static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) |
290 | { | |
2482ddec KC |
291 | unsigned long freeptr_addr = (unsigned long)object + s->offset; |
292 | ||
ce6fa91b AP |
293 | #ifdef CONFIG_SLAB_FREELIST_HARDENED |
294 | BUG_ON(object == fp); /* naive detection of double free or corruption */ | |
295 | #endif | |
296 | ||
2482ddec | 297 | *(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr); |
7656c72b CL |
298 | } |
299 | ||
300 | /* Loop over all objects in a slab */ | |
224a88be | 301 | #define for_each_object(__p, __s, __addr, __objects) \ |
d86bd1be JK |
302 | for (__p = fixup_red_left(__s, __addr); \ |
303 | __p < (__addr) + (__objects) * (__s)->size; \ | |
304 | __p += (__s)->size) | |
7656c72b | 305 | |
54266640 | 306 | #define for_each_object_idx(__p, __idx, __s, __addr, __objects) \ |
d86bd1be JK |
307 | for (__p = fixup_red_left(__s, __addr), __idx = 1; \ |
308 | __idx <= __objects; \ | |
309 | __p += (__s)->size, __idx++) | |
54266640 | 310 | |
7656c72b | 311 | /* Determine object index from a given position */ |
284b50dd | 312 | static inline unsigned int slab_index(void *p, struct kmem_cache *s, void *addr) |
7656c72b CL |
313 | { |
314 | return (p - addr) / s->size; | |
315 | } | |
316 | ||
9736d2a9 | 317 | static inline unsigned int order_objects(unsigned int order, unsigned int size) |
ab9a0f19 | 318 | { |
9736d2a9 | 319 | return ((unsigned int)PAGE_SIZE << order) / size; |
ab9a0f19 LJ |
320 | } |
321 | ||
19af27af | 322 | static inline struct kmem_cache_order_objects oo_make(unsigned int order, |
9736d2a9 | 323 | unsigned int size) |
834f3d11 CL |
324 | { |
325 | struct kmem_cache_order_objects x = { | |
9736d2a9 | 326 | (order << OO_SHIFT) + order_objects(order, size) |
834f3d11 CL |
327 | }; |
328 | ||
329 | return x; | |
330 | } | |
331 | ||
19af27af | 332 | static inline unsigned int oo_order(struct kmem_cache_order_objects x) |
834f3d11 | 333 | { |
210b5c06 | 334 | return x.x >> OO_SHIFT; |
834f3d11 CL |
335 | } |
336 | ||
19af27af | 337 | static inline unsigned int oo_objects(struct kmem_cache_order_objects x) |
834f3d11 | 338 | { |
210b5c06 | 339 | return x.x & OO_MASK; |
834f3d11 CL |
340 | } |
341 | ||
881db7fb CL |
342 | /* |
343 | * Per slab locking using the pagelock | |
344 | */ | |
345 | static __always_inline void slab_lock(struct page *page) | |
346 | { | |
48c935ad | 347 | VM_BUG_ON_PAGE(PageTail(page), page); |
881db7fb CL |
348 | bit_spin_lock(PG_locked, &page->flags); |
349 | } | |
350 | ||
351 | static __always_inline void slab_unlock(struct page *page) | |
352 | { | |
48c935ad | 353 | VM_BUG_ON_PAGE(PageTail(page), page); |
881db7fb CL |
354 | __bit_spin_unlock(PG_locked, &page->flags); |
355 | } | |
356 | ||
1d07171c CL |
357 | /* Interrupts must be disabled (for the fallback code to work right) */ |
358 | static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page, | |
359 | void *freelist_old, unsigned long counters_old, | |
360 | void *freelist_new, unsigned long counters_new, | |
361 | const char *n) | |
362 | { | |
363 | VM_BUG_ON(!irqs_disabled()); | |
2565409f HC |
364 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
365 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
1d07171c | 366 | if (s->flags & __CMPXCHG_DOUBLE) { |
cdcd6298 | 367 | if (cmpxchg_double(&page->freelist, &page->counters, |
0aa9a13d DC |
368 | freelist_old, counters_old, |
369 | freelist_new, counters_new)) | |
6f6528a1 | 370 | return true; |
1d07171c CL |
371 | } else |
372 | #endif | |
373 | { | |
374 | slab_lock(page); | |
d0e0ac97 CG |
375 | if (page->freelist == freelist_old && |
376 | page->counters == counters_old) { | |
1d07171c | 377 | page->freelist = freelist_new; |
7d27a04b | 378 | page->counters = counters_new; |
1d07171c | 379 | slab_unlock(page); |
6f6528a1 | 380 | return true; |
1d07171c CL |
381 | } |
382 | slab_unlock(page); | |
383 | } | |
384 | ||
385 | cpu_relax(); | |
386 | stat(s, CMPXCHG_DOUBLE_FAIL); | |
387 | ||
388 | #ifdef SLUB_DEBUG_CMPXCHG | |
f9f58285 | 389 | pr_info("%s %s: cmpxchg double redo ", n, s->name); |
1d07171c CL |
390 | #endif |
391 | ||
6f6528a1 | 392 | return false; |
1d07171c CL |
393 | } |
394 | ||
b789ef51 CL |
395 | static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page, |
396 | void *freelist_old, unsigned long counters_old, | |
397 | void *freelist_new, unsigned long counters_new, | |
398 | const char *n) | |
399 | { | |
2565409f HC |
400 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
401 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
b789ef51 | 402 | if (s->flags & __CMPXCHG_DOUBLE) { |
cdcd6298 | 403 | if (cmpxchg_double(&page->freelist, &page->counters, |
0aa9a13d DC |
404 | freelist_old, counters_old, |
405 | freelist_new, counters_new)) | |
6f6528a1 | 406 | return true; |
b789ef51 CL |
407 | } else |
408 | #endif | |
409 | { | |
1d07171c CL |
410 | unsigned long flags; |
411 | ||
412 | local_irq_save(flags); | |
881db7fb | 413 | slab_lock(page); |
d0e0ac97 CG |
414 | if (page->freelist == freelist_old && |
415 | page->counters == counters_old) { | |
b789ef51 | 416 | page->freelist = freelist_new; |
7d27a04b | 417 | page->counters = counters_new; |
881db7fb | 418 | slab_unlock(page); |
1d07171c | 419 | local_irq_restore(flags); |
6f6528a1 | 420 | return true; |
b789ef51 | 421 | } |
881db7fb | 422 | slab_unlock(page); |
1d07171c | 423 | local_irq_restore(flags); |
b789ef51 CL |
424 | } |
425 | ||
426 | cpu_relax(); | |
427 | stat(s, CMPXCHG_DOUBLE_FAIL); | |
428 | ||
429 | #ifdef SLUB_DEBUG_CMPXCHG | |
f9f58285 | 430 | pr_info("%s %s: cmpxchg double redo ", n, s->name); |
b789ef51 CL |
431 | #endif |
432 | ||
6f6528a1 | 433 | return false; |
b789ef51 CL |
434 | } |
435 | ||
41ecc55b | 436 | #ifdef CONFIG_SLUB_DEBUG |
5f80b13a CL |
437 | /* |
438 | * Determine a map of object in use on a page. | |
439 | * | |
881db7fb | 440 | * Node listlock must be held to guarantee that the page does |
5f80b13a CL |
441 | * not vanish from under us. |
442 | */ | |
443 | static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map) | |
444 | { | |
445 | void *p; | |
446 | void *addr = page_address(page); | |
447 | ||
448 | for (p = page->freelist; p; p = get_freepointer(s, p)) | |
449 | set_bit(slab_index(p, s, addr), map); | |
450 | } | |
451 | ||
870b1fbb | 452 | static inline unsigned int size_from_object(struct kmem_cache *s) |
d86bd1be JK |
453 | { |
454 | if (s->flags & SLAB_RED_ZONE) | |
455 | return s->size - s->red_left_pad; | |
456 | ||
457 | return s->size; | |
458 | } | |
459 | ||
460 | static inline void *restore_red_left(struct kmem_cache *s, void *p) | |
461 | { | |
462 | if (s->flags & SLAB_RED_ZONE) | |
463 | p -= s->red_left_pad; | |
464 | ||
465 | return p; | |
466 | } | |
467 | ||
41ecc55b CL |
468 | /* |
469 | * Debug settings: | |
470 | */ | |
89d3c87e | 471 | #if defined(CONFIG_SLUB_DEBUG_ON) |
d50112ed | 472 | static slab_flags_t slub_debug = DEBUG_DEFAULT_FLAGS; |
f0630fff | 473 | #else |
d50112ed | 474 | static slab_flags_t slub_debug; |
f0630fff | 475 | #endif |
41ecc55b CL |
476 | |
477 | static char *slub_debug_slabs; | |
fa5ec8a1 | 478 | static int disable_higher_order_debug; |
41ecc55b | 479 | |
a79316c6 AR |
480 | /* |
481 | * slub is about to manipulate internal object metadata. This memory lies | |
482 | * outside the range of the allocated object, so accessing it would normally | |
483 | * be reported by kasan as a bounds error. metadata_access_enable() is used | |
484 | * to tell kasan that these accesses are OK. | |
485 | */ | |
486 | static inline void metadata_access_enable(void) | |
487 | { | |
488 | kasan_disable_current(); | |
489 | } | |
490 | ||
491 | static inline void metadata_access_disable(void) | |
492 | { | |
493 | kasan_enable_current(); | |
494 | } | |
495 | ||
81819f0f CL |
496 | /* |
497 | * Object debugging | |
498 | */ | |
d86bd1be JK |
499 | |
500 | /* Verify that a pointer has an address that is valid within a slab page */ | |
501 | static inline int check_valid_pointer(struct kmem_cache *s, | |
502 | struct page *page, void *object) | |
503 | { | |
504 | void *base; | |
505 | ||
506 | if (!object) | |
507 | return 1; | |
508 | ||
509 | base = page_address(page); | |
510 | object = restore_red_left(s, object); | |
511 | if (object < base || object >= base + page->objects * s->size || | |
512 | (object - base) % s->size) { | |
513 | return 0; | |
514 | } | |
515 | ||
516 | return 1; | |
517 | } | |
518 | ||
aa2efd5e DT |
519 | static void print_section(char *level, char *text, u8 *addr, |
520 | unsigned int length) | |
81819f0f | 521 | { |
a79316c6 | 522 | metadata_access_enable(); |
aa2efd5e | 523 | print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, |
ffc79d28 | 524 | length, 1); |
a79316c6 | 525 | metadata_access_disable(); |
81819f0f CL |
526 | } |
527 | ||
81819f0f CL |
528 | static struct track *get_track(struct kmem_cache *s, void *object, |
529 | enum track_item alloc) | |
530 | { | |
531 | struct track *p; | |
532 | ||
533 | if (s->offset) | |
534 | p = object + s->offset + sizeof(void *); | |
535 | else | |
536 | p = object + s->inuse; | |
537 | ||
538 | return p + alloc; | |
539 | } | |
540 | ||
541 | static void set_track(struct kmem_cache *s, void *object, | |
ce71e27c | 542 | enum track_item alloc, unsigned long addr) |
81819f0f | 543 | { |
1a00df4a | 544 | struct track *p = get_track(s, object, alloc); |
81819f0f | 545 | |
81819f0f | 546 | if (addr) { |
d6543e39 BG |
547 | #ifdef CONFIG_STACKTRACE |
548 | struct stack_trace trace; | |
549 | int i; | |
550 | ||
551 | trace.nr_entries = 0; | |
552 | trace.max_entries = TRACK_ADDRS_COUNT; | |
553 | trace.entries = p->addrs; | |
554 | trace.skip = 3; | |
a79316c6 | 555 | metadata_access_enable(); |
d6543e39 | 556 | save_stack_trace(&trace); |
a79316c6 | 557 | metadata_access_disable(); |
d6543e39 BG |
558 | |
559 | /* See rant in lockdep.c */ | |
560 | if (trace.nr_entries != 0 && | |
561 | trace.entries[trace.nr_entries - 1] == ULONG_MAX) | |
562 | trace.nr_entries--; | |
563 | ||
564 | for (i = trace.nr_entries; i < TRACK_ADDRS_COUNT; i++) | |
565 | p->addrs[i] = 0; | |
566 | #endif | |
81819f0f CL |
567 | p->addr = addr; |
568 | p->cpu = smp_processor_id(); | |
88e4ccf2 | 569 | p->pid = current->pid; |
81819f0f CL |
570 | p->when = jiffies; |
571 | } else | |
572 | memset(p, 0, sizeof(struct track)); | |
573 | } | |
574 | ||
81819f0f CL |
575 | static void init_tracking(struct kmem_cache *s, void *object) |
576 | { | |
24922684 CL |
577 | if (!(s->flags & SLAB_STORE_USER)) |
578 | return; | |
579 | ||
ce71e27c EGM |
580 | set_track(s, object, TRACK_FREE, 0UL); |
581 | set_track(s, object, TRACK_ALLOC, 0UL); | |
81819f0f CL |
582 | } |
583 | ||
86609d33 | 584 | static void print_track(const char *s, struct track *t, unsigned long pr_time) |
81819f0f CL |
585 | { |
586 | if (!t->addr) | |
587 | return; | |
588 | ||
f9f58285 | 589 | pr_err("INFO: %s in %pS age=%lu cpu=%u pid=%d\n", |
86609d33 | 590 | s, (void *)t->addr, pr_time - t->when, t->cpu, t->pid); |
d6543e39 BG |
591 | #ifdef CONFIG_STACKTRACE |
592 | { | |
593 | int i; | |
594 | for (i = 0; i < TRACK_ADDRS_COUNT; i++) | |
595 | if (t->addrs[i]) | |
f9f58285 | 596 | pr_err("\t%pS\n", (void *)t->addrs[i]); |
d6543e39 BG |
597 | else |
598 | break; | |
599 | } | |
600 | #endif | |
24922684 CL |
601 | } |
602 | ||
603 | static void print_tracking(struct kmem_cache *s, void *object) | |
604 | { | |
86609d33 | 605 | unsigned long pr_time = jiffies; |
24922684 CL |
606 | if (!(s->flags & SLAB_STORE_USER)) |
607 | return; | |
608 | ||
86609d33 CP |
609 | print_track("Allocated", get_track(s, object, TRACK_ALLOC), pr_time); |
610 | print_track("Freed", get_track(s, object, TRACK_FREE), pr_time); | |
24922684 CL |
611 | } |
612 | ||
613 | static void print_page_info(struct page *page) | |
614 | { | |
f9f58285 | 615 | pr_err("INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n", |
d0e0ac97 | 616 | page, page->objects, page->inuse, page->freelist, page->flags); |
24922684 CL |
617 | |
618 | } | |
619 | ||
620 | static void slab_bug(struct kmem_cache *s, char *fmt, ...) | |
621 | { | |
ecc42fbe | 622 | struct va_format vaf; |
24922684 | 623 | va_list args; |
24922684 CL |
624 | |
625 | va_start(args, fmt); | |
ecc42fbe FF |
626 | vaf.fmt = fmt; |
627 | vaf.va = &args; | |
f9f58285 | 628 | pr_err("=============================================================================\n"); |
ecc42fbe | 629 | pr_err("BUG %s (%s): %pV\n", s->name, print_tainted(), &vaf); |
f9f58285 | 630 | pr_err("-----------------------------------------------------------------------------\n\n"); |
645df230 | 631 | |
373d4d09 | 632 | add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); |
ecc42fbe | 633 | va_end(args); |
81819f0f CL |
634 | } |
635 | ||
24922684 CL |
636 | static void slab_fix(struct kmem_cache *s, char *fmt, ...) |
637 | { | |
ecc42fbe | 638 | struct va_format vaf; |
24922684 | 639 | va_list args; |
24922684 CL |
640 | |
641 | va_start(args, fmt); | |
ecc42fbe FF |
642 | vaf.fmt = fmt; |
643 | vaf.va = &args; | |
644 | pr_err("FIX %s: %pV\n", s->name, &vaf); | |
24922684 | 645 | va_end(args); |
24922684 CL |
646 | } |
647 | ||
648 | static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) | |
81819f0f CL |
649 | { |
650 | unsigned int off; /* Offset of last byte */ | |
a973e9dd | 651 | u8 *addr = page_address(page); |
24922684 CL |
652 | |
653 | print_tracking(s, p); | |
654 | ||
655 | print_page_info(page); | |
656 | ||
f9f58285 FF |
657 | pr_err("INFO: Object 0x%p @offset=%tu fp=0x%p\n\n", |
658 | p, p - addr, get_freepointer(s, p)); | |
24922684 | 659 | |
d86bd1be | 660 | if (s->flags & SLAB_RED_ZONE) |
aa2efd5e DT |
661 | print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, |
662 | s->red_left_pad); | |
d86bd1be | 663 | else if (p > addr + 16) |
aa2efd5e | 664 | print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); |
81819f0f | 665 | |
aa2efd5e | 666 | print_section(KERN_ERR, "Object ", p, |
1b473f29 | 667 | min_t(unsigned int, s->object_size, PAGE_SIZE)); |
81819f0f | 668 | if (s->flags & SLAB_RED_ZONE) |
aa2efd5e | 669 | print_section(KERN_ERR, "Redzone ", p + s->object_size, |
3b0efdfa | 670 | s->inuse - s->object_size); |
81819f0f | 671 | |
81819f0f CL |
672 | if (s->offset) |
673 | off = s->offset + sizeof(void *); | |
674 | else | |
675 | off = s->inuse; | |
676 | ||
24922684 | 677 | if (s->flags & SLAB_STORE_USER) |
81819f0f | 678 | off += 2 * sizeof(struct track); |
81819f0f | 679 | |
80a9201a AP |
680 | off += kasan_metadata_size(s); |
681 | ||
d86bd1be | 682 | if (off != size_from_object(s)) |
81819f0f | 683 | /* Beginning of the filler is the free pointer */ |
aa2efd5e DT |
684 | print_section(KERN_ERR, "Padding ", p + off, |
685 | size_from_object(s) - off); | |
24922684 CL |
686 | |
687 | dump_stack(); | |
81819f0f CL |
688 | } |
689 | ||
75c66def | 690 | void object_err(struct kmem_cache *s, struct page *page, |
81819f0f CL |
691 | u8 *object, char *reason) |
692 | { | |
3dc50637 | 693 | slab_bug(s, "%s", reason); |
24922684 | 694 | print_trailer(s, page, object); |
81819f0f CL |
695 | } |
696 | ||
a38965bf | 697 | static __printf(3, 4) void slab_err(struct kmem_cache *s, struct page *page, |
d0e0ac97 | 698 | const char *fmt, ...) |
81819f0f CL |
699 | { |
700 | va_list args; | |
701 | char buf[100]; | |
702 | ||
24922684 CL |
703 | va_start(args, fmt); |
704 | vsnprintf(buf, sizeof(buf), fmt, args); | |
81819f0f | 705 | va_end(args); |
3dc50637 | 706 | slab_bug(s, "%s", buf); |
24922684 | 707 | print_page_info(page); |
81819f0f CL |
708 | dump_stack(); |
709 | } | |
710 | ||
f7cb1933 | 711 | static void init_object(struct kmem_cache *s, void *object, u8 val) |
81819f0f CL |
712 | { |
713 | u8 *p = object; | |
714 | ||
d86bd1be JK |
715 | if (s->flags & SLAB_RED_ZONE) |
716 | memset(p - s->red_left_pad, val, s->red_left_pad); | |
717 | ||
81819f0f | 718 | if (s->flags & __OBJECT_POISON) { |
3b0efdfa CL |
719 | memset(p, POISON_FREE, s->object_size - 1); |
720 | p[s->object_size - 1] = POISON_END; | |
81819f0f CL |
721 | } |
722 | ||
723 | if (s->flags & SLAB_RED_ZONE) | |
3b0efdfa | 724 | memset(p + s->object_size, val, s->inuse - s->object_size); |
81819f0f CL |
725 | } |
726 | ||
24922684 CL |
727 | static void restore_bytes(struct kmem_cache *s, char *message, u8 data, |
728 | void *from, void *to) | |
729 | { | |
730 | slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data); | |
731 | memset(from, data, to - from); | |
732 | } | |
733 | ||
734 | static int check_bytes_and_report(struct kmem_cache *s, struct page *page, | |
735 | u8 *object, char *what, | |
06428780 | 736 | u8 *start, unsigned int value, unsigned int bytes) |
24922684 CL |
737 | { |
738 | u8 *fault; | |
739 | u8 *end; | |
740 | ||
a79316c6 | 741 | metadata_access_enable(); |
79824820 | 742 | fault = memchr_inv(start, value, bytes); |
a79316c6 | 743 | metadata_access_disable(); |
24922684 CL |
744 | if (!fault) |
745 | return 1; | |
746 | ||
747 | end = start + bytes; | |
748 | while (end > fault && end[-1] == value) | |
749 | end--; | |
750 | ||
751 | slab_bug(s, "%s overwritten", what); | |
f9f58285 | 752 | pr_err("INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n", |
24922684 CL |
753 | fault, end - 1, fault[0], value); |
754 | print_trailer(s, page, object); | |
755 | ||
756 | restore_bytes(s, what, value, fault, end); | |
757 | return 0; | |
81819f0f CL |
758 | } |
759 | ||
81819f0f CL |
760 | /* |
761 | * Object layout: | |
762 | * | |
763 | * object address | |
764 | * Bytes of the object to be managed. | |
765 | * If the freepointer may overlay the object then the free | |
766 | * pointer is the first word of the object. | |
672bba3a | 767 | * |
81819f0f CL |
768 | * Poisoning uses 0x6b (POISON_FREE) and the last byte is |
769 | * 0xa5 (POISON_END) | |
770 | * | |
3b0efdfa | 771 | * object + s->object_size |
81819f0f | 772 | * Padding to reach word boundary. This is also used for Redzoning. |
672bba3a | 773 | * Padding is extended by another word if Redzoning is enabled and |
3b0efdfa | 774 | * object_size == inuse. |
672bba3a | 775 | * |
81819f0f CL |
776 | * We fill with 0xbb (RED_INACTIVE) for inactive objects and with |
777 | * 0xcc (RED_ACTIVE) for objects in use. | |
778 | * | |
779 | * object + s->inuse | |
672bba3a CL |
780 | * Meta data starts here. |
781 | * | |
81819f0f CL |
782 | * A. Free pointer (if we cannot overwrite object on free) |
783 | * B. Tracking data for SLAB_STORE_USER | |
672bba3a | 784 | * C. Padding to reach required alignment boundary or at mininum |
6446faa2 | 785 | * one word if debugging is on to be able to detect writes |
672bba3a CL |
786 | * before the word boundary. |
787 | * | |
788 | * Padding is done using 0x5a (POISON_INUSE) | |
81819f0f CL |
789 | * |
790 | * object + s->size | |
672bba3a | 791 | * Nothing is used beyond s->size. |
81819f0f | 792 | * |
3b0efdfa | 793 | * If slabcaches are merged then the object_size and inuse boundaries are mostly |
672bba3a | 794 | * ignored. And therefore no slab options that rely on these boundaries |
81819f0f CL |
795 | * may be used with merged slabcaches. |
796 | */ | |
797 | ||
81819f0f CL |
798 | static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) |
799 | { | |
800 | unsigned long off = s->inuse; /* The end of info */ | |
801 | ||
802 | if (s->offset) | |
803 | /* Freepointer is placed after the object. */ | |
804 | off += sizeof(void *); | |
805 | ||
806 | if (s->flags & SLAB_STORE_USER) | |
807 | /* We also have user information there */ | |
808 | off += 2 * sizeof(struct track); | |
809 | ||
80a9201a AP |
810 | off += kasan_metadata_size(s); |
811 | ||
d86bd1be | 812 | if (size_from_object(s) == off) |
81819f0f CL |
813 | return 1; |
814 | ||
24922684 | 815 | return check_bytes_and_report(s, page, p, "Object padding", |
d86bd1be | 816 | p + off, POISON_INUSE, size_from_object(s) - off); |
81819f0f CL |
817 | } |
818 | ||
39b26464 | 819 | /* Check the pad bytes at the end of a slab page */ |
81819f0f CL |
820 | static int slab_pad_check(struct kmem_cache *s, struct page *page) |
821 | { | |
24922684 CL |
822 | u8 *start; |
823 | u8 *fault; | |
824 | u8 *end; | |
5d682681 | 825 | u8 *pad; |
24922684 CL |
826 | int length; |
827 | int remainder; | |
81819f0f CL |
828 | |
829 | if (!(s->flags & SLAB_POISON)) | |
830 | return 1; | |
831 | ||
a973e9dd | 832 | start = page_address(page); |
9736d2a9 | 833 | length = PAGE_SIZE << compound_order(page); |
39b26464 CL |
834 | end = start + length; |
835 | remainder = length % s->size; | |
81819f0f CL |
836 | if (!remainder) |
837 | return 1; | |
838 | ||
5d682681 | 839 | pad = end - remainder; |
a79316c6 | 840 | metadata_access_enable(); |
5d682681 | 841 | fault = memchr_inv(pad, POISON_INUSE, remainder); |
a79316c6 | 842 | metadata_access_disable(); |
24922684 CL |
843 | if (!fault) |
844 | return 1; | |
845 | while (end > fault && end[-1] == POISON_INUSE) | |
846 | end--; | |
847 | ||
848 | slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); | |
5d682681 | 849 | print_section(KERN_ERR, "Padding ", pad, remainder); |
24922684 | 850 | |
5d682681 | 851 | restore_bytes(s, "slab padding", POISON_INUSE, fault, end); |
24922684 | 852 | return 0; |
81819f0f CL |
853 | } |
854 | ||
855 | static int check_object(struct kmem_cache *s, struct page *page, | |
f7cb1933 | 856 | void *object, u8 val) |
81819f0f CL |
857 | { |
858 | u8 *p = object; | |
3b0efdfa | 859 | u8 *endobject = object + s->object_size; |
81819f0f CL |
860 | |
861 | if (s->flags & SLAB_RED_ZONE) { | |
d86bd1be JK |
862 | if (!check_bytes_and_report(s, page, object, "Redzone", |
863 | object - s->red_left_pad, val, s->red_left_pad)) | |
864 | return 0; | |
865 | ||
24922684 | 866 | if (!check_bytes_and_report(s, page, object, "Redzone", |
3b0efdfa | 867 | endobject, val, s->inuse - s->object_size)) |
81819f0f | 868 | return 0; |
81819f0f | 869 | } else { |
3b0efdfa | 870 | if ((s->flags & SLAB_POISON) && s->object_size < s->inuse) { |
3adbefee | 871 | check_bytes_and_report(s, page, p, "Alignment padding", |
d0e0ac97 CG |
872 | endobject, POISON_INUSE, |
873 | s->inuse - s->object_size); | |
3adbefee | 874 | } |
81819f0f CL |
875 | } |
876 | ||
877 | if (s->flags & SLAB_POISON) { | |
f7cb1933 | 878 | if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) && |
24922684 | 879 | (!check_bytes_and_report(s, page, p, "Poison", p, |
3b0efdfa | 880 | POISON_FREE, s->object_size - 1) || |
24922684 | 881 | !check_bytes_and_report(s, page, p, "Poison", |
3b0efdfa | 882 | p + s->object_size - 1, POISON_END, 1))) |
81819f0f | 883 | return 0; |
81819f0f CL |
884 | /* |
885 | * check_pad_bytes cleans up on its own. | |
886 | */ | |
887 | check_pad_bytes(s, page, p); | |
888 | } | |
889 | ||
f7cb1933 | 890 | if (!s->offset && val == SLUB_RED_ACTIVE) |
81819f0f CL |
891 | /* |
892 | * Object and freepointer overlap. Cannot check | |
893 | * freepointer while object is allocated. | |
894 | */ | |
895 | return 1; | |
896 | ||
897 | /* Check free pointer validity */ | |
898 | if (!check_valid_pointer(s, page, get_freepointer(s, p))) { | |
899 | object_err(s, page, p, "Freepointer corrupt"); | |
900 | /* | |
9f6c708e | 901 | * No choice but to zap it and thus lose the remainder |
81819f0f | 902 | * of the free objects in this slab. May cause |
672bba3a | 903 | * another error because the object count is now wrong. |
81819f0f | 904 | */ |
a973e9dd | 905 | set_freepointer(s, p, NULL); |
81819f0f CL |
906 | return 0; |
907 | } | |
908 | return 1; | |
909 | } | |
910 | ||
911 | static int check_slab(struct kmem_cache *s, struct page *page) | |
912 | { | |
39b26464 CL |
913 | int maxobj; |
914 | ||
81819f0f CL |
915 | VM_BUG_ON(!irqs_disabled()); |
916 | ||
917 | if (!PageSlab(page)) { | |
24922684 | 918 | slab_err(s, page, "Not a valid slab page"); |
81819f0f CL |
919 | return 0; |
920 | } | |
39b26464 | 921 | |
9736d2a9 | 922 | maxobj = order_objects(compound_order(page), s->size); |
39b26464 CL |
923 | if (page->objects > maxobj) { |
924 | slab_err(s, page, "objects %u > max %u", | |
f6edde9c | 925 | page->objects, maxobj); |
39b26464 CL |
926 | return 0; |
927 | } | |
928 | if (page->inuse > page->objects) { | |
24922684 | 929 | slab_err(s, page, "inuse %u > max %u", |
f6edde9c | 930 | page->inuse, page->objects); |
81819f0f CL |
931 | return 0; |
932 | } | |
933 | /* Slab_pad_check fixes things up after itself */ | |
934 | slab_pad_check(s, page); | |
935 | return 1; | |
936 | } | |
937 | ||
938 | /* | |
672bba3a CL |
939 | * Determine if a certain object on a page is on the freelist. Must hold the |
940 | * slab lock to guarantee that the chains are in a consistent state. | |
81819f0f CL |
941 | */ |
942 | static int on_freelist(struct kmem_cache *s, struct page *page, void *search) | |
943 | { | |
944 | int nr = 0; | |
881db7fb | 945 | void *fp; |
81819f0f | 946 | void *object = NULL; |
f6edde9c | 947 | int max_objects; |
81819f0f | 948 | |
881db7fb | 949 | fp = page->freelist; |
39b26464 | 950 | while (fp && nr <= page->objects) { |
81819f0f CL |
951 | if (fp == search) |
952 | return 1; | |
953 | if (!check_valid_pointer(s, page, fp)) { | |
954 | if (object) { | |
955 | object_err(s, page, object, | |
956 | "Freechain corrupt"); | |
a973e9dd | 957 | set_freepointer(s, object, NULL); |
81819f0f | 958 | } else { |
24922684 | 959 | slab_err(s, page, "Freepointer corrupt"); |
a973e9dd | 960 | page->freelist = NULL; |
39b26464 | 961 | page->inuse = page->objects; |
24922684 | 962 | slab_fix(s, "Freelist cleared"); |
81819f0f CL |
963 | return 0; |
964 | } | |
965 | break; | |
966 | } | |
967 | object = fp; | |
968 | fp = get_freepointer(s, object); | |
969 | nr++; | |
970 | } | |
971 | ||
9736d2a9 | 972 | max_objects = order_objects(compound_order(page), s->size); |
210b5c06 CG |
973 | if (max_objects > MAX_OBJS_PER_PAGE) |
974 | max_objects = MAX_OBJS_PER_PAGE; | |
224a88be CL |
975 | |
976 | if (page->objects != max_objects) { | |
756a025f JP |
977 | slab_err(s, page, "Wrong number of objects. Found %d but should be %d", |
978 | page->objects, max_objects); | |
224a88be CL |
979 | page->objects = max_objects; |
980 | slab_fix(s, "Number of objects adjusted."); | |
981 | } | |
39b26464 | 982 | if (page->inuse != page->objects - nr) { |
756a025f JP |
983 | slab_err(s, page, "Wrong object count. Counter is %d but counted were %d", |
984 | page->inuse, page->objects - nr); | |
39b26464 | 985 | page->inuse = page->objects - nr; |
24922684 | 986 | slab_fix(s, "Object count adjusted."); |
81819f0f CL |
987 | } |
988 | return search == NULL; | |
989 | } | |
990 | ||
0121c619 CL |
991 | static void trace(struct kmem_cache *s, struct page *page, void *object, |
992 | int alloc) | |
3ec09742 CL |
993 | { |
994 | if (s->flags & SLAB_TRACE) { | |
f9f58285 | 995 | pr_info("TRACE %s %s 0x%p inuse=%d fp=0x%p\n", |
