Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
48c96a36 JK |
2 | #include <linux/debugfs.h> |
3 | #include <linux/mm.h> | |
4 | #include <linux/slab.h> | |
5 | #include <linux/uaccess.h> | |
57c8a661 | 6 | #include <linux/memblock.h> |
48c96a36 JK |
7 | #include <linux/stacktrace.h> |
8 | #include <linux/page_owner.h> | |
7dd80b8a | 9 | #include <linux/jump_label.h> |
7cd12b4a | 10 | #include <linux/migrate.h> |
f2ca0b55 | 11 | #include <linux/stackdepot.h> |
e2f612e6 | 12 | #include <linux/seq_file.h> |
fcf89358 | 13 | #include <linux/memcontrol.h> |
9cc7e96a | 14 | #include <linux/sched/clock.h> |
f2ca0b55 | 15 | |
48c96a36 JK |
16 | #include "internal.h" |
17 | ||
f2ca0b55 JK |
18 | /* |
19 | * TODO: teach PAGE_OWNER_STACK_DEPTH (__dump_page_owner and save_stack) | |
20 | * to use off stack temporal storage | |
21 | */ | |
22 | #define PAGE_OWNER_STACK_DEPTH (16) | |
23 | ||
9300d8df | 24 | struct page_owner { |
6b4c54e3 AM |
25 | unsigned short order; |
26 | short last_migrate_reason; | |
9300d8df | 27 | gfp_t gfp_mask; |
9300d8df | 28 | depot_stack_handle_t handle; |
8974558f | 29 | depot_stack_handle_t free_handle; |
9cc7e96a | 30 | u64 ts_nsec; |
866b4852 | 31 | u64 free_ts_nsec; |
865ed6a3 | 32 | char comm[TASK_COMM_LEN]; |
9cc7e96a | 33 | pid_t pid; |
bf215eab | 34 | pid_t tgid; |
1b5c65b6 BS |
35 | pid_t free_pid; |
36 | pid_t free_tgid; | |
9300d8df JK |
37 | }; |
38 | ||
4bedfb31 OS |
39 | struct stack { |
40 | struct stack_record *stack_record; | |
41 | struct stack *next; | |
42 | }; | |
43 | static struct stack dummy_stack; | |
44 | static struct stack failure_stack; | |
45 | static struct stack *stack_list; | |
217b2119 | 46 | static DEFINE_SPINLOCK(stack_list_lock); |
4bedfb31 | 47 | |
3645b5ec | 48 | static bool page_owner_enabled __initdata; |
7dd80b8a | 49 | DEFINE_STATIC_KEY_FALSE(page_owner_inited); |
48c96a36 | 50 | |
f2ca0b55 JK |
51 | static depot_stack_handle_t dummy_handle; |
52 | static depot_stack_handle_t failure_handle; | |
dab4ead1 | 53 | static depot_stack_handle_t early_handle; |
f2ca0b55 | 54 | |
61cf5feb JK |
55 | static void init_early_allocated_pages(void); |
56 | ||
1173194e | 57 | static int __init early_page_owner_param(char *buf) |
48c96a36 | 58 | { |
a5f1783b VB |
59 | int ret = kstrtobool(buf, &page_owner_enabled); |
60 | ||
61 | if (page_owner_enabled) | |
1c0310ad | 62 | stack_depot_request_early_init(); |
a5f1783b VB |
63 | |
64 | return ret; | |
48c96a36 JK |
65 | } |
66 | early_param("page_owner", early_page_owner_param); | |
67 | ||
cab0a7c1 | 68 | static __init bool need_page_owner(void) |
48c96a36 | 69 | { |
0fe9a448 | 70 | return page_owner_enabled; |
48c96a36 JK |
71 | } |
72 | ||
dab4ead1 | 73 | static __always_inline depot_stack_handle_t create_dummy_stack(void) |
f2ca0b55 JK |
74 | { |
75 | unsigned long entries[4]; | |
af52bf6b | 76 | unsigned int nr_entries; |
f2ca0b55 | 77 | |
af52bf6b TG |
78 | nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 0); |
79 | return stack_depot_save(entries, nr_entries, GFP_KERNEL); | |
f2ca0b55 JK |
80 | } |
81 | ||
dab4ead1 | 82 | static noinline void register_dummy_stack(void) |
f2ca0b55 | 83 | { |
dab4ead1 VB |
84 | dummy_handle = create_dummy_stack(); |
85 | } | |
f2ca0b55 | 86 | |
dab4ead1 VB |
87 | static noinline void register_failure_stack(void) |
88 | { | |
89 | failure_handle = create_dummy_stack(); | |
90 | } | |
f2ca0b55 | 91 | |
dab4ead1 VB |
92 | static noinline void register_early_stack(void) |
93 | { | |
94 | early_handle = create_dummy_stack(); | |
f2ca0b55 JK |
95 | } |
96 | ||
cab0a7c1 | 97 | static __init void init_page_owner(void) |
48c96a36 | 98 | { |
0fe9a448 | 99 | if (!page_owner_enabled) |
48c96a36 JK |
100 | return; |
101 | ||
f2ca0b55 JK |
102 | register_dummy_stack(); |
103 | register_failure_stack(); | |
dab4ead1 | 104 | register_early_stack(); |
7dd80b8a | 105 | static_branch_enable(&page_owner_inited); |
61cf5feb | 106 | init_early_allocated_pages(); |
4bedfb31 OS |
