1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/alloc_tag.h>
3 #include <linux/execmem.h>
4 #include <linux/fs.h>
5 #include <linux/gfp.h>
6 #include <linux/kallsyms.h>
7 #include <linux/module.h>
8 #include <linux/page_ext.h>
9 #include <linux/proc_fs.h>
10 #include <linux/seq_buf.h>
11 #include <linux/seq_file.h>
12 #include <linux/vmalloc.h>
13
14 #define ALLOCINFO_FILE_NAME "allocinfo"
15 #define MODULE_ALLOC_TAG_VMAP_SIZE (100000UL * sizeof(struct alloc_tag))
16 #define SECTION_START(NAME) (CODETAG_SECTION_START_PREFIX NAME)
17 #define SECTION_STOP(NAME) (CODETAG_SECTION_STOP_PREFIX NAME)
18
19 #ifdef CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT
20 static bool mem_profiling_support = true;
21 #else
22 static bool mem_profiling_support;
23 #endif
24
25 static struct codetag_type *alloc_tag_cttype;
26
27 DEFINE_PER_CPU(struct alloc_tag_counters, _shared_alloc_tag);
28 EXPORT_SYMBOL(_shared_alloc_tag);
29
30 DEFINE_STATIC_KEY_MAYBE(CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT,
31 mem_alloc_profiling_key);
32 EXPORT_SYMBOL(mem_alloc_profiling_key);
33
34 DEFINE_STATIC_KEY_FALSE(mem_profiling_compressed);
35
36 struct alloc_tag_kernel_section kernel_tags = { NULL, 0 };
37 unsigned long alloc_tag_ref_mask;
38 int alloc_tag_ref_offs;
39
40 struct allocinfo_private {
41 struct codetag_iterator iter;
42 bool print_header;
43 };
44
allocinfo_start(struct seq_file * m,loff_t * pos)45 static void *allocinfo_start(struct seq_file *m, loff_t *pos)
46 {
47 struct allocinfo_private *priv;
48 struct codetag *ct;
49 loff_t node = *pos;
50
51 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
52 m->private = priv;
53 if (!priv)
54 return NULL;
55
56 priv->print_header = (node == 0);
57 codetag_lock_module_list(alloc_tag_cttype, true);
58 priv->iter = codetag_get_ct_iter(alloc_tag_cttype);
59 while ((ct = codetag_next_ct(&priv->iter)) != NULL && node)
60 node--;
61
62 return ct ? priv : NULL;
63 }
64
allocinfo_next(struct seq_file * m,void * arg,loff_t * pos)65 static void *allocinfo_next(struct seq_file *m, void *arg, loff_t *pos)
66 {
67 struct allocinfo_private *priv = (struct allocinfo_private *)arg;
68 struct codetag *ct = codetag_next_ct(&priv->iter);
69
70 (*pos)++;
71 if (!ct)
72 return NULL;
73
74 return priv;
75 }
76
allocinfo_stop(struct seq_file * m,void * arg)77 static void allocinfo_stop(struct seq_file *m, void *arg)
78 {
79 struct allocinfo_private *priv = (struct allocinfo_private *)m->private;
80
81 if (priv) {
82 codetag_lock_module_list(alloc_tag_cttype, false);
83 kfree(priv);
84 }
85 }
86
print_allocinfo_header(struct seq_buf * buf)87 static void print_allocinfo_header(struct seq_buf *buf)
88 {
89 /* Output format version, so we can change it. */
90 seq_buf_printf(buf, "allocinfo - version: 1.0\n");
91 seq_buf_printf(buf, "# <size> <calls> <tag info>\n");
92 }
93
alloc_tag_to_text(struct seq_buf * out,struct codetag * ct)94 static void alloc_tag_to_text(struct seq_buf *out, struct codetag *ct)
95 {
96 struct alloc_tag *tag = ct_to_alloc_tag(ct);
97 struct alloc_tag_counters counter = alloc_tag_read(tag);
98 s64 bytes = counter.bytes;
99
100 seq_buf_printf(out, "%12lli %8llu ", bytes, counter.calls);
101 codetag_to_text(out, ct);
102 seq_buf_putc(out, ' ');
103 seq_buf_putc(out, '\n');
104 }
105
allocinfo_show(struct seq_file * m,void * arg)106 static int allocinfo_show(struct seq_file *m, void *arg)
107 {
108 struct allocinfo_private *priv = (struct allocinfo_private *)arg;
109 char *bufp;
110 size_t n = seq_get_buf(m, &bufp);
111 struct seq_buf buf;
112
113 seq_buf_init(&buf, bufp, n);
114 if (priv->print_header) {
115 print_allocinfo_header(&buf);
116 priv->print_header = false;
117 }
118 alloc_tag_to_text(&buf, priv->iter.ct);
119 seq_commit(m, seq_buf_used(&buf));
120 return 0;
121 }
122
123 static const struct seq_operations allocinfo_seq_op = {
124 .start = allocinfo_start,