3ec09742 CL |
996 | s->name, |
997 | alloc ? "alloc" : "free", | |
998 | object, page->inuse, | |
999 | page->freelist); | |
1000 | ||
1001 | if (!alloc) | |
aa2efd5e | 1002 | print_section(KERN_INFO, "Object ", (void *)object, |
d0e0ac97 | 1003 | s->object_size); |
3ec09742 CL |
1004 | |
1005 | dump_stack(); | |
1006 | } | |
1007 | } | |
1008 | ||
643b1138 | 1009 | /* |
672bba3a | 1010 | * Tracking of fully allocated slabs for debugging purposes. |
643b1138 | 1011 | */ |
5cc6eee8 CL |
1012 | static void add_full(struct kmem_cache *s, |
1013 | struct kmem_cache_node *n, struct page *page) | |
643b1138 | 1014 | { |
5cc6eee8 CL |
1015 | if (!(s->flags & SLAB_STORE_USER)) |
1016 | return; | |
1017 | ||
255d0884 | 1018 | lockdep_assert_held(&n->list_lock); |
643b1138 | 1019 | list_add(&page->lru, &n->full); |
643b1138 CL |
1020 | } |
1021 | ||
c65c1877 | 1022 | static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct page *page) |
643b1138 | 1023 | { |
643b1138 CL |
1024 | if (!(s->flags & SLAB_STORE_USER)) |
1025 | return; | |
1026 | ||
255d0884 | 1027 | lockdep_assert_held(&n->list_lock); |
643b1138 | 1028 | list_del(&page->lru); |
643b1138 CL |
1029 | } |
1030 | ||
0f389ec6 CL |
1031 | /* Tracking of the number of slabs for debugging purposes */ |
1032 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) | |
1033 | { | |
1034 | struct kmem_cache_node *n = get_node(s, node); | |
1035 | ||
1036 | return atomic_long_read(&n->nr_slabs); | |
1037 | } | |
1038 | ||
26c02cf0 AB |
1039 | static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) |
1040 | { | |
1041 | return atomic_long_read(&n->nr_slabs); | |
1042 | } | |
1043 | ||
205ab99d | 1044 | static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
1045 | { |
1046 | struct kmem_cache_node *n = get_node(s, node); | |
1047 | ||
1048 | /* | |
1049 | * May be called early in order to allocate a slab for the | |
1050 | * kmem_cache_node structure. Solve the chicken-egg | |
1051 | * dilemma by deferring the increment of the count during | |
1052 | * bootstrap (see early_kmem_cache_node_alloc). | |
1053 | */ | |
338b2642 | 1054 | if (likely(n)) { |
0f389ec6 | 1055 | atomic_long_inc(&n->nr_slabs); |
205ab99d CL |
1056 | atomic_long_add(objects, &n->total_objects); |
1057 | } | |
0f389ec6 | 1058 | } |
205ab99d | 1059 | static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
1060 | { |
1061 | struct kmem_cache_node *n = get_node(s, node); | |
1062 | ||
1063 | atomic_long_dec(&n->nr_slabs); | |
205ab99d | 1064 | atomic_long_sub(objects, &n->total_objects); |
0f389ec6 CL |
1065 | } |
1066 | ||
1067 | /* Object debug checks for alloc/free paths */ | |
3ec09742 CL |
1068 | static void setup_object_debug(struct kmem_cache *s, struct page *page, |
1069 | void *object) | |
1070 | { | |
1071 | if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON))) | |
1072 | return; | |
1073 | ||
f7cb1933 | 1074 | init_object(s, object, SLUB_RED_INACTIVE); |
3ec09742 CL |
1075 | init_tracking(s, object); |
1076 | } | |
1077 | ||
a7101224 AK |
1078 | static void setup_page_debug(struct kmem_cache *s, void *addr, int order) |
1079 | { | |
1080 | if (!(s->flags & SLAB_POISON)) | |
1081 | return; | |
1082 | ||
1083 | metadata_access_enable(); | |
1084 | memset(addr, POISON_INUSE, PAGE_SIZE << order); | |
1085 | metadata_access_disable(); | |
1086 | } | |
1087 | ||
becfda68 | 1088 | static inline int alloc_consistency_checks(struct kmem_cache *s, |
d0e0ac97 | 1089 | struct page *page, |
ce71e27c | 1090 | void *object, unsigned long addr) |
81819f0f CL |
1091 | { |
1092 | if (!check_slab(s, page)) | |
becfda68 | 1093 | return 0; |
81819f0f | 1094 | |
81819f0f CL |
1095 | if (!check_valid_pointer(s, page, object)) { |
1096 | object_err(s, page, object, "Freelist Pointer check fails"); | |
becfda68 | 1097 | return 0; |
81819f0f CL |
1098 | } |
1099 | ||
f7cb1933 | 1100 | if (!check_object(s, page, object, SLUB_RED_INACTIVE)) |
becfda68 LA |
1101 | return 0; |
1102 | ||
1103 | return 1; | |
1104 | } | |
1105 | ||
1106 | static noinline int alloc_debug_processing(struct kmem_cache *s, | |
1107 | struct page *page, | |
1108 | void *object, unsigned long addr) | |
1109 | { | |
1110 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { | |
1111 | if (!alloc_consistency_checks(s, page, object, addr)) | |
1112 | goto bad; | |
1113 | } | |
81819f0f | 1114 | |
3ec09742 CL |
1115 | /* Success perform special debug activities for allocs */ |
1116 | if (s->flags & SLAB_STORE_USER) | |
1117 | set_track(s, object, TRACK_ALLOC, addr); | |
1118 | trace(s, page, object, 1); | |
f7cb1933 | 1119 | init_object(s, object, SLUB_RED_ACTIVE); |
81819f0f | 1120 | return 1; |
3ec09742 | 1121 | |
81819f0f CL |
1122 | bad: |
1123 | if (PageSlab(page)) { | |
1124 | /* | |
1125 | * If this is a slab page then lets do the best we can | |
1126 | * to avoid issues in the future. Marking all objects | |
672bba3a | 1127 | * as used avoids touching the remaining objects. |
81819f0f | 1128 | */ |
24922684 | 1129 | slab_fix(s, "Marking all objects used"); |
39b26464 | 1130 | page->inuse = page->objects; |
a973e9dd | 1131 | page->freelist = NULL; |
81819f0f CL |
1132 | } |
1133 | return 0; | |
1134 | } | |
1135 | ||
becfda68 LA |
1136 | static inline int free_consistency_checks(struct kmem_cache *s, |
1137 | struct page *page, void *object, unsigned long addr) | |
81819f0f | 1138 | { |
81819f0f | 1139 | if (!check_valid_pointer(s, page, object)) { |
70d71228 | 1140 | slab_err(s, page, "Invalid object pointer 0x%p", object); |
becfda68 | 1141 | return 0; |
81819f0f CL |
1142 | } |
1143 | ||
1144 | if (on_freelist(s, page, object)) { | |
24922684 | 1145 | object_err(s, page, object, "Object already free"); |
becfda68 | 1146 | return 0; |
81819f0f CL |
1147 | } |
1148 | ||
f7cb1933 | 1149 | if (!check_object(s, page, object, SLUB_RED_ACTIVE)) |
becfda68 | 1150 | return 0; |
81819f0f | 1151 | |
1b4f59e3 | 1152 | if (unlikely(s != page->slab_cache)) { |
3adbefee | 1153 | if (!PageSlab(page)) { |
756a025f JP |
1154 | slab_err(s, page, "Attempt to free object(0x%p) outside of slab", |
1155 | object); | |
1b4f59e3 | 1156 | } else if (!page->slab_cache) { |
f9f58285 FF |
1157 | pr_err("SLUB <none>: no slab for object 0x%p.\n", |
1158 | object); | |
70d71228 | 1159 | dump_stack(); |
06428780 | 1160 | } else |
24922684 CL |
1161 | object_err(s, page, object, |
1162 | "page slab pointer corrupt."); | |
becfda68 LA |
1163 | return 0; |
1164 | } | |
1165 | return 1; | |
1166 | } | |
1167 | ||
1168 | /* Supports checking bulk free of a constructed freelist */ | |
1169 | static noinline int free_debug_processing( | |
1170 | struct kmem_cache *s, struct page *page, | |
1171 | void *head, void *tail, int bulk_cnt, | |
1172 | unsigned long addr) | |
1173 | { | |
1174 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); | |
1175 | void *object = head; | |
1176 | int cnt = 0; | |
1177 | unsigned long uninitialized_var(flags); | |
1178 | int ret = 0; | |
1179 | ||
1180 | spin_lock_irqsave(&n->list_lock, flags); | |
1181 | slab_lock(page); | |
1182 | ||
1183 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { | |
1184 | if (!check_slab(s, page)) | |
1185 | goto out; | |
1186 | } | |
1187 | ||
1188 | next_object: | |
1189 | cnt++; | |
1190 | ||
1191 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { | |
1192 | if (!free_consistency_checks(s, page, object, addr)) | |
1193 | goto out; | |
81819f0f | 1194 | } |
3ec09742 | 1195 | |
3ec09742 CL |
1196 | if (s->flags & SLAB_STORE_USER) |
1197 | set_track(s, object, TRACK_FREE, addr); | |
1198 | trace(s, page, object, 0); | |
81084651 | 1199 | /* Freepointer not overwritten by init_object(), SLAB_POISON moved it */ |
f7cb1933 | 1200 | init_object(s, object, SLUB_RED_INACTIVE); |
81084651 JDB |
1201 | |
1202 | /* Reached end of constructed freelist yet? */ | |
1203 | if (object != tail) { | |
1204 | object = get_freepointer(s, object); | |
1205 | goto next_object; | |
1206 | } | |
804aa132 LA |
1207 | ret = 1; |
1208 | ||
5c2e4bbb | 1209 | out: |
81084651 JDB |
1210 | if (cnt != bulk_cnt) |
1211 | slab_err(s, page, "Bulk freelist count(%d) invalid(%d)\n", | |
1212 | bulk_cnt, cnt); | |
1213 | ||
881db7fb | 1214 | slab_unlock(page); |
282acb43 | 1215 | spin_unlock_irqrestore(&n->list_lock, flags); |
804aa132 LA |
1216 | if (!ret) |
1217 | slab_fix(s, "Object at 0x%p not freed", object); | |
1218 | return ret; | |
81819f0f CL |
1219 | } |
1220 | ||
41ecc55b CL |
1221 | static int __init setup_slub_debug(char *str) |
1222 | { | |
f0630fff CL |
1223 | slub_debug = DEBUG_DEFAULT_FLAGS; |
1224 | if (*str++ != '=' || !*str) | |
1225 | /* | |
1226 | * No options specified. Switch on full debugging. | |
1227 | */ | |
1228 | goto out; | |
1229 | ||
1230 | if (*str == ',') | |
1231 | /* | |
1232 | * No options but restriction on slabs. This means full | |
1233 | * debugging for slabs matching a pattern. | |
1234 | */ | |
1235 | goto check_slabs; | |
1236 | ||
1237 | slub_debug = 0; | |
1238 | if (*str == '-') | |
1239 | /* | |
1240 | * Switch off all debugging measures. | |
1241 | */ | |
1242 | goto out; | |
1243 | ||
1244 | /* | |
1245 | * Determine which debug features should be switched on | |
1246 | */ | |
06428780 | 1247 | for (; *str && *str != ','; str++) { |
f0630fff CL |
1248 | switch (tolower(*str)) { |
1249 | case 'f': | |
becfda68 | 1250 | slub_debug |= SLAB_CONSISTENCY_CHECKS; |
f0630fff CL |
1251 | break; |
1252 | case 'z': | |
1253 | slub_debug |= SLAB_RED_ZONE; | |
1254 | break; | |
1255 | case 'p': | |
1256 | slub_debug |= SLAB_POISON; | |
1257 | break; | |
1258 | case 'u': | |
1259 | slub_debug |= SLAB_STORE_USER; | |
1260 | break; | |
1261 | case 't': | |
1262 | slub_debug |= SLAB_TRACE; | |
1263 | break; | |
4c13dd3b DM |
1264 | case 'a': |
1265 | slub_debug |= SLAB_FAILSLAB; | |
1266 | break; | |
08303a73 CA |
1267 | case 'o': |
1268 | /* | |
1269 | * Avoid enabling debugging on caches if its minimum | |
1270 | * order would increase as a result. | |
1271 | */ | |
1272 | disable_higher_order_debug = 1; | |
1273 | break; | |
f0630fff | 1274 | default: |
f9f58285 FF |
1275 | pr_err("slub_debug option '%c' unknown. skipped\n", |
1276 | *str); | |
f0630fff | 1277 | } |
41ecc55b CL |
1278 | } |
1279 | ||
f0630fff | 1280 | check_slabs: |
41ecc55b CL |
1281 | if (*str == ',') |
1282 | slub_debug_slabs = str + 1; | |
f0630fff | 1283 | out: |
41ecc55b CL |
1284 | return 1; |
1285 | } | |
1286 | ||
1287 | __setup("slub_debug", setup_slub_debug); | |
1288 | ||
c5fd3ca0 AT |
1289 | /* |
1290 | * kmem_cache_flags - apply debugging options to the cache | |
1291 | * @object_size: the size of an object without meta data | |
1292 | * @flags: flags to set | |
1293 | * @name: name of the cache | |
1294 | * @ctor: constructor function | |
1295 | * | |
1296 | * Debug option(s) are applied to @flags. In addition to the debug | |
1297 | * option(s), if a slab name (or multiple) is specified i.e. | |
1298 | * slub_debug=<Debug-Options>,<slab name1>,<slab name2> ... | |
1299 | * then only the select slabs will receive the debug option(s). | |
1300 | */ | |
0293d1fd | 1301 | slab_flags_t kmem_cache_flags(unsigned int object_size, |
d50112ed | 1302 | slab_flags_t flags, const char *name, |
51cc5068 | 1303 | void (*ctor)(void *)) |
41ecc55b | 1304 | { |
c5fd3ca0 AT |
1305 | char *iter; |
1306 | size_t len; | |
1307 | ||
1308 | /* If slub_debug = 0, it folds into the if conditional. */ | |
1309 | if (!slub_debug_slabs) | |
1310 | return flags | slub_debug; | |
1311 | ||
1312 | len = strlen(name); | |
1313 | iter = slub_debug_slabs; | |
1314 | while (*iter) { | |
1315 | char *end, *glob; | |
1316 | size_t cmplen; | |
1317 | ||
1318 | end = strchr(iter, ','); | |
1319 | if (!end) | |
1320 | end = iter + strlen(iter); | |
1321 | ||
1322 | glob = strnchr(iter, end - iter, '*'); | |
1323 | if (glob) | |
1324 | cmplen = glob - iter; | |
1325 | else | |
1326 | cmplen = max_t(size_t, len, (end - iter)); | |
1327 | ||
1328 | if (!strncmp(name, iter, cmplen)) { | |
1329 | flags |= slub_debug; | |
1330 | break; | |
1331 | } | |
1332 | ||
1333 | if (!*end) | |
1334 | break; | |
1335 | iter = end + 1; | |
1336 | } | |
ba0268a8 CL |
1337 | |
1338 | return flags; | |
41ecc55b | 1339 | } |
b4a64718 | 1340 | #else /* !CONFIG_SLUB_DEBUG */ |
3ec09742 CL |
1341 | static inline void setup_object_debug(struct kmem_cache *s, |
1342 | struct page *page, void *object) {} | |
a7101224 AK |
1343 | static inline void setup_page_debug(struct kmem_cache *s, |
1344 | void *addr, int order) {} | |
41ecc55b | 1345 | |
3ec09742 | 1346 | static inline int alloc_debug_processing(struct kmem_cache *s, |
ce71e27c | 1347 | struct page *page, void *object, unsigned long addr) { return 0; } |
41ecc55b | 1348 | |
282acb43 | 1349 | static inline int free_debug_processing( |
81084651 JDB |
1350 | struct kmem_cache *s, struct page *page, |
1351 | void *head, void *tail, int bulk_cnt, | |
282acb43 | 1352 | unsigned long addr) { return 0; } |
41ecc55b | 1353 | |
41ecc55b CL |
1354 | static inline int slab_pad_check(struct kmem_cache *s, struct page *page) |
1355 | { return 1; } | |
1356 | static inline int check_object(struct kmem_cache *s, struct page *page, | |
f7cb1933 | 1357 | void *object, u8 val) { return 1; } |
5cc6eee8 CL |
1358 | static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n, |
1359 | struct page *page) {} | |
c65c1877 PZ |
1360 | static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, |
1361 | struct page *page) {} | |
0293d1fd | 1362 | slab_flags_t kmem_cache_flags(unsigned int object_size, |
d50112ed | 1363 | slab_flags_t flags, const char *name, |
51cc5068 | 1364 | void (*ctor)(void *)) |
ba0268a8 CL |
1365 | { |
1366 | return flags; | |
1367 | } | |
41ecc55b | 1368 | #define slub_debug 0 |
0f389ec6 | 1369 | |
fdaa45e9 IM |
1370 | #define disable_higher_order_debug 0 |
1371 | ||
0f389ec6 CL |
1372 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) |
1373 | { return 0; } | |
26c02cf0 AB |
1374 | static inline unsigned long node_nr_slabs(struct kmem_cache_node *n) |
1375 | { return 0; } | |
205ab99d CL |
1376 | static inline void inc_slabs_node(struct kmem_cache *s, int node, |
1377 | int objects) {} | |
1378 | static inline void dec_slabs_node(struct kmem_cache *s, int node, | |
1379 | int objects) {} | |
7d550c56 | 1380 | |
02e72cc6 AR |
1381 | #endif /* CONFIG_SLUB_DEBUG */ |
1382 | ||
1383 | /* | |
1384 | * Hooks for other subsystems that check memory allocations. In a typical | |
1385 | * production configuration these hooks all should produce no code at all. | |
1386 | */ | |
0116523c | 1387 | static inline void *kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags) |
d56791b3 | 1388 | { |
53128245 | 1389 | ptr = kasan_kmalloc_large(ptr, size, flags); |
a2f77575 | 1390 | /* As ptr might get tagged, call kmemleak hook after KASAN. */ |
d56791b3 | 1391 | kmemleak_alloc(ptr, size, 1, flags); |
53128245 | 1392 | return ptr; |
d56791b3 RB |
1393 | } |
1394 | ||
ee3ce779 | 1395 | static __always_inline void kfree_hook(void *x) |
d56791b3 RB |
1396 | { |
1397 | kmemleak_free(x); | |
ee3ce779 | 1398 | kasan_kfree_large(x, _RET_IP_); |
d56791b3 RB |
1399 | } |
1400 | ||
c3895391 | 1401 | static __always_inline bool slab_free_hook(struct kmem_cache *s, void *x) |
d56791b3 RB |
1402 | { |
1403 | kmemleak_free_recursive(x, s->flags); | |
7d550c56 | 1404 | |
02e72cc6 AR |
1405 | /* |
1406 | * Trouble is that we may no longer disable interrupts in the fast path | |
1407 | * So in order to make the debug calls that expect irqs to be | |
1408 | * disabled we need to disable interrupts temporarily. | |
1409 | */ | |
4675ff05 | 1410 | #ifdef CONFIG_LOCKDEP |
02e72cc6 AR |
1411 | { |
1412 | unsigned long flags; | |
1413 | ||
1414 | local_irq_save(flags); | |
02e72cc6 AR |
1415 | debug_check_no_locks_freed(x, s->object_size); |
1416 | local_irq_restore(flags); | |
1417 | } | |
1418 | #endif | |
1419 | if (!(s->flags & SLAB_DEBUG_OBJECTS)) | |
1420 | debug_check_no_obj_freed(x, s->object_size); | |
0316bec2 | 1421 | |
c3895391 AK |
1422 | /* KASAN might put x into memory quarantine, delaying its reuse */ |
1423 | return kasan_slab_free(s, x, _RET_IP_); | |
02e72cc6 | 1424 | } |
205ab99d | 1425 | |
c3895391 AK |
1426 | static inline bool slab_free_freelist_hook(struct kmem_cache *s, |
1427 | void **head, void **tail) | |
81084651 JDB |
1428 | { |
1429 | /* | |
1430 | * Compiler cannot detect this function can be removed if slab_free_hook() | |
1431 | * evaluates to nothing. Thus, catch all relevant config debug options here. | |
1432 | */ | |
4675ff05 | 1433 | #if defined(CONFIG_LOCKDEP) || \ |
81084651 JDB |
1434 | defined(CONFIG_DEBUG_KMEMLEAK) || \ |
1435 | defined(CONFIG_DEBUG_OBJECTS_FREE) || \ | |
1436 | defined(CONFIG_KASAN) | |
1437 | ||
c3895391 AK |
1438 | void *object; |
1439 | void *next = *head; | |
1440 | void *old_tail = *tail ? *tail : *head; | |
1441 | ||
1442 | /* Head and tail of the reconstructed freelist */ | |
1443 | *head = NULL; | |
1444 | *tail = NULL; | |
81084651 JDB |
1445 | |
1446 | do { | |
c3895391 AK |
1447 | object = next; |
1448 | next = get_freepointer(s, object); | |
1449 | /* If object's reuse doesn't have to be delayed */ | |
1450 | if (!slab_free_hook(s, object)) { | |
1451 | /* Move object to the new freelist */ | |
1452 | set_freepointer(s, object, *head); | |
1453 | *head = object; | |
1454 | if (!*tail) | |
1455 | *tail = object; | |
1456 | } | |
1457 | } while (object != old_tail); | |
1458 | ||
1459 | if (*head == *tail) | |
1460 | *tail = NULL; | |
1461 | ||
1462 | return *head != NULL; | |
1463 | #else | |
1464 | return true; | |
81084651 JDB |
1465 | #endif |
1466 | } | |
1467 | ||
4d176711 | 1468 | static void *setup_object(struct kmem_cache *s, struct page *page, |
588f8ba9 TG |
1469 | void *object) |
1470 | { | |
1471 | setup_object_debug(s, page, object); | |
4d176711 | 1472 | object = kasan_init_slab_obj(s, object); |
588f8ba9 TG |
1473 | if (unlikely(s->ctor)) { |
1474 | kasan_unpoison_object_data(s, object); | |
1475 | s->ctor(object); | |
1476 | kasan_poison_object_data(s, object); | |
1477 | } | |
4d176711 | 1478 | return object; |
588f8ba9 TG |
1479 | } |
1480 | ||
81819f0f CL |
1481 | /* |
1482 | * Slab allocation and freeing | |
1483 | */ | |
5dfb4175 VD |
1484 | static inline struct page *alloc_slab_page(struct kmem_cache *s, |
1485 | gfp_t flags, int node, struct kmem_cache_order_objects oo) | |
65c3376a | 1486 | { |
5dfb4175 | 1487 | struct page *page; |
19af27af | 1488 | unsigned int order = oo_order(oo); |
65c3376a | 1489 | |
2154a336 | 1490 | if (node == NUMA_NO_NODE) |
5dfb4175 | 1491 | page = alloc_pages(flags, order); |
65c3376a | 1492 | else |
96db800f | 1493 | page = __alloc_pages_node(node, flags, order); |
5dfb4175 | 1494 | |
f3ccb2c4 VD |
1495 | if (page && memcg_charge_slab(page, flags, order, s)) { |
1496 | __free_pages(page, order); | |
1497 | page = NULL; | |
1498 | } | |
5dfb4175 VD |
1499 | |
1500 | return page; | |
65c3376a CL |
1501 | } |
1502 | ||
210e7a43 TG |
1503 | #ifdef CONFIG_SLAB_FREELIST_RANDOM |
1504 | /* Pre-initialize the random sequence cache */ | |
1505 | static int init_cache_random_seq(struct kmem_cache *s) | |
1506 | { | |
19af27af | 1507 | unsigned int count = oo_objects(s->oo); |
210e7a43 | 1508 | int err; |
210e7a43 | 1509 | |
a810007a SR |
1510 | /* Bailout if already initialised */ |
1511 | if (s->random_seq) | |
1512 | return 0; | |
1513 | ||
210e7a43 TG |
1514 | err = cache_random_seq_create(s, count, GFP_KERNEL); |
1515 | if (err) { | |
1516 | pr_err("SLUB: Unable to initialize free list for %s\n", | |
1517 | s->name); | |
1518 | return err; | |
1519 | } | |
1520 | ||
1521 | /* Transform to an offset on the set of pages */ | |
1522 | if (s->random_seq) { | |
19af27af AD |
1523 | unsigned int i; |
1524 | ||
210e7a43 TG |
1525 | for (i = 0; i < count; i++) |
1526 | s->random_seq[i] *= s->size; | |
1527 | } | |
1528 | return 0; | |
1529 | } | |
1530 | ||
1531 | /* Initialize each random sequence freelist per cache */ | |
1532 | static void __init init_freelist_randomization(void) | |
1533 | { | |
1534 | struct kmem_cache *s; | |
1535 | ||
1536 | mutex_lock(&slab_mutex); | |
1537 | ||
1538 | list_for_each_entry(s, &slab_caches, list) | |
1539 | init_cache_random_seq(s); | |
1540 | ||
1541 | mutex_unlock(&slab_mutex); | |
1542 | } | |
1543 | ||
1544 | /* Get the next entry on the pre-computed freelist randomized */ | |
1545 | static void *next_freelist_entry(struct kmem_cache *s, struct page *page, | |
1546 | unsigned long *pos, void *start, | |
1547 | unsigned long page_limit, | |
1548 | unsigned long freelist_count) | |
1549 | { | |
1550 | unsigned int idx; | |
1551 | ||
1552 | /* | |
1553 | * If the target page allocation failed, the number of objects on the | |
1554 | * page might be smaller than the usual size defined by the cache. | |
1555 | */ | |
1556 | do { | |
1557 | idx = s->random_seq[*pos]; | |
1558 | *pos += 1; | |
1559 | if (*pos >= freelist_count) | |
1560 | *pos = 0; | |
1561 | } while (unlikely(idx >= page_limit)); | |
1562 | ||
1563 | return (char *)start + idx; | |
1564 | } | |
1565 | ||
1566 | /* Shuffle the single linked freelist based on a random pre-computed sequence */ | |
1567 | static bool shuffle_freelist(struct kmem_cache *s, struct page *page) | |
1568 | { | |
1569 | void *start; | |
1570 | void *cur; | |
1571 | void *next; | |
1572 | unsigned long idx, pos, page_limit, freelist_count; | |
1573 | ||
1574 | if (page->objects < 2 || !s->random_seq) | |
1575 | return false; | |
1576 | ||
1577 | freelist_count = oo_objects(s->oo); | |
1578 | pos = get_random_int() % freelist_count; | |
1579 | ||
1580 | page_limit = page->objects * s->size; | |
1581 | start = fixup_red_left(s, page_address(page)); | |
1582 | ||
1583 | /* First entry is used as the base of the freelist */ | |
1584 | cur = next_freelist_entry(s, page, &pos, start, page_limit, | |
1585 | freelist_count); | |
4d176711 | 1586 | cur = setup_object(s, page, cur); |
210e7a43 TG |
1587 | page->freelist = cur; |
1588 | ||
1589 | for (idx = 1; idx < page->objects; idx++) { | |
210e7a43 TG |
1590 | next = next_freelist_entry(s, page, &pos, start, page_limit, |
1591 | freelist_count); | |
4d176711 | 1592 | next = setup_object(s, page, next); |
210e7a43 TG |
1593 | set_freepointer(s, cur, next); |
1594 | cur = next; | |
1595 | } | |
210e7a43 TG |
1596 | set_freepointer(s, cur, NULL); |
1597 | ||
1598 | return true; | |
1599 | } | |
1600 | #else | |
1601 | static inline int init_cache_random_seq(struct kmem_cache *s) | |
1602 | { | |
1603 | return 0; | |
1604 | } | |
1605 | static inline void init_freelist_randomization(void) { } | |
1606 | static inline bool shuffle_freelist(struct kmem_cache *s, struct page *page) | |
1607 | { | |
1608 | return false; | |
1609 | } | |
1610 | #endif /* CONFIG_SLAB_FREELIST_RANDOM */ | |
1611 | ||
81819f0f CL |
1612 | static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) |
1613 | { | |
06428780 | 1614 | struct page *page; |
834f3d11 | 1615 | struct kmem_cache_order_objects oo = s->oo; |
ba52270d | 1616 | gfp_t alloc_gfp; |
4d176711 | 1617 | void *start, *p, *next; |
588f8ba9 | 1618 | int idx, order; |
210e7a43 | 1619 | bool shuffle; |
81819f0f | 1620 | |
7e0528da CL |
1621 | flags &= gfp_allowed_mask; |
1622 | ||
d0164adc | 1623 | if (gfpflags_allow_blocking(flags)) |
7e0528da CL |
1624 | local_irq_enable(); |
1625 | ||
b7a49f0d | 1626 | flags |= s->allocflags; |
e12ba74d | 1627 | |
ba52270d PE |
1628 | /* |
1629 | * Let the initial higher-order allocation fail under memory pressure | |
1630 | * so we fall-back to the minimum order allocation. | |
1631 | */ | |
1632 | alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL; | |
d0164adc | 1633 | if ((alloc_gfp & __GFP_DIRECT_RECLAIM) && oo_order(oo) > oo_order(s->min)) |
444eb2a4 | 1634 | alloc_gfp = (alloc_gfp | __GFP_NOMEMALLOC) & ~(__GFP_RECLAIM|__GFP_NOFAIL); |
ba52270d | 1635 | |
5dfb4175 | 1636 | page = alloc_slab_page(s, alloc_gfp, node, oo); |
65c3376a CL |
1637 | if (unlikely(!page)) { |
1638 | oo = s->min; | |
80c3a998 | 1639 | alloc_gfp = flags; |
65c3376a CL |
1640 | /* |
1641 | * Allocation may have failed due to fragmentation. | |
1642 | * Try a lower order alloc if possible | |
1643 | */ | |
5dfb4175 | 1644 | page = alloc_slab_page(s, alloc_gfp, node, oo); |
588f8ba9 TG |
1645 | if (unlikely(!page)) |
1646 | goto out; | |
1647 | stat(s, ORDER_FALLBACK); | |
65c3376a | 1648 | } |
5a896d9e | 1649 | |
834f3d11 | 1650 | page->objects = oo_objects(oo); |
81819f0f | 1651 | |
1f458cbf | 1652 | order = compound_order(page); |
1b4f59e3 | 1653 | page->slab_cache = s; |
c03f94cc | 1654 | __SetPageSlab(page); |
2f064f34 | 1655 | if (page_is_pfmemalloc(page)) |
072bb0aa | 1656 | SetPageSlabPfmemalloc(page); |
81819f0f | 1657 | |
a7101224 | 1658 | kasan_poison_slab(page); |
81819f0f | 1659 | |
a7101224 | 1660 | start = page_address(page); |
81819f0f | 1661 | |
a7101224 | 1662 | setup_page_debug(s, start, order); |
0316bec2 | 1663 | |
210e7a43 TG |
1664 | shuffle = shuffle_freelist(s, page); |
1665 | ||
1666 | if (!shuffle) { | |
1667 | for_each_object_idx(p, idx, s, start, page->objects) { | |
4d176711 AK |
1668 | if (likely(idx < page->objects)) { |
1669 | next = p + s->size; | |
1670 | next = setup_object(s, page, next); | |
1671 | set_freepointer(s, p, next); | |
1672 | } else | |
210e7a43 TG |
1673 | set_freepointer(s, p, NULL); |
1674 | } | |
4d176711 AK |
1675 | start = fixup_red_left(s, start); |
1676 | start = setup_object(s, page, start); | |
1677 | page->freelist = start; | |
81819f0f | 1678 | } |
81819f0f | 1679 | |
e6e82ea1 | 1680 | page->inuse = page->objects; |
8cb0a506 | 1681 | page->frozen = 1; |
588f8ba9 | 1682 | |
81819f0f | 1683 | out: |
d0164adc | 1684 | if (gfpflags_allow_blocking(flags)) |
588f8ba9 TG |
1685 | local_irq_disable(); |
1686 | if (!page) | |
1687 | return NULL; | |
1688 | ||
7779f212 | 1689 | mod_lruvec_page_state(page, |
588f8ba9 TG |
1690 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? |
1691 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
1692 | 1 << oo_order(oo)); | |
1693 | ||
1694 | inc_slabs_node(s, page_to_nid(page), page->objects); | |
1695 | ||
81819f0f CL |
1696 | return page; |
1697 | } | |
1698 | ||
588f8ba9 TG |
1699 | static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) |
1700 | { | |
1701 | if (unlikely(flags & GFP_SLAB_BUG_MASK)) { | |
bacdcb34 | 1702 | gfp_t invalid_mask = flags & GFP_SLAB_BUG_MASK; |
72baeef0 MH |
1703 | flags &= ~GFP_SLAB_BUG_MASK; |
1704 | pr_warn("Unexpected gfp: %#x (%pGg). Fixing up to gfp: %#x (%pGg). Fix your code!\n", | |
1705 | invalid_mask, &invalid_mask, flags, &flags); | |
65b9de75 | 1706 | dump_stack(); |
588f8ba9 TG |
1707 | } |
1708 | ||
1709 | return allocate_slab(s, | |
1710 | flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); | |