107 | /* Initialize dummy and failure stacks and link them to stack_list */ |
108 | dummy_stack.stack_record = __stack_depot_get_stack_record(dummy_handle); | |
109 | failure_stack.stack_record = __stack_depot_get_stack_record(failure_handle); | |
110 | refcount_set(&dummy_stack.stack_record->count, 1); | |
111 | refcount_set(&failure_stack.stack_record->count, 1); | |
112 | dummy_stack.next = &failure_stack; | |
113 | stack_list = &dummy_stack; | |
48c96a36 JK |
114 | } |
115 | ||
116 | struct page_ext_operations page_owner_ops = { | |
9300d8df | 117 | .size = sizeof(struct page_owner), |
48c96a36 JK |
118 | .need = need_page_owner, |
119 | .init = init_page_owner, | |
6189eb82 | 120 | .need_shared_flags = true, |
48c96a36 JK |
121 | }; |
122 | ||
9300d8df JK |
123 | static inline struct page_owner *get_page_owner(struct page_ext *page_ext) |
124 | { | |
1cac4c07 | 125 | return page_ext_data(page_ext, &page_owner_ops); |
9300d8df JK |
126 | } |
127 | ||
f2ca0b55 JK |
128 | static noinline depot_stack_handle_t save_stack(gfp_t flags) |
129 | { | |
130 | unsigned long entries[PAGE_OWNER_STACK_DEPTH]; | |
f2ca0b55 | 131 | depot_stack_handle_t handle; |
af52bf6b | 132 | unsigned int nr_entries; |
f2ca0b55 | 133 | |
f2ca0b55 | 134 | /* |
8e9b16c4 ST |
135 | * Avoid recursion. |
136 | * | |
137 | * Sometimes page metadata allocation tracking requires more | |
138 | * memory to be allocated: | |
139 | * - when new stack trace is saved to stack depot | |
f2ca0b55 | 140 | */ |
8e9b16c4 | 141 | if (current->in_page_owner) |
f2ca0b55 | 142 | return dummy_handle; |
8e9b16c4 | 143 | current->in_page_owner = 1; |
f2ca0b55 | 144 | |
8e9b16c4 | 145 | nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 2); |
af52bf6b | 146 | handle = stack_depot_save(entries, nr_entries, flags); |
f2ca0b55 JK |
147 | if (!handle) |
148 | handle = failure_handle; | |
149 | ||
8e9b16c4 | 150 | current->in_page_owner = 0; |
f2ca0b55 JK |
151 | return handle; |
152 | } | |
153 | ||
217b2119 OS |
154 | static void add_stack_record_to_list(struct stack_record *stack_record, |
155 | gfp_t gfp_mask) | |
156 | { | |
157 | unsigned long flags; | |
158 | struct stack *stack; | |
159 | ||
160 | /* Filter gfp_mask the same way stackdepot does, for consistency */ | |
161 | gfp_mask &= ~GFP_ZONEMASK; | |
162 | gfp_mask &= (GFP_ATOMIC | GFP_KERNEL); | |
163 | gfp_mask |= __GFP_NOWARN; | |
164 | ||
165 | stack = kmalloc(sizeof(*stack), gfp_mask); | |
166 | if (!stack) | |
167 | return; | |
168 | ||
169 | stack->stack_record = stack_record; | |
170 | stack->next = NULL; | |
171 | ||
172 | spin_lock_irqsave(&stack_list_lock, flags); | |
173 | stack->next = stack_list; | |
174 | stack_list = stack; | |
175 | spin_unlock_irqrestore(&stack_list_lock, flags); | |
176 | } | |
177 | ||
178 | static void inc_stack_record_count(depot_stack_handle_t handle, gfp_t gfp_mask) | |
179 | { | |
180 | struct stack_record *stack_record = __stack_depot_get_stack_record(handle); | |
181 | ||
182 | if (!stack_record) | |
183 | return; | |
184 | ||
185 | /* | |
186 | * New stack_record's that do not use STACK_DEPOT_FLAG_GET start | |
187 | * with REFCOUNT_SATURATED to catch spurious increments of their | |
188 | * refcount. | |
189 | * Since we do not use STACK_DEPOT_FLAG_GET API, let us | |
190 | * set a refcount of 1 ourselves. | |
191 | */ | |
192 | if (refcount_read(&stack_record->count) == REFCOUNT_SATURATED) { | |
193 | int old = REFCOUNT_SATURATED; | |
194 | ||
195 | if (atomic_try_cmpxchg_relaxed(&stack_record->count.refs, &old, 1)) | |
196 | /* Add the new stack_record to our list */ | |
197 | add_stack_record_to_list(stack_record, gfp_mask); | |
198 | } | |
199 | refcount_inc(&stack_record->count); | |
200 | } | |
201 | ||
202 | static void dec_stack_record_count(depot_stack_handle_t handle) | |
203 | { | |
204 | struct stack_record *stack_record = __stack_depot_get_stack_record(handle); | |
205 | ||
206 | if (stack_record) | |
207 | refcount_dec(&stack_record->count); | |
208 | } | |
209 | ||