1711 | } | |
1712 | ||
81819f0f CL |
1713 | static void __free_slab(struct kmem_cache *s, struct page *page) |
1714 | { | |
834f3d11 CL |
1715 | int order = compound_order(page); |
1716 | int pages = 1 << order; | |
81819f0f | 1717 | |
becfda68 | 1718 | if (s->flags & SLAB_CONSISTENCY_CHECKS) { |
81819f0f CL |
1719 | void *p; |
1720 | ||
1721 | slab_pad_check(s, page); | |
224a88be CL |
1722 | for_each_object(p, s, page_address(page), |
1723 | page->objects) | |
f7cb1933 | 1724 | check_object(s, page, p, SLUB_RED_INACTIVE); |
81819f0f CL |
1725 | } |
1726 | ||
7779f212 | 1727 | mod_lruvec_page_state(page, |
81819f0f CL |
1728 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? |
1729 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
06428780 | 1730 | -pages); |
81819f0f | 1731 | |
072bb0aa | 1732 | __ClearPageSlabPfmemalloc(page); |
49bd5221 | 1733 | __ClearPageSlab(page); |
1f458cbf | 1734 | |
d4fc5069 | 1735 | page->mapping = NULL; |
1eb5ac64 NP |
1736 | if (current->reclaim_state) |
1737 | current->reclaim_state->reclaimed_slab += pages; | |
27ee57c9 VD |
1738 | memcg_uncharge_slab(page, order, s); |
1739 | __free_pages(page, order); | |
81819f0f CL |
1740 | } |
1741 | ||
1742 | static void rcu_free_slab(struct rcu_head *h) | |
1743 | { | |
bf68c214 | 1744 | struct page *page = container_of(h, struct page, rcu_head); |
da9a638c | 1745 | |
1b4f59e3 | 1746 | __free_slab(page->slab_cache, page); |
81819f0f CL |
1747 | } |
1748 | ||
1749 | static void free_slab(struct kmem_cache *s, struct page *page) | |
1750 | { | |
5f0d5a3a | 1751 | if (unlikely(s->flags & SLAB_TYPESAFE_BY_RCU)) { |
bf68c214 | 1752 | call_rcu(&page->rcu_head, rcu_free_slab); |
81819f0f CL |
1753 | } else |
1754 | __free_slab(s, page); | |
1755 | } | |
1756 | ||
1757 | static void discard_slab(struct kmem_cache *s, struct page *page) | |
1758 | { | |
205ab99d | 1759 | dec_slabs_node(s, page_to_nid(page), page->objects); |
81819f0f CL |
1760 | free_slab(s, page); |
1761 | } | |
1762 | ||
1763 | /* | |
5cc6eee8 | 1764 | * Management of partially allocated slabs. |
81819f0f | 1765 | */ |
1e4dd946 SR |
1766 | static inline void |
1767 | __add_partial(struct kmem_cache_node *n, struct page *page, int tail) | |
81819f0f | 1768 | { |
e95eed57 | 1769 | n->nr_partial++; |
136333d1 | 1770 | if (tail == DEACTIVATE_TO_TAIL) |
7c2e132c CL |
1771 | list_add_tail(&page->lru, &n->partial); |
1772 | else | |
1773 | list_add(&page->lru, &n->partial); | |
81819f0f CL |
1774 | } |
1775 | ||
1e4dd946 SR |
1776 | static inline void add_partial(struct kmem_cache_node *n, |
1777 | struct page *page, int tail) | |
62e346a8 | 1778 | { |
c65c1877 | 1779 | lockdep_assert_held(&n->list_lock); |
1e4dd946 SR |
1780 | __add_partial(n, page, tail); |
1781 | } | |
c65c1877 | 1782 | |
1e4dd946 SR |
1783 | static inline void remove_partial(struct kmem_cache_node *n, |
1784 | struct page *page) | |
1785 | { | |
1786 | lockdep_assert_held(&n->list_lock); | |
52b4b950 DS |
1787 | list_del(&page->lru); |
1788 | n->nr_partial--; | |
1e4dd946 SR |
1789 | } |
1790 | ||
81819f0f | 1791 | /* |
7ced3719 CL |
1792 | * Remove slab from the partial list, freeze it and |
1793 | * return the pointer to the freelist. | |
81819f0f | 1794 | * |
497b66f2 | 1795 | * Returns a list of objects or NULL if it fails. |
81819f0f | 1796 | */ |
497b66f2 | 1797 | static inline void *acquire_slab(struct kmem_cache *s, |
acd19fd1 | 1798 | struct kmem_cache_node *n, struct page *page, |
633b0764 | 1799 | int mode, int *objects) |
81819f0f | 1800 | { |
2cfb7455 CL |
1801 | void *freelist; |
1802 | unsigned long counters; | |
1803 | struct page new; | |
1804 | ||
c65c1877 PZ |
1805 | lockdep_assert_held(&n->list_lock); |
1806 | ||
2cfb7455 CL |
1807 | /* |
1808 | * Zap the freelist and set the frozen bit. | |
1809 | * The old freelist is the list of objects for the | |
1810 | * per cpu allocation list. | |
1811 | */ | |
7ced3719 CL |
1812 | freelist = page->freelist; |
1813 | counters = page->counters; | |
1814 | new.counters = counters; | |
633b0764 | 1815 | *objects = new.objects - new.inuse; |
23910c50 | 1816 | if (mode) { |
7ced3719 | 1817 | new.inuse = page->objects; |
23910c50 PE |
1818 | new.freelist = NULL; |
1819 | } else { | |
1820 | new.freelist = freelist; | |
1821 | } | |
2cfb7455 | 1822 | |
a0132ac0 | 1823 | VM_BUG_ON(new.frozen); |
7ced3719 | 1824 | new.frozen = 1; |
2cfb7455 | 1825 | |
7ced3719 | 1826 | if (!__cmpxchg_double_slab(s, page, |
2cfb7455 | 1827 | freelist, counters, |
02d7633f | 1828 | new.freelist, new.counters, |
7ced3719 | 1829 | "acquire_slab")) |
7ced3719 | 1830 | return NULL; |
2cfb7455 CL |
1831 | |
1832 | remove_partial(n, page); | |
7ced3719 | 1833 | WARN_ON(!freelist); |
49e22585 | 1834 | return freelist; |
81819f0f CL |
1835 | } |
1836 | ||
633b0764 | 1837 | static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain); |
8ba00bb6 | 1838 | static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags); |
49e22585 | 1839 | |
81819f0f | 1840 | /* |
672bba3a | 1841 | * Try to allocate a partial slab from a specific node. |
81819f0f | 1842 | */ |
8ba00bb6 JK |
1843 | static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, |
1844 | struct kmem_cache_cpu *c, gfp_t flags) | |
81819f0f | 1845 | { |
49e22585 CL |
1846 | struct page *page, *page2; |
1847 | void *object = NULL; | |
e5d9998f | 1848 | unsigned int available = 0; |
633b0764 | 1849 | int objects; |
81819f0f CL |
1850 | |
1851 | /* | |
1852 | * Racy check. If we mistakenly see no partial slabs then we | |
1853 | * just allocate an empty slab. If we mistakenly try to get a | |
672bba3a CL |
1854 | * partial slab and there is none available then get_partials() |
1855 | * will return NULL. | |
81819f0f CL |
1856 | */ |
1857 | if (!n || !n->nr_partial) | |
1858 | return NULL; | |
1859 | ||
1860 | spin_lock(&n->list_lock); | |
49e22585 | 1861 | list_for_each_entry_safe(page, page2, &n->partial, lru) { |
8ba00bb6 | 1862 | void *t; |
49e22585 | 1863 | |
8ba00bb6 JK |
1864 | if (!pfmemalloc_match(page, flags)) |
1865 | continue; | |
1866 | ||
633b0764 | 1867 | t = acquire_slab(s, n, page, object == NULL, &objects); |
49e22585 CL |
1868 | if (!t) |
1869 | break; | |
1870 | ||
633b0764 | 1871 | available += objects; |
12d79634 | 1872 | if (!object) { |
49e22585 | 1873 | c->page = page; |
49e22585 | 1874 | stat(s, ALLOC_FROM_PARTIAL); |
49e22585 | 1875 | object = t; |
49e22585 | 1876 | } else { |
633b0764 | 1877 | put_cpu_partial(s, page, 0); |
8028dcea | 1878 | stat(s, CPU_PARTIAL_NODE); |
49e22585 | 1879 | } |
345c905d | 1880 | if (!kmem_cache_has_cpu_partial(s) |
e6d0e1dc | 1881 | || available > slub_cpu_partial(s) / 2) |
49e22585 CL |
1882 | break; |
1883 | ||
497b66f2 | 1884 | } |
81819f0f | 1885 | spin_unlock(&n->list_lock); |
497b66f2 | 1886 | return object; |
81819f0f CL |
1887 | } |
1888 | ||
1889 | /* | |
672bba3a | 1890 | * Get a page from somewhere. Search in increasing NUMA distances. |
81819f0f | 1891 | */ |
de3ec035 | 1892 | static void *get_any_partial(struct kmem_cache *s, gfp_t flags, |
acd19fd1 | 1893 | struct kmem_cache_cpu *c) |
81819f0f CL |
1894 | { |
1895 | #ifdef CONFIG_NUMA | |
1896 | struct zonelist *zonelist; | |
dd1a239f | 1897 | struct zoneref *z; |
54a6eb5c MG |
1898 | struct zone *zone; |
1899 | enum zone_type high_zoneidx = gfp_zone(flags); | |
497b66f2 | 1900 | void *object; |
cc9a6c87 | 1901 | unsigned int cpuset_mems_cookie; |
81819f0f CL |
1902 | |
1903 | /* | |
672bba3a CL |
1904 | * The defrag ratio allows a configuration of the tradeoffs between |
1905 | * inter node defragmentation and node local allocations. A lower | |
1906 | * defrag_ratio increases the tendency to do local allocations | |
1907 | * instead of attempting to obtain partial slabs from other nodes. | |
81819f0f | 1908 | * |
672bba3a CL |
1909 | * If the defrag_ratio is set to 0 then kmalloc() always |
1910 | * returns node local objects. If the ratio is higher then kmalloc() | |
1911 | * may return off node objects because partial slabs are obtained | |
1912 | * from other nodes and filled up. | |
81819f0f | 1913 | * |
43efd3ea LP |
1914 | * If /sys/kernel/slab/xx/remote_node_defrag_ratio is set to 100 |
1915 | * (which makes defrag_ratio = 1000) then every (well almost) | |
1916 | * allocation will first attempt to defrag slab caches on other nodes. | |
1917 | * This means scanning over all nodes to look for partial slabs which | |
1918 | * may be expensive if we do it every time we are trying to find a slab | |
672bba3a | 1919 | * with available objects. |
81819f0f | 1920 | */ |
9824601e CL |
1921 | if (!s->remote_node_defrag_ratio || |
1922 | get_cycles() % 1024 > s->remote_node_defrag_ratio) | |
81819f0f CL |
1923 | return NULL; |
1924 | ||
cc9a6c87 | 1925 | do { |
d26914d1 | 1926 | cpuset_mems_cookie = read_mems_allowed_begin(); |
2a389610 | 1927 | zonelist = node_zonelist(mempolicy_slab_node(), flags); |
cc9a6c87 MG |
1928 | for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { |
1929 | struct kmem_cache_node *n; | |
1930 | ||
1931 | n = get_node(s, zone_to_nid(zone)); | |
1932 | ||
dee2f8aa | 1933 | if (n && cpuset_zone_allowed(zone, flags) && |
cc9a6c87 | 1934 | n->nr_partial > s->min_partial) { |
8ba00bb6 | 1935 | object = get_partial_node(s, n, c, flags); |
cc9a6c87 MG |
1936 | if (object) { |
1937 | /* | |
d26914d1 MG |
1938 | * Don't check read_mems_allowed_retry() |
1939 | * here - if mems_allowed was updated in | |
1940 | * parallel, that was a harmless race | |
1941 | * between allocation and the cpuset | |
1942 | * update | |
cc9a6c87 | 1943 | */ |
cc9a6c87 MG |
1944 | return object; |
1945 | } | |
c0ff7453 | 1946 | } |
81819f0f | 1947 | } |
d26914d1 | 1948 | } while (read_mems_allowed_retry(cpuset_mems_cookie)); |
81819f0f CL |
1949 | #endif |
1950 | return NULL; | |
1951 | } | |
1952 | ||
1953 | /* | |
1954 | * Get a partial page, lock it and return it. | |
1955 | */ | |
497b66f2 | 1956 | static void *get_partial(struct kmem_cache *s, gfp_t flags, int node, |
acd19fd1 | 1957 | struct kmem_cache_cpu *c) |
81819f0f | 1958 | { |
497b66f2 | 1959 | void *object; |
a561ce00 JK |
1960 | int searchnode = node; |
1961 | ||
1962 | if (node == NUMA_NO_NODE) | |
1963 | searchnode = numa_mem_id(); | |
1964 | else if (!node_present_pages(node)) | |
1965 | searchnode = node_to_mem_node(node); | |
81819f0f | 1966 | |
8ba00bb6 | 1967 | object = get_partial_node(s, get_node(s, searchnode), c, flags); |
497b66f2 CL |
1968 | if (object || node != NUMA_NO_NODE) |
1969 | return object; | |
81819f0f | 1970 | |
acd19fd1 | 1971 | return get_any_partial(s, flags, c); |
81819f0f CL |
1972 | } |
1973 | ||
8a5ec0ba CL |
1974 | #ifdef CONFIG_PREEMPT |
1975 | /* | |
1976 | * Calculate the next globally unique transaction for disambiguiation | |
1977 | * during cmpxchg. The transactions start with the cpu number and are then | |
1978 | * incremented by CONFIG_NR_CPUS. | |
1979 | */ | |
1980 | #define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS) | |
1981 | #else | |
1982 | /* | |
1983 | * No preemption supported therefore also no need to check for | |
1984 | * different cpus. | |
1985 | */ | |
1986 | #define TID_STEP 1 | |
1987 | #endif | |
1988 | ||
1989 | static inline unsigned long next_tid(unsigned long tid) | |
1990 | { | |
1991 | return tid + TID_STEP; | |
1992 | } | |
1993 | ||
1994 | static inline unsigned int tid_to_cpu(unsigned long tid) | |
1995 | { | |
1996 | return tid % TID_STEP; | |
1997 | } | |
1998 | ||
1999 | static inline unsigned long tid_to_event(unsigned long tid) | |
2000 | { | |
2001 | return tid / TID_STEP; | |
2002 | } | |
2003 | ||
2004 | static inline unsigned int init_tid(int cpu) | |
2005 | { | |
2006 | return cpu; | |
2007 | } | |
2008 | ||
2009 | static inline void note_cmpxchg_failure(const char *n, | |
2010 | const struct kmem_cache *s, unsigned long tid) | |
2011 | { | |
2012 | #ifdef SLUB_DEBUG_CMPXCHG | |
2013 | unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid); | |
2014 | ||
f9f58285 | 2015 | pr_info("%s %s: cmpxchg redo ", n, s->name); |
8a5ec0ba CL |
2016 | |
2017 | #ifdef CONFIG_PREEMPT | |
2018 | if (tid_to_cpu(tid) != tid_to_cpu(actual_tid)) | |
f9f58285 | 2019 | pr_warn("due to cpu change %d -> %d\n", |
8a5ec0ba CL |
2020 | tid_to_cpu(tid), tid_to_cpu(actual_tid)); |
2021 | else | |
2022 | #endif | |
2023 | if (tid_to_event(tid) != tid_to_event(actual_tid)) | |
f9f58285 | 2024 | pr_warn("due to cpu running other code. Event %ld->%ld\n", |
8a5ec0ba CL |
2025 | tid_to_event(tid), tid_to_event(actual_tid)); |
2026 | else | |
f9f58285 | 2027 | pr_warn("for unknown reason: actual=%lx was=%lx target=%lx\n", |
8a5ec0ba CL |
2028 | actual_tid, tid, next_tid(tid)); |
2029 | #endif | |
4fdccdfb | 2030 | stat(s, CMPXCHG_DOUBLE_CPU_FAIL); |
8a5ec0ba CL |
2031 | } |
2032 | ||
788e1aad | 2033 | static void init_kmem_cache_cpus(struct kmem_cache *s) |
8a5ec0ba | 2034 | { |
8a5ec0ba CL |
2035 | int cpu; |
2036 | ||
2037 | for_each_possible_cpu(cpu) | |
2038 | per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu); | |
8a5ec0ba | 2039 | } |
2cfb7455 | 2040 | |
81819f0f CL |
2041 | /* |
2042 | * Remove the cpu slab | |
2043 | */ | |
d0e0ac97 | 2044 | static void deactivate_slab(struct kmem_cache *s, struct page *page, |
d4ff6d35 | 2045 | void *freelist, struct kmem_cache_cpu *c) |
81819f0f | 2046 | { |
2cfb7455 | 2047 | enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE }; |
2cfb7455 CL |
2048 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
2049 | int lock = 0; | |
2050 | enum slab_modes l = M_NONE, m = M_NONE; | |
2cfb7455 | 2051 | void *nextfree; |
136333d1 | 2052 | int tail = DEACTIVATE_TO_HEAD; |
2cfb7455 CL |
2053 | struct page new; |
2054 | struct page old; | |
2055 | ||
2056 | if (page->freelist) { | |
84e554e6 | 2057 | stat(s, DEACTIVATE_REMOTE_FREES); |
136333d1 | 2058 | tail = DEACTIVATE_TO_TAIL; |
2cfb7455 CL |
2059 | } |
2060 | ||
894b8788 | 2061 | /* |
2cfb7455 CL |
2062 | * Stage one: Free all available per cpu objects back |
2063 | * to the page freelist while it is still frozen. Leave the | |
2064 | * last one. | |
2065 | * | |
2066 | * There is no need to take the list->lock because the page | |
2067 | * is still frozen. | |
2068 | */ | |
2069 | while (freelist && (nextfree = get_freepointer(s, freelist))) { | |
2070 | void *prior; | |
2071 | unsigned long counters; | |
2072 | ||
2073 | do { | |
2074 | prior = page->freelist; | |
2075 | counters = page->counters; | |
2076 | set_freepointer(s, freelist, prior); | |
2077 | new.counters = counters; | |
2078 | new.inuse--; | |
a0132ac0 | 2079 | VM_BUG_ON(!new.frozen); |
2cfb7455 | 2080 | |
1d07171c | 2081 | } while (!__cmpxchg_double_slab(s, page, |
2cfb7455 CL |
2082 | prior, counters, |
2083 | freelist, new.counters, | |
2084 | "drain percpu freelist")); | |
2085 | ||
2086 | freelist = nextfree; | |
2087 | } | |
2088 | ||
894b8788 | 2089 | /* |
2cfb7455 CL |
2090 | * Stage two: Ensure that the page is unfrozen while the |
2091 | * list presence reflects the actual number of objects | |
2092 | * during unfreeze. | |
2093 | * | |
2094 | * We setup the list membership and then perform a cmpxchg | |
2095 | * with the count. If there is a mismatch then the page | |
2096 | * is not unfrozen but the page is on the wrong list. | |
2097 | * | |
2098 | * Then we restart the process which may have to remove | |
2099 | * the page from the list that we just put it on again | |
2100 | * because the number of objects in the slab may have | |
2101 | * changed. | |
894b8788 | 2102 | */ |
2cfb7455 | 2103 | redo: |
894b8788 | 2104 | |
2cfb7455 CL |
2105 | old.freelist = page->freelist; |
2106 | old.counters = page->counters; | |
a0132ac0 | 2107 | VM_BUG_ON(!old.frozen); |
7c2e132c | 2108 | |
2cfb7455 CL |
2109 | /* Determine target state of the slab */ |
2110 | new.counters = old.counters; | |
2111 | if (freelist) { | |
2112 | new.inuse--; | |
2113 | set_freepointer(s, freelist, old.freelist); | |
2114 | new.freelist = freelist; | |
2115 | } else | |
2116 | new.freelist = old.freelist; | |
2117 | ||
2118 | new.frozen = 0; | |
2119 | ||
8a5b20ae | 2120 | if (!new.inuse && n->nr_partial >= s->min_partial) |
2cfb7455 CL |
2121 | m = M_FREE; |
2122 | else if (new.freelist) { | |
2123 | m = M_PARTIAL; | |
2124 | if (!lock) { | |
2125 | lock = 1; | |
2126 | /* | |
2127 | * Taking the spinlock removes the possiblity | |
2128 | * that acquire_slab() will see a slab page that | |
2129 | * is frozen | |
2130 | */ | |
2131 | spin_lock(&n->list_lock); | |
2132 | } | |
2133 | } else { | |
2134 | m = M_FULL; | |
2135 | if (kmem_cache_debug(s) && !lock) { | |
2136 | lock = 1; | |
2137 | /* | |
2138 | * This also ensures that the scanning of full | |
2139 | * slabs from diagnostic functions will not see | |
2140 | * any frozen slabs. | |
2141 | */ | |
2142 | spin_lock(&n->list_lock); | |
2143 | } | |
2144 | } | |
2145 | ||
2146 | if (l != m) { | |
2cfb7455 | 2147 | if (l == M_PARTIAL) |
2cfb7455 | 2148 | remove_partial(n, page); |
2cfb7455 | 2149 | else if (l == M_FULL) |
c65c1877 | 2150 | remove_full(s, n, page); |
2cfb7455 | 2151 | |
88349a28 | 2152 | if (m == M_PARTIAL) |
2cfb7455 | 2153 | add_partial(n, page, tail); |
88349a28 | 2154 | else if (m == M_FULL) |
2cfb7455 | 2155 | add_full(s, n, page); |
2cfb7455 CL |
2156 | } |
2157 | ||
2158 | l = m; | |
1d07171c | 2159 | if (!__cmpxchg_double_slab(s, page, |
2cfb7455 CL |
2160 | old.freelist, old.counters, |
2161 | new.freelist, new.counters, | |
2162 | "unfreezing slab")) | |
2163 | goto redo; | |
2164 | ||
2cfb7455 CL |
2165 | if (lock) |
2166 | spin_unlock(&n->list_lock); | |
2167 | ||
88349a28 WY |
2168 | if (m == M_PARTIAL) |
2169 | stat(s, tail); | |
2170 | else if (m == M_FULL) | |
2171 | stat(s, DEACTIVATE_FULL); | |
2172 | else if (m == M_FREE) { | |
2cfb7455 CL |
2173 | stat(s, DEACTIVATE_EMPTY); |
2174 | discard_slab(s, page); | |
2175 | stat(s, FREE_SLAB); | |
894b8788 | 2176 | } |
d4ff6d35 WY |
2177 | |
2178 | c->page = NULL; | |
2179 | c->freelist = NULL; | |
81819f0f CL |
2180 | } |
2181 | ||
d24ac77f JK |
2182 | /* |
2183 | * Unfreeze all the cpu partial slabs. | |
2184 | * | |
59a09917 CL |
2185 | * This function must be called with interrupts disabled |
2186 | * for the cpu using c (or some other guarantee must be there | |
2187 | * to guarantee no concurrent accesses). | |
d24ac77f | 2188 | */ |
59a09917 CL |
2189 | static void unfreeze_partials(struct kmem_cache *s, |
2190 | struct kmem_cache_cpu *c) | |
49e22585 | 2191 | { |
345c905d | 2192 | #ifdef CONFIG_SLUB_CPU_PARTIAL |
43d77867 | 2193 | struct kmem_cache_node *n = NULL, *n2 = NULL; |
9ada1934 | 2194 | struct page *page, *discard_page = NULL; |
49e22585 CL |
2195 | |
2196 | while ((page = c->partial)) { | |
49e22585 CL |
2197 | struct page new; |
2198 | struct page old; | |
2199 | ||
2200 | c->partial = page->next; | |
43d77867 JK |
2201 | |
2202 | n2 = get_node(s, page_to_nid(page)); | |
2203 | if (n != n2) { | |
2204 | if (n) | |
2205 | spin_unlock(&n->list_lock); | |
2206 | ||
2207 | n = n2; | |
2208 | spin_lock(&n->list_lock); | |
2209 | } | |
49e22585 CL |
2210 | |
2211 | do { | |
2212 | ||
2213 | old.freelist = page->freelist; | |
2214 | old.counters = page->counters; | |
a0132ac0 | 2215 | VM_BUG_ON(!old.frozen); |
49e22585 CL |
2216 | |
2217 | new.counters = old.counters; | |
2218 | new.freelist = old.freelist; | |
2219 | ||
2220 | new.frozen = 0; | |
2221 | ||
d24ac77f | 2222 | } while (!__cmpxchg_double_slab(s, page, |
49e22585 CL |
2223 | old.freelist, old.counters, |
2224 | new.freelist, new.counters, | |
2225 | "unfreezing slab")); | |
2226 | ||
8a5b20ae | 2227 | if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) { |
9ada1934 SL |
2228 | page->next = discard_page; |
2229 | discard_page = page; | |
43d77867 JK |
2230 | } else { |
2231 | add_partial(n, page, DEACTIVATE_TO_TAIL); | |
2232 | stat(s, FREE_ADD_PARTIAL); | |
49e22585 CL |
2233 | } |
2234 | } | |
2235 | ||
2236 | if (n) | |
2237 | spin_unlock(&n->list_lock); | |
9ada1934 SL |
2238 | |
2239 | while (discard_page) { | |
2240 | page = discard_page; | |
2241 | discard_page = discard_page->next; | |
2242 | ||
2243 | stat(s, DEACTIVATE_EMPTY); | |
2244 | discard_slab(s, page); | |
2245 | stat(s, FREE_SLAB); | |
2246 | } | |
345c905d | 2247 | #endif |
49e22585 CL |
2248 | } |
2249 | ||
2250 | /* | |
2251 | * Put a page that was just frozen (in __slab_free) into a partial page | |
0d2d5d40 | 2252 | * slot if available. |
49e22585 CL |
2253 | * |
2254 | * If we did not find a slot then simply move all the partials to the | |
2255 | * per node partial list. | |
2256 | */ | |
633b0764 | 2257 | static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) |
49e22585 | 2258 | { |
345c905d | 2259 | #ifdef CONFIG_SLUB_CPU_PARTIAL |
49e22585 CL |
2260 | struct page *oldpage; |
2261 | int pages; | |
2262 | int pobjects; | |
2263 | ||
d6e0b7fa | 2264 | preempt_disable(); |
49e22585 CL |
2265 | do { |
2266 | pages = 0; | |
2267 | pobjects = 0; | |
2268 | oldpage = this_cpu_read(s->cpu_slab->partial); | |
2269 | ||
2270 | if (oldpage) { | |
2271 | pobjects = oldpage->pobjects; | |
2272 | pages = oldpage->pages; | |
2273 | if (drain && pobjects > s->cpu_partial) { | |
2274 | unsigned long flags; | |
2275 | /* | |
2276 | * partial array is full. Move the existing | |
2277 | * set to the per node partial list. | |
2278 | */ | |
2279 | local_irq_save(flags); | |
59a09917 | 2280 | unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); |
49e22585 | 2281 | local_irq_restore(flags); |
e24fc410 | 2282 | oldpage = NULL; |
49e22585 CL |
2283 | pobjects = 0; |
2284 | pages = 0; | |
8028dcea | 2285 | stat(s, CPU_PARTIAL_DRAIN); |
49e22585 CL |
2286 | } |
2287 | } | |
2288 | ||
2289 | pages++; | |
2290 | pobjects += page->objects - page->inuse; | |
2291 | ||
2292 | page->pages = pages; | |
2293 | page->pobjects = pobjects; | |
2294 | page->next = oldpage; | |
2295 | ||
d0e0ac97 CG |
2296 | } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) |
2297 | != oldpage); | |
d6e0b7fa VD |
2298 | if (unlikely(!s->cpu_partial)) { |
2299 | unsigned long flags; | |
2300 | ||
2301 | local_irq_save(flags); | |
2302 | unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); | |
2303 | local_irq_restore(flags); | |
2304 | } | |
2305 | preempt_enable(); | |
345c905d | 2306 | #endif |
49e22585 CL |
2307 | } |
2308 | ||
dfb4f096 | 2309 | static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) |
81819f0f | 2310 | { |
84e554e6 | 2311 | stat(s, CPUSLAB_FLUSH); |
d4ff6d35 | 2312 | deactivate_slab(s, c->page, c->freelist, c); |
c17dda40 CL |
2313 | |
2314 | c->tid = next_tid(c->tid); | |
81819f0f CL |
2315 | } |
2316 | ||
2317 | /* | |
2318 | * Flush cpu slab. | |
6446faa2 | 2319 | * |
81819f0f CL |
2320 | * Called from IPI handler with interrupts disabled. |
2321 | */ | |
0c710013 | 2322 | static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) |
81819f0f | 2323 | { |
9dfc6e68 | 2324 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); |
81819f0f | 2325 | |
1265ef2d WY |
2326 | if (c->page) |
2327 | flush_slab(s, c); | |
49e22585 | 2328 | |
1265ef2d | 2329 | unfreeze_partials(s, c); |
81819f0f CL |
2330 | } |
2331 | ||
2332 | static void flush_cpu_slab(void *d) | |
2333 | { | |
2334 | struct kmem_cache *s = d; | |
81819f0f | 2335 | |
dfb4f096 | 2336 | __flush_cpu_slab(s, smp_processor_id()); |
81819f0f CL |
2337 | } |
2338 | ||
a8364d55 GBY |
2339 | static bool has_cpu_slab(int cpu, void *info) |
2340 | { | |
2341 | struct kmem_cache *s = info; | |
2342 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); | |
2343 | ||
a93cf07b | 2344 | return c->page || slub_percpu_partial(c); |
a8364d55 GBY |
2345 | } |
2346 | ||
81819f0f CL |
2347 | static void flush_all(struct kmem_cache *s) |
2348 | { | |
a8364d55 | 2349 | on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC); |
81819f0f CL |
2350 | } |
2351 | ||
a96a87bf SAS |
2352 | /* |
2353 | * Use the cpu notifier to insure that the cpu slabs are flushed when | |
2354 | * necessary. | |
2355 | */ | |
2356 | static int slub_cpu_dead(unsigned int cpu) | |
2357 | { | |
2358 | struct kmem_cache *s; | |
2359 | unsigned long flags; | |
2360 | ||
2361 | mutex_lock(&slab_mutex); | |
2362 | list_for_each_entry(s, &slab_caches, list) { | |
2363 | local_irq_save(flags); | |
2364 | __flush_cpu_slab(s, cpu); | |
2365 | local_irq_restore(flags); | |
2366 | } | |
2367 | mutex_unlock(&slab_mutex); | |
2368 | return 0; | |
2369 | } | |
2370 | ||
dfb4f096 CL |
2371 | /* |
2372 | * Check if the objects in a per cpu structure fit numa | |
2373 | * locality expectations. | |
2374 | */ | |
57d437d2 | 2375 | static inline int node_match(struct page *page, int node) |
dfb4f096 CL |
2376 | { |
2377 | #ifdef CONFIG_NUMA | |
6159d0f5 | 2378 | if (node != NUMA_NO_NODE && page_to_nid(page) != node) |
dfb4f096 CL |
2379 | return 0; |
2380 | #endif | |
2381 | return 1; | |
2382 | } | |
2383 | ||
9a02d699 | 2384 | #ifdef CONFIG_SLUB_DEBUG |
781b2ba6 PE |
2385 | static int count_free(struct page *page) |
2386 | { | |
2387 | return page->objects - page->inuse; | |
2388 | } | |
2389 | ||
9a02d699 DR |
2390 | static inline unsigned long node_nr_objs(struct kmem_cache_node *n) |
2391 | { | |
2392 | return atomic_long_read(&n->total_objects); | |
2393 | } | |
2394 | #endif /* CONFIG_SLUB_DEBUG */ | |
2395 | ||
2396 | #if defined(CONFIG_SLUB_DEBUG) || defined(CONFIG_SYSFS) | |
781b2ba6 PE |
2397 | static unsigned long count_partial(struct kmem_cache_node *n, |
2398 | int (*get_count)(struct page *)) | |
2399 | { | |
2400 | unsigned long flags; | |
2401 | unsigned long x = 0; | |
2402 | struct page *page; | |
2403 | ||
2404 | spin_lock_irqsave(&n->list_lock, flags); | |
2405 | list_for_each_entry(page, &n->partial, lru) | |
2406 | x += get_count(page); | |
2407 | spin_unlock_irqrestore(&n->list_lock, flags); | |
2408 | return x; | |
2409 | } | |
9a02d699 | 2410 | #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */ |
26c02cf0 | 2411 | |
781b2ba6 PE |
2412 | static noinline void |
2413 | slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid) | |
2414 | { | |
9a02d699 DR |
2415 | #ifdef CONFIG_SLUB_DEBUG |
2416 | static DEFINE_RATELIMIT_STATE(slub_oom_rs, DEFAULT_RATELIMIT_INTERVAL, | |
2417 | DEFAULT_RATELIMIT_BURST); | |
781b2ba6 | 2418 | int node; |
fa45dc25 | 2419 | struct kmem_cache_node *n; |
781b2ba6 | 2420 | |
9a02d699 DR |
2421 | if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) |
2422 | return; | |
2423 | ||
5b3810e5 VB |
2424 | pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n", |
2425 | nid, gfpflags, &gfpflags); | |
19af27af | 2426 | pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u, min order: %u\n", |
f9f58285 FF |
2427 | s->name, s->object_size, s->size, oo_order(s->oo), |
2428 | oo_order(s->min)); | |
781b2ba6 | 2429 | |
3b0efdfa | 2430 | if (oo_order(s->min) > get_order(s->object_size)) |
f9f58285 FF |
2431 | pr_warn(" %s debugging increased min order, use slub_debug=O to disable.\n", |
2432 | s->name); | |
fa5ec8a1 | 2433 | |
fa45dc25 | 2434 | for_each_kmem_cache_node(s, node, n) { |
781b2ba6 PE |
2435 | unsigned long nr_slabs; |
2436 | unsigned long nr_objs; | |
2437 | unsigned long nr_free; | |
2438 | ||
26c02cf0 AB |
2439 | nr_free = count_partial(n, count_free); |
2440 | nr_slabs = node_nr_slabs(n); | |
2441 | nr_objs = node_nr_objs(n); | |
781b2ba6 | 2442 | |
f9f58285 | 2443 | pr_warn(" node %d: slabs: %ld, objs: %ld, free: %ld\n", |
781b2ba6 PE |
2444 | node, nr_slabs, nr_objs, nr_free); |
2445 | } | |
9a02d699 | 2446 | #endif |
781b2ba6 PE |
2447 | } |
2448 | ||
497b66f2 CL |
2449 | static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags, |
2450 | int node, struct kmem_cache_cpu **pc) | |
2451 | { | |
6faa6833 | 2452 | void *freelist; |
188fd063 CL |
2453 | struct kmem_cache_cpu *c = *pc; |
2454 | struct page *page; | |
497b66f2 | 2455 | |
128227e7 MW |
2456 | WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO)); |
2457 | ||
188fd063 | 2458 | freelist = get_partial(s, flags, node, c); |
497b66f2 | 2459 | |
188fd063 CL |
2460 | if (freelist) |
2461 | return freelist; | |
2462 | ||
2463 | page = new_slab(s, flags, node); | |
497b66f2 | 2464 | if (page) { |
7c8e0181 | 2465 | c = raw_cpu_ptr(s->cpu_slab); |
497b66f2 CL |
2466 | if (c->page) |
2467 | flush_slab(s, c); | |
2468 | ||
2469 | /* | |
2470 | * No other reference to the page yet so we can | |
2471 | * muck around with it freely without cmpxchg | |
2472 | */ | |
6faa6833 | 2473 | freelist = page->freelist; |
497b66f2 CL |
2474 | page->freelist = NULL; |
2475 | ||
2476 | stat(s, ALLOC_SLAB); | |
497b66f2 CL |
2477 | c->page = page; |
2478 | *pc = c; | |
2479 | } else | |
6faa6833 | 2480 | freelist = NULL; |
497b66f2 | 2481 | |
6faa6833 | 2482 | return freelist; |
497b66f2 CL |
2483 | } |
2484 | ||
072bb0aa MG |
2485 | static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags) |
2486 | { | |
2487 | if (unlikely(PageSlabPfmemalloc(page))) | |
2488 | return gfp_pfmemalloc_allowed(gfpflags); | |
2489 | ||
2490 | return true; | |
2491 | } | |
2492 | ||
213eeb9f | 2493 | /* |
d0e0ac97 CG |
2494 | * Check the page->freelist of a page and either transfer the freelist to the |
2495 | * per cpu freelist or deactivate the page. | |
213eeb9f CL |
2496 | * |
2497 | * The page is still frozen if the return value is not NULL. | |
2498 | * | |
2499 | * If this function returns NULL then the page has been unfrozen. | |
d24ac77f JK |
2500 | * |
2501 | * This function must be called with interrupt disabled. | |
213eeb9f CL |
2502 | */ |
2503 | static inline void *get_freelist(struct kmem_cache *s, struct page *page) | |
2504 | { | |
2505 | struct page new; | |
2506 | unsigned long counters; | |
2507 | void *freelist; | |
2508 | ||
2509 | do { | |
2510 | freelist = page->freelist; | |
2511 | counters = page->counters; | |
6faa6833 | 2512 | |
213eeb9f | 2513 | new.counters = counters; |
a0132ac0 | 2514 | VM_BUG_ON(!new.frozen); |
213eeb9f CL |
2515 | |
2516 | new.inuse = page->objects; | |
2517 | new.frozen = freelist != NULL; | |
2518 | ||
d24ac77f | 2519 | } while (!__cmpxchg_double_slab(s, page, |
213eeb9f CL |
2520 | freelist, counters, |
2521 | NULL, new.counters, | |
2522 | "get_freelist")); | |
2523 | ||
2524 | return freelist; | |
2525 | } | |
2526 | ||
81819f0f | 2527 | /* |
894b8788 CL |
2528 | * Slow path. The lockless freelist is empty or we need to perform |
2529 | * debugging duties. | |
2530 | * | |
894b8788 CL |
2531 | * Processing is still very fast if new objects have been freed to the |
2532 | * regular freelist. In that case we simply take over the regular freelist | |
2533 | * as the lockless freelist and zap the regular freelist. | |
81819f0f | 2534 | * |
894b8788 CL |
2535 | * If that is not working then we fall back to the partial lists. We take the |
2536 | * first element of the freelist as the object to allocate now and move the | |
2537 | * rest of the freelist to the lockless freelist. | |
81819f0f | 2538 | * |
894b8788 | 2539 | * And if we were unable to get a new slab from the partial slab lists then |
6446faa2 CL |
2540 | * we need to allocate a new slab. This is the slowest path since it involves |
2541 | * a call to the page allocator and the setup of a new slab. | |
a380a3c7 CL |
2542 | * |
2543 | * Version of __slab_alloc to use when we know that interrupts are | |
2544 | * already disabled (which is the case for bulk allocation). | |
81819f0f | 2545 | */ |
a380a3c7 | 2546 | static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, |
ce71e27c | 2547 | unsigned long addr, struct kmem_cache_cpu *c) |
81819f0f | 2548 | { |
6faa6833 | 2549 | void *freelist; |
f6e7def7 | 2550 | struct page *page; |
81819f0f | 2551 | |
f6e7def7 CL |
2552 | page = c->page; |
2553 | if (!page) | |
81819f0f | 2554 | goto new_slab; |
49e22585 | 2555 | redo: |
6faa6833 | 2556 | |
57d437d2 | 2557 | if (unlikely(!node_match(page, node))) { |
a561ce00 JK |
2558 | int searchnode = node; |
2559 | ||
2560 | if (node != NUMA_NO_NODE && !node_present_pages(node)) | |
2561 | searchnode = node_to_mem_node(node); | |
2562 | ||
2563 | if (unlikely(!node_match(page, searchnode))) { | |
2564 | stat(s, ALLOC_NODE_MISMATCH); | |
d4ff6d35 | 2565 | deactivate_slab(s, page, c->freelist, c); |
a561ce00 JK |
2566 | goto new_slab; |
2567 | } | |
fc59c053 | 2568 | } |
6446faa2 | 2569 | |
072bb0aa MG |
2570 | /* |
2571 | * By rights, we should be searching for a slab page that was | |
2572 | * PFMEMALLOC but right now, we are losing the pfmemalloc | |
2573 | * information when the page leaves the per-cpu allocator | |
2574 | */ | |
2575 | if (unlikely(!pfmemalloc_match(page, gfpflags))) { | |
d4ff6d35 | 2576 | deactivate_slab(s, page, c->freelist, c); |
072bb0aa MG |
2577 | goto new_slab; |
2578 | } | |
2579 | ||
73736e03 | 2580 | /* must check again c->freelist in case of cpu migration or IRQ */ |
6faa6833 CL |
2581 | freelist = c->freelist; |
2582 | if (freelist) | |
73736e03 | 2583 | goto load_freelist; |
03e404af | 2584 | |
f6e7def7 | 2585 | freelist = get_freelist(s, page); |
6446faa2 | 2586 | |
6faa6833 | 2587 | if (!freelist) { |
03e404af CL |
2588 | c->page = NULL; |
2589 | stat(s, DEACTIVATE_BYPASS); | |
fc59c053 | 2590 | goto new_slab; |
03e404af | 2591 | } |
6446faa2 | 2592 | |
84e554e6 | 2593 | stat(s, ALLOC_REFILL); |
6446faa2 | 2594 | |
894b8788 | 2595 | load_freelist: |
507effea CL |
2596 | /* |
2597 | * freelist is pointing to the list of objects to be used. | |
2598 | * page is pointing to the page from which the objects are obtained. | |
2599 | * That page must be frozen for per cpu allocations to work. | |
2600 | */ | |
a0132ac0 | 2601 | VM_BUG_ON(!c->page->frozen); |
6faa6833 | 2602 | c->freelist = get_freepointer(s, freelist); |
8a5ec0ba | 2603 | c->tid = next_tid(c->tid); |
6faa6833 | 2604 | return freelist; |
81819f0f | 2605 | |
81819f0f | 2606 | new_slab: |
2cfb7455 | 2607 | |
a93cf07b WY |
2608 | if (slub_percpu_partial(c)) { |
2609 | page = c->page = slub_percpu_partial(c); | |
2610 | slub_set_percpu_partial(c, page); | |
49e22585 | 2611 | stat(s, CPU_PARTIAL_ALLOC); |
49e22585 | 2612 | goto redo; |
81819f0f CL |
2613 | } |
2614 | ||
188fd063 | 2615 | freelist = new_slab_objects(s, gfpflags, node, &c); |
01ad8a7b | 2616 | |
f4697436 | 2617 | if (unlikely(!freelist)) { |
9a02d699 | 2618 | slab_out_of_memory(s, gfpflags, node); |
f4697436 | 2619 | return NULL; |
81819f0f | 2620 | } |
2cfb7455 | 2621 | |
f6e7def7 | 2622 | page = c->page; |
5091b74a | 2623 | if (likely(!kmem_cache_debug(s) && pfmemalloc_match(page, gfpflags))) |
4b6f0750 | 2624 | goto load_freelist; |
2cfb7455 | 2625 | |
497b66f2 | 2626 | /* Only entered in the debug case */ |
d0e0ac97 CG |
2627 | if (kmem_cache_debug(s) && |
2628 | !alloc_debug_processing(s, page, freelist, addr)) | |
497b66f2 | 2629 | goto new_slab; /* Slab failed checks. Next slab needed */ |
894b8788 | 2630 | |
d4ff6d35 | 2631 | deactivate_slab(s, page, get_freepointer(s, freelist), c); |
6faa6833 | 2632 | return freelist; |
894b8788 CL |
2633 | } |
2634 | ||
a380a3c7 CL |
2635 | /* |
2636 | * Another one that disabled interrupt and compensates for possible | |
2637 | * cpu changes by refetching the per cpu area pointer. | |
2638 | */ | |
2639 | static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, | |
2640 | unsigned long addr, struct kmem_cache_cpu *c) | |
2641 | { | |
2642 | void *p; | |
2643 | unsigned long flags; | |
2644 | ||
2645 | local_irq_save(flags); | |
2646 | #ifdef CONFIG_PREEMPT | |
2647 | /* | |
2648 | * We may have been preempted and rescheduled on a different | |
2649 | * cpu before disabling interrupts. Need to reload cpu area | |
2650 | * pointer. | |
2651 | */ | |
2652 | c = this_cpu_ptr(s->cpu_slab); | |
2653 | #endif | |
2654 | ||
2655 | p = ___slab_alloc(s, gfpflags, node, addr, c); | |
2656 | local_irq_restore(flags); | |
2657 | return p; | |
2658 | } | |
2659 | ||
894b8788 CL |
2660 | /* |
2661 | * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) | |
2662 | * have the fastpath folded into their functions. So no function call | |
2663 | * overhead for requests that can be satisfied on the fastpath. | |
2664 | * | |
2665 | * The fastpath works by first checking if the lockless freelist can be used. | |
2666 | * If not then __slab_alloc is called for slow processing. | |
2667 | * | |
2668 | * Otherwise we can simply pick the next object from the lockless free list. | |
2669 | */ | |
2b847c3c | 2670 | static __always_inline void *slab_alloc_node(struct kmem_cache *s, |
ce71e27c | 2671 | gfp_t gfpflags, int node, unsigned long addr) |
894b8788 | 2672 | { |
03ec0ed5 | 2673 | void *object; |
dfb4f096 | 2674 | struct kmem_cache_cpu *c; |
57d437d2 | 2675 | struct page *page; |
8a5ec0ba | 2676 | unsigned long tid; |
1f84260c | 2677 | |
8135be5a VD |
2678 | s = slab_pre_alloc_hook(s, gfpflags); |
2679 | if (!s) | |
773ff60e | 2680 | return NULL; |
8a5ec0ba | 2681 | redo: |
8a5ec0ba CL |
2682 | /* |
2683 | * Must read kmem_cache cpu data via this cpu ptr. Preemption is | |
2684 | * enabled. We may switch back and forth between cpus while | |
2685 | * reading from one cpu area. That does not matter as long | |
2686 | * as we end up on the original cpu again when doing the cmpxchg. | |
7cccd80b | 2687 | * |
9aabf810 JK |
2688 | * We should guarantee that tid and kmem_cache are retrieved on |
2689 | * the same cpu. It could be different if CONFIG_PREEMPT so we need | |
2690 | * to check if it is matched or not. | |
8a5ec0ba | 2691 | */ |
9aabf810 JK |
2692 | do { |
2693 | tid = this_cpu_read(s->cpu_slab->tid); | |
2694 | c = raw_cpu_ptr(s->cpu_slab); | |
859b7a0e MR |
2695 | } while (IS_ENABLED(CONFIG_PREEMPT) && |
2696 | unlikely(tid != READ_ONCE(c->tid))); | |
9aabf810 JK |
2697 | |
2698 | /* | |
2699 | * Irqless object alloc/free algorithm used here depends on sequence | |
2700 | * of fetching cpu_slab's data. tid should be fetched before anything | |
2701 | * on c to guarantee that object and page associated with previous tid | |
2702 | * won't be used with current tid. If we fetch tid first, object and | |
2703 | * page could be one associated with next tid and our alloc/free | |
2704 | * request will be failed. In this case, we will retry. So, no problem. | |
2705 | */ | |
2706 | barrier(); | |
8a5ec0ba | 2707 | |
8a5ec0ba CL |
2708 | /* |
2709 | * The transaction ids are globally unique per cpu and per operation on | |
2710 | * a per cpu queue. Thus they can be guarantee that the cmpxchg_double | |
2711 | * occurs on the right processor and that there was no operation on the | |
2712 | * linked list in between. | |
2713 | */ | |
8a5ec0ba | 2714 | |
9dfc6e68 | 2715 | object = c->freelist; |
57d437d2 | 2716 | page = c->page; |
8eae1492 | 2717 | if (unlikely(!object || !node_match(page, node))) { |
dfb4f096 | 2718 | object = __slab_alloc(s, gfpflags, node, addr, c); |
8eae1492 DH |
2719 | stat(s, ALLOC_SLOWPATH); |
2720 | } else { | |
0ad9500e ED |
2721 | void *next_object = get_freepointer_safe(s, object); |
2722 | ||
8a5ec0ba | 2723 | /* |
25985edc | 2724 | * The cmpxchg will only match if there was no additional |
8a5ec0ba CL |
2725 | * operation and if we are on the right processor. |
2726 | * | |
d0e0ac97 CG |
2727 | * The cmpxchg does the following atomically (without lock |
2728 | * semantics!) | |
8a5ec0ba CL |
2729 | * 1. Relocate first pointer to the current per cpu area. |
2730 | * 2. Verify that tid and freelist have not been changed | |
2731 | * 3. If they were not changed replace tid and freelist | |
2732 | * | |
d0e0ac97 CG |
2733 | * Since this is without lock semantics the protection is only |
2734 | * against code executing on this cpu *not* from access by | |
2735 | * other cpus. | |
8a5ec0ba | 2736 | */ |
933393f5 | 2737 | if (unlikely(!this_cpu_cmpxchg_double( |
8a5ec0ba CL |
2738 | s->cpu_slab->freelist, s->cpu_slab->tid, |
2739 | object, tid, | |
0ad9500e | 2740 | next_object, next_tid(tid)))) { |
8a5ec0ba CL |
2741 | |
2742 | note_cmpxchg_failure("slab_alloc", s, tid); | |
2743 | goto redo; | |
2744 | } | |
0ad9500e | 2745 | prefetch_freepointer(s, next_object); |
84e554e6 | 2746 | stat(s, ALLOC_FASTPATH); |
894b8788 | 2747 | } |
8a5ec0ba | 2748 | |
74e2134f | 2749 | if (unlikely(gfpflags & __GFP_ZERO) && object) |
3b0efdfa | 2750 | memset(object, 0, s->object_size); |
d07dbea4 | 2751 | |
03ec0ed5 | 2752 | slab_post_alloc_hook(s, gfpflags, 1, &object); |
5a896d9e | 2753 | |
894b8788 | 2754 | return object; |
81819f0f CL |
2755 | } |
2756 | ||
2b847c3c EG |
2757 | static __always_inline void *slab_alloc(struct kmem_cache *s, |
2758 | gfp_t gfpflags, unsigned long addr) | |
2759 | { | |
2760 | return slab_alloc_node(s, gfpflags, NUMA_NO_NODE, addr); | |
2761 | } | |
2762 | ||
81819f0f CL |
2763 | void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) |
2764 | { | |
2b847c3c | 2765 | void *ret = slab_alloc(s, gfpflags, _RET_IP_); |
5b882be4 | 2766 | |
d0e0ac97 CG |
2767 | trace_kmem_cache_alloc(_RET_IP_, ret, s->object_size, |
2768 | s->size, gfpflags); | |
5b882be4 EGM |
2769 | |
2770 | return ret; | |
81819f0f CL |
2771 | } |
2772 | EXPORT_SYMBOL(kmem_cache_alloc); | |
2773 | ||
0f24f128 | 2774 | #ifdef CONFIG_TRACING |
4a92379b RK |
2775 | void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) |
2776 | { | |
2b847c3c | 2777 | void *ret = slab_alloc(s, gfpflags, _RET_IP_); |
4a92379b | 2778 | trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags); |
0116523c | 2779 | ret = kasan_kmalloc(s, ret, size, gfpflags); |
4a92379b RK |
2780 | return ret; |
2781 | } | |
2782 | EXPORT_SYMBOL(kmem_cache_alloc_trace); | |
5b882be4 EGM |
2783 | #endif |
2784 | ||
81819f0f CL |
2785 | #ifdef CONFIG_NUMA |
2786 | void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) | |
2787 | { | |
2b847c3c | 2788 | void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_); |
5b882be4 | 2789 | |
ca2b84cb | 2790 | trace_kmem_cache_alloc_node(_RET_IP_, ret, |
3b0efdfa | 2791 | s->object_size, s->size, gfpflags, node); |
5b882be4 EGM |
2792 | |
2793 | return ret; | |
81819f0f CL |
2794 | } |
2795 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
81819f0f | 2796 | |
0f24f128 | 2797 | #ifdef CONFIG_TRACING |
4a92379b | 2798 | void *kmem_cache_alloc_node_trace(struct kmem_cache *s, |
5b882be4 | 2799 | gfp_t gfpflags, |
4a92379b | 2800 | int node, size_t size) |
5b882be4 | 2801 | { |
2b847c3c | 2802 | void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_); |
4a92379b RK |
2803 | |
2804 | trace_kmalloc_node(_RET_IP_, ret, | |
2805 | size, s->size, gfpflags, node); | |
0316bec2 | 2806 | |
0116523c | 2807 | ret = kasan_kmalloc(s, ret, size, gfpflags); |
4a92379b | 2808 | return ret; |
5b882be4 | 2809 | } |
4a92379b | 2810 | EXPORT_SYMBOL(kmem_cache_alloc_node_trace); |
5b882be4 | 2811 | #endif |
5d1f57e4 | 2812 | #endif |
5b882be4 | 2813 | |
81819f0f | 2814 | /* |
94e4d712 | 2815 | * Slow path handling. This may still be called frequently since objects |
894b8788 | 2816 | * have a longer lifetime than the cpu slabs in most processing loads. |
81819f0f | 2817 | * |
894b8788 CL |
2818 | * So we still attempt to reduce cache line usage. Just take the slab |
2819 | * lock and free the item. If there is no additional partial page | |
2820 | * handling required then we can return immediately. | |
81819f0f | 2821 | */ |
894b8788 | 2822 | static void __slab_free(struct kmem_cache *s, struct page *page, |
81084651 JDB |
2823 | void *head, void *tail, int cnt, |
2824 | unsigned long addr) | |
2825 | ||
81819f0f CL |
2826 | { |
2827 | void *prior; | |
2cfb7455 | 2828 | int was_frozen; |
2cfb7455 CL |
2829 | struct page new; |
2830 | unsigned long counters; | |
2831 | struct kmem_cache_node *n = NULL; | |
61728d1e | 2832 | unsigned long uninitialized_var(flags); |
81819f0f | 2833 | |
8a5ec0ba | 2834 | stat(s, FREE_SLOWPATH); |
81819f0f | 2835 | |
19c7ff9e | 2836 | if (kmem_cache_debug(s) && |
282acb43 | 2837 | !free_debug_processing(s, page, head, tail, cnt, addr)) |
80f08c19 | 2838 | return; |
6446faa2 | 2839 | |
2cfb7455 | 2840 | do { |
837d678d JK |
2841 | if (unlikely(n)) { |
2842 | spin_unlock_irqrestore(&n->list_lock, flags); | |
2843 | n = NULL; | |
2844 | } | |
2cfb7455 CL |
2845 | prior = page->freelist; |
2846 | counters = page->counters; | |
81084651 | 2847 | set_freepointer(s, tail, prior); |
2cfb7455 CL |
2848 | new.counters = counters; |
2849 | was_frozen = new.frozen; | |
81084651 | 2850 | new.inuse -= cnt; |
837d678d | 2851 | if ((!new.inuse || !prior) && !was_frozen) { |
49e22585 | 2852 | |
c65c1877 | 2853 | if (kmem_cache_has_cpu_partial(s) && !prior) { |
49e22585 CL |
2854 | |
2855 | /* | |
d0e0ac97 CG |
2856 | * Slab was on no list before and will be |
2857 | * partially empty | |
2858 | * We can defer the list move and instead | |
2859 | * freeze it. | |
49e22585 CL |
2860 | */ |
2861 | new.frozen = 1; | |
2862 | ||
c65c1877 | 2863 | } else { /* Needs to be taken off a list */ |
49e22585 | 2864 | |
b455def2 | 2865 | n = get_node(s, page_to_nid(page)); |
49e22585 CL |
2866 | /* |
2867 | * Speculatively acquire the list_lock. | |
2868 | * If the cmpxchg does not succeed then we may | |
2869 | * drop the list_lock without any processing. | |
2870 | * | |
2871 | * Otherwise the list_lock will synchronize with | |
2872 | * other processors updating the list of slabs. | |
2873 | */ | |
2874 | spin_lock_irqsave(&n->list_lock, flags); | |
2875 | ||
2876 | } | |
2cfb7455 | 2877 | } |
81819f0f | 2878 | |
2cfb7455 CL |
2879 | } while (!cmpxchg_double_slab(s, page, |
2880 | prior, counters, | |
81084651 | 2881 | head, new.counters, |
2cfb7455 | 2882 | "__slab_free")); |
81819f0f | 2883 | |
2cfb7455 | 2884 | if (likely(!n)) { |
49e22585 CL |
2885 | |
2886 | /* | |
2887 | * If we just froze the page then put it onto the | |
2888 | * per cpu partial list. | |
2889 | */ | |
8028dcea | 2890 | if (new.frozen && !was_frozen) { |
49e22585 | 2891 | put_cpu_partial(s, page, 1); |
8028dcea AS |
2892 | stat(s, CPU_PARTIAL_FREE); |
2893 | } | |
49e22585 | 2894 | /* |
2cfb7455 CL |
2895 | * The list lock was not taken therefore no list |
2896 | * activity can be necessary. | |
2897 | */ | |
b455def2 L |
2898 | if (was_frozen) |
2899 | stat(s, FREE_FROZEN); | |
2900 | return; | |
2901 | } | |
81819f0f | 2902 | |
8a5b20ae | 2903 | if (unlikely(!new.inuse && n->nr_partial >= s->min_partial)) |
837d678d JK |
2904 | goto slab_empty; |
2905 | ||
81819f0f | 2906 | /* |
837d678d JK |
2907 | * Objects left in the slab. If it was not on the partial list before |
2908 | * then add it. | |
81819f0f | 2909 | */ |
345c905d JK |
2910 | if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { |
2911 | if (kmem_cache_debug(s)) | |
c65c1877 | 2912 | remove_full(s, n, page); |
837d678d JK |
2913 | add_partial(n, page, DEACTIVATE_TO_TAIL); |
2914 | stat(s, FREE_ADD_PARTIAL); | |
8ff12cfc | 2915 | } |
80f08c19 | 2916 | spin_unlock_irqrestore(&n->list_lock, flags); |
81819f0f CL |
2917 | return; |
2918 | ||
2919 | slab_empty: | |
a973e9dd | 2920 | if (prior) { |
81819f0f | 2921 | /* |
6fbabb20 | 2922 | * Slab on the partial list. |
81819f0f | 2923 | */ |
5cc6eee8 | 2924 | remove_partial(n, page); |
84e554e6 | 2925 | stat(s, FREE_REMOVE_PARTIAL); |
c65c1877 | 2926 | } else { |
6fbabb20 | 2927 | /* Slab must be on the full list */ |
c65c1877 PZ |
2928 | remove_full(s, n, page); |
2929 | } | |
2cfb7455 | 2930 | |
80f08c19 | 2931 | spin_unlock_irqrestore(&n->list_lock, flags); |
84e554e6 | 2932 | stat(s, FREE_SLAB); |
81819f0f | 2933 | discard_slab(s, page); |
81819f0f CL |
2934 | } |
2935 | ||
894b8788 CL |
2936 | /* |
2937 | * Fastpath with forced inlining to produce a kfree and kmem_cache_free that | |
2938 | * can perform fastpath freeing without additional function calls. | |
2939 | * | |
2940 | * The fastpath is only possible if we are freeing to the current cpu slab | |
2941 | * of this processor. This typically the case if we have just allocated | |
2942 | * the item before. | |
2943 | * | |
2944 | * If fastpath is not possible then fall back to __slab_free where we deal | |
2945 | * with all sorts of special processing. | |
81084651 JDB |
2946 | * |
2947 | * Bulk free of a freelist with several objects (all pointing to the | |
2948 | * same page) possible by specifying head and tail ptr, plus objects | |
2949 | * count (cnt). Bulk free indicated by tail pointer being set. | |
894b8788 | 2950 | */ |
80a9201a AP |
2951 | static __always_inline void do_slab_free(struct kmem_cache *s, |
2952 | struct page *page, void *head, void *tail, | |
2953 | int cnt, unsigned long addr) | |
894b8788 | 2954 | { |
81084651 | 2955 | void *tail_obj = tail ? : head; |
dfb4f096 | 2956 | struct kmem_cache_cpu *c; |
8a5ec0ba | 2957 | unsigned long tid; |
8a5ec0ba CL |
2958 | redo: |
2959 | /* | |
2960 | * Determine the currently cpus per cpu slab. | |
2961 | * The cpu may change afterward. However that does not matter since | |
2962 | * data is retrieved via this pointer. If we are on the same cpu | |
2ae44005 | 2963 | * during the cmpxchg then the free will succeed. |
8a5ec0ba | 2964 | */ |
9aabf810 JK |
2965 | do { |
2966 | tid = this_cpu_read(s->cpu_slab->tid); | |
2967 | c = raw_cpu_ptr(s->cpu_slab); | |
859b7a0e MR |
2968 | } while (IS_ENABLED(CONFIG_PREEMPT) && |
2969 | unlikely(tid != READ_ONCE(c->tid))); | |
c016b0bd | 2970 | |
9aabf810 JK |
2971 | /* Same with comment on barrier() in slab_alloc_node() */ |
2972 | barrier(); | |
c016b0bd | 2973 | |
442b06bc | 2974 | if (likely(page == c->page)) { |
81084651 | 2975 | set_freepointer(s, tail_obj, c->freelist); |
8a5ec0ba | 2976 | |
933393f5 | 2977 | if (unlikely(!this_cpu_cmpxchg_double( |
8a5ec0ba CL |
2978 | s->cpu_slab->freelist, s->cpu_slab->tid, |
2979 | c->freelist, tid, | |
81084651 | 2980 | head, next_tid(tid)))) { |
8a5ec0ba CL |
2981 | |
2982 | note_cmpxchg_failure("slab_free", s, tid); | |
2983 | goto redo; | |
2984 | } | |
84e554e6 | 2985 | stat(s, FREE_FASTPATH); |
894b8788 | 2986 | } else |
81084651 | 2987 | __slab_free(s, page, head, tail_obj, cnt, addr); |
894b8788 | 2988 | |
894b8788 CL |
2989 | } |
2990 | ||
80a9201a AP |
2991 | static __always_inline void slab_free(struct kmem_cache *s, struct page *page, |
2992 | void *head, void *tail, int cnt, | |
2993 | unsigned long addr) | |
2994 | { | |
80a9201a | 2995 | /* |
c3895391 AK |
2996 | * With KASAN enabled slab_free_freelist_hook modifies the freelist |
2997 | * to remove objects, whose reuse must be delayed. | |
80a9201a | 2998 | */ |
c3895391 AK |
2999 | if (slab_free_freelist_hook(s, &head, &tail)) |
3000 | do_slab_free(s, page, head, tail, cnt, addr); | |
80a9201a AP |
3001 | } |
3002 | ||
2bd926b4 | 3003 | #ifdef CONFIG_KASAN_GENERIC |
80a9201a AP |
3004 | void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) |
3005 | { | |
3006 | do_slab_free(cache, virt_to_head_page(x), x, NULL, 1, addr); | |
3007 | } | |
3008 | #endif | |
3009 | ||
81819f0f CL |
3010 | void kmem_cache_free(struct kmem_cache *s, void *x) |
3011 | { | |
b9ce5ef4 GC |
3012 | s = cache_from_obj(s, x); |
3013 | if (!s) | |
79576102 | 3014 | return; |
81084651 | 3015 | slab_free(s, virt_to_head_page(x), x, NULL, 1, _RET_IP_); |
ca2b84cb | 3016 | trace_kmem_cache_free(_RET_IP_, x); |
81819f0f CL |
3017 | } |
3018 | EXPORT_SYMBOL(kmem_cache_free); | |
3019 | ||
d0ecd894 | 3020 | struct detached_freelist { |
fbd02630 | 3021 | struct page *page; |
d0ecd894 JDB |
3022 | void *tail; |
3023 | void *freelist; | |
3024 | int cnt; | |
376bf125 | 3025 | struct kmem_cache *s; |
d0ecd894 | 3026 | }; |
fbd02630 | 3027 | |
d0ecd894 JDB |
3028 | /* |
3029 | * This function progressively scans the array with free objects (with | |
3030 | * a limited look ahead) and extract objects belonging to the same | |
3031 | * page. It builds a detached freelist directly within the given | |
3032 | * page/objects. This can happen without any need for | |
3033 | * synchronization, because the objects are owned by running process. | |
3034 | * The freelist is build up as a single linked list in the objects. | |
3035 | * The idea is, that this detached freelist can then be bulk | |
3036 | * transferred to the real freelist(s), but only requiring a single | |
3037 | * synchronization primitive. Look ahead in the array is limited due | |
3038 | * to performance reasons. | |
3039 | */ | |
376bf125 JDB |
3040 | static inline |
3041 | int build_detached_freelist(struct kmem_cache *s, size_t size, | |
3042 | void **p, struct detached_freelist *df) | |
d0ecd894 JDB |
3043 | { |
3044 | size_t first_skipped_index = 0; | |
3045 | int lookahead = 3; | |
3046 | void *object; | |
ca257195 | 3047 | struct page *page; |
fbd02630 | 3048 | |
d0ecd894 JDB |
3049 | /* Always re-init detached_freelist */ |
3050 | df->page = NULL; | |
fbd02630 | 3051 | |
d0ecd894 JDB |
3052 | do { |
3053 | object = p[--size]; | |
ca257195 | 3054 | /* Do we need !ZERO_OR_NULL_PTR(object) here? (for kfree) */ |
d0ecd894 | 3055 | } while (!object && size); |
3eed034d | 3056 | |
d0ecd894 JDB |
3057 | if (!object) |
3058 | return 0; | |
fbd02630 | 3059 | |
ca257195 JDB |
3060 | page = virt_to_head_page(object); |
3061 | if (!s) { | |
3062 | /* Handle kalloc'ed objects */ | |
3063 | if (unlikely(!PageSlab(page))) { | |
3064 | BUG_ON(!PageCompound(page)); | |
3065 | kfree_hook(object); | |
4949148a | 3066 | __free_pages(page, compound_order(page)); |
ca257195 JDB |
3067 | p[size] = NULL; /* mark object processed */ |
3068 | return size; | |
3069 | } | |
3070 | /* Derive kmem_cache from object */ | |
3071 | df->s = page->slab_cache; | |
3072 | } else { | |
3073 | df->s = cache_from_obj(s, object); /* Support for memcg */ | |
3074 | } | |
376bf125 | 3075 | |
d0ecd894 | 3076 | /* Start new detached freelist */ |
ca257195 | 3077 | df->page = page; |