0093de69 | 210 | void __reset_page_owner(struct page *page, unsigned short order) |
8974558f VB |
211 | { |
212 | int i; | |
213 | struct page_ext *page_ext; | |
fab765c2 | 214 | depot_stack_handle_t handle; |
217b2119 | 215 | depot_stack_handle_t alloc_handle; |
8974558f | 216 | struct page_owner *page_owner; |
866b4852 | 217 | u64 free_ts_nsec = local_clock(); |
8974558f | 218 | |
b1d5488a | 219 | page_ext = page_ext_get(page); |
5556cfe8 VB |
220 | if (unlikely(!page_ext)) |
221 | return; | |
fab765c2 | 222 | |
217b2119 OS |
223 | page_owner = get_page_owner(page_ext); |
224 | alloc_handle = page_owner->handle; | |
225 | ||
fab765c2 | 226 | handle = save_stack(GFP_NOWAIT | __GFP_NOWARN); |
8974558f | 227 | for (i = 0; i < (1 << order); i++) { |
fdf3bf80 | 228 | __clear_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags); |
0fe9a448 | 229 | page_owner->free_handle = handle; |
866b4852 | 230 | page_owner->free_ts_nsec = free_ts_nsec; |
1b5c65b6 BS |
231 | page_owner->free_pid = current->pid; |
232 | page_owner->free_tgid = current->tgid; | |
5556cfe8 | 233 | page_ext = page_ext_next(page_ext); |
217b2119 | 234 | page_owner = get_page_owner(page_ext); |
8974558f | 235 | } |
b1d5488a | 236 | page_ext_put(page_ext); |
217b2119 OS |
237 | if (alloc_handle != early_handle) |
238 | /* | |
239 | * early_handle is being set as a handle for all those | |
240 | * early allocated pages. See init_pages_in_zone(). | |
241 | * Since their refcount is not being incremented because | |
242 | * the machinery is not ready yet, we cannot decrement | |
243 | * their refcount either. | |
244 | */ | |
245 | dec_stack_record_count(alloc_handle); | |
8974558f VB |
246 | } |
247 | ||
64ea78d2 | 248 | static inline void __set_page_owner_handle(struct page_ext *page_ext, |
249 | depot_stack_handle_t handle, | |
0093de69 | 250 | unsigned short order, gfp_t gfp_mask) |
f2ca0b55 | 251 | { |
9300d8df | 252 | struct page_owner *page_owner; |
7e2f2a0c | 253 | int i; |
05a42199 | 254 | u64 ts_nsec = local_clock(); |
48c96a36 | 255 | |
7e2f2a0c VB |
256 | for (i = 0; i < (1 << order); i++) { |
257 | page_owner = get_page_owner(page_ext); | |
258 | page_owner->handle = handle; | |
259 | page_owner->order = order; | |
260 | page_owner->gfp_mask = gfp_mask; | |
261 | page_owner->last_migrate_reason = -1; | |
9cc7e96a | 262 | page_owner->pid = current->pid; |
bf215eab | 263 | page_owner->tgid = current->tgid; |
05a42199 | 264 | page_owner->ts_nsec = ts_nsec; |
cd8c1fd8 | 265 | strscpy(page_owner->comm, current->comm, |
865ed6a3 | 266 | sizeof(page_owner->comm)); |
7e2f2a0c | 267 | __set_bit(PAGE_EXT_OWNER, &page_ext->flags); |
fdf3bf80 | 268 | __set_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags); |
48c96a36 | 269 | |
5556cfe8 | 270 | page_ext = page_ext_next(page_ext); |
7e2f2a0c | 271 | } |
48c96a36 JK |
272 | } |
273 | ||
0093de69 | 274 | noinline void __set_page_owner(struct page *page, unsigned short order, |
dab4ead1 VB |
275 | gfp_t gfp_mask) |
276 | { | |
b1d5488a | 277 | struct page_ext *page_ext; |
dab4ead1 VB |
278 | depot_stack_handle_t handle; |
279 | ||
b1d5488a CTK |
280 | handle = save_stack(gfp_mask); |
281 | ||
282 | page_ext = page_ext_get(page); | |
dab4ead1 VB |
283 | if (unlikely(!page_ext)) |
284 | return; | |
64ea78d2 | 285 | __set_page_owner_handle(page_ext, handle, order, gfp_mask); |
b1d5488a | 286 | page_ext_put(page_ext); |
217b2119 | 287 | inc_stack_record_count(handle, gfp_mask); |
dab4ead1 VB |
288 | } |
289 | ||
7cd12b4a VB |
290 | void __set_page_owner_migrate_reason(struct page *page, int reason) |
291 | { | |
b1d5488a | 292 | struct page_ext *page_ext = page_ext_get(page); |
9300d8df JK |
293 | struct page_owner *page_owner; |
294 | ||
f86e4271 YS |
295 | if (unlikely(!page_ext)) |
296 | return; | |
7cd12b4a | 297 | |
9300d8df JK |
298 | page_owner = get_page_owner(page_ext); |
299 | page_owner->last_migrate_reason = reason; | |
b1d5488a | 300 | page_ext_put(page_ext); |
7cd12b4a VB |
301 | } |
302 | ||
8fb156c9 | 303 | void __split_page_owner(struct page *page, unsigned int nr) |