376bf125 | 3078 | set_freepointer(df->s, object, NULL); |
d0ecd894 JDB |
3079 | df->tail = object; |
3080 | df->freelist = object; | |
3081 | p[size] = NULL; /* mark object processed */ | |
3082 | df->cnt = 1; | |
3083 | ||
3084 | while (size) { | |
3085 | object = p[--size]; | |
3086 | if (!object) | |
3087 | continue; /* Skip processed objects */ | |
3088 | ||
3089 | /* df->page is always set at this point */ | |
3090 | if (df->page == virt_to_head_page(object)) { | |
3091 | /* Opportunity build freelist */ | |
376bf125 | 3092 | set_freepointer(df->s, object, df->freelist); |
d0ecd894 JDB |
3093 | df->freelist = object; |
3094 | df->cnt++; | |
3095 | p[size] = NULL; /* mark object processed */ | |
3096 | ||
3097 | continue; | |
fbd02630 | 3098 | } |
d0ecd894 JDB |
3099 | |
3100 | /* Limit look ahead search */ | |
3101 | if (!--lookahead) | |
3102 | break; | |
3103 | ||
3104 | if (!first_skipped_index) | |
3105 | first_skipped_index = size + 1; | |
fbd02630 | 3106 | } |
d0ecd894 JDB |
3107 | |
3108 | return first_skipped_index; | |
3109 | } | |
3110 | ||
d0ecd894 | 3111 | /* Note that interrupts must be enabled when calling this function. */ |
376bf125 | 3112 | void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) |
d0ecd894 JDB |
3113 | { |
3114 | if (WARN_ON(!size)) | |
3115 | return; | |
3116 | ||
3117 | do { | |
3118 | struct detached_freelist df; | |
3119 | ||
3120 | size = build_detached_freelist(s, size, p, &df); | |
84582c8a | 3121 | if (!df.page) |
d0ecd894 JDB |
3122 | continue; |
3123 | ||
376bf125 | 3124 | slab_free(df.s, df.page, df.freelist, df.tail, df.cnt,_RET_IP_); |
d0ecd894 | 3125 | } while (likely(size)); |
484748f0 CL |
3126 | } |
3127 | EXPORT_SYMBOL(kmem_cache_free_bulk); | |
3128 | ||
994eb764 | 3129 | /* Note that interrupts must be enabled when calling this function. */ |
865762a8 JDB |
3130 | int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, |
3131 | void **p) | |
484748f0 | 3132 | { |
994eb764 JDB |
3133 | struct kmem_cache_cpu *c; |
3134 | int i; | |
3135 | ||
03ec0ed5 JDB |
3136 | /* memcg and kmem_cache debug support */ |
3137 | s = slab_pre_alloc_hook(s, flags); | |
3138 | if (unlikely(!s)) | |
3139 | return false; | |
994eb764 JDB |
3140 | /* |
3141 | * Drain objects in the per cpu slab, while disabling local | |
3142 | * IRQs, which protects against PREEMPT and interrupts | |
3143 | * handlers invoking normal fastpath. | |
3144 | */ | |
3145 | local_irq_disable(); | |
3146 | c = this_cpu_ptr(s->cpu_slab); | |
3147 | ||
3148 | for (i = 0; i < size; i++) { | |
3149 | void *object = c->freelist; | |
3150 | ||
ebe909e0 | 3151 | if (unlikely(!object)) { |
ebe909e0 JDB |
3152 | /* |
3153 | * Invoking slow path likely have side-effect | |
3154 | * of re-populating per CPU c->freelist | |
3155 | */ | |
87098373 | 3156 | p[i] = ___slab_alloc(s, flags, NUMA_NO_NODE, |
ebe909e0 | 3157 | _RET_IP_, c); |
87098373 CL |
3158 | if (unlikely(!p[i])) |
3159 | goto error; | |
3160 | ||
ebe909e0 JDB |
3161 | c = this_cpu_ptr(s->cpu_slab); |
3162 | continue; /* goto for-loop */ | |
3163 | } | |
994eb764 JDB |
3164 | c->freelist = get_freepointer(s, object); |
3165 | p[i] = object; | |
3166 | } | |
3167 | c->tid = next_tid(c->tid); | |
3168 | local_irq_enable(); | |
3169 | ||
3170 | /* Clear memory outside IRQ disabled fastpath loop */ | |
3171 | if (unlikely(flags & __GFP_ZERO)) { | |
3172 | int j; | |
3173 | ||
3174 | for (j = 0; j < i; j++) | |
3175 | memset(p[j], 0, s->object_size); | |
3176 | } | |
3177 | ||
03ec0ed5 JDB |
3178 | /* memcg and kmem_cache debug support */ |
3179 | slab_post_alloc_hook(s, flags, size, p); | |
865762a8 | 3180 | return i; |
87098373 | 3181 | error: |
87098373 | 3182 | local_irq_enable(); |
03ec0ed5 JDB |
3183 | slab_post_alloc_hook(s, flags, i, p); |
3184 | __kmem_cache_free_bulk(s, i, p); | |
865762a8 | 3185 | return 0; |
484748f0 CL |
3186 | } |
3187 | EXPORT_SYMBOL(kmem_cache_alloc_bulk); | |
3188 | ||
3189 | ||
81819f0f | 3190 | /* |
672bba3a CL |
3191 | * Object placement in a slab is made very easy because we always start at |
3192 | * offset 0. If we tune the size of the object to the alignment then we can | |
3193 | * get the required alignment by putting one properly sized object after | |
3194 | * another. | |
81819f0f CL |
3195 | * |
3196 | * Notice that the allocation order determines the sizes of the per cpu | |
3197 | * caches. Each processor has always one slab available for allocations. | |
3198 | * Increasing the allocation order reduces the number of times that slabs | |
672bba3a | 3199 | * must be moved on and off the partial lists and is therefore a factor in |
81819f0f | 3200 | * locking overhead. |
81819f0f CL |
3201 | */ |
3202 | ||
3203 | /* | |
3204 | * Mininum / Maximum order of slab pages. This influences locking overhead | |
3205 | * and slab fragmentation. A higher order reduces the number of partial slabs | |
3206 | * and increases the number of allocations possible without having to | |
3207 | * take the list_lock. | |
3208 | */ | |
19af27af AD |
3209 | static unsigned int slub_min_order; |
3210 | static unsigned int slub_max_order = PAGE_ALLOC_COSTLY_ORDER; | |
3211 | static unsigned int slub_min_objects; | |
81819f0f | 3212 | |
81819f0f CL |
3213 | /* |
3214 | * Calculate the order of allocation given an slab object size. | |
3215 | * | |
672bba3a CL |
3216 | * The order of allocation has significant impact on performance and other |
3217 | * system components. Generally order 0 allocations should be preferred since | |
3218 | * order 0 does not cause fragmentation in the page allocator. Larger objects | |
3219 | * be problematic to put into order 0 slabs because there may be too much | |
c124f5b5 | 3220 | * unused space left. We go to a higher order if more than 1/16th of the slab |
672bba3a CL |
3221 | * would be wasted. |
3222 | * | |
3223 | * In order to reach satisfactory performance we must ensure that a minimum | |
3224 | * number of objects is in one slab. Otherwise we may generate too much | |
3225 | * activity on the partial lists which requires taking the list_lock. This is | |
3226 | * less a concern for large slabs though which are rarely used. | |
81819f0f | 3227 | * |
672bba3a CL |
3228 | * slub_max_order specifies the order where we begin to stop considering the |
3229 | * number of objects in a slab as critical. If we reach slub_max_order then | |
3230 | * we try to keep the page order as low as possible. So we accept more waste | |
3231 | * of space in favor of a small page order. | |
81819f0f | 3232 | * |
672bba3a CL |
3233 | * Higher order allocations also allow the placement of more objects in a |
3234 | * slab and thereby reduce object handling overhead. If the user has | |
3235 | * requested a higher mininum order then we start with that one instead of | |
3236 | * the smallest order which will fit the object. | |
81819f0f | 3237 | */ |
19af27af AD |
3238 | static inline unsigned int slab_order(unsigned int size, |
3239 | unsigned int min_objects, unsigned int max_order, | |
9736d2a9 | 3240 | unsigned int fract_leftover) |
81819f0f | 3241 | { |
19af27af AD |
3242 | unsigned int min_order = slub_min_order; |
3243 | unsigned int order; | |
81819f0f | 3244 | |
9736d2a9 | 3245 | if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) |
210b5c06 | 3246 | return get_order(size * MAX_OBJS_PER_PAGE) - 1; |
39b26464 | 3247 | |
9736d2a9 | 3248 | for (order = max(min_order, (unsigned int)get_order(min_objects * size)); |
5e6d444e | 3249 | order <= max_order; order++) { |
81819f0f | 3250 | |
19af27af AD |
3251 | unsigned int slab_size = (unsigned int)PAGE_SIZE << order; |
3252 | unsigned int rem; | |
81819f0f | 3253 | |
9736d2a9 | 3254 | rem = slab_size % size; |
81819f0f | 3255 | |
5e6d444e | 3256 | if (rem <= slab_size / fract_leftover) |
81819f0f | 3257 | break; |
81819f0f | 3258 | } |
672bba3a | 3259 | |
81819f0f CL |
3260 | return order; |
3261 | } | |
3262 | ||
9736d2a9 | 3263 | static inline int calculate_order(unsigned int size) |
5e6d444e | 3264 | { |
19af27af AD |
3265 | unsigned int order; |
3266 | unsigned int min_objects; | |
3267 | unsigned int max_objects; | |
5e6d444e CL |
3268 | |
3269 | /* | |
3270 | * Attempt to find best configuration for a slab. This | |
3271 | * works by first attempting to generate a layout with | |
3272 | * the best configuration and backing off gradually. | |
3273 | * | |
422ff4d7 | 3274 | * First we increase the acceptable waste in a slab. Then |
5e6d444e CL |
3275 | * we reduce the minimum objects required in a slab. |
3276 | */ | |
3277 | min_objects = slub_min_objects; | |
9b2cd506 CL |
3278 | if (!min_objects) |
3279 | min_objects = 4 * (fls(nr_cpu_ids) + 1); | |
9736d2a9 | 3280 | max_objects = order_objects(slub_max_order, size); |
e8120ff1 ZY |
3281 | min_objects = min(min_objects, max_objects); |
3282 | ||
5e6d444e | 3283 | while (min_objects > 1) { |
19af27af AD |
3284 | unsigned int fraction; |
3285 | ||
c124f5b5 | 3286 | fraction = 16; |
5e6d444e CL |
3287 | while (fraction >= 4) { |
3288 | order = slab_order(size, min_objects, | |
9736d2a9 | 3289 | slub_max_order, fraction); |
5e6d444e CL |
3290 | if (order <= slub_max_order) |
3291 | return order; | |
3292 | fraction /= 2; | |
3293 | } | |
5086c389 | 3294 | min_objects--; |
5e6d444e CL |
3295 | } |
3296 | ||
3297 | /* | |
3298 | * We were unable to place multiple objects in a slab. Now | |
3299 | * lets see if we can place a single object there. | |
3300 | */ | |
9736d2a9 | 3301 | order = slab_order(size, 1, slub_max_order, 1); |
5e6d444e CL |
3302 | if (order <= slub_max_order) |
3303 | return order; | |
3304 | ||
3305 | /* | |
3306 | * Doh this slab cannot be placed using slub_max_order. | |
3307 | */ | |
9736d2a9 | 3308 | order = slab_order(size, 1, MAX_ORDER, 1); |
818cf590 | 3309 | if (order < MAX_ORDER) |
5e6d444e CL |
3310 | return order; |
3311 | return -ENOSYS; | |
3312 | } | |
3313 | ||
5595cffc | 3314 | static void |
4053497d | 3315 | init_kmem_cache_node(struct kmem_cache_node *n) |
81819f0f CL |
3316 | { |
3317 | n->nr_partial = 0; | |
81819f0f CL |
3318 | spin_lock_init(&n->list_lock); |
3319 | INIT_LIST_HEAD(&n->partial); | |
8ab1372f | 3320 | #ifdef CONFIG_SLUB_DEBUG |
0f389ec6 | 3321 | atomic_long_set(&n->nr_slabs, 0); |
02b71b70 | 3322 | atomic_long_set(&n->total_objects, 0); |
643b1138 | 3323 | INIT_LIST_HEAD(&n->full); |
8ab1372f | 3324 | #endif |
81819f0f CL |
3325 | } |
3326 | ||
55136592 | 3327 | static inline int alloc_kmem_cache_cpus(struct kmem_cache *s) |
4c93c355 | 3328 | { |
6c182dc0 | 3329 | BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < |
95a05b42 | 3330 | KMALLOC_SHIFT_HIGH * sizeof(struct kmem_cache_cpu)); |
4c93c355 | 3331 | |
8a5ec0ba | 3332 | /* |
d4d84fef CM |
3333 | * Must align to double word boundary for the double cmpxchg |
3334 | * instructions to work; see __pcpu_double_call_return_bool(). | |
8a5ec0ba | 3335 | */ |
d4d84fef CM |
3336 | s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu), |
3337 | 2 * sizeof(void *)); | |
8a5ec0ba CL |
3338 | |
3339 | if (!s->cpu_slab) | |
3340 | return 0; | |
3341 | ||
3342 | init_kmem_cache_cpus(s); | |
4c93c355 | 3343 | |
8a5ec0ba | 3344 | return 1; |
4c93c355 | 3345 | } |
4c93c355 | 3346 | |
51df1142 CL |
3347 | static struct kmem_cache *kmem_cache_node; |
3348 | ||
81819f0f CL |
3349 | /* |
3350 | * No kmalloc_node yet so do it by hand. We know that this is the first | |
3351 | * slab on the node for this slabcache. There are no concurrent accesses | |
3352 | * possible. | |
3353 | * | |
721ae22a ZYW |
3354 | * Note that this function only works on the kmem_cache_node |
3355 | * when allocating for the kmem_cache_node. This is used for bootstrapping | |
4c93c355 | 3356 | * memory on a fresh node that has no slab structures yet. |
81819f0f | 3357 | */ |
55136592 | 3358 | static void early_kmem_cache_node_alloc(int node) |
81819f0f CL |
3359 | { |
3360 | struct page *page; | |
3361 | struct kmem_cache_node *n; | |
3362 | ||
51df1142 | 3363 | BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node)); |
81819f0f | 3364 | |
51df1142 | 3365 | page = new_slab(kmem_cache_node, GFP_NOWAIT, node); |
81819f0f CL |
3366 | |
3367 | BUG_ON(!page); | |
a2f92ee7 | 3368 | if (page_to_nid(page) != node) { |
f9f58285 FF |
3369 | pr_err("SLUB: Unable to allocate memory from node %d\n", node); |
3370 | pr_err("SLUB: Allocating a useless per node structure in order to be able to continue\n"); | |
a2f92ee7 CL |
3371 | } |
3372 | ||
81819f0f CL |
3373 | n = page->freelist; |
3374 | BUG_ON(!n); | |
8ab1372f | 3375 | #ifdef CONFIG_SLUB_DEBUG |
f7cb1933 | 3376 | init_object(kmem_cache_node, n, SLUB_RED_ACTIVE); |
51df1142 | 3377 | init_tracking(kmem_cache_node, n); |
8ab1372f | 3378 | #endif |
12b22386 | 3379 | n = kasan_kmalloc(kmem_cache_node, n, sizeof(struct kmem_cache_node), |
505f5dcb | 3380 | GFP_KERNEL); |
12b22386 AK |
3381 | page->freelist = get_freepointer(kmem_cache_node, n); |
3382 | page->inuse = 1; | |
3383 | page->frozen = 0; | |
3384 | kmem_cache_node->node[node] = n; | |
4053497d | 3385 | init_kmem_cache_node(n); |
51df1142 | 3386 | inc_slabs_node(kmem_cache_node, node, page->objects); |
6446faa2 | 3387 | |
67b6c900 | 3388 | /* |
1e4dd946 SR |
3389 | * No locks need to be taken here as it has just been |
3390 | * initialized and there is no concurrent access. | |
67b6c900 | 3391 | */ |
1e4dd946 | 3392 | __add_partial(n, page, DEACTIVATE_TO_HEAD); |
81819f0f CL |
3393 | } |
3394 | ||
3395 | static void free_kmem_cache_nodes(struct kmem_cache *s) | |
3396 | { | |
3397 | int node; | |
fa45dc25 | 3398 | struct kmem_cache_node *n; |
81819f0f | 3399 | |
fa45dc25 | 3400 | for_each_kmem_cache_node(s, node, n) { |
81819f0f | 3401 | s->node[node] = NULL; |
ea37df54 | 3402 | kmem_cache_free(kmem_cache_node, n); |
81819f0f CL |
3403 | } |
3404 | } | |
3405 | ||
52b4b950 DS |
3406 | void __kmem_cache_release(struct kmem_cache *s) |
3407 | { | |
210e7a43 | 3408 | cache_random_seq_destroy(s); |
52b4b950 DS |
3409 | free_percpu(s->cpu_slab); |
3410 | free_kmem_cache_nodes(s); | |
3411 | } | |
3412 | ||
55136592 | 3413 | static int init_kmem_cache_nodes(struct kmem_cache *s) |
81819f0f CL |
3414 | { |
3415 | int node; | |
81819f0f | 3416 | |
f64dc58c | 3417 | for_each_node_state(node, N_NORMAL_MEMORY) { |
81819f0f CL |
3418 | struct kmem_cache_node *n; |
3419 | ||
73367bd8 | 3420 | if (slab_state == DOWN) { |
55136592 | 3421 | early_kmem_cache_node_alloc(node); |
73367bd8 AD |
3422 | continue; |
3423 | } | |
51df1142 | 3424 | n = kmem_cache_alloc_node(kmem_cache_node, |
55136592 | 3425 | GFP_KERNEL, node); |
81819f0f | 3426 | |
73367bd8 AD |
3427 | if (!n) { |
3428 | free_kmem_cache_nodes(s); | |
3429 | return 0; | |
81819f0f | 3430 | } |
73367bd8 | 3431 | |
4053497d | 3432 | init_kmem_cache_node(n); |
ea37df54 | 3433 | s->node[node] = n; |
81819f0f CL |
3434 | } |
3435 | return 1; | |
3436 | } | |
81819f0f | 3437 | |
c0bdb232 | 3438 | static void set_min_partial(struct kmem_cache *s, unsigned long min) |
3b89d7d8 DR |
3439 | { |
3440 | if (min < MIN_PARTIAL) | |
3441 | min = MIN_PARTIAL; | |
3442 | else if (min > MAX_PARTIAL) | |
3443 | min = MAX_PARTIAL; | |
3444 | s->min_partial = min; | |
3445 | } | |
3446 | ||
e6d0e1dc WY |
3447 | static void set_cpu_partial(struct kmem_cache *s) |
3448 | { | |
3449 | #ifdef CONFIG_SLUB_CPU_PARTIAL | |
3450 | /* | |
3451 | * cpu_partial determined the maximum number of objects kept in the | |
3452 | * per cpu partial lists of a processor. | |
3453 | * | |
3454 | * Per cpu partial lists mainly contain slabs that just have one | |
3455 | * object freed. If they are used for allocation then they can be | |
3456 | * filled up again with minimal effort. The slab will never hit the | |
3457 | * per node partial lists and therefore no locking will be required. | |
3458 | * | |
3459 | * This setting also determines | |
3460 | * | |
3461 | * A) The number of objects from per cpu partial slabs dumped to the | |
3462 | * per node list when we reach the limit. | |
3463 | * B) The number of objects in cpu partial slabs to extract from the | |
3464 | * per node list when we run out of per cpu objects. We only fetch | |
3465 | * 50% to keep some capacity around for frees. | |
3466 | */ | |
3467 | if (!kmem_cache_has_cpu_partial(s)) | |
3468 | s->cpu_partial = 0; | |
3469 | else if (s->size >= PAGE_SIZE) | |
3470 | s->cpu_partial = 2; | |
3471 | else if (s->size >= 1024) | |
3472 | s->cpu_partial = 6; | |
3473 | else if (s->size >= 256) | |
3474 | s->cpu_partial = 13; | |
3475 | else | |
3476 | s->cpu_partial = 30; | |
3477 | #endif | |
3478 | } | |
3479 | ||
81819f0f CL |
3480 | /* |
3481 | * calculate_sizes() determines the order and the distribution of data within | |
3482 | * a slab object. | |
3483 | */ | |
06b285dc | 3484 | static int calculate_sizes(struct kmem_cache *s, int forced_order) |
81819f0f | 3485 | { |
d50112ed | 3486 | slab_flags_t flags = s->flags; |
be4a7988 | 3487 | unsigned int size = s->object_size; |
19af27af | 3488 | unsigned int order; |
81819f0f | 3489 | |
d8b42bf5 CL |
3490 | /* |
3491 | * Round up object size to the next word boundary. We can only | |
3492 | * place the free pointer at word boundaries and this determines | |
3493 | * the possible location of the free pointer. | |
3494 | */ | |
3495 | size = ALIGN(size, sizeof(void *)); | |
3496 | ||
3497 | #ifdef CONFIG_SLUB_DEBUG | |
81819f0f CL |
3498 | /* |
3499 | * Determine if we can poison the object itself. If the user of | |
3500 | * the slab may touch the object after free or before allocation | |
3501 | * then we should never poison the object itself. | |
3502 | */ | |
5f0d5a3a | 3503 | if ((flags & SLAB_POISON) && !(flags & SLAB_TYPESAFE_BY_RCU) && |
c59def9f | 3504 | !s->ctor) |
81819f0f CL |
3505 | s->flags |= __OBJECT_POISON; |
3506 | else | |
3507 | s->flags &= ~__OBJECT_POISON; | |
3508 | ||
81819f0f CL |
3509 | |
3510 | /* | |
672bba3a | 3511 | * If we are Redzoning then check if there is some space between the |
81819f0f | 3512 | * end of the object and the free pointer. If not then add an |
672bba3a | 3513 | * additional word to have some bytes to store Redzone information. |
81819f0f | 3514 | */ |
3b0efdfa | 3515 | if ((flags & SLAB_RED_ZONE) && size == s->object_size) |
81819f0f | 3516 | size += sizeof(void *); |
41ecc55b | 3517 | #endif |
81819f0f CL |
3518 | |
3519 | /* | |
672bba3a CL |
3520 | * With that we have determined the number of bytes in actual use |
3521 | * by the object. This is the potential offset to the free pointer. | |
81819f0f CL |
3522 | */ |
3523 | s->inuse = size; | |
3524 | ||
5f0d5a3a | 3525 | if (((flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) || |
c59def9f | 3526 | s->ctor)) { |
81819f0f CL |
3527 | /* |
3528 | * Relocate free pointer after the object if it is not | |
3529 | * permitted to overwrite the first word of the object on | |
3530 | * kmem_cache_free. | |
3531 | * | |
3532 | * This is the case if we do RCU, have a constructor or | |
3533 | * destructor or are poisoning the objects. | |
3534 | */ | |
3535 | s->offset = size; | |
3536 | size += sizeof(void *); | |
3537 | } | |
3538 | ||
c12b3c62 | 3539 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
3540 | if (flags & SLAB_STORE_USER) |
3541 | /* | |
3542 | * Need to store information about allocs and frees after | |
3543 | * the object. | |
3544 | */ | |
3545 | size += 2 * sizeof(struct track); | |
80a9201a | 3546 | #endif |
81819f0f | 3547 | |
80a9201a AP |
3548 | kasan_cache_create(s, &size, &s->flags); |
3549 | #ifdef CONFIG_SLUB_DEBUG | |
d86bd1be | 3550 | if (flags & SLAB_RED_ZONE) { |
81819f0f CL |
3551 | /* |
3552 | * Add some empty padding so that we can catch | |
3553 | * overwrites from earlier objects rather than let | |
3554 | * tracking information or the free pointer be | |
0211a9c8 | 3555 | * corrupted if a user writes before the start |
81819f0f CL |
3556 | * of the object. |
3557 | */ | |
3558 | size += sizeof(void *); | |
d86bd1be JK |
3559 | |
3560 | s->red_left_pad = sizeof(void *); | |
3561 | s->red_left_pad = ALIGN(s->red_left_pad, s->align); | |
3562 | size += s->red_left_pad; | |
3563 | } | |
41ecc55b | 3564 | #endif |
672bba3a | 3565 | |
81819f0f CL |
3566 | /* |
3567 | * SLUB stores one object immediately after another beginning from | |
3568 | * offset 0. In order to align the objects we have to simply size | |
3569 | * each object to conform to the alignment. | |
3570 | */ | |
45906855 | 3571 | size = ALIGN(size, s->align); |
81819f0f | 3572 | s->size = size; |
06b285dc CL |
3573 | if (forced_order >= 0) |
3574 | order = forced_order; | |
3575 | else | |
9736d2a9 | 3576 | order = calculate_order(size); |
81819f0f | 3577 | |
19af27af | 3578 | if ((int)order < 0) |
81819f0f CL |
3579 | return 0; |
3580 | ||
b7a49f0d | 3581 | s->allocflags = 0; |
834f3d11 | 3582 | if (order) |
b7a49f0d CL |
3583 | s->allocflags |= __GFP_COMP; |
3584 | ||
3585 | if (s->flags & SLAB_CACHE_DMA) | |
2c59dd65 | 3586 | s->allocflags |= GFP_DMA; |
b7a49f0d CL |
3587 | |
3588 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
3589 | s->allocflags |= __GFP_RECLAIMABLE; | |
3590 | ||
81819f0f CL |
3591 | /* |
3592 | * Determine the number of objects per slab | |
3593 | */ | |
9736d2a9 MW |
3594 | s->oo = oo_make(order, size); |
3595 | s->min = oo_make(get_order(size), size); | |
205ab99d CL |
3596 | if (oo_objects(s->oo) > oo_objects(s->max)) |
3597 | s->max = s->oo; | |
81819f0f | 3598 | |
834f3d11 | 3599 | return !!oo_objects(s->oo); |
81819f0f CL |
3600 | } |
3601 | ||
d50112ed | 3602 | static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags) |
81819f0f | 3603 | { |
8a13a4cc | 3604 | s->flags = kmem_cache_flags(s->size, flags, s->name, s->ctor); |
2482ddec KC |
3605 | #ifdef CONFIG_SLAB_FREELIST_HARDENED |
3606 | s->random = get_random_long(); | |
3607 | #endif | |
81819f0f | 3608 | |
06b285dc | 3609 | if (!calculate_sizes(s, -1)) |
81819f0f | 3610 | goto error; |
3de47213 DR |
3611 | if (disable_higher_order_debug) { |
3612 | /* | |
3613 | * Disable debugging flags that store metadata if the min slab | |
3614 | * order increased. | |
3615 | */ | |
3b0efdfa | 3616 | if (get_order(s->size) > get_order(s->object_size)) { |
3de47213 DR |
3617 | s->flags &= ~DEBUG_METADATA_FLAGS; |
3618 | s->offset = 0; | |
3619 | if (!calculate_sizes(s, -1)) | |
3620 | goto error; | |
3621 | } | |
3622 | } | |
81819f0f | 3623 | |
2565409f HC |
3624 | #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
3625 | defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) | |
149daaf3 | 3626 | if (system_has_cmpxchg_double() && (s->flags & SLAB_NO_CMPXCHG) == 0) |
b789ef51 CL |
3627 | /* Enable fast mode */ |
3628 | s->flags |= __CMPXCHG_DOUBLE; | |
3629 | #endif | |
3630 | ||
3b89d7d8 DR |
3631 | /* |
3632 | * The larger the object size is, the more pages we want on the partial | |
3633 | * list to avoid pounding the page allocator excessively. | |
3634 | */ | |
49e22585 CL |
3635 | set_min_partial(s, ilog2(s->size) / 2); |
3636 | ||
e6d0e1dc | 3637 | set_cpu_partial(s); |
49e22585 | 3638 | |
81819f0f | 3639 | #ifdef CONFIG_NUMA |
e2cb96b7 | 3640 | s->remote_node_defrag_ratio = 1000; |
81819f0f | 3641 | #endif |
210e7a43 TG |
3642 | |
3643 | /* Initialize the pre-computed randomized freelist if slab is up */ | |
3644 | if (slab_state >= UP) { | |
3645 | if (init_cache_random_seq(s)) | |
3646 | goto error; | |
3647 | } | |
3648 | ||
55136592 | 3649 | if (!init_kmem_cache_nodes(s)) |
dfb4f096 | 3650 | goto error; |
81819f0f | 3651 | |
55136592 | 3652 | if (alloc_kmem_cache_cpus(s)) |
278b1bb1 | 3653 | return 0; |
ff12059e | 3654 | |
4c93c355 | 3655 | free_kmem_cache_nodes(s); |
81819f0f CL |
3656 | error: |
3657 | if (flags & SLAB_PANIC) | |
44065b2e AD |
3658 | panic("Cannot create slab %s size=%u realsize=%u order=%u offset=%u flags=%lx\n", |
3659 | s->name, s->size, s->size, | |
4fd0b46e | 3660 | oo_order(s->oo), s->offset, (unsigned long)flags); |
278b1bb1 | 3661 | return -EINVAL; |
81819f0f | 3662 | } |
81819f0f | 3663 | |
33b12c38 CL |
3664 | static void list_slab_objects(struct kmem_cache *s, struct page *page, |
3665 | const char *text) | |
3666 | { | |
3667 | #ifdef CONFIG_SLUB_DEBUG | |
3668 | void *addr = page_address(page); | |
3669 | void *p; | |
0684e652 | 3670 | unsigned long *map = bitmap_zalloc(page->objects, GFP_ATOMIC); |
bbd7d57b ED |
3671 | if (!map) |
3672 | return; | |
945cf2b6 | 3673 | slab_err(s, page, text, s->name); |
33b12c38 | 3674 | slab_lock(page); |
33b12c38 | 3675 | |
5f80b13a | 3676 | get_map(s, page, map); |
33b12c38 CL |
3677 | for_each_object(p, s, addr, page->objects) { |
3678 | ||
3679 | if (!test_bit(slab_index(p, s, addr), map)) { | |
f9f58285 | 3680 | pr_err("INFO: Object 0x%p @offset=%tu\n", p, p - addr); |
33b12c38 CL |
3681 | print_tracking(s, p); |
3682 | } | |
3683 | } | |
3684 | slab_unlock(page); | |
0684e652 | 3685 | bitmap_free(map); |
33b12c38 CL |
3686 | #endif |
3687 | } | |
3688 | ||
81819f0f | 3689 | /* |
599870b1 | 3690 | * Attempt to free all partial slabs on a node. |
52b4b950 DS |
3691 | * This is called from __kmem_cache_shutdown(). We must take list_lock |
3692 | * because sysfs file might still access partial list after the shutdowning. | |
81819f0f | 3693 | */ |
599870b1 | 3694 | static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) |
81819f0f | 3695 | { |
60398923 | 3696 | LIST_HEAD(discard); |
81819f0f CL |
3697 | struct page *page, *h; |
3698 | ||
52b4b950 DS |
3699 | BUG_ON(irqs_disabled()); |
3700 | spin_lock_irq(&n->list_lock); | |
33b12c38 | 3701 | list_for_each_entry_safe(page, h, &n->partial, lru) { |
81819f0f | 3702 | if (!page->inuse) { |
52b4b950 | 3703 | remove_partial(n, page); |
60398923 | 3704 | list_add(&page->lru, &discard); |
33b12c38 CL |
3705 | } else { |
3706 | list_slab_objects(s, page, | |
52b4b950 | 3707 | "Objects remaining in %s on __kmem_cache_shutdown()"); |
599870b1 | 3708 | } |
33b12c38 | 3709 | } |
52b4b950 | 3710 | spin_unlock_irq(&n->list_lock); |
60398923 CW |
3711 | |
3712 | list_for_each_entry_safe(page, h, &discard, lru) | |
3713 | discard_slab(s, page); | |
81819f0f CL |
3714 | } |
3715 | ||
f9e13c0a SB |
3716 | bool __kmem_cache_empty(struct kmem_cache *s) |
3717 | { | |
3718 | int node; | |
3719 | struct kmem_cache_node *n; | |
3720 | ||
3721 | for_each_kmem_cache_node(s, node, n) | |
3722 | if (n->nr_partial || slabs_node(s, node)) | |
3723 | return false; | |
3724 | return true; | |
3725 | } | |
3726 | ||
81819f0f | 3727 | /* |
672bba3a | 3728 | * Release all resources used by a slab cache. |
81819f0f | 3729 | */ |
52b4b950 | 3730 | int __kmem_cache_shutdown(struct kmem_cache *s) |
81819f0f CL |
3731 | { |
3732 | int node; | |
fa45dc25 | 3733 | struct kmem_cache_node *n; |
81819f0f CL |
3734 | |
3735 | flush_all(s); | |
81819f0f | 3736 | /* Attempt to free all objects */ |
fa45dc25 | 3737 | for_each_kmem_cache_node(s, node, n) { |
599870b1 CL |
3738 | free_partial(s, n); |
3739 | if (n->nr_partial || slabs_node(s, node)) | |
81819f0f CL |
3740 | return 1; |
3741 | } | |
bf5eb3de | 3742 | sysfs_slab_remove(s); |
81819f0f CL |
3743 | return 0; |
3744 | } | |
3745 | ||
81819f0f CL |
3746 | /******************************************************************** |
3747 | * Kmalloc subsystem | |
3748 | *******************************************************************/ | |
3749 | ||
81819f0f CL |
3750 | static int __init setup_slub_min_order(char *str) |
3751 | { | |
19af27af | 3752 | get_option(&str, (int *)&slub_min_order); |
81819f0f CL |
3753 | |
3754 | return 1; | |
3755 | } | |
3756 | ||
3757 | __setup("slub_min_order=", setup_slub_min_order); | |
3758 | ||
3759 | static int __init setup_slub_max_order(char *str) | |
3760 | { | |
19af27af AD |
3761 | get_option(&str, (int *)&slub_max_order); |
3762 | slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); | |
81819f0f CL |
3763 | |
3764 | return 1; | |
3765 | } | |
3766 | ||
3767 | __setup("slub_max_order=", setup_slub_max_order); | |
3768 | ||
3769 | static int __init setup_slub_min_objects(char *str) | |
3770 | { | |
19af27af | 3771 | get_option(&str, (int *)&slub_min_objects); |
81819f0f CL |
3772 | |
3773 | return 1; | |
3774 | } | |
3775 | ||
3776 | __setup("slub_min_objects=", setup_slub_min_objects); | |
3777 | ||
81819f0f CL |
3778 | void *__kmalloc(size_t size, gfp_t flags) |
3779 | { | |
aadb4bc4 | 3780 | struct kmem_cache *s; |
5b882be4 | 3781 | void *ret; |
81819f0f | 3782 | |
95a05b42 | 3783 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) |
eada35ef | 3784 | return kmalloc_large(size, flags); |
aadb4bc4 | 3785 | |
2c59dd65 | 3786 | s = kmalloc_slab(size, flags); |
aadb4bc4 CL |
3787 | |
3788 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
3789 | return s; |
3790 | ||
2b847c3c | 3791 | ret = slab_alloc(s, flags, _RET_IP_); |
5b882be4 | 3792 | |
ca2b84cb | 3793 | trace_kmalloc(_RET_IP_, ret, size, s->size, flags); |
5b882be4 | 3794 | |
0116523c | 3795 | ret = kasan_kmalloc(s, ret, size, flags); |
0316bec2 | 3796 | |
5b882be4 | 3797 | return ret; |
81819f0f CL |
3798 | } |
3799 | EXPORT_SYMBOL(__kmalloc); | |
3800 | ||
5d1f57e4 | 3801 | #ifdef CONFIG_NUMA |
f619cfe1 CL |
3802 | static void *kmalloc_large_node(size_t size, gfp_t flags, int node) |
3803 | { | |
b1eeab67 | 3804 | struct page *page; |
e4f7c0b4 | 3805 | void *ptr = NULL; |
f619cfe1 | 3806 | |
75f296d9 | 3807 | flags |= __GFP_COMP; |
4949148a | 3808 | page = alloc_pages_node(node, flags, get_order(size)); |
f619cfe1 | 3809 | if (page) |
e4f7c0b4 CM |
3810 | ptr = page_address(page); |
3811 | ||
0116523c | 3812 | return kmalloc_large_node_hook(ptr, size, flags); |
f619cfe1 CL |
3813 | } |
3814 | ||
81819f0f CL |
3815 | void *__kmalloc_node(size_t size, gfp_t flags, int node) |
3816 | { | |
aadb4bc4 | 3817 | struct kmem_cache *s; |
5b882be4 | 3818 | void *ret; |
81819f0f | 3819 | |
95a05b42 | 3820 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { |
5b882be4 EGM |
3821 | ret = kmalloc_large_node(size, flags, node); |
3822 | ||
ca2b84cb EGM |
3823 | trace_kmalloc_node(_RET_IP_, ret, |
3824 | size, PAGE_SIZE << get_order(size), | |
3825 | flags, node); | |
5b882be4 EGM |
3826 | |
3827 | return ret; | |
3828 | } | |
aadb4bc4 | 3829 | |
2c59dd65 | 3830 | s = kmalloc_slab(size, flags); |
aadb4bc4 CL |
3831 | |
3832 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
3833 | return s; |
3834 | ||
2b847c3c | 3835 | ret = slab_alloc_node(s, flags, node, _RET_IP_); |
5b882be4 | 3836 | |
ca2b84cb | 3837 | trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node); |
5b882be4 | 3838 | |
0116523c | 3839 | ret = kasan_kmalloc(s, ret, size, flags); |
0316bec2 | 3840 | |
5b882be4 | 3841 | return ret; |
81819f0f CL |
3842 | } |
3843 | EXPORT_SYMBOL(__kmalloc_node); | |
3844 | #endif | |
3845 | ||
ed18adc1 KC |
3846 | #ifdef CONFIG_HARDENED_USERCOPY |
3847 | /* | |
afcc90f8 KC |
3848 | * Rejects incorrectly sized objects and objects that are to be copied |
3849 | * to/from userspace but do not fall entirely within the containing slab | |
3850 | * cache's usercopy region. | |
ed18adc1 KC |
3851 | * |
3852 | * Returns NULL if check passes, otherwise const char * to name of cache | |
3853 | * to indicate an error. | |
3854 | */ | |
f4e6e289 KC |
3855 | void __check_heap_object(const void *ptr, unsigned long n, struct page *page, |
3856 | bool to_user) | |
ed18adc1 KC |
3857 | { |
3858 | struct kmem_cache *s; | |
44065b2e | 3859 | unsigned int offset; |
ed18adc1 KC |
3860 | size_t object_size; |
3861 | ||
96fedce2 AK |
3862 | ptr = kasan_reset_tag(ptr); |
3863 | ||
ed18adc1 KC |
3864 | /* Find object and usable object size. */ |
3865 | s = page->slab_cache; | |
ed18adc1 KC |
3866 | |
3867 | /* Reject impossible pointers. */ | |
3868 | if (ptr < page_address(page)) | |
f4e6e289 KC |
3869 | usercopy_abort("SLUB object not in SLUB page?!", NULL, |
3870 | to_user, 0, n); | |
ed18adc1 KC |
3871 | |
3872 | /* Find offset within object. */ | |
3873 | offset = (ptr - page_address(page)) % s->size; | |
3874 | ||
3875 | /* Adjust for redzone and reject if within the redzone. */ | |
3876 | if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) { | |
3877 | if (offset < s->red_left_pad) | |
f4e6e289 KC |
3878 | usercopy_abort("SLUB object in left red zone", |
3879 | s->name, to_user, offset, n); | |
ed18adc1 KC |
3880 | offset -= s->red_left_pad; |
3881 | } | |
3882 | ||
afcc90f8 KC |
3883 | /* Allow address range falling entirely within usercopy region. */ |
3884 | if (offset >= s->useroffset && | |
3885 | offset - s->useroffset <= s->usersize && | |
3886 | n <= s->useroffset - offset + s->usersize) | |
f4e6e289 | 3887 | return; |
ed18adc1 | 3888 | |
afcc90f8 KC |
3889 | /* |
3890 | * If the copy is still within the allocated object, produce | |
3891 | * a warning instead of rejecting the copy. This is intended | |
3892 | * to be a temporary method to find any missing usercopy | |
3893 | * whitelists. | |
3894 | */ | |
3895 | object_size = slab_ksize(s); | |
2d891fbc KC |
3896 | if (usercopy_fallback && |
3897 | offset <= object_size && n <= object_size - offset) { | |
afcc90f8 KC |
3898 | usercopy_warn("SLUB object", s->name, to_user, offset, n); |
3899 | return; | |
3900 | } | |
ed18adc1 | 3901 | |
f4e6e289 | 3902 | usercopy_abort("SLUB object", s->name, to_user, offset, n); |
ed18adc1 KC |
3903 | } |
3904 | #endif /* CONFIG_HARDENED_USERCOPY */ | |
3905 | ||
0316bec2 | 3906 | static size_t __ksize(const void *object) |
81819f0f | 3907 | { |
272c1d21 | 3908 | struct page *page; |
81819f0f | 3909 | |
ef8b4520 | 3910 | if (unlikely(object == ZERO_SIZE_PTR)) |
272c1d21 CL |
3911 | return 0; |
3912 | ||
294a80a8 | 3913 | page = virt_to_head_page(object); |
294a80a8 | 3914 | |
76994412 PE |
3915 | if (unlikely(!PageSlab(page))) { |
3916 | WARN_ON(!PageCompound(page)); | |
294a80a8 | 3917 | return PAGE_SIZE << compound_order(page); |
76994412 | 3918 | } |
81819f0f | 3919 | |
1b4f59e3 | 3920 | return slab_ksize(page->slab_cache); |
81819f0f | 3921 | } |
0316bec2 AR |
3922 | |
3923 | size_t ksize(const void *object) | |
3924 | { | |
3925 | size_t size = __ksize(object); | |
3926 | /* We assume that ksize callers could use whole allocated area, | |
4ebb31a4 AP |
3927 | * so we need to unpoison this area. |
3928 | */ | |
3929 | kasan_unpoison_shadow(object, size); | |
0316bec2 AR |
3930 | return size; |
3931 | } | |
b1aabecd | 3932 | EXPORT_SYMBOL(ksize); |
81819f0f CL |
3933 | |
3934 | void kfree(const void *x) | |
3935 | { | |
81819f0f | 3936 | struct page *page; |
5bb983b0 | 3937 | void *object = (void *)x; |
81819f0f | 3938 | |
2121db74 PE |
3939 | trace_kfree(_RET_IP_, x); |
3940 | ||
2408c550 | 3941 | if (unlikely(ZERO_OR_NULL_PTR(x))) |
81819f0f CL |
3942 | return; |
3943 | ||
b49af68f | 3944 | page = virt_to_head_page(x); |
aadb4bc4 | 3945 | if (unlikely(!PageSlab(page))) { |
0937502a | 3946 | BUG_ON(!PageCompound(page)); |
47adccce | 3947 | kfree_hook(object); |
4949148a | 3948 | __free_pages(page, compound_order(page)); |
aadb4bc4 CL |
3949 | return; |
3950 | } | |
81084651 | 3951 | slab_free(page->slab_cache, page, object, NULL, 1, _RET_IP_); |
81819f0f CL |
3952 | } |
3953 | EXPORT_SYMBOL(kfree); | |
3954 | ||
832f37f5 VD |
3955 | #define SHRINK_PROMOTE_MAX 32 |
3956 | ||
2086d26a | 3957 | /* |
832f37f5 VD |
3958 | * kmem_cache_shrink discards empty slabs and promotes the slabs filled |
3959 | * up most to the head of the partial lists. New allocations will then | |
3960 | * fill those up and thus they can be removed from the partial lists. | |
672bba3a CL |
3961 | * |
3962 | * The slabs with the least items are placed last. This results in them | |
3963 | * being allocated from last increasing the chance that the last objects | |
3964 | * are freed in them. | |
2086d26a | 3965 | */ |
c9fc5864 | 3966 | int __kmem_cache_shrink(struct kmem_cache *s) |
2086d26a CL |
3967 | { |
3968 | int node; | |
3969 | int i; | |
3970 | struct kmem_cache_node *n; | |
3971 | struct page *page; | |
3972 | struct page *t; | |
832f37f5 VD |
3973 | struct list_head discard; |
3974 | struct list_head promote[SHRINK_PROMOTE_MAX]; | |
2086d26a | 3975 | unsigned long flags; |
ce3712d7 | 3976 | int ret = 0; |
2086d26a | 3977 | |
2086d26a | 3978 | flush_all(s); |
fa45dc25 | 3979 | for_each_kmem_cache_node(s, node, n) { |
832f37f5 VD |
3980 | INIT_LIST_HEAD(&discard); |
3981 | for (i = 0; i < SHRINK_PROMOTE_MAX; i++) | |
3982 | INIT_LIST_HEAD(promote + i); | |
2086d26a CL |
3983 | |
3984 | spin_lock_irqsave(&n->list_lock, flags); | |
3985 | ||
3986 | /* | |
832f37f5 | 3987 | * Build lists of slabs to discard or promote. |
2086d26a | 3988 | * |
672bba3a CL |
3989 | * Note that concurrent frees may occur while we hold the |
3990 | * list_lock. page->inuse here is the upper limit. | |
2086d26a CL |
3991 | */ |
3992 | list_for_each_entry_safe(page, t, &n->partial, lru) { | |
832f37f5 VD |
3993 | int free = page->objects - page->inuse; |
3994 | ||
3995 | /* Do not reread page->inuse */ | |
3996 | barrier(); | |
3997 | ||
3998 | /* We do not keep full slabs on the list */ | |
3999 | BUG_ON(free <= 0); | |
4000 | ||
4001 | if (free == page->objects) { | |
4002 | list_move(&page->lru, &discard); | |
69cb8e6b | 4003 | n->nr_partial--; |
832f37f5 VD |
4004 | } else if (free <= SHRINK_PROMOTE_MAX) |
4005 | list_move(&page->lru, promote + free - 1); | |
2086d26a CL |
4006 | } |
4007 | ||
2086d26a | 4008 | /* |
832f37f5 VD |
4009 | * Promote the slabs filled up most to the head of the |
4010 | * partial list. | |
2086d26a | 4011 | */ |
832f37f5 VD |
4012 | for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--) |
4013 | list_splice(promote + i, &n->partial); | |
2086d26a | 4014 | |
2086d26a | 4015 | spin_unlock_irqrestore(&n->list_lock, flags); |
69cb8e6b CL |
4016 | |
4017 | /* Release empty slabs */ | |
832f37f5 | 4018 | list_for_each_entry_safe(page, t, &discard, lru) |
69cb8e6b | 4019 | discard_slab(s, page); |
ce3712d7 VD |
4020 | |
4021 | if (slabs_node(s, node)) | |
4022 | ret = 1; | |
2086d26a CL |
4023 | } |
4024 | ||
ce3712d7 | 4025 | return ret; |
2086d26a | 4026 | } |
2086d26a | 4027 | |
c9fc5864 | 4028 | #ifdef CONFIG_MEMCG |
01fb58bc TH |
4029 | static void kmemcg_cache_deact_after_rcu(struct kmem_cache *s) |
4030 | { | |
50862ce7 TH |
4031 | /* |
4032 | * Called with all the locks held after a sched RCU grace period. | |
4033 | * Even if @s becomes empty after shrinking, we can't know that @s | |
4034 | * doesn't have allocations already in-flight and thus can't | |
4035 | * destroy @s until the associated memcg is released. | |
4036 | * | |
4037 | * However, let's remove the sysfs files for empty caches here. | |
4038 | * Each cache has a lot of interface files which aren't | |
4039 | * particularly useful for empty draining caches; otherwise, we can | |
4040 | * easily end up with millions of unnecessary sysfs files on | |
4041 | * systems which have a lot of memory and transient cgroups. | |
4042 | */ | |
4043 | if (!__kmem_cache_shrink(s)) | |
4044 | sysfs_slab_remove(s); | |
01fb58bc TH |
4045 | } |
4046 | ||
c9fc5864 TH |
4047 | void __kmemcg_cache_deactivate(struct kmem_cache *s) |
4048 | { | |
4049 | /* | |
4050 | * Disable empty slabs caching. Used to avoid pinning offline | |
4051 | * memory cgroups by kmem pages that can be freed. | |
4052 | */ | |
e6d0e1dc | 4053 | slub_set_cpu_partial(s, 0); |
c9fc5864 TH |
4054 | s->min_partial = 0; |
4055 | ||
4056 | /* | |
4057 | * s->cpu_partial is checked locklessly (see put_cpu_partial), so | |
01fb58bc | 4058 | * we have to make sure the change is visible before shrinking. |
c9fc5864 | 4059 | */ |
01fb58bc | 4060 | slab_deactivate_memcg_cache_rcu_sched(s, kmemcg_cache_deact_after_rcu); |
c9fc5864 TH |
4061 | } |
4062 | #endif | |
4063 | ||
b9049e23 YG |
4064 | static int slab_mem_going_offline_callback(void *arg) |
4065 | { | |
4066 | struct kmem_cache *s; | |
4067 | ||
18004c5d | 4068 | mutex_lock(&slab_mutex); |
b9049e23 | 4069 | list_for_each_entry(s, &slab_caches, list) |
c9fc5864 | 4070 | __kmem_cache_shrink(s); |
18004c5d | 4071 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
4072 | |
4073 | return 0; | |
4074 | } | |
4075 | ||
4076 | static void slab_mem_offline_callback(void *arg) | |
4077 | { | |
4078 | struct kmem_cache_node *n; | |
4079 | struct kmem_cache *s; | |
4080 | struct memory_notify *marg = arg; | |
4081 | int offline_node; | |
4082 | ||
b9d5ab25 | 4083 | offline_node = marg->status_change_nid_normal; |
b9049e23 YG |
4084 | |
4085 | /* | |
4086 | * If the node still has available memory. we need kmem_cache_node | |
4087 | * for it yet. | |
4088 | */ | |
4089 | if (offline_node < 0) | |
4090 | return; | |
4091 | ||
18004c5d | 4092 | mutex_lock(&slab_mutex); |
b9049e23 YG |
4093 | list_for_each_entry(s, &slab_caches, list) { |
4094 | n = get_node(s, offline_node); | |
4095 | if (n) { | |
4096 | /* | |
4097 | * if n->nr_slabs > 0, slabs still exist on the node | |
4098 | * that is going down. We were unable to free them, | |
c9404c9c | 4099 | * and offline_pages() function shouldn't call this |
b9049e23 YG |
4100 | * callback. So, we must fail. |
4101 | */ | |
0f389ec6 | 4102 | BUG_ON(slabs_node(s, offline_node)); |
b9049e23 YG |
4103 | |
4104 | s->node[offline_node] = NULL; | |
8de66a0c | 4105 | kmem_cache_free(kmem_cache_node, n); |
b9049e23 YG |
4106 | } |
4107 | } | |
18004c5d | 4108 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
4109 | } |
4110 | ||
4111 | static int slab_mem_going_online_callback(void *arg) | |
4112 | { | |
4113 | struct kmem_cache_node *n; | |
4114 | struct kmem_cache *s; | |
4115 | struct memory_notify *marg = arg; | |
b9d5ab25 | 4116 | int nid = marg->status_change_nid_normal; |
b9049e23 YG |
4117 | int ret = 0; |
4118 | ||
4119 | /* | |
4120 | * If the node's memory is already available, then kmem_cache_node is | |
4121 | * already created. Nothing to do. | |
4122 | */ | |
4123 | if (nid < 0) | |
4124 | return 0; | |
4125 | ||
4126 | /* | |
0121c619 | 4127 | * We are bringing a node online. No memory is available yet. We must |
b9049e23 YG |
4128 | * allocate a kmem_cache_node structure in order to bring the node |
4129 | * online. | |
4130 | */ | |
18004c5d | 4131 | mutex_lock(&slab_mutex); |
b9049e23 YG |
4132 | list_for_each_entry(s, &slab_caches, list) { |
4133 | /* | |
4134 | * XXX: kmem_cache_alloc_node will fallback to other nodes | |
4135 | * since memory is not yet available from the node that | |
4136 | * is brought up. | |
4137 | */ | |
8de66a0c | 4138 | n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL); |
b9049e23 YG |
4139 | if (!n) { |
4140 | ret = -ENOMEM; | |
4141 | goto out; | |
4142 | } | |
4053497d | 4143 | init_kmem_cache_node(n); |
b9049e23 YG |
4144 | s->node[nid] = n; |
4145 | } | |
4146 | out: | |
18004c5d | 4147 | mutex_unlock(&slab_mutex); |
b9049e23 YG |
4148 | return ret; |
4149 | } | |
4150 | ||
4151 | static int slab_memory_callback(struct notifier_block *self, | |
4152 | unsigned long action, void *arg) | |
4153 | { | |
4154 | int ret = 0; | |
4155 | ||
4156 | switch (action) { | |
4157 | case MEM_GOING_ONLINE: | |
4158 | ret = slab_mem_going_online_callback(arg); | |
4159 | break; | |
4160 | case MEM_GOING_OFFLINE: | |
4161 | ret = slab_mem_going_offline_callback(arg); | |
4162 | break; | |
4163 | case MEM_OFFLINE: | |
4164 | case MEM_CANCEL_ONLINE: | |
4165 | slab_mem_offline_callback(arg); | |
4166 | break; | |
4167 | case MEM_ONLINE: | |
4168 | case MEM_CANCEL_OFFLINE: | |
4169 | break; | |
4170 | } | |
dc19f9db KH |
4171 | if (ret) |
4172 | ret = notifier_from_errno(ret); | |
4173 | else | |
4174 | ret = NOTIFY_OK; | |
b9049e23 YG |
4175 | return ret; |
4176 | } | |
4177 | ||
3ac38faa AM |
4178 | static struct notifier_block slab_memory_callback_nb = { |
4179 | .notifier_call = slab_memory_callback, | |
4180 | .priority = SLAB_CALLBACK_PRI, | |
4181 | }; | |
b9049e23 | 4182 | |
81819f0f CL |
4183 | /******************************************************************** |
4184 | * Basic setup of slabs | |
4185 | *******************************************************************/ | |
4186 | ||
51df1142 CL |
4187 | /* |
4188 | * Used for early kmem_cache structures that were allocated using | |
dffb4d60 CL |
4189 | * the page allocator. Allocate them properly then fix up the pointers |
4190 | * that may be pointing to the wrong kmem_cache structure. | |
51df1142 CL |
4191 | */ |
4192 | ||
dffb4d60 | 4193 | static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache) |
51df1142 CL |
4194 | { |
4195 | int node; | |
dffb4d60 | 4196 | struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); |
fa45dc25 | 4197 | struct kmem_cache_node *n; |
51df1142 | 4198 | |
dffb4d60 | 4199 | memcpy(s, static_cache, kmem_cache->object_size); |
51df1142 | 4200 | |
7d557b3c GC |
4201 | /* |
4202 | * This runs very early, and only the boot processor is supposed to be | |
4203 | * up. Even if it weren't true, IRQs are not up so we couldn't fire | |
4204 | * IPIs around. | |
4205 | */ | |
4206 | __flush_cpu_slab(s, smp_processor_id()); | |
fa45dc25 | 4207 | for_each_kmem_cache_node(s, node, n) { |
51df1142 CL |
4208 | struct page *p; |
4209 | ||
fa45dc25 CL |
4210 | list_for_each_entry(p, &n->partial, lru) |
4211 | p->slab_cache = s; | |
51df1142 | 4212 | |
607bf324 | 4213 | #ifdef CONFIG_SLUB_DEBUG |
fa45dc25 CL |
4214 | list_for_each_entry(p, &n->full, lru) |
4215 | p->slab_cache = s; | |
51df1142 | 4216 | #endif |
51df1142 | 4217 | } |
f7ce3190 | 4218 | slab_init_memcg_params(s); |
dffb4d60 | 4219 | list_add(&s->list, &slab_caches); |
510ded33 | 4220 | memcg_link_cache(s); |
dffb4d60 | 4221 | return s; |
51df1142 CL |
4222 | } |
4223 | ||
81819f0f CL |
4224 | void __init kmem_cache_init(void) |
4225 | { | |
dffb4d60 CL |
4226 | static __initdata struct kmem_cache boot_kmem_cache, |
4227 | boot_kmem_cache_node; | |
51df1142 | 4228 | |
fc8d8620 SG |
4229 | if (debug_guardpage_minorder()) |
4230 | slub_max_order = 0; | |
4231 | ||
dffb4d60 CL |
4232 | kmem_cache_node = &boot_kmem_cache_node; |
4233 | kmem_cache = &boot_kmem_cache; | |
51df1142 | 4234 | |
dffb4d60 | 4235 | create_boot_cache(kmem_cache_node, "kmem_cache_node", |
8eb8284b | 4236 | sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0); |
b9049e23 | 4237 | |
3ac38faa | 4238 | register_hotmemory_notifier(&slab_memory_callback_nb); |
81819f0f CL |
4239 | |
4240 | /* Able to allocate the per node structures */ | |
4241 | slab_state = PARTIAL; | |
4242 | ||
dffb4d60 CL |
4243 | create_boot_cache(kmem_cache, "kmem_cache", |
4244 | offsetof(struct kmem_cache, node) + | |
4245 | nr_node_ids * sizeof(struct kmem_cache_node *), | |
8eb8284b | 4246 | SLAB_HWCACHE_ALIGN, 0, 0); |
8a13a4cc | 4247 | |
dffb4d60 | 4248 | kmem_cache = bootstrap(&boot_kmem_cache); |
dffb4d60 | 4249 | kmem_cache_node = bootstrap(&boot_kmem_cache_node); |
51df1142 CL |
4250 | |
4251 | /* Now we can use the kmem_cache to allocate kmalloc slabs */ | |
34cc6990 | 4252 | setup_kmalloc_cache_index_table(); |
f97d5f63 | 4253 | create_kmalloc_caches(0); |
81819f0f | 4254 | |
210e7a43 TG |
4255 | /* Setup random freelists for each cache */ |
4256 | init_freelist_randomization(); | |
4257 | ||
a96a87bf SAS |
4258 | cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL, |
4259 | slub_cpu_dead); | |
81819f0f | 4260 | |
19af27af | 4261 | pr_info("SLUB: HWalign=%d, Order=%u-%u, MinObjects=%u, CPUs=%u, Nodes=%d\n", |
f97d5f63 | 4262 | cache_line_size(), |
81819f0f CL |
4263 | slub_min_order, slub_max_order, slub_min_objects, |
4264 | nr_cpu_ids, nr_node_ids); | |
4265 | } | |
4266 | ||
7e85ee0c PE |
4267 | void __init kmem_cache_init_late(void) |
4268 | { | |
7e85ee0c PE |
4269 | } |
4270 | ||
2633d7a0 | 4271 | struct kmem_cache * |
f4957d5b | 4272 | __kmem_cache_alias(const char *name, unsigned int size, unsigned int align, |
d50112ed | 4273 | slab_flags_t flags, void (*ctor)(void *)) |
81819f0f | 4274 | { |
426589f5 | 4275 | struct kmem_cache *s, *c; |
81819f0f | 4276 | |
a44cb944 | 4277 | s = find_mergeable(size, align, flags, name, ctor); |
81819f0f CL |
4278 | if (s) { |
4279 | s->refcount++; | |
84d0ddd6 | 4280 | |
81819f0f CL |
4281 | /* |
4282 | * Adjust the object sizes so that we clear | |
4283 | * the complete object on kzalloc. | |
4284 | */ | |
1b473f29 | 4285 | s->object_size = max(s->object_size, size); |
52ee6d74 | 4286 | s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); |
6446faa2 | 4287 | |
426589f5 | 4288 | for_each_memcg_cache(c, s) { |
84d0ddd6 | 4289 | c->object_size = s->object_size; |
52ee6d74 | 4290 | c->inuse = max(c->inuse, ALIGN(size, sizeof(void *))); |
84d0ddd6 VD |
4291 | } |
4292 | ||
7b8f3b66 | 4293 | if (sysfs_slab_alias(s, name)) { |
7b8f3b66 | 4294 | s->refcount--; |
cbb79694 | 4295 | s = NULL; |
7b8f3b66 | 4296 | } |
a0e1d1be | 4297 | } |
6446faa2 | 4298 | |
cbb79694 CL |
4299 | return s; |
4300 | } | |
84c1cf62 | 4301 | |
d50112ed | 4302 | int __kmem_cache_create(struct kmem_cache *s, slab_flags_t flags) |
cbb79694 | 4303 | { |
aac3a166 PE |
4304 | int err; |
4305 | ||
4306 | err = kmem_cache_open(s, flags); | |
4307 | if (err) | |
4308 | return err; | |
20cea968 | 4309 | |
45530c44 CL |
4310 | /* Mutex is not taken during early boot */ |
4311 | if (slab_state <= UP) | |
4312 | return 0; | |
4313 | ||
107dab5c | 4314 | memcg_propagate_slab_attrs(s); |
aac3a166 | 4315 | err = sysfs_slab_add(s); |
aac3a166 | 4316 | if (err) |
52b4b950 | 4317 | __kmem_cache_release(s); |
20cea968 | 4318 | |
aac3a166 | 4319 | return err; |
81819f0f | 4320 | } |
81819f0f | 4321 | |
ce71e27c | 4322 | void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller) |
81819f0f | 4323 | { |
aadb4bc4 | 4324 | struct kmem_cache *s; |
94b528d0 | 4325 | void *ret; |
aadb4bc4 | 4326 | |
95a05b42 | 4327 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) |
eada35ef PE |
4328 | return kmalloc_large(size, gfpflags); |
4329 | ||
2c59dd65 | 4330 | s = kmalloc_slab(size, gfpflags); |
81819f0f | 4331 | |
2408c550 | 4332 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 4333 | return s; |
81819f0f | 4334 | |
2b847c3c | 4335 | ret = slab_alloc(s, gfpflags, caller); |
94b528d0 | 4336 | |
25985edc | 4337 | /* Honor the call site pointer we received. */ |
ca2b84cb | 4338 | trace_kmalloc(caller, ret, size, s->size, gfpflags); |
94b528d0 EGM |
4339 | |
4340 | return ret; | |
81819f0f CL |
4341 | } |
4342 | ||
5d1f57e4 | 4343 | #ifdef CONFIG_NUMA |
81819f0f | 4344 | void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, |
ce71e27c | 4345 | int node, unsigned long caller) |
81819f0f | 4346 | { |
aadb4bc4 | 4347 | struct kmem_cache *s; |
94b528d0 | 4348 | void *ret; |
aadb4bc4 | 4349 | |
95a05b42 | 4350 | if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) { |
d3e14aa3 XF |
4351 | ret = kmalloc_large_node(size, gfpflags, node); |
4352 | ||
4353 | trace_kmalloc_node(caller, ret, | |
4354 | size, PAGE_SIZE << get_order(size), | |
4355 | gfpflags, node); | |
4356 | ||
4357 | return ret; | |
4358 | } | |
eada35ef | 4359 | |
2c59dd65 | 4360 | s = kmalloc_slab(size, gfpflags); |
81819f0f | 4361 | |
2408c550 | 4362 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 4363 | return s; |
81819f0f | 4364 | |
2b847c3c | 4365 | ret = slab_alloc_node(s, gfpflags, node, caller); |
94b528d0 | 4366 | |
25985edc | 4367 | /* Honor the call site pointer we received. */ |
ca2b84cb | 4368 | trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node); |
94b528d0 EGM |
4369 | |
4370 | return ret; | |
81819f0f | 4371 | } |
5d1f57e4 | 4372 | #endif |
81819f0f | 4373 | |
ab4d5ed5 | 4374 | #ifdef CONFIG_SYSFS |
205ab99d CL |
4375 | static int count_inuse(struct page *page) |
4376 | { | |
4377 | return page->inuse; | |
4378 | } | |
4379 | ||
4380 | static int count_total(struct page *page) | |
4381 | { | |
4382 | return page->objects; | |
4383 | } | |
ab4d5ed5 | 4384 | #endif |
205ab99d | 4385 | |
ab4d5ed5 | 4386 | #ifdef CONFIG_SLUB_DEBUG |
434e245d CL |
4387 | static int validate_slab(struct kmem_cache *s, struct page *page, |
4388 | unsigned long *map) | |
53e15af0 CL |
4389 | { |
4390 | void *p; | |
a973e9dd | 4391 | void *addr = page_address(page); |
53e15af0 CL |
4392 | |
4393 | if (!check_slab(s, page) || | |
4394 | !on_freelist(s, page, NULL)) | |
4395 | return 0; | |
4396 | ||
4397 | /* Now we know that a valid freelist exists */ | |
39b26464 | 4398 | bitmap_zero(map, page->objects); |
53e15af0 | 4399 | |
5f80b13a CL |
4400 | get_map(s, page, map); |
4401 | for_each_object(p, s, addr, page->objects) { | |
4402 | if (test_bit(slab_index(p, s, addr), map)) | |
4403 | if (!check_object(s, page, p, SLUB_RED_INACTIVE)) | |
4404 | return 0; | |
53e15af0 CL |
4405 | } |
4406 | ||
224a88be | 4407 | for_each_object(p, s, addr, page->objects) |
7656c72b | 4408 | if (!test_bit(slab_index(p, s, addr), map)) |
37d57443 | 4409 | if (!check_object(s, page, p, SLUB_RED_ACTIVE)) |
53e15af0 CL |
4410 | return 0; |
4411 | return 1; | |
4412 | } | |
4413 | ||
434e245d CL |
4414 | static void validate_slab_slab(struct kmem_cache *s, struct page *page, |
4415 | unsigned long *map) | |
53e15af0 | 4416 | { |
881db7fb CL |
4417 | slab_lock(page); |
4418 | validate_slab(s, page, map); | |
4419 | slab_unlock(page); | |
53e15af0 CL |
4420 | } |
4421 | ||
434e245d CL |
4422 | static int validate_slab_node(struct kmem_cache *s, |
4423 | struct kmem_cache_node *n, unsigned long *map) | |
53e15af0 CL |
4424 | { |
4425 | unsigned long count = 0; | |
4426 | struct page *page; | |
4427 | unsigned long flags; | |
4428 | ||
4429 | spin_lock_irqsave(&n->list_lock, flags); | |
4430 | ||
4431 | list_for_each_entry(page, &n->partial, lru) { | |
434e245d | 4432 | validate_slab_slab(s, page, map); |
53e15af0 CL |
4433 | count++; |
4434 | } | |
4435 | if (count != n->nr_partial) | |