e2cfc911 | 304 | { |
a9627bc5 | 305 | int i; |
b1d5488a | 306 | struct page_ext *page_ext = page_ext_get(page); |
9300d8df | 307 | struct page_owner *page_owner; |
a9627bc5 | 308 | |
f86e4271 | 309 | if (unlikely(!page_ext)) |
a9627bc5 | 310 | return; |
e2cfc911 | 311 | |
8fb156c9 | 312 | for (i = 0; i < nr; i++) { |
7e2f2a0c VB |
313 | page_owner = get_page_owner(page_ext); |
314 | page_owner->order = 0; | |
5556cfe8 | 315 | page_ext = page_ext_next(page_ext); |
7e2f2a0c | 316 | } |
b1d5488a | 317 | page_ext_put(page_ext); |
e2cfc911 JK |
318 | } |
319 | ||
19138349 | 320 | void __folio_copy_owner(struct folio *newfolio, struct folio *old) |
d435edca | 321 | { |
b1d5488a CTK |
322 | struct page_ext *old_ext; |
323 | struct page_ext *new_ext; | |
9300d8df | 324 | struct page_owner *old_page_owner, *new_page_owner; |
d435edca | 325 | |
b1d5488a CTK |
326 | old_ext = page_ext_get(&old->page); |
327 | if (unlikely(!old_ext)) | |
f86e4271 YS |
328 | return; |
329 | ||
b1d5488a CTK |
330 | new_ext = page_ext_get(&newfolio->page); |
331 | if (unlikely(!new_ext)) { | |
332 | page_ext_put(old_ext); | |
333 | return; | |
334 | } | |
335 | ||
9300d8df JK |
336 | old_page_owner = get_page_owner(old_ext); |
337 | new_page_owner = get_page_owner(new_ext); | |
338 | new_page_owner->order = old_page_owner->order; | |
339 | new_page_owner->gfp_mask = old_page_owner->gfp_mask; | |
340 | new_page_owner->last_migrate_reason = | |
341 | old_page_owner->last_migrate_reason; | |
342 | new_page_owner->handle = old_page_owner->handle; | |
9cc7e96a | 343 | new_page_owner->pid = old_page_owner->pid; |
bf215eab | 344 | new_page_owner->tgid = old_page_owner->tgid; |
1b5c65b6 BS |
345 | new_page_owner->free_pid = old_page_owner->free_pid; |
346 | new_page_owner->free_tgid = old_page_owner->free_tgid; | |
9cc7e96a | 347 | new_page_owner->ts_nsec = old_page_owner->ts_nsec; |
866b4852 | 348 | new_page_owner->free_ts_nsec = old_page_owner->ts_nsec; |
865ed6a3 | 349 | strcpy(new_page_owner->comm, old_page_owner->comm); |
d435edca VB |
350 | |
351 | /* | |
19138349 | 352 | * We don't clear the bit on the old folio as it's going to be freed |
d435edca | 353 | * after migration. Until then, the info can be useful in case of |
f0953a1b | 354 | * a bug, and the overall stats will be off a bit only temporarily. |
d435edca | 355 | * Also, migrate_misplaced_transhuge_page() can still fail the |
19138349 | 356 | * migration and then we want the old folio to retain the info. But |
d435edca VB |
357 | * in that case we also don't need to explicitly clear the info from |
358 | * the new page, which will be freed. | |
359 | */ | |
360 | __set_bit(PAGE_EXT_OWNER, &new_ext->flags); | |
fdf3bf80 | 361 | __set_bit(PAGE_EXT_OWNER_ALLOCATED, &new_ext->flags); |
b1d5488a CTK |
362 | page_ext_put(new_ext); |
363 | page_ext_put(old_ext); | |
d435edca VB |
364 | } |
365 | ||
e2f612e6 JK |
366 | void pagetypeinfo_showmixedcount_print(struct seq_file *m, |
367 | pg_data_t *pgdat, struct zone *zone) | |
368 | { | |
369 | struct page *page; | |
370 | struct page_ext *page_ext; | |
9300d8df | 371 | struct page_owner *page_owner; |
1d2cae8e ML |
372 | unsigned long pfn, block_end_pfn; |
373 | unsigned long end_pfn = zone_end_pfn(zone); | |
e2f612e6 JK |
374 | unsigned long count[MIGRATE_TYPES] = { 0, }; |
375 | int pageblock_mt, page_mt; | |
376 | int i; | |
377 | ||
378 | /* Scan block by block. First and last block may be incomplete */ | |
379 | pfn = zone->zone_start_pfn; | |
380 | ||
381 | /* | |
382 | * Walk the zone in pageblock_nr_pages steps. If a page block spans | |
383 | * a zone boundary, it will be double counted between zones. This does | |
384 | * not matter as the mixed block count will still be correct | |
385 | */ | |
386 | for (; pfn < end_pfn; ) { | |
a26ee565 QC |
387 | page = pfn_to_online_page(pfn); |
388 | if (!page) { | |
e2f612e6 JK |
389 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES); |
390 | continue; | |
391 | } | |
392 | ||