f9f58285 FF |
4436 | pr_err("SLUB %s: %ld partial slabs counted but counter=%ld\n", |
4437 | s->name, count, n->nr_partial); | |
53e15af0 CL |
4438 | |
4439 | if (!(s->flags & SLAB_STORE_USER)) | |
4440 | goto out; | |
4441 | ||
4442 | list_for_each_entry(page, &n->full, lru) { | |
434e245d | 4443 | validate_slab_slab(s, page, map); |
53e15af0 CL |
4444 | count++; |
4445 | } | |
4446 | if (count != atomic_long_read(&n->nr_slabs)) | |
f9f58285 FF |
4447 | pr_err("SLUB: %s %ld slabs counted but counter=%ld\n", |
4448 | s->name, count, atomic_long_read(&n->nr_slabs)); | |
53e15af0 CL |
4449 | |
4450 | out: | |
4451 | spin_unlock_irqrestore(&n->list_lock, flags); | |
4452 | return count; | |
4453 | } | |
4454 | ||
434e245d | 4455 | static long validate_slab_cache(struct kmem_cache *s) |
53e15af0 CL |
4456 | { |
4457 | int node; | |
4458 | unsigned long count = 0; | |
fa45dc25 | 4459 | struct kmem_cache_node *n; |
0684e652 | 4460 | unsigned long *map = bitmap_alloc(oo_objects(s->max), GFP_KERNEL); |
434e245d CL |
4461 | |
4462 | if (!map) | |
4463 | return -ENOMEM; | |
53e15af0 CL |
4464 | |
4465 | flush_all(s); | |
fa45dc25 | 4466 | for_each_kmem_cache_node(s, node, n) |
434e245d | 4467 | count += validate_slab_node(s, n, map); |
0684e652 | 4468 | bitmap_free(map); |
53e15af0 CL |
4469 | return count; |
4470 | } | |
88a420e4 | 4471 | /* |
672bba3a | 4472 | * Generate lists of code addresses where slabcache objects are allocated |
88a420e4 CL |
4473 | * and freed. |
4474 | */ | |
4475 | ||
4476 | struct location { | |
4477 | unsigned long count; | |
ce71e27c | 4478 | unsigned long addr; |
45edfa58 CL |
4479 | long long sum_time; |
4480 | long min_time; | |
4481 | long max_time; | |
4482 | long min_pid; | |
4483 | long max_pid; | |
174596a0 | 4484 | DECLARE_BITMAP(cpus, NR_CPUS); |
45edfa58 | 4485 | nodemask_t nodes; |
88a420e4 CL |
4486 | }; |
4487 | ||
4488 | struct loc_track { | |
4489 | unsigned long max; | |
4490 | unsigned long count; | |
4491 | struct location *loc; | |
4492 | }; | |
4493 | ||
4494 | static void free_loc_track(struct loc_track *t) | |
4495 | { | |
4496 | if (t->max) | |
4497 | free_pages((unsigned long)t->loc, | |
4498 | get_order(sizeof(struct location) * t->max)); | |
4499 | } | |
4500 | ||
68dff6a9 | 4501 | static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) |
88a420e4 CL |
4502 | { |
4503 | struct location *l; | |
4504 | int order; | |
4505 | ||
88a420e4 CL |
4506 | order = get_order(sizeof(struct location) * max); |
4507 | ||
68dff6a9 | 4508 | l = (void *)__get_free_pages(flags, order); |
88a420e4 CL |
4509 | if (!l) |
4510 | return 0; | |
4511 | ||
4512 | if (t->count) { | |
4513 | memcpy(l, t->loc, sizeof(struct location) * t->count); | |
4514 | free_loc_track(t); | |
4515 | } | |
4516 | t->max = max; | |
4517 | t->loc = l; | |
4518 | return 1; | |
4519 | } | |
4520 | ||
4521 | static int add_location(struct loc_track *t, struct kmem_cache *s, | |
45edfa58 | 4522 | const struct track *track) |
88a420e4 CL |
4523 | { |
4524 | long start, end, pos; | |
4525 | struct location *l; | |
ce71e27c | 4526 | unsigned long caddr; |
45edfa58 | 4527 | unsigned long age = jiffies - track->when; |
88a420e4 CL |
4528 | |
4529 | start = -1; | |
4530 | end = t->count; | |
4531 | ||
4532 | for ( ; ; ) { | |
4533 | pos = start + (end - start + 1) / 2; | |
4534 | ||
4535 | /* | |
4536 | * There is nothing at "end". If we end up there | |
4537 | * we need to add something to before end. | |
4538 | */ | |
4539 | if (pos == end) | |
4540 | break; | |
4541 | ||
4542 | caddr = t->loc[pos].addr; | |
45edfa58 CL |
4543 | if (track->addr == caddr) { |
4544 | ||
4545 | l = &t->loc[pos]; | |
4546 | l->count++; | |
4547 | if (track->when) { | |
4548 | l->sum_time += age; | |
4549 | if (age < l->min_time) | |
4550 | l->min_time = age; | |
4551 | if (age > l->max_time) | |
4552 | l->max_time = age; | |
4553 | ||
4554 | if (track->pid < l->min_pid) | |
4555 | l->min_pid = track->pid; | |
4556 | if (track->pid > l->max_pid) | |
4557 | l->max_pid = track->pid; | |
4558 | ||
174596a0 RR |
4559 | cpumask_set_cpu(track->cpu, |
4560 | to_cpumask(l->cpus)); | |
45edfa58 CL |
4561 | } |
4562 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
4563 | return 1; |
4564 | } | |
4565 | ||
45edfa58 | 4566 | if (track->addr < caddr) |
88a420e4 CL |
4567 | end = pos; |
4568 | else | |
4569 | start = pos; | |
4570 | } | |
4571 | ||
4572 | /* | |
672bba3a | 4573 | * Not found. Insert new tracking element. |
88a420e4 | 4574 | */ |
68dff6a9 | 4575 | if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) |
88a420e4 CL |
4576 | return 0; |
4577 | ||
4578 | l = t->loc + pos; | |
4579 | if (pos < t->count) | |
4580 | memmove(l + 1, l, | |
4581 | (t->count - pos) * sizeof(struct location)); | |
4582 | t->count++; | |
4583 | l->count = 1; | |
45edfa58 CL |
4584 | l->addr = track->addr; |
4585 | l->sum_time = age; | |
4586 | l->min_time = age; | |
4587 | l->max_time = age; | |
4588 | l->min_pid = track->pid; | |
4589 | l->max_pid = track->pid; | |
174596a0 RR |
4590 | cpumask_clear(to_cpumask(l->cpus)); |
4591 | cpumask_set_cpu(track->cpu, to_cpumask(l->cpus)); | |
45edfa58 CL |
4592 | nodes_clear(l->nodes); |
4593 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
4594 | return 1; |
4595 | } | |
4596 | ||
4597 | static void process_slab(struct loc_track *t, struct kmem_cache *s, | |
bbd7d57b | 4598 | struct page *page, enum track_item alloc, |
a5dd5c11 | 4599 | unsigned long *map) |
88a420e4 | 4600 | { |
a973e9dd | 4601 | void *addr = page_address(page); |
88a420e4 CL |
4602 | void *p; |
4603 | ||
39b26464 | 4604 | bitmap_zero(map, page->objects); |
5f80b13a | 4605 | get_map(s, page, map); |
88a420e4 | 4606 | |
224a88be | 4607 | for_each_object(p, s, addr, page->objects) |
45edfa58 CL |
4608 | if (!test_bit(slab_index(p, s, addr), map)) |
4609 | add_location(t, s, get_track(s, p, alloc)); | |
88a420e4 CL |
4610 | } |
4611 | ||
4612 | static int list_locations(struct kmem_cache *s, char *buf, | |
4613 | enum track_item alloc) | |
4614 | { | |
e374d483 | 4615 | int len = 0; |
88a420e4 | 4616 | unsigned long i; |
68dff6a9 | 4617 | struct loc_track t = { 0, 0, NULL }; |
88a420e4 | 4618 | int node; |
fa45dc25 | 4619 | struct kmem_cache_node *n; |
0684e652 | 4620 | unsigned long *map = bitmap_alloc(oo_objects(s->max), GFP_KERNEL); |
88a420e4 | 4621 | |
bbd7d57b | 4622 | if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location), |
0ee931c4 | 4623 | GFP_KERNEL)) { |
0684e652 | 4624 | bitmap_free(map); |
68dff6a9 | 4625 | return sprintf(buf, "Out of memory\n"); |
bbd7d57b | 4626 | } |
88a420e4 CL |
4627 | /* Push back cpu slabs */ |
4628 | flush_all(s); | |
4629 | ||
fa45dc25 | 4630 | for_each_kmem_cache_node(s, node, n) { |
88a420e4 CL |
4631 | unsigned long flags; |
4632 | struct page *page; | |
4633 | ||
9e86943b | 4634 | if (!atomic_long_read(&n->nr_slabs)) |
88a420e4 CL |
4635 | continue; |
4636 | ||
4637 | spin_lock_irqsave(&n->list_lock, flags); | |
4638 | list_for_each_entry(page, &n->partial, lru) | |
bbd7d57b | 4639 | process_slab(&t, s, page, alloc, map); |
88a420e4 | 4640 | list_for_each_entry(page, &n->full, lru) |
bbd7d57b | 4641 | process_slab(&t, s, page, alloc, map); |
88a420e4 CL |
4642 | spin_unlock_irqrestore(&n->list_lock, flags); |
4643 | } | |
4644 | ||
4645 | for (i = 0; i < t.count; i++) { | |
45edfa58 | 4646 | struct location *l = &t.loc[i]; |
88a420e4 | 4647 | |
9c246247 | 4648 | if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100) |
88a420e4 | 4649 | break; |
e374d483 | 4650 | len += sprintf(buf + len, "%7ld ", l->count); |
45edfa58 CL |
4651 | |
4652 | if (l->addr) | |
62c70bce | 4653 | len += sprintf(buf + len, "%pS", (void *)l->addr); |
88a420e4 | 4654 | else |
e374d483 | 4655 | len += sprintf(buf + len, "<not-available>"); |
45edfa58 CL |
4656 | |
4657 | if (l->sum_time != l->min_time) { | |
e374d483 | 4658 | len += sprintf(buf + len, " age=%ld/%ld/%ld", |
f8bd2258 RZ |
4659 | l->min_time, |
4660 | (long)div_u64(l->sum_time, l->count), | |
4661 | l->max_time); | |
45edfa58 | 4662 | } else |
e374d483 | 4663 | len += sprintf(buf + len, " age=%ld", |
45edfa58 CL |
4664 | l->min_time); |
4665 | ||
4666 | if (l->min_pid != l->max_pid) | |
e374d483 | 4667 | len += sprintf(buf + len, " pid=%ld-%ld", |
45edfa58 CL |
4668 | l->min_pid, l->max_pid); |
4669 | else | |
e374d483 | 4670 | len += sprintf(buf + len, " pid=%ld", |
45edfa58 CL |
4671 | l->min_pid); |
4672 | ||
174596a0 RR |
4673 | if (num_online_cpus() > 1 && |
4674 | !cpumask_empty(to_cpumask(l->cpus)) && | |
5024c1d7 TH |
4675 | len < PAGE_SIZE - 60) |
4676 | len += scnprintf(buf + len, PAGE_SIZE - len - 50, | |
4677 | " cpus=%*pbl", | |
4678 | cpumask_pr_args(to_cpumask(l->cpus))); | |
45edfa58 | 4679 | |
62bc62a8 | 4680 | if (nr_online_nodes > 1 && !nodes_empty(l->nodes) && |
5024c1d7 TH |
4681 | len < PAGE_SIZE - 60) |
4682 | len += scnprintf(buf + len, PAGE_SIZE - len - 50, | |
4683 | " nodes=%*pbl", | |
4684 | nodemask_pr_args(&l->nodes)); | |
45edfa58 | 4685 | |
e374d483 | 4686 | len += sprintf(buf + len, "\n"); |
88a420e4 CL |
4687 | } |
4688 | ||
4689 | free_loc_track(&t); | |
0684e652 | 4690 | bitmap_free(map); |
88a420e4 | 4691 | if (!t.count) |
e374d483 HH |
4692 | len += sprintf(buf, "No data\n"); |
4693 | return len; | |
88a420e4 | 4694 | } |
ab4d5ed5 | 4695 | #endif |
88a420e4 | 4696 | |
a5a84755 | 4697 | #ifdef SLUB_RESILIENCY_TEST |
c07b8183 | 4698 | static void __init resiliency_test(void) |
a5a84755 CL |
4699 | { |
4700 | u8 *p; | |
cc252eae | 4701 | int type = KMALLOC_NORMAL; |
a5a84755 | 4702 | |
95a05b42 | 4703 | BUILD_BUG_ON(KMALLOC_MIN_SIZE > 16 || KMALLOC_SHIFT_HIGH < 10); |
a5a84755 | 4704 | |
f9f58285 FF |
4705 | pr_err("SLUB resiliency testing\n"); |
4706 | pr_err("-----------------------\n"); | |
4707 | pr_err("A. Corruption after allocation\n"); | |
a5a84755 CL |
4708 | |
4709 | p = kzalloc(16, GFP_KERNEL); | |
4710 | p[16] = 0x12; | |
f9f58285 FF |
4711 | pr_err("\n1. kmalloc-16: Clobber Redzone/next pointer 0x12->0x%p\n\n", |
4712 | p + 16); | |
a5a84755 | 4713 | |
cc252eae | 4714 | validate_slab_cache(kmalloc_caches[type][4]); |
a5a84755 CL |
4715 | |
4716 | /* Hmmm... The next two are dangerous */ | |
4717 | p = kzalloc(32, GFP_KERNEL); | |
4718 | p[32 + sizeof(void *)] = 0x34; | |
f9f58285 FF |
4719 | pr_err("\n2. kmalloc-32: Clobber next pointer/next slab 0x34 -> -0x%p\n", |
4720 | p); | |
4721 | pr_err("If allocated object is overwritten then not detectable\n\n"); | |
a5a84755 | 4722 | |
cc252eae | 4723 | validate_slab_cache(kmalloc_caches[type][5]); |
a5a84755 CL |
4724 | p = kzalloc(64, GFP_KERNEL); |
4725 | p += 64 + (get_cycles() & 0xff) * sizeof(void *); | |
4726 | *p = 0x56; | |
f9f58285 FF |
4727 | pr_err("\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n", |
4728 | p); | |
4729 | pr_err("If allocated object is overwritten then not detectable\n\n"); | |
cc252eae | 4730 | validate_slab_cache(kmalloc_caches[type][6]); |
a5a84755 | 4731 | |
f9f58285 | 4732 | pr_err("\nB. Corruption after free\n"); |
a5a84755 CL |
4733 | p = kzalloc(128, GFP_KERNEL); |
4734 | kfree(p); | |
4735 | *p = 0x78; | |
f9f58285 | 4736 | pr_err("1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p); |
cc252eae | 4737 | validate_slab_cache(kmalloc_caches[type][7]); |
a5a84755 CL |
4738 | |
4739 | p = kzalloc(256, GFP_KERNEL); | |
4740 | kfree(p); | |
4741 | p[50] = 0x9a; | |
f9f58285 | 4742 | pr_err("\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p); |
cc252eae | 4743 | validate_slab_cache(kmalloc_caches[type][8]); |
a5a84755 CL |
4744 | |
4745 | p = kzalloc(512, GFP_KERNEL); | |
4746 | kfree(p); | |
4747 | p[512] = 0xab; | |
f9f58285 | 4748 | pr_err("\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p); |
cc252eae | 4749 | validate_slab_cache(kmalloc_caches[type][9]); |
a5a84755 CL |
4750 | } |
4751 | #else | |
4752 | #ifdef CONFIG_SYSFS | |
4753 | static void resiliency_test(void) {}; | |
4754 | #endif | |
4755 | #endif | |
4756 | ||
ab4d5ed5 | 4757 | #ifdef CONFIG_SYSFS |
81819f0f | 4758 | enum slab_stat_type { |
205ab99d CL |
4759 | SL_ALL, /* All slabs */ |
4760 | SL_PARTIAL, /* Only partially allocated slabs */ | |
4761 | SL_CPU, /* Only slabs used for cpu caches */ | |
4762 | SL_OBJECTS, /* Determine allocated objects not slabs */ | |
4763 | SL_TOTAL /* Determine object capacity not slabs */ | |
81819f0f CL |
4764 | }; |
4765 | ||
205ab99d | 4766 | #define SO_ALL (1 << SL_ALL) |
81819f0f CL |
4767 | #define SO_PARTIAL (1 << SL_PARTIAL) |
4768 | #define SO_CPU (1 << SL_CPU) | |
4769 | #define SO_OBJECTS (1 << SL_OBJECTS) | |
205ab99d | 4770 | #define SO_TOTAL (1 << SL_TOTAL) |
81819f0f | 4771 | |
1663f26d TH |
4772 | #ifdef CONFIG_MEMCG |
4773 | static bool memcg_sysfs_enabled = IS_ENABLED(CONFIG_SLUB_MEMCG_SYSFS_ON); | |
4774 | ||
4775 | static int __init setup_slub_memcg_sysfs(char *str) | |
4776 | { | |
4777 | int v; | |
4778 | ||
4779 | if (get_option(&str, &v) > 0) | |
4780 | memcg_sysfs_enabled = v; | |
4781 | ||
4782 | return 1; | |
4783 | } | |
4784 | ||
4785 | __setup("slub_memcg_sysfs=", setup_slub_memcg_sysfs); | |
4786 | #endif | |
4787 | ||
62e5c4b4 CG |
4788 | static ssize_t show_slab_objects(struct kmem_cache *s, |
4789 | char *buf, unsigned long flags) | |
81819f0f CL |
4790 | { |
4791 | unsigned long total = 0; | |
81819f0f CL |
4792 | int node; |
4793 | int x; | |
4794 | unsigned long *nodes; | |
81819f0f | 4795 | |
6396bb22 | 4796 | nodes = kcalloc(nr_node_ids, sizeof(unsigned long), GFP_KERNEL); |
62e5c4b4 CG |
4797 | if (!nodes) |
4798 | return -ENOMEM; | |
81819f0f | 4799 | |
205ab99d CL |
4800 | if (flags & SO_CPU) { |
4801 | int cpu; | |
81819f0f | 4802 | |
205ab99d | 4803 | for_each_possible_cpu(cpu) { |
d0e0ac97 CG |
4804 | struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, |
4805 | cpu); | |
ec3ab083 | 4806 | int node; |
49e22585 | 4807 | struct page *page; |
dfb4f096 | 4808 | |
4db0c3c2 | 4809 | page = READ_ONCE(c->page); |
ec3ab083 CL |
4810 | if (!page) |
4811 | continue; | |
205ab99d | 4812 | |
ec3ab083 CL |
4813 | node = page_to_nid(page); |
4814 | if (flags & SO_TOTAL) | |
4815 | x = page->objects; | |
4816 | else if (flags & SO_OBJECTS) | |
4817 | x = page->inuse; | |
4818 | else | |
4819 | x = 1; | |
49e22585 | 4820 | |
ec3ab083 CL |
4821 | total += x; |
4822 | nodes[node] += x; | |
4823 | ||
a93cf07b | 4824 | page = slub_percpu_partial_read_once(c); |
49e22585 | 4825 | if (page) { |
8afb1474 LZ |
4826 | node = page_to_nid(page); |
4827 | if (flags & SO_TOTAL) | |
4828 | WARN_ON_ONCE(1); | |
4829 | else if (flags & SO_OBJECTS) | |
4830 | WARN_ON_ONCE(1); | |
4831 | else | |
4832 | x = page->pages; | |
bc6697d8 ED |
4833 | total += x; |
4834 | nodes[node] += x; | |
49e22585 | 4835 | } |
81819f0f CL |
4836 | } |
4837 | } | |
4838 | ||
bfc8c901 | 4839 | get_online_mems(); |
ab4d5ed5 | 4840 | #ifdef CONFIG_SLUB_DEBUG |
205ab99d | 4841 | if (flags & SO_ALL) { |
fa45dc25 CL |
4842 | struct kmem_cache_node *n; |
4843 | ||
4844 | for_each_kmem_cache_node(s, node, n) { | |
205ab99d | 4845 | |
d0e0ac97 CG |
4846 | if (flags & SO_TOTAL) |
4847 | x = atomic_long_read(&n->total_objects); | |
4848 | else if (flags & SO_OBJECTS) | |
4849 | x = atomic_long_read(&n->total_objects) - | |
4850 | count_partial(n, count_free); | |
81819f0f | 4851 | else |
205ab99d | 4852 | x = atomic_long_read(&n->nr_slabs); |
81819f0f CL |
4853 | total += x; |
4854 | nodes[node] += x; | |
4855 | } | |
4856 | ||
ab4d5ed5 CL |
4857 | } else |
4858 | #endif | |
4859 | if (flags & SO_PARTIAL) { | |
fa45dc25 | 4860 | struct kmem_cache_node *n; |
81819f0f | 4861 | |
fa45dc25 | 4862 | for_each_kmem_cache_node(s, node, n) { |
205ab99d CL |
4863 | if (flags & SO_TOTAL) |
4864 | x = count_partial(n, count_total); | |
4865 | else if (flags & SO_OBJECTS) | |
4866 | x = count_partial(n, count_inuse); | |
81819f0f | 4867 | else |
205ab99d | 4868 | x = n->nr_partial; |
81819f0f CL |
4869 | total += x; |
4870 | nodes[node] += x; | |
4871 | } | |
4872 | } | |
81819f0f CL |
4873 | x = sprintf(buf, "%lu", total); |
4874 | #ifdef CONFIG_NUMA | |
fa45dc25 | 4875 | for (node = 0; node < nr_node_ids; node++) |
81819f0f CL |
4876 | if (nodes[node]) |
4877 | x += sprintf(buf + x, " N%d=%lu", | |
4878 | node, nodes[node]); | |
4879 | #endif | |
bfc8c901 | 4880 | put_online_mems(); |
81819f0f CL |
4881 | kfree(nodes); |
4882 | return x + sprintf(buf + x, "\n"); | |
4883 | } | |
4884 | ||
ab4d5ed5 | 4885 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
4886 | static int any_slab_objects(struct kmem_cache *s) |
4887 | { | |
4888 | int node; | |
fa45dc25 | 4889 | struct kmem_cache_node *n; |
81819f0f | 4890 | |
fa45dc25 | 4891 | for_each_kmem_cache_node(s, node, n) |
4ea33e2d | 4892 | if (atomic_long_read(&n->total_objects)) |
81819f0f | 4893 | return 1; |
fa45dc25 | 4894 | |
81819f0f CL |
4895 | return 0; |
4896 | } | |
ab4d5ed5 | 4897 | #endif |
81819f0f CL |
4898 | |
4899 | #define to_slab_attr(n) container_of(n, struct slab_attribute, attr) | |
497888cf | 4900 | #define to_slab(n) container_of(n, struct kmem_cache, kobj) |
81819f0f CL |
4901 | |
4902 | struct slab_attribute { | |
4903 | struct attribute attr; | |
4904 | ssize_t (*show)(struct kmem_cache *s, char *buf); | |
4905 | ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); | |
4906 | }; | |
4907 | ||
4908 | #define SLAB_ATTR_RO(_name) \ | |
ab067e99 VK |
4909 | static struct slab_attribute _name##_attr = \ |
4910 | __ATTR(_name, 0400, _name##_show, NULL) | |
81819f0f CL |
4911 | |
4912 | #define SLAB_ATTR(_name) \ | |
4913 | static struct slab_attribute _name##_attr = \ | |
ab067e99 | 4914 | __ATTR(_name, 0600, _name##_show, _name##_store) |
81819f0f | 4915 | |
81819f0f CL |
4916 | static ssize_t slab_size_show(struct kmem_cache *s, char *buf) |
4917 | { | |
44065b2e | 4918 | return sprintf(buf, "%u\n", s->size); |
81819f0f CL |
4919 | } |
4920 | SLAB_ATTR_RO(slab_size); | |
4921 | ||
4922 | static ssize_t align_show(struct kmem_cache *s, char *buf) | |
4923 | { | |
3a3791ec | 4924 | return sprintf(buf, "%u\n", s->align); |
81819f0f CL |
4925 | } |
4926 | SLAB_ATTR_RO(align); | |
4927 | ||
4928 | static ssize_t object_size_show(struct kmem_cache *s, char *buf) | |
4929 | { | |
1b473f29 | 4930 | return sprintf(buf, "%u\n", s->object_size); |
81819f0f CL |
4931 | } |
4932 | SLAB_ATTR_RO(object_size); | |
4933 | ||
4934 | static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) | |
4935 | { | |
19af27af | 4936 | return sprintf(buf, "%u\n", oo_objects(s->oo)); |
81819f0f CL |
4937 | } |
4938 | SLAB_ATTR_RO(objs_per_slab); | |
4939 | ||
06b285dc CL |
4940 | static ssize_t order_store(struct kmem_cache *s, |
4941 | const char *buf, size_t length) | |
4942 | { | |
19af27af | 4943 | unsigned int order; |
0121c619 CL |
4944 | int err; |
4945 | ||
19af27af | 4946 | err = kstrtouint(buf, 10, &order); |
0121c619 CL |
4947 | if (err) |
4948 | return err; | |
06b285dc CL |
4949 | |
4950 | if (order > slub_max_order || order < slub_min_order) | |
4951 | return -EINVAL; | |
4952 | ||
4953 | calculate_sizes(s, order); | |
4954 | return length; | |
4955 | } | |
4956 | ||
81819f0f CL |
4957 | static ssize_t order_show(struct kmem_cache *s, char *buf) |
4958 | { | |
19af27af | 4959 | return sprintf(buf, "%u\n", oo_order(s->oo)); |
81819f0f | 4960 | } |
06b285dc | 4961 | SLAB_ATTR(order); |
81819f0f | 4962 | |
73d342b1 DR |
4963 | static ssize_t min_partial_show(struct kmem_cache *s, char *buf) |
4964 | { | |
4965 | return sprintf(buf, "%lu\n", s->min_partial); | |
4966 | } | |
4967 | ||
4968 | static ssize_t min_partial_store(struct kmem_cache *s, const char *buf, | |
4969 | size_t length) | |
4970 | { | |
4971 | unsigned long min; | |
4972 | int err; | |
4973 | ||
3dbb95f7 | 4974 | err = kstrtoul(buf, 10, &min); |
73d342b1 DR |
4975 | if (err) |
4976 | return err; | |
4977 | ||
c0bdb232 | 4978 | set_min_partial(s, min); |
73d342b1 DR |
4979 | return length; |
4980 | } | |
4981 | SLAB_ATTR(min_partial); | |
4982 | ||
49e22585 CL |
4983 | static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf) |
4984 | { | |
e6d0e1dc | 4985 | return sprintf(buf, "%u\n", slub_cpu_partial(s)); |
49e22585 CL |
4986 | } |
4987 | ||
4988 | static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, | |
4989 | size_t length) | |
4990 | { | |
e5d9998f | 4991 | unsigned int objects; |
49e22585 CL |
4992 | int err; |
4993 | ||
e5d9998f | 4994 | err = kstrtouint(buf, 10, &objects); |
49e22585 CL |
4995 | if (err) |
4996 | return err; | |
345c905d | 4997 | if (objects && !kmem_cache_has_cpu_partial(s)) |
74ee4ef1 | 4998 | return -EINVAL; |
49e22585 | 4999 | |
e6d0e1dc | 5000 | slub_set_cpu_partial(s, objects); |
49e22585 CL |
5001 | flush_all(s); |
5002 | return length; | |
5003 | } | |
5004 | SLAB_ATTR(cpu_partial); | |
5005 | ||
81819f0f CL |
5006 | static ssize_t ctor_show(struct kmem_cache *s, char *buf) |
5007 | { | |
62c70bce JP |
5008 | if (!s->ctor) |
5009 | return 0; | |
5010 | return sprintf(buf, "%pS\n", s->ctor); | |
81819f0f CL |
5011 | } |
5012 | SLAB_ATTR_RO(ctor); | |
5013 | ||
81819f0f CL |
5014 | static ssize_t aliases_show(struct kmem_cache *s, char *buf) |
5015 | { | |
4307c14f | 5016 | return sprintf(buf, "%d\n", s->refcount < 0 ? 0 : s->refcount - 1); |
81819f0f CL |
5017 | } |
5018 | SLAB_ATTR_RO(aliases); | |
5019 | ||
81819f0f CL |
5020 | static ssize_t partial_show(struct kmem_cache *s, char *buf) |
5021 | { | |
d9acf4b7 | 5022 | return show_slab_objects(s, buf, SO_PARTIAL); |
81819f0f CL |
5023 | } |
5024 | SLAB_ATTR_RO(partial); | |
5025 | ||
5026 | static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) | |
5027 | { | |
d9acf4b7 | 5028 | return show_slab_objects(s, buf, SO_CPU); |
81819f0f CL |
5029 | } |
5030 | SLAB_ATTR_RO(cpu_slabs); | |
5031 | ||
5032 | static ssize_t objects_show(struct kmem_cache *s, char *buf) | |
5033 | { | |
205ab99d | 5034 | return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); |
81819f0f CL |
5035 | } |
5036 | SLAB_ATTR_RO(objects); | |
5037 | ||
205ab99d CL |
5038 | static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) |
5039 | { | |
5040 | return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); | |
5041 | } | |
5042 | SLAB_ATTR_RO(objects_partial); | |
5043 | ||
49e22585 CL |
5044 | static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf) |
5045 | { | |
5046 | int objects = 0; | |
5047 | int pages = 0; | |
5048 | int cpu; | |
5049 | int len; | |
5050 | ||
5051 | for_each_online_cpu(cpu) { | |
a93cf07b WY |
5052 | struct page *page; |
5053 | ||
5054 | page = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); | |
49e22585 CL |
5055 | |
5056 | if (page) { | |
5057 | pages += page->pages; | |
5058 | objects += page->pobjects; | |
5059 | } | |
5060 | } | |
5061 | ||
5062 | len = sprintf(buf, "%d(%d)", objects, pages); | |
5063 | ||
5064 | #ifdef CONFIG_SMP | |
5065 | for_each_online_cpu(cpu) { | |
a93cf07b WY |
5066 | struct page *page; |
5067 | ||
5068 | page = slub_percpu_partial(per_cpu_ptr(s->cpu_slab, cpu)); | |
49e22585 CL |
5069 | |
5070 | if (page && len < PAGE_SIZE - 20) | |
5071 | len += sprintf(buf + len, " C%d=%d(%d)", cpu, | |
5072 | page->pobjects, page->pages); | |
5073 | } | |
5074 | #endif | |
5075 | return len + sprintf(buf + len, "\n"); | |
5076 | } | |
5077 | SLAB_ATTR_RO(slabs_cpu_partial); | |
5078 | ||
a5a84755 CL |
5079 | static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) |
5080 | { | |
5081 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); | |
5082 | } | |
5083 | ||
5084 | static ssize_t reclaim_account_store(struct kmem_cache *s, | |
5085 | const char *buf, size_t length) | |
5086 | { | |
5087 | s->flags &= ~SLAB_RECLAIM_ACCOUNT; | |
5088 | if (buf[0] == '1') | |
5089 | s->flags |= SLAB_RECLAIM_ACCOUNT; | |
5090 | return length; | |
5091 | } | |
5092 | SLAB_ATTR(reclaim_account); | |
5093 | ||
5094 | static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) | |
5095 | { | |
5096 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); | |
5097 | } | |
5098 | SLAB_ATTR_RO(hwcache_align); | |
5099 | ||
5100 | #ifdef CONFIG_ZONE_DMA | |
5101 | static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) | |
5102 | { | |
5103 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); | |
5104 | } | |
5105 | SLAB_ATTR_RO(cache_dma); | |
5106 | #endif | |
5107 | ||
8eb8284b DW |
5108 | static ssize_t usersize_show(struct kmem_cache *s, char *buf) |
5109 | { | |
7bbdb81e | 5110 | return sprintf(buf, "%u\n", s->usersize); |
8eb8284b DW |
5111 | } |
5112 | SLAB_ATTR_RO(usersize); | |
5113 | ||
a5a84755 CL |
5114 | static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) |
5115 | { | |
5f0d5a3a | 5116 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_TYPESAFE_BY_RCU)); |
a5a84755 CL |
5117 | } |
5118 | SLAB_ATTR_RO(destroy_by_rcu); | |
5119 | ||
ab4d5ed5 | 5120 | #ifdef CONFIG_SLUB_DEBUG |
a5a84755 CL |
5121 | static ssize_t slabs_show(struct kmem_cache *s, char *buf) |
5122 | { | |
5123 | return show_slab_objects(s, buf, SO_ALL); | |
5124 | } | |
5125 | SLAB_ATTR_RO(slabs); | |
5126 | ||
205ab99d CL |
5127 | static ssize_t total_objects_show(struct kmem_cache *s, char *buf) |
5128 | { | |
5129 | return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); | |
5130 | } | |
5131 | SLAB_ATTR_RO(total_objects); | |
5132 | ||
81819f0f CL |
5133 | static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) |
5134 | { | |
becfda68 | 5135 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_CONSISTENCY_CHECKS)); |
81819f0f CL |
5136 | } |
5137 | ||
5138 | static ssize_t sanity_checks_store(struct kmem_cache *s, | |
5139 | const char *buf, size_t length) | |
5140 | { | |
becfda68 | 5141 | s->flags &= ~SLAB_CONSISTENCY_CHECKS; |
b789ef51 CL |
5142 | if (buf[0] == '1') { |
5143 | s->flags &= ~__CMPXCHG_DOUBLE; | |
becfda68 | 5144 | s->flags |= SLAB_CONSISTENCY_CHECKS; |
b789ef51 | 5145 | } |
81819f0f CL |
5146 | return length; |
5147 | } | |
5148 | SLAB_ATTR(sanity_checks); | |
5149 | ||
5150 | static ssize_t trace_show(struct kmem_cache *s, char *buf) | |
5151 | { | |
5152 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE)); | |
5153 | } | |
5154 | ||
5155 | static ssize_t trace_store(struct kmem_cache *s, const char *buf, | |
5156 | size_t length) | |
5157 | { | |
c9e16131 CL |
5158 | /* |
5159 | * Tracing a merged cache is going to give confusing results | |
5160 | * as well as cause other issues like converting a mergeable | |
5161 | * cache into an umergeable one. | |
5162 | */ | |
5163 | if (s->refcount > 1) | |
5164 | return -EINVAL; | |
5165 | ||
81819f0f | 5166 | s->flags &= ~SLAB_TRACE; |
b789ef51 CL |
5167 | if (buf[0] == '1') { |
5168 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 5169 | s->flags |= SLAB_TRACE; |
b789ef51 | 5170 | } |
81819f0f CL |
5171 | return length; |
5172 | } | |
5173 | SLAB_ATTR(trace); | |
5174 | ||