4f9bc69a | 393 | block_end_pfn = pageblock_end_pfn(pfn); |
e2f612e6 JK |
394 | block_end_pfn = min(block_end_pfn, end_pfn); |
395 | ||
e2f612e6 JK |
396 | pageblock_mt = get_pageblock_migratetype(page); |
397 | ||
398 | for (; pfn < block_end_pfn; pfn++) { | |
a26ee565 | 399 | /* The pageblock is online, no need to recheck. */ |
e2f612e6 JK |
400 | page = pfn_to_page(pfn); |
401 | ||
402 | if (page_zone(page) != zone) | |
403 | continue; | |
404 | ||
405 | if (PageBuddy(page)) { | |
727c080f VM |
406 | unsigned long freepage_order; |
407 | ||
ab130f91 | 408 | freepage_order = buddy_order_unsafe(page); |
5e0a760b | 409 | if (freepage_order <= MAX_PAGE_ORDER) |
727c080f | 410 | pfn += (1UL << freepage_order) - 1; |
e2f612e6 JK |
411 | continue; |
412 | } | |
413 | ||
414 | if (PageReserved(page)) | |
415 | continue; | |
416 | ||
b1d5488a | 417 | page_ext = page_ext_get(page); |
e2f612e6 JK |
418 | if (unlikely(!page_ext)) |
419 | continue; | |
420 | ||
fdf3bf80 | 421 | if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) |
b1d5488a | 422 | goto ext_put_continue; |
e2f612e6 | 423 | |
9300d8df | 424 | page_owner = get_page_owner(page_ext); |
01c0bfe0 | 425 | page_mt = gfp_migratetype(page_owner->gfp_mask); |
e2f612e6 JK |
426 | if (pageblock_mt != page_mt) { |
427 | if (is_migrate_cma(pageblock_mt)) | |
428 | count[MIGRATE_MOVABLE]++; | |
429 | else | |
430 | count[pageblock_mt]++; | |
431 | ||
432 | pfn = block_end_pfn; | |
b1d5488a | 433 | page_ext_put(page_ext); |
e2f612e6 JK |
434 | break; |
435 | } | |
9300d8df | 436 | pfn += (1UL << page_owner->order) - 1; |
b1d5488a CTK |
437 | ext_put_continue: |
438 | page_ext_put(page_ext); | |
e2f612e6 JK |
439 | } |
440 | } | |
441 | ||
442 | /* Print counts */ | |
443 | seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); | |
444 | for (i = 0; i < MIGRATE_TYPES; i++) | |
445 | seq_printf(m, "%12lu ", count[i]); | |
446 | seq_putc(m, '\n'); | |
447 | } | |
448 | ||
fcf89358 WL |
449 | /* |
450 | * Looking for memcg information and print it out | |
451 | */ | |
452 | static inline int print_page_owner_memcg(char *kbuf, size_t count, int ret, | |
453 | struct page *page) | |
454 | { | |
455 | #ifdef CONFIG_MEMCG | |
456 | unsigned long memcg_data; | |
457 | struct mem_cgroup *memcg; | |
458 | bool online; | |
459 | char name[80]; | |
460 | ||
461 | rcu_read_lock(); | |
462 | memcg_data = READ_ONCE(page->memcg_data); | |
463 | if (!memcg_data) | |
464 | goto out_unlock; | |
465 | ||
466 | if (memcg_data & MEMCG_DATA_OBJCGS) | |
467 | ret += scnprintf(kbuf + ret, count - ret, | |
468 | "Slab cache page\n"); | |
469 | ||
470 | memcg = page_memcg_check(page); | |
471 | if (!memcg) | |
472 | goto out_unlock; | |
473 | ||
474 | online = (memcg->css.flags & CSS_ONLINE); | |
475 | cgroup_name(memcg->css.cgroup, name, sizeof(name)); | |
476 | ret += scnprintf(kbuf + ret, count - ret, | |
477 | "Charged %sto %smemcg %s\n", | |
478 | PageMemcgKmem(page) ? "(via objcg) " : "", | |
479 | online ? "" : "offline ", | |
480 | name); | |
481 | out_unlock: | |
482 | rcu_read_unlock(); | |
483 | #endif /* CONFIG_MEMCG */ | |
484 | ||
485 | return ret; | |
486 | } | |
487 | ||
48c96a36 JK |
488 | static ssize_t |
489 | print_page_owner(char __user *buf, size_t count, unsigned long pfn, | |
9300d8df | 490 | struct page *page, struct page_owner *page_owner, |
f2ca0b55 | 491 | depot_stack_handle_t handle) |
48c96a36 | 492 | { |
af52bf6b | 493 | int ret, pageblock_mt, page_mt; |
48c96a36 JK |
494 | char *kbuf; |
495 | ||
c8f61cfc | 496 | count = min_t(size_t, count, PAGE_SIZE); |
48c96a36 JK |
497 | kbuf = kmalloc(count, GFP_KERNEL); |
498 | if (!kbuf) | |
499 | return -ENOMEM; | |
500 | ||
3ebc4397 | 501 | ret = scnprintf(kbuf, count, |
b459f090 | 502 | "Page allocated via order %u, mask %#x(%pGg), pid %d, tgid %d (%s), ts %llu ns\n", |
9300d8df | 503 | page_owner->order, page_owner->gfp_mask, |
9cc7e96a | 504 | &page_owner->gfp_mask, page_owner->pid, |
bf215eab | 505 | page_owner->tgid, page_owner->comm, |
b459f090 | 506 | page_owner->ts_nsec); |
48c96a36 | 507 | |
48c96a36 | 508 | /* Print information relevant to grouping pages by mobility */ |
0b423ca2 | 509 | pageblock_mt = get_pageblock_migratetype(page); |
01c0bfe0 | 510 | page_mt = gfp_migratetype(page_owner->gfp_mask); |
3ebc4397 | 511 | ret += scnprintf(kbuf + ret, count - ret, |
399fd496 | 512 | "PFN 0x%lx type %s Block %lu type %s Flags %pGp\n", |
48c96a36 | 513 | pfn, |
60f30350 | 514 | migratetype_names[page_mt], |
48c96a36 | 515 | pfn >> pageblock_order, |
60f30350 | 516 | migratetype_names[pageblock_mt], |
23efd080 | 517 | &page->flags); |
48c96a36 | 518 | |
0f68d45e | 519 | ret += stack_depot_snprint(handle, kbuf + ret, count - ret, 0); |
48c96a36 JK |
520 | if (ret >= count) |
521 | goto err; | |
522 | ||
9300d8df | 523 | if (page_owner->last_migrate_reason != -1) { |
3ebc4397 | 524 | ret += scnprintf(kbuf + ret, count - ret, |
7cd12b4a | 525 | "Page has been migrated, last migrate reason: %s\n", |
9300d8df | 526 | migrate_reason_names[page_owner->last_migrate_reason]); |
7cd12b4a VB |
527 | } |
528 | ||
fcf89358 WL |
529 | ret = print_page_owner_memcg(kbuf, count, ret, page); |
530 | ||
48c96a36 JK |
531 | ret += snprintf(kbuf + ret, count - ret, "\n"); |
532 | if (ret >= count) | |
533 | goto err; | |
534 | ||
535 | if (copy_to_user(buf, kbuf, ret)) | |
536 | ret = -EFAULT; | |
537 | ||
538 | kfree(kbuf); | |
539 | return ret; | |
540 | ||
541 | err: | |
542 | kfree(kbuf); | |
543 | return -ENOMEM; | |
544 | } | |
545 | ||
8bf6f451 | 546 | void __dump_page_owner(const struct page *page) |
4e462112 | 547 | { |
b1d5488a | 548 | struct page_ext *page_ext = page_ext_get((void *)page); |
9300d8df | 549 | struct page_owner *page_owner; |
f2ca0b55 | 550 | depot_stack_handle_t handle; |
8285027f SM |
551 | gfp_t gfp_mask; |
552 | int mt; | |
4e462112 | 553 | |
f86e4271 YS |
554 | if (unlikely(!page_ext)) { |
555 | pr_alert("There is not page extension available.\n"); | |
556 | return; | |
557 | } | |
9300d8df JK |
558 | |
559 | page_owner = get_page_owner(page_ext); | |
560 | gfp_mask = page_owner->gfp_mask; | |
01c0bfe0 | 561 | mt = gfp_migratetype(gfp_mask); |
f86e4271 | 562 | |
4e462112 | 563 | if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags)) { |
37389167 | 564 | pr_alert("page_owner info is not present (never set?)\n"); |
b1d5488a | 565 | page_ext_put(page_ext); |
4e462112 VB |
566 | return; |
567 | } | |
568 | ||
fdf3bf80 | 569 | if (test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) |
37389167 VB |
570 | pr_alert("page_owner tracks the page as allocated\n"); |
571 | else | |
572 | pr_alert("page_owner tracks the page as freed\n"); | |
573 | ||
bf215eab | 574 | pr_alert("page last allocated via order %u, migratetype %s, gfp_mask %#x(%pGg), pid %d, tgid %d (%s), ts %llu, free_ts %llu\n", |
9cc7e96a | 575 | page_owner->order, migratetype_names[mt], gfp_mask, &gfp_mask, |
bf215eab YC |
576 | page_owner->pid, page_owner->tgid, page_owner->comm, |
577 | page_owner->ts_nsec, page_owner->free_ts_nsec); | |
37389167 | 578 | |
9300d8df | 579 | handle = READ_ONCE(page_owner->handle); |
505be481 | 580 | if (!handle) |
37389167 | 581 | pr_alert("page_owner allocation stack trace missing\n"); |
505be481 IK |
582 | else |
583 | stack_depot_print(handle); | |
f2ca0b55 | 584 | |
8974558f VB |
585 | handle = READ_ONCE(page_owner->free_handle); |
586 | if (!handle) { | |
587 | pr_alert("page_owner free stack trace missing\n"); | |
588 | } else { | |
1b5c65b6 BS |
589 | pr_alert("page last free pid %d tgid %d stack trace:\n", |
590 | page_owner->free_pid, page_owner->free_tgid); | |
505be481 | 591 | stack_depot_print(handle); |
8974558f | 592 | } |
8974558f | 593 | |
9300d8df | 594 | if (page_owner->last_migrate_reason != -1) |
4e462112 | 595 | pr_alert("page has been migrated, last migrate reason: %s\n", |
9300d8df | 596 | migrate_reason_names[page_owner->last_migrate_reason]); |
b1d5488a | 597 | page_ext_put(page_ext); |
4e462112 VB |
598 | } |
599 | ||