81819f0f CL |
5175 | static ssize_t red_zone_show(struct kmem_cache *s, char *buf) |
5176 | { | |
5177 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); | |
5178 | } | |
5179 | ||
5180 | static ssize_t red_zone_store(struct kmem_cache *s, | |
5181 | const char *buf, size_t length) | |
5182 | { | |
5183 | if (any_slab_objects(s)) | |
5184 | return -EBUSY; | |
5185 | ||
5186 | s->flags &= ~SLAB_RED_ZONE; | |
b789ef51 | 5187 | if (buf[0] == '1') { |
81819f0f | 5188 | s->flags |= SLAB_RED_ZONE; |
b789ef51 | 5189 | } |
06b285dc | 5190 | calculate_sizes(s, -1); |
81819f0f CL |
5191 | return length; |
5192 | } | |
5193 | SLAB_ATTR(red_zone); | |
5194 | ||
5195 | static ssize_t poison_show(struct kmem_cache *s, char *buf) | |
5196 | { | |
5197 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON)); | |
5198 | } | |
5199 | ||
5200 | static ssize_t poison_store(struct kmem_cache *s, | |
5201 | const char *buf, size_t length) | |
5202 | { | |
5203 | if (any_slab_objects(s)) | |
5204 | return -EBUSY; | |
5205 | ||
5206 | s->flags &= ~SLAB_POISON; | |
b789ef51 | 5207 | if (buf[0] == '1') { |
81819f0f | 5208 | s->flags |= SLAB_POISON; |
b789ef51 | 5209 | } |
06b285dc | 5210 | calculate_sizes(s, -1); |
81819f0f CL |
5211 | return length; |
5212 | } | |
5213 | SLAB_ATTR(poison); | |
5214 | ||
5215 | static ssize_t store_user_show(struct kmem_cache *s, char *buf) | |
5216 | { | |
5217 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); | |
5218 | } | |
5219 | ||
5220 | static ssize_t store_user_store(struct kmem_cache *s, | |
5221 | const char *buf, size_t length) | |
5222 | { | |
5223 | if (any_slab_objects(s)) | |
5224 | return -EBUSY; | |
5225 | ||
5226 | s->flags &= ~SLAB_STORE_USER; | |
b789ef51 CL |
5227 | if (buf[0] == '1') { |
5228 | s->flags &= ~__CMPXCHG_DOUBLE; | |
81819f0f | 5229 | s->flags |= SLAB_STORE_USER; |
b789ef51 | 5230 | } |
06b285dc | 5231 | calculate_sizes(s, -1); |
81819f0f CL |
5232 | return length; |
5233 | } | |
5234 | SLAB_ATTR(store_user); | |
5235 | ||
53e15af0 CL |
5236 | static ssize_t validate_show(struct kmem_cache *s, char *buf) |
5237 | { | |
5238 | return 0; | |
5239 | } | |
5240 | ||
5241 | static ssize_t validate_store(struct kmem_cache *s, | |
5242 | const char *buf, size_t length) | |
5243 | { | |
434e245d CL |
5244 | int ret = -EINVAL; |
5245 | ||
5246 | if (buf[0] == '1') { | |
5247 | ret = validate_slab_cache(s); | |
5248 | if (ret >= 0) | |
5249 | ret = length; | |
5250 | } | |
5251 | return ret; | |
53e15af0 CL |
5252 | } |
5253 | SLAB_ATTR(validate); | |
a5a84755 CL |
5254 | |
5255 | static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf) | |
5256 | { | |
5257 | if (!(s->flags & SLAB_STORE_USER)) | |
5258 | return -ENOSYS; | |
5259 | return list_locations(s, buf, TRACK_ALLOC); | |
5260 | } | |
5261 | SLAB_ATTR_RO(alloc_calls); | |
5262 | ||
5263 | static ssize_t free_calls_show(struct kmem_cache *s, char *buf) | |
5264 | { | |
5265 | if (!(s->flags & SLAB_STORE_USER)) | |
5266 | return -ENOSYS; | |
5267 | return list_locations(s, buf, TRACK_FREE); | |
5268 | } | |
5269 | SLAB_ATTR_RO(free_calls); | |
5270 | #endif /* CONFIG_SLUB_DEBUG */ | |
5271 | ||
5272 | #ifdef CONFIG_FAILSLAB | |
5273 | static ssize_t failslab_show(struct kmem_cache *s, char *buf) | |
5274 | { | |
5275 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); | |
5276 | } | |
5277 | ||
5278 | static ssize_t failslab_store(struct kmem_cache *s, const char *buf, | |
5279 | size_t length) | |
5280 | { | |
c9e16131 CL |
5281 | if (s->refcount > 1) |
5282 | return -EINVAL; | |
5283 | ||
a5a84755 CL |
5284 | s->flags &= ~SLAB_FAILSLAB; |
5285 | if (buf[0] == '1') | |
5286 | s->flags |= SLAB_FAILSLAB; | |
5287 | return length; | |
5288 | } | |
5289 | SLAB_ATTR(failslab); | |
ab4d5ed5 | 5290 | #endif |
53e15af0 | 5291 | |
2086d26a CL |
5292 | static ssize_t shrink_show(struct kmem_cache *s, char *buf) |
5293 | { | |
5294 | return 0; | |
5295 | } | |
5296 | ||
5297 | static ssize_t shrink_store(struct kmem_cache *s, | |
5298 | const char *buf, size_t length) | |
5299 | { | |
832f37f5 VD |
5300 | if (buf[0] == '1') |
5301 | kmem_cache_shrink(s); | |
5302 | else | |
2086d26a CL |
5303 | return -EINVAL; |
5304 | return length; | |
5305 | } | |
5306 | SLAB_ATTR(shrink); | |
5307 | ||
81819f0f | 5308 | #ifdef CONFIG_NUMA |
9824601e | 5309 | static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) |
81819f0f | 5310 | { |
eb7235eb | 5311 | return sprintf(buf, "%u\n", s->remote_node_defrag_ratio / 10); |
81819f0f CL |
5312 | } |
5313 | ||
9824601e | 5314 | static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, |
81819f0f CL |
5315 | const char *buf, size_t length) |
5316 | { | |
eb7235eb | 5317 | unsigned int ratio; |
0121c619 CL |
5318 | int err; |
5319 | ||
eb7235eb | 5320 | err = kstrtouint(buf, 10, &ratio); |
0121c619 CL |
5321 | if (err) |
5322 | return err; | |
eb7235eb AD |
5323 | if (ratio > 100) |
5324 | return -ERANGE; | |
0121c619 | 5325 | |
eb7235eb | 5326 | s->remote_node_defrag_ratio = ratio * 10; |
81819f0f | 5327 | |
81819f0f CL |
5328 | return length; |
5329 | } | |
9824601e | 5330 | SLAB_ATTR(remote_node_defrag_ratio); |
81819f0f CL |
5331 | #endif |
5332 | ||
8ff12cfc | 5333 | #ifdef CONFIG_SLUB_STATS |
8ff12cfc CL |
5334 | static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) |
5335 | { | |
5336 | unsigned long sum = 0; | |
5337 | int cpu; | |
5338 | int len; | |
6da2ec56 | 5339 | int *data = kmalloc_array(nr_cpu_ids, sizeof(int), GFP_KERNEL); |
8ff12cfc CL |
5340 | |
5341 | if (!data) | |
5342 | return -ENOMEM; | |
5343 | ||
5344 | for_each_online_cpu(cpu) { | |
9dfc6e68 | 5345 | unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si]; |
8ff12cfc CL |
5346 | |
5347 | data[cpu] = x; | |
5348 | sum += x; | |
5349 | } | |
5350 | ||
5351 | len = sprintf(buf, "%lu", sum); | |
5352 | ||
50ef37b9 | 5353 | #ifdef CONFIG_SMP |
8ff12cfc CL |
5354 | for_each_online_cpu(cpu) { |
5355 | if (data[cpu] && len < PAGE_SIZE - 20) | |
50ef37b9 | 5356 | len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]); |
8ff12cfc | 5357 | } |
50ef37b9 | 5358 | #endif |
8ff12cfc CL |
5359 | kfree(data); |
5360 | return len + sprintf(buf + len, "\n"); | |
5361 | } | |
5362 | ||
78eb00cc DR |
5363 | static void clear_stat(struct kmem_cache *s, enum stat_item si) |
5364 | { | |
5365 | int cpu; | |
5366 | ||
5367 | for_each_online_cpu(cpu) | |
9dfc6e68 | 5368 | per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0; |
78eb00cc DR |
5369 | } |
5370 | ||
8ff12cfc CL |
5371 | #define STAT_ATTR(si, text) \ |
5372 | static ssize_t text##_show(struct kmem_cache *s, char *buf) \ | |
5373 | { \ | |
5374 | return show_stat(s, buf, si); \ | |
5375 | } \ | |
78eb00cc DR |
5376 | static ssize_t text##_store(struct kmem_cache *s, \ |
5377 | const char *buf, size_t length) \ | |
5378 | { \ | |
5379 | if (buf[0] != '0') \ | |
5380 | return -EINVAL; \ | |
5381 | clear_stat(s, si); \ | |
5382 | return length; \ | |
5383 | } \ | |
5384 | SLAB_ATTR(text); \ | |
8ff12cfc CL |
5385 | |
5386 | STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); | |
5387 | STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); | |
5388 | STAT_ATTR(FREE_FASTPATH, free_fastpath); | |
5389 | STAT_ATTR(FREE_SLOWPATH, free_slowpath); | |
5390 | STAT_ATTR(FREE_FROZEN, free_frozen); | |
5391 | STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); | |
5392 | STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); | |
5393 | STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); | |
5394 | STAT_ATTR(ALLOC_SLAB, alloc_slab); | |
5395 | STAT_ATTR(ALLOC_REFILL, alloc_refill); | |
e36a2652 | 5396 | STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch); |
8ff12cfc CL |
5397 | STAT_ATTR(FREE_SLAB, free_slab); |
5398 | STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); | |
5399 | STAT_ATTR(DEACTIVATE_FULL, deactivate_full); | |
5400 | STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); | |
5401 | STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); | |
5402 | STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); | |
5403 | STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); | |
03e404af | 5404 | STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass); |
65c3376a | 5405 | STAT_ATTR(ORDER_FALLBACK, order_fallback); |
b789ef51 CL |
5406 | STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); |
5407 | STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); | |
49e22585 CL |
5408 | STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); |
5409 | STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); | |
8028dcea AS |
5410 | STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); |
5411 | STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); | |
8ff12cfc CL |
5412 | #endif |
5413 | ||
06428780 | 5414 | static struct attribute *slab_attrs[] = { |
81819f0f CL |
5415 | &slab_size_attr.attr, |
5416 | &object_size_attr.attr, | |
5417 | &objs_per_slab_attr.attr, | |
5418 | &order_attr.attr, | |
73d342b1 | 5419 | &min_partial_attr.attr, |
49e22585 | 5420 | &cpu_partial_attr.attr, |
81819f0f | 5421 | &objects_attr.attr, |
205ab99d | 5422 | &objects_partial_attr.attr, |
81819f0f CL |
5423 | &partial_attr.attr, |
5424 | &cpu_slabs_attr.attr, | |
5425 | &ctor_attr.attr, | |
81819f0f CL |
5426 | &aliases_attr.attr, |
5427 | &align_attr.attr, | |
81819f0f CL |
5428 | &hwcache_align_attr.attr, |
5429 | &reclaim_account_attr.attr, | |
5430 | &destroy_by_rcu_attr.attr, | |
a5a84755 | 5431 | &shrink_attr.attr, |
49e22585 | 5432 | &slabs_cpu_partial_attr.attr, |
ab4d5ed5 | 5433 | #ifdef CONFIG_SLUB_DEBUG |
a5a84755 CL |
5434 | &total_objects_attr.attr, |
5435 | &slabs_attr.attr, | |
5436 | &sanity_checks_attr.attr, | |
5437 | &trace_attr.attr, | |
81819f0f CL |
5438 | &red_zone_attr.attr, |
5439 | &poison_attr.attr, | |
5440 | &store_user_attr.attr, | |
53e15af0 | 5441 | &validate_attr.attr, |
88a420e4 CL |
5442 | &alloc_calls_attr.attr, |
5443 | &free_calls_attr.attr, | |
ab4d5ed5 | 5444 | #endif |
81819f0f CL |
5445 | #ifdef CONFIG_ZONE_DMA |
5446 | &cache_dma_attr.attr, | |
5447 | #endif | |
5448 | #ifdef CONFIG_NUMA | |
9824601e | 5449 | &remote_node_defrag_ratio_attr.attr, |
8ff12cfc CL |
5450 | #endif |
5451 | #ifdef CONFIG_SLUB_STATS | |
5452 | &alloc_fastpath_attr.attr, | |
5453 | &alloc_slowpath_attr.attr, | |
5454 | &free_fastpath_attr.attr, | |
5455 | &free_slowpath_attr.attr, | |
5456 | &free_frozen_attr.attr, | |
5457 | &free_add_partial_attr.attr, | |
5458 | &free_remove_partial_attr.attr, | |
5459 | &alloc_from_partial_attr.attr, | |
5460 | &alloc_slab_attr.attr, | |
5461 | &alloc_refill_attr.attr, | |
e36a2652 | 5462 | &alloc_node_mismatch_attr.attr, |
8ff12cfc CL |
5463 | &free_slab_attr.attr, |
5464 | &cpuslab_flush_attr.attr, | |
5465 | &deactivate_full_attr.attr, | |
5466 | &deactivate_empty_attr.attr, | |
5467 | &deactivate_to_head_attr.attr, | |
5468 | &deactivate_to_tail_attr.attr, | |
5469 | &deactivate_remote_frees_attr.attr, | |
03e404af | 5470 | &deactivate_bypass_attr.attr, |
65c3376a | 5471 | &order_fallback_attr.attr, |
b789ef51 CL |
5472 | &cmpxchg_double_fail_attr.attr, |
5473 | &cmpxchg_double_cpu_fail_attr.attr, | |
49e22585 CL |
5474 | &cpu_partial_alloc_attr.attr, |
5475 | &cpu_partial_free_attr.attr, | |
8028dcea AS |
5476 | &cpu_partial_node_attr.attr, |
5477 | &cpu_partial_drain_attr.attr, | |
81819f0f | 5478 | #endif |
4c13dd3b DM |
5479 | #ifdef CONFIG_FAILSLAB |
5480 | &failslab_attr.attr, | |
5481 | #endif | |
8eb8284b | 5482 | &usersize_attr.attr, |
4c13dd3b | 5483 | |
81819f0f CL |
5484 | NULL |
5485 | }; | |
5486 | ||
1fdaaa23 | 5487 | static const struct attribute_group slab_attr_group = { |
81819f0f CL |
5488 | .attrs = slab_attrs, |
5489 | }; | |
5490 | ||
5491 | static ssize_t slab_attr_show(struct kobject *kobj, | |
5492 | struct attribute *attr, | |
5493 | char *buf) | |
5494 | { | |
5495 | struct slab_attribute *attribute; | |
5496 | struct kmem_cache *s; | |
5497 | int err; | |
5498 | ||
5499 | attribute = to_slab_attr(attr); | |
5500 | s = to_slab(kobj); | |
5501 | ||
5502 | if (!attribute->show) | |
5503 | return -EIO; | |
5504 | ||
5505 | err = attribute->show(s, buf); | |
5506 | ||
5507 | return err; | |
5508 | } | |
5509 | ||
5510 | static ssize_t slab_attr_store(struct kobject *kobj, | |
5511 | struct attribute *attr, | |
5512 | const char *buf, size_t len) | |
5513 | { | |
5514 | struct slab_attribute *attribute; | |
5515 | struct kmem_cache *s; | |
5516 | int err; | |
5517 | ||
5518 | attribute = to_slab_attr(attr); | |
5519 | s = to_slab(kobj); | |
5520 | ||
5521 | if (!attribute->store) | |
5522 | return -EIO; | |
5523 | ||
5524 | err = attribute->store(s, buf, len); | |
127424c8 | 5525 | #ifdef CONFIG_MEMCG |
107dab5c | 5526 | if (slab_state >= FULL && err >= 0 && is_root_cache(s)) { |
426589f5 | 5527 | struct kmem_cache *c; |
81819f0f | 5528 | |
107dab5c GC |
5529 | mutex_lock(&slab_mutex); |
5530 | if (s->max_attr_size < len) | |
5531 | s->max_attr_size = len; | |
5532 | ||
ebe945c2 GC |
5533 | /* |
5534 | * This is a best effort propagation, so this function's return | |
5535 | * value will be determined by the parent cache only. This is | |
5536 | * basically because not all attributes will have a well | |
5537 | * defined semantics for rollbacks - most of the actions will | |
5538 | * have permanent effects. | |
5539 | * | |
5540 | * Returning the error value of any of the children that fail | |
5541 | * is not 100 % defined, in the sense that users seeing the | |
5542 | * error code won't be able to know anything about the state of | |
5543 | * the cache. | |
5544 | * | |
5545 | * Only returning the error code for the parent cache at least | |
5546 | * has well defined semantics. The cache being written to | |
5547 | * directly either failed or succeeded, in which case we loop | |
5548 | * through the descendants with best-effort propagation. | |
5549 | */ | |
426589f5 VD |
5550 | for_each_memcg_cache(c, s) |
5551 | attribute->store(c, buf, len); | |
107dab5c GC |
5552 | mutex_unlock(&slab_mutex); |
5553 | } | |
5554 | #endif | |
81819f0f CL |
5555 | return err; |
5556 | } | |
5557 | ||
107dab5c GC |
5558 | static void memcg_propagate_slab_attrs(struct kmem_cache *s) |
5559 | { | |
127424c8 | 5560 | #ifdef CONFIG_MEMCG |
107dab5c GC |
5561 | int i; |
5562 | char *buffer = NULL; | |
93030d83 | 5563 | struct kmem_cache *root_cache; |
107dab5c | 5564 | |
93030d83 | 5565 | if (is_root_cache(s)) |
107dab5c GC |
5566 | return; |
5567 | ||
f7ce3190 | 5568 | root_cache = s->memcg_params.root_cache; |
93030d83 | 5569 | |
107dab5c GC |
5570 | /* |
5571 | * This mean this cache had no attribute written. Therefore, no point | |
5572 | * in copying default values around | |
5573 | */ | |
93030d83 | 5574 | if (!root_cache->max_attr_size) |
107dab5c GC |
5575 | return; |
5576 | ||
5577 | for (i = 0; i < ARRAY_SIZE(slab_attrs); i++) { | |
5578 | char mbuf[64]; | |
5579 | char *buf; | |
5580 | struct slab_attribute *attr = to_slab_attr(slab_attrs[i]); | |
478fe303 | 5581 | ssize_t len; |
107dab5c GC |
5582 | |
5583 | if (!attr || !attr->store || !attr->show) | |
5584 | continue; | |
5585 | ||
5586 | /* | |
5587 | * It is really bad that we have to allocate here, so we will | |
5588 | * do it only as a fallback. If we actually allocate, though, | |
5589 | * we can just use the allocated buffer until the end. | |
5590 | * | |
5591 | * Most of the slub attributes will tend to be very small in | |
5592 | * size, but sysfs allows buffers up to a page, so they can | |
5593 | * theoretically happen. | |
5594 | */ | |
5595 | if (buffer) | |
5596 | buf = buffer; | |
93030d83 | 5597 | else if (root_cache->max_attr_size < ARRAY_SIZE(mbuf)) |
107dab5c GC |
5598 | buf = mbuf; |
5599 | else { | |
5600 | buffer = (char *) get_zeroed_page(GFP_KERNEL); | |
5601 | if (WARN_ON(!buffer)) | |
5602 | continue; | |
5603 | buf = buffer; | |
5604 | } | |
5605 | ||
478fe303 TG |
5606 | len = attr->show(root_cache, buf); |
5607 | if (len > 0) | |
5608 | attr->store(s, buf, len); | |
107dab5c GC |
5609 | } |
5610 | ||
5611 | if (buffer) | |
5612 | free_page((unsigned long)buffer); | |
5613 | #endif | |
5614 | } | |
5615 | ||
41a21285 CL |
5616 | static void kmem_cache_release(struct kobject *k) |
5617 | { | |
5618 | slab_kmem_cache_release(to_slab(k)); | |
5619 | } | |
5620 | ||
52cf25d0 | 5621 | static const struct sysfs_ops slab_sysfs_ops = { |
81819f0f CL |
5622 | .show = slab_attr_show, |
5623 | .store = slab_attr_store, | |
5624 | }; | |
5625 | ||
5626 | static struct kobj_type slab_ktype = { | |
5627 | .sysfs_ops = &slab_sysfs_ops, | |
41a21285 | 5628 | .release = kmem_cache_release, |
81819f0f CL |
5629 | }; |
5630 | ||
5631 | static int uevent_filter(struct kset *kset, struct kobject *kobj) | |
5632 | { | |
5633 | struct kobj_type *ktype = get_ktype(kobj); | |
5634 | ||
5635 | if (ktype == &slab_ktype) | |
5636 | return 1; | |
5637 | return 0; | |
5638 | } | |
5639 | ||
9cd43611 | 5640 | static const struct kset_uevent_ops slab_uevent_ops = { |
81819f0f CL |
5641 | .filter = uevent_filter, |
5642 | }; | |
5643 | ||
27c3a314 | 5644 | static struct kset *slab_kset; |
81819f0f | 5645 | |
9a41707b VD |
5646 | static inline struct kset *cache_kset(struct kmem_cache *s) |
5647 | { | |
127424c8 | 5648 | #ifdef CONFIG_MEMCG |
9a41707b | 5649 | if (!is_root_cache(s)) |
f7ce3190 | 5650 | return s->memcg_params.root_cache->memcg_kset; |
9a41707b VD |
5651 | #endif |
5652 | return slab_kset; | |
5653 | } | |
5654 | ||
81819f0f CL |
5655 | #define ID_STR_LENGTH 64 |
5656 | ||
5657 | /* Create a unique string id for a slab cache: | |
6446faa2 CL |
5658 | * |
5659 | * Format :[flags-]size | |
81819f0f CL |
5660 | */ |
5661 | static char *create_unique_id(struct kmem_cache *s) | |
5662 | { | |
5663 | char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); | |
5664 | char *p = name; | |
5665 | ||
5666 | BUG_ON(!name); | |
5667 | ||
5668 | *p++ = ':'; | |
5669 | /* | |
5670 | * First flags affecting slabcache operations. We will only | |
5671 | * get here for aliasable slabs so we do not need to support | |
5672 | * too many flags. The flags here must cover all flags that | |
5673 | * are matched during merging to guarantee that the id is | |
5674 | * unique. | |
5675 | */ | |
5676 | if (s->flags & SLAB_CACHE_DMA) | |
5677 | *p++ = 'd'; | |
5678 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
5679 | *p++ = 'a'; | |
becfda68 | 5680 | if (s->flags & SLAB_CONSISTENCY_CHECKS) |
81819f0f | 5681 | *p++ = 'F'; |
230e9fc2 VD |
5682 | if (s->flags & SLAB_ACCOUNT) |
5683 | *p++ = 'A'; | |
81819f0f CL |
5684 | if (p != name + 1) |
5685 | *p++ = '-'; | |
44065b2e | 5686 | p += sprintf(p, "%07u", s->size); |
2633d7a0 | 5687 | |
81819f0f CL |
5688 | BUG_ON(p > name + ID_STR_LENGTH - 1); |
5689 | return name; | |
5690 | } | |
5691 | ||
3b7b3140 TH |
5692 | static void sysfs_slab_remove_workfn(struct work_struct *work) |
5693 | { | |
5694 | struct kmem_cache *s = | |
5695 | container_of(work, struct kmem_cache, kobj_remove_work); | |
5696 | ||
5697 | if (!s->kobj.state_in_sysfs) | |
5698 | /* | |
5699 | * For a memcg cache, this may be called during | |
5700 | * deactivation and again on shutdown. Remove only once. | |
5701 | * A cache is never shut down before deactivation is | |
5702 | * complete, so no need to worry about synchronization. | |
5703 | */ | |
f6ba4880 | 5704 | goto out; |
3b7b3140 TH |
5705 | |
5706 | #ifdef CONFIG_MEMCG | |
5707 | kset_unregister(s->memcg_kset); | |
5708 | #endif | |
5709 | kobject_uevent(&s->kobj, KOBJ_REMOVE); | |
f6ba4880 | 5710 | out: |
3b7b3140 TH |
5711 | kobject_put(&s->kobj); |
5712 | } | |
5713 | ||
81819f0f CL |
5714 | static int sysfs_slab_add(struct kmem_cache *s) |
5715 | { | |
5716 | int err; | |
5717 | const char *name; | |
1663f26d | 5718 | struct kset *kset = cache_kset(s); |
45530c44 | 5719 | int unmergeable = slab_unmergeable(s); |
81819f0f | 5720 | |
3b7b3140 TH |
5721 | INIT_WORK(&s->kobj_remove_work, sysfs_slab_remove_workfn); |
5722 | ||
1663f26d TH |
5723 | if (!kset) { |
5724 | kobject_init(&s->kobj, &slab_ktype); | |
5725 | return 0; | |
5726 | } | |
5727 | ||
11066386 MC |
5728 | if (!unmergeable && disable_higher_order_debug && |
5729 | (slub_debug & DEBUG_METADATA_FLAGS)) | |
5730 | unmergeable = 1; | |
5731 | ||
81819f0f CL |
5732 | if (unmergeable) { |
5733 | /* | |
5734 | * Slabcache can never be merged so we can use the name proper. | |
5735 | * This is typically the case for debug situations. In that | |
5736 | * case we can catch duplicate names easily. | |
5737 | */ | |
27c3a314 | 5738 | sysfs_remove_link(&slab_kset->kobj, s->name); |
81819f0f CL |
5739 | name = s->name; |
5740 | } else { | |
5741 | /* | |
5742 | * Create a unique name for the slab as a target | |
5743 | * for the symlinks. | |
5744 | */ | |
5745 | name = create_unique_id(s); | |
5746 | } | |
5747 | ||
1663f26d | 5748 | s->kobj.kset = kset; |
26e4f205 | 5749 | err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, "%s", name); |
54b6a731 | 5750 | if (err) |
80da026a | 5751 | goto out; |
81819f0f CL |
5752 | |
5753 | err = sysfs_create_group(&s->kobj, &slab_attr_group); | |
54b6a731 DJ |
5754 | if (err) |
5755 | goto out_del_kobj; | |
9a41707b | 5756 | |
127424c8 | 5757 | #ifdef CONFIG_MEMCG |
1663f26d | 5758 | if (is_root_cache(s) && memcg_sysfs_enabled) { |
9a41707b VD |
5759 | s->memcg_kset = kset_create_and_add("cgroup", NULL, &s->kobj); |
5760 | if (!s->memcg_kset) { | |
54b6a731 DJ |
5761 | err = -ENOMEM; |
5762 | goto out_del_kobj; | |
9a41707b VD |
5763 | } |
5764 | } | |
5765 | #endif | |
5766 | ||
81819f0f CL |
5767 | kobject_uevent(&s->kobj, KOBJ_ADD); |
5768 | if (!unmergeable) { | |
5769 | /* Setup first alias */ | |
5770 | sysfs_slab_alias(s, s->name); | |
81819f0f | 5771 | } |
54b6a731 DJ |
5772 | out: |
5773 | if (!unmergeable) | |
5774 | kfree(name); | |
5775 | return err; | |
5776 | out_del_kobj: | |
5777 | kobject_del(&s->kobj); | |
54b6a731 | 5778 | goto out; |
81819f0f CL |
5779 | } |
5780 | ||
bf5eb3de | 5781 | static void sysfs_slab_remove(struct kmem_cache *s) |
81819f0f | 5782 | { |
97d06609 | 5783 | if (slab_state < FULL) |
2bce6485 CL |
5784 | /* |
5785 | * Sysfs has not been setup yet so no need to remove the | |
5786 | * cache from sysfs. | |
5787 | */ | |
5788 | return; | |
5789 | ||
3b7b3140 TH |
5790 | kobject_get(&s->kobj); |
5791 | schedule_work(&s->kobj_remove_work); | |
bf5eb3de TH |
5792 | } |
5793 | ||
d50d82fa MP |
5794 | void sysfs_slab_unlink(struct kmem_cache *s) |
5795 | { | |
5796 | if (slab_state >= FULL) | |
5797 | kobject_del(&s->kobj); | |
5798 | } | |
5799 | ||
bf5eb3de TH |
5800 | void sysfs_slab_release(struct kmem_cache *s) |
5801 | { | |
5802 | if (slab_state >= FULL) | |
5803 | kobject_put(&s->kobj); | |
81819f0f CL |
5804 | } |
5805 | ||
5806 | /* | |
5807 | * Need to buffer aliases during bootup until sysfs becomes | |
9f6c708e | 5808 | * available lest we lose that information. |
81819f0f CL |
5809 | */ |
5810 | struct saved_alias { | |
5811 | struct kmem_cache *s; | |
5812 | const char *name; | |
5813 | struct saved_alias *next; | |
5814 | }; | |
5815 | ||
5af328a5 | 5816 | static struct saved_alias *alias_list; |
81819f0f CL |
5817 | |
5818 | static int sysfs_slab_alias(struct kmem_cache *s, const char *name) | |
5819 | { | |
5820 | struct saved_alias *al; | |
5821 | ||
97d06609 | 5822 | if (slab_state == FULL) { |
81819f0f CL |
5823 | /* |
5824 | * If we have a leftover link then remove it. | |
5825 | */ | |
27c3a314 GKH |
5826 | sysfs_remove_link(&slab_kset->kobj, name); |
5827 | return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); | |
81819f0f CL |
5828 | } |
5829 | ||
5830 | al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); | |
5831 | if (!al) | |
5832 | return -ENOMEM; | |
5833 | ||
5834 | al->s = s; | |
5835 | al->name = name; | |
5836 | al->next = alias_list; | |
5837 | alias_list = al; | |
5838 | return 0; | |
5839 | } | |
5840 | ||
5841 | static int __init slab_sysfs_init(void) | |
5842 | { | |
5b95a4ac | 5843 | struct kmem_cache *s; |
81819f0f CL |
5844 | int err; |
5845 | ||
18004c5d | 5846 | mutex_lock(&slab_mutex); |
2bce6485 | 5847 | |
0ff21e46 | 5848 | slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj); |
27c3a314 | 5849 | if (!slab_kset) { |
18004c5d | 5850 | mutex_unlock(&slab_mutex); |
f9f58285 | 5851 | pr_err("Cannot register slab subsystem.\n"); |
81819f0f CL |
5852 | return -ENOSYS; |
5853 | } | |
5854 | ||
97d06609 | 5855 | slab_state = FULL; |
26a7bd03 | 5856 | |
5b95a4ac | 5857 | list_for_each_entry(s, &slab_caches, list) { |
26a7bd03 | 5858 | err = sysfs_slab_add(s); |
5d540fb7 | 5859 | if (err) |
f9f58285 FF |
5860 | pr_err("SLUB: Unable to add boot slab %s to sysfs\n", |
5861 | s->name); | |
26a7bd03 | 5862 | } |
81819f0f CL |
5863 | |
5864 | while (alias_list) { | |
5865 | struct saved_alias *al = alias_list; | |
5866 | ||
5867 | alias_list = alias_list->next; | |
5868 | err = sysfs_slab_alias(al->s, al->name); | |
5d540fb7 | 5869 | if (err) |
f9f58285 FF |
5870 | pr_err("SLUB: Unable to add boot slab alias %s to sysfs\n", |
5871 | al->name); | |
81819f0f CL |
5872 | kfree(al); |
5873 | } | |
5874 | ||
18004c5d | 5875 | mutex_unlock(&slab_mutex); |
81819f0f CL |
5876 | resiliency_test(); |
5877 | return 0; | |
5878 | } | |
5879 | ||
5880 | __initcall(slab_sysfs_init); | |
ab4d5ed5 | 5881 | #endif /* CONFIG_SYSFS */ |
57ed3eda PE |
5882 | |
5883 | /* | |
5884 | * The /proc/slabinfo ABI | |
5885 | */ | |
5b365771 | 5886 | #ifdef CONFIG_SLUB_DEBUG |
0d7561c6 | 5887 | void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) |
57ed3eda | 5888 | { |
57ed3eda | 5889 | unsigned long nr_slabs = 0; |
205ab99d CL |
5890 | unsigned long nr_objs = 0; |
5891 | unsigned long nr_free = 0; | |
57ed3eda | 5892 | int node; |
fa45dc25 | 5893 | struct kmem_cache_node *n; |
57ed3eda | 5894 | |
fa45dc25 | 5895 | for_each_kmem_cache_node(s, node, n) { |
c17fd13e WL |
5896 | nr_slabs += node_nr_slabs(n); |
5897 | nr_objs += node_nr_objs(n); | |
205ab99d | 5898 | nr_free += count_partial(n, count_free); |
57ed3eda PE |
5899 | } |
5900 | ||
0d7561c6 GC |
5901 | sinfo->active_objs = nr_objs - nr_free; |
5902 | sinfo->num_objs = nr_objs; | |
5903 | sinfo->active_slabs = nr_slabs; | |
5904 | sinfo->num_slabs = nr_slabs; | |
5905 | sinfo->objects_per_slab = oo_objects(s->oo); | |
5906 | sinfo->cache_order = oo_order(s->oo); | |
57ed3eda PE |
5907 | } |
5908 | ||
0d7561c6 | 5909 | void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s) |
7b3c3a50 | 5910 | { |
7b3c3a50 AD |
5911 | } |
5912 | ||
b7454ad3 GC |
5913 | ssize_t slabinfo_write(struct file *file, const char __user *buffer, |
5914 | size_t count, loff_t *ppos) | |
7b3c3a50 | 5915 | { |
b7454ad3 | 5916 | return -EIO; |
7b3c3a50 | 5917 | } |
5b365771 | 5918 | #endif /* CONFIG_SLUB_DEBUG */ |