48c96a36 JK |
600 | static ssize_t |
601 | read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
602 | { | |
603 | unsigned long pfn; | |
604 | struct page *page; | |
605 | struct page_ext *page_ext; | |
9300d8df | 606 | struct page_owner *page_owner; |
f2ca0b55 | 607 | depot_stack_handle_t handle; |
48c96a36 | 608 | |
7dd80b8a | 609 | if (!static_branch_unlikely(&page_owner_inited)) |
48c96a36 JK |
610 | return -EINVAL; |
611 | ||
612 | page = NULL; | |
8f0efa81 KL |
613 | if (*ppos == 0) |
614 | pfn = min_low_pfn; | |
615 | else | |
616 | pfn = *ppos; | |
48c96a36 JK |
617 | /* Find a valid PFN or the start of a MAX_ORDER_NR_PAGES area */ |
618 | while (!pfn_valid(pfn) && (pfn & (MAX_ORDER_NR_PAGES - 1)) != 0) | |
619 | pfn++; | |
620 | ||
48c96a36 JK |
621 | /* Find an allocated page */ |
622 | for (; pfn < max_pfn; pfn++) { | |
b1d5488a CTK |
623 | /* |
624 | * This temporary page_owner is required so | |
625 | * that we can avoid the context switches while holding | |
626 | * the rcu lock and copying the page owner information to | |
627 | * user through copy_to_user() or GFP_KERNEL allocations. | |
628 | */ | |
629 | struct page_owner page_owner_tmp; | |
630 | ||
48c96a36 JK |
631 | /* |
632 | * If the new page is in a new MAX_ORDER_NR_PAGES area, | |
633 | * validate the area as existing, skip it if not | |
634 | */ | |
635 | if ((pfn & (MAX_ORDER_NR_PAGES - 1)) == 0 && !pfn_valid(pfn)) { | |
636 | pfn += MAX_ORDER_NR_PAGES - 1; | |
637 | continue; | |
638 | } | |
639 | ||
48c96a36 JK |
640 | page = pfn_to_page(pfn); |
641 | if (PageBuddy(page)) { | |
ab130f91 | 642 | unsigned long freepage_order = buddy_order_unsafe(page); |
48c96a36 | 643 | |
5e0a760b | 644 | if (freepage_order <= MAX_PAGE_ORDER) |
48c96a36 JK |
645 | pfn += (1UL << freepage_order) - 1; |
646 | continue; | |
647 | } | |
648 | ||
b1d5488a | 649 | page_ext = page_ext_get(page); |
f86e4271 YS |
650 | if (unlikely(!page_ext)) |
651 | continue; | |
48c96a36 JK |
652 | |
653 | /* | |
61cf5feb JK |
654 | * Some pages could be missed by concurrent allocation or free, |
655 | * because we don't hold the zone lock. | |
48c96a36 JK |
656 | */ |
657 | if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags)) | |
b1d5488a | 658 | goto ext_put_continue; |
48c96a36 | 659 | |
37389167 VB |
660 | /* |
661 | * Although we do have the info about past allocation of free | |
662 | * pages, it's not relevant for current memory usage. | |
663 | */ | |
fdf3bf80 | 664 | if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) |
b1d5488a | 665 | goto ext_put_continue; |
37389167 | 666 | |
9300d8df JK |
667 | page_owner = get_page_owner(page_ext); |
668 | ||
7e2f2a0c VB |
669 | /* |
670 | * Don't print "tail" pages of high-order allocations as that | |
671 | * would inflate the stats. | |
672 | */ | |
673 | if (!IS_ALIGNED(pfn, 1 << page_owner->order)) | |
b1d5488a | 674 | goto ext_put_continue; |
7e2f2a0c | 675 | |
f2ca0b55 JK |
676 | /* |
677 | * Access to page_ext->handle isn't synchronous so we should | |
678 | * be careful to access it. | |
679 | */ | |
9300d8df | 680 | handle = READ_ONCE(page_owner->handle); |
f2ca0b55 | 681 | if (!handle) |
b1d5488a | 682 | goto ext_put_continue; |
f2ca0b55 | 683 | |
48c96a36 | 684 | /* Record the next PFN to read in the file offset */ |
8f0efa81 | 685 | *ppos = pfn + 1; |
48c96a36 | 686 | |
b1d5488a CTK |
687 | page_owner_tmp = *page_owner; |
688 | page_ext_put(page_ext); | |
f2ca0b55 | 689 | return print_page_owner(buf, count, pfn, page, |
b1d5488a CTK |
690 | &page_owner_tmp, handle); |
691 | ext_put_continue: | |
692 | page_ext_put(page_ext); | |
48c96a36 JK |
693 | } |
694 | ||
695 | return 0; | |
696 | } | |
697 | ||
8f0efa81 KL |
698 | static loff_t lseek_page_owner(struct file *file, loff_t offset, int orig) |
699 | { | |
700 | switch (orig) { | |
701 | case SEEK_SET: | |
702 | file->f_pos = offset; | |
703 | break; | |
704 | case SEEK_CUR: | |
705 | file->f_pos += offset; | |
706 | break; | |
707 | default: | |
708 | return -EINVAL; | |
709 | } | |
710 | return file->f_pos; | |
711 | } | |
712 | ||
61cf5feb JK |
713 | static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone) |
714 | { | |
6787c1da OS |
715 | unsigned long pfn = zone->zone_start_pfn; |
716 | unsigned long end_pfn = zone_end_pfn(zone); | |
61cf5feb JK |
717 | unsigned long count = 0; |
718 | ||
61cf5feb JK |
719 | /* |
720 | * Walk the zone in pageblock_nr_pages steps. If a page block spans | |
721 | * a zone boundary, it will be double counted between zones. This does | |
722 | * not matter as the mixed block count will still be correct | |
723 | */ | |
724 | for (; pfn < end_pfn; ) { | |
6787c1da OS |
725 | unsigned long block_end_pfn; |
726 | ||
61cf5feb JK |
727 | if (!pfn_valid(pfn)) { |
728 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES); | |
729 | continue; | |
730 | } | |
731 | ||
4f9bc69a | 732 | block_end_pfn = pageblock_end_pfn(pfn); |
61cf5feb JK |
733 | block_end_pfn = min(block_end_pfn, end_pfn); |
734 | ||
61cf5feb | 735 | for (; pfn < block_end_pfn; pfn++) { |
859a85dd | 736 | struct page *page = pfn_to_page(pfn); |
6787c1da OS |
737 | struct page_ext *page_ext; |
738 | ||
9d43f5ae JK |
739 | if (page_zone(page) != zone) |
740 | continue; | |
741 | ||
61cf5feb | 742 | /* |
10903027 VB |
743 | * To avoid having to grab zone->lock, be a little |
744 | * careful when reading buddy page order. The only | |
745 | * danger is that we skip too much and potentially miss | |
746 | * some early allocated pages, which is better than | |
747 | * heavy lock contention. | |
61cf5feb JK |
748 | */ |
749 | if (PageBuddy(page)) { | |
ab130f91 | 750 | unsigned long order = buddy_order_unsafe(page); |
10903027 | 751 | |
5e0a760b | 752 | if (order > 0 && order <= MAX_PAGE_ORDER) |
10903027 | 753 | pfn += (1UL << order) - 1; |
61cf5feb JK |
754 | continue; |
755 | } | |
756 | ||
757 | if (PageReserved(page)) | |
758 | continue; | |
759 | ||
b1d5488a | 760 | page_ext = page_ext_get(page); |
f86e4271 YS |
761 | if (unlikely(!page_ext)) |
762 | continue; | |
61cf5feb | 763 | |
dab4ead1 | 764 | /* Maybe overlapping zone */ |
61cf5feb | 765 | if (test_bit(PAGE_EXT_OWNER, &page_ext->flags)) |
b1d5488a | 766 | goto ext_put_continue; |
61cf5feb JK |
767 | |
768 | /* Found early allocated page */ | |
64ea78d2 | 769 | __set_page_owner_handle(page_ext, early_handle, |
7e2f2a0c | 770 | 0, 0); |
61cf5feb | 771 | count++; |
b1d5488a CTK |
772 | ext_put_continue: |
773 | page_ext_put(page_ext); | |
61cf5feb | 774 | } |
10903027 | 775 | cond_resched(); |
61cf5feb JK |
776 | } |
777 | ||
778 | pr_info("Node %d, zone %8s: page owner found early allocated %lu pages\n", | |
779 | pgdat->node_id, zone->name, count); | |
780 | } | |
781 | ||
782 | static void init_zones_in_node(pg_data_t *pgdat) | |
783 | { | |
784 | struct zone *zone; | |
785 | struct zone *node_zones = pgdat->node_zones; | |
61cf5feb JK |
786 | |
787 | for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) { | |
788 | if (!populated_zone(zone)) | |
789 | continue; | |
790 | ||
61cf5feb | 791 | init_pages_in_zone(pgdat, zone); |
61cf5feb JK |
792 | } |
793 | } | |
794 | ||
795 | static void init_early_allocated_pages(void) | |
796 | { | |
797 | pg_data_t *pgdat; | |
798 | ||
61cf5feb JK |
799 | for_each_online_pgdat(pgdat) |
800 | init_zones_in_node(pgdat); | |
801 | } | |
802 | ||
48c96a36 JK |
803 | static const struct file_operations proc_page_owner_operations = { |
804 | .read = read_page_owner, | |
8f0efa81 | 805 | .llseek = lseek_page_owner, |
48c96a36 JK |
806 | }; |
807 | ||
808 | static int __init pageowner_init(void) | |
809 | { | |
7dd80b8a | 810 | if (!static_branch_unlikely(&page_owner_inited)) { |
48c96a36 JK |
811 | pr_info("page_owner is disabled\n"); |
812 | return 0; | |
813 | } | |
814 | ||
d9f7979c GKH |
815 | debugfs_create_file("page_owner", 0400, NULL, NULL, |
816 | &proc_page_owner_operations); | |
48c96a36 | 817 | |
d9f7979c | 818 | return 0; |
48c96a36 | 819 | } |
44c5af96 | 820 | late_initcall(pageowner_init) |