125 .next = allocinfo_next,
126 .stop = allocinfo_stop,
127 .show = allocinfo_show,
128 };
129
alloc_tag_top_users(struct codetag_bytes * tags,size_t count,bool can_sleep)130 size_t alloc_tag_top_users(struct codetag_bytes *tags, size_t count, bool can_sleep)
131 {
132 struct codetag_iterator iter;
133 struct codetag *ct;
134 struct codetag_bytes n;
135 unsigned int i, nr = 0;
136
137 if (can_sleep)
138 codetag_lock_module_list(alloc_tag_cttype, true);
139 else if (!codetag_trylock_module_list(alloc_tag_cttype))
140 return 0;
141
142 iter = codetag_get_ct_iter(alloc_tag_cttype);
143 while ((ct = codetag_next_ct(&iter))) {
144 struct alloc_tag_counters counter = alloc_tag_read(ct_to_alloc_tag(ct));
145
146 n.ct = ct;
147 n.bytes = counter.bytes;
148
149 for (i = 0; i < nr; i++)
150 if (n.bytes > tags[i].bytes)
151 break;
152
153 if (i < count) {
154 nr -= nr == count;
155 memmove(&tags[i + 1],
156 &tags[i],
157 sizeof(tags[0]) * (nr - i));
158 nr++;
159 tags[i] = n;
160 }
161 }
162
163 codetag_lock_module_list(alloc_tag_cttype, false);
164
165 return nr;
166 }
167
pgalloc_tag_split(struct folio * folio,int old_order,int new_order)168 void pgalloc_tag_split(struct folio *folio, int old_order, int new_order)
169 {
170 int i;
171 struct alloc_tag *tag;
172 unsigned int nr_pages = 1 << new_order;
173
174 if (!mem_alloc_profiling_enabled())
175 return;
176
177 tag = pgalloc_tag_get(&folio->page);
178 if (!tag)
179 return;
180
181 for (i = nr_pages; i < (1 << old_order); i += nr_pages) {
182 union pgtag_ref_handle handle;
183 union codetag_ref ref;
184
185 if (get_page_tag_ref(folio_page(folio, i), &ref, &handle)) {
186 /* Set new reference to point to the original tag */
187 alloc_tag_ref_set(&ref, tag);
188 update_page_tag_ref(handle, &ref);
189 put_page_tag_ref(handle);
190 }
191 }
192 }
193
pgalloc_tag_swap(struct folio * new,struct folio * old)194 void pgalloc_tag_swap(struct folio *new, struct folio *old)
195 {
196 union pgtag_ref_handle handle_old, handle_new;
197 union codetag_ref ref_old, ref_new;
198 struct alloc_tag *tag_old, *tag_new;
199
200 if (!mem_alloc_profiling_enabled())
201 return;
202
203 tag_old = pgalloc_tag_get(&old->page);
204 if (!tag_old)
205 return;
206 tag_new = pgalloc_tag_get(&new->page);
207 if (!tag_new)
208 return;
209
210 if (!get_page_tag_ref(&old->page, &ref_old, &handle_old))
211 return;
212 if (!get_page_tag_ref(&new->page, &ref_new, &handle_new)) {
213 put_page_tag_ref(handle_old);
214 return;
215 }
216
217 /*
218 * Clear tag references to avoid debug warning when using
219 * __alloc_tag_ref_set() with non-empty reference.
220 */
221 set_codetag_empty(&ref_old);
222 set_codetag_empty(&ref_new);
223
224 /* swap tags */
225 __alloc_tag_ref_set(&ref_old, tag_new);
226 update_page_tag_ref(handle_old, &ref_old);
227 __alloc_tag_ref_set(&ref_new, tag_old);
228 update_page_tag_ref(handle_new, &ref_new);
229
230 put_page_tag_ref(handle_old);
231 put_page_tag_ref(handle_new);
232 }
233
shutdown_mem_profiling(bool remove_file)234 static void shutdown_mem_profiling(bool remove_file)
235 {
236 if (mem_alloc_profiling_enabled())
237 static_branch_disable(&mem_alloc_profiling_key);
238
239 if (!mem_profiling_support)
240 return;
241
242 if (remove_file)
243 remove_proc_entry(ALLOCINFO_FILE_NAME, NULL);
244 mem_profiling_support = false;
245 }
246
procfs_init(void)247 static void __init procfs_init(void)
248 {
249 if (!mem_profiling_support)
250 return;
251
252 if (!proc_create_seq(ALLOCINFO_FILE_NAME, 0400, NULL, &allocinfo_seq_op)) {
253 pr_err("Failed to create %s file\n", ALLOCINFO_FILE_NAME);
254 shutdown_mem_profiling(false);
255 }
256 }
257
alloc_tag_sec_init(void)258 void __init alloc_tag_sec_init(void)
259 {
260 struct alloc_tag *last_codetag;
261
262 if (!mem_profiling_support)
263 return;
264
265 if (!static_key_enabled(&mem_profiling_compressed))
266 return;
267
268 kernel_tags.first_tag = (struct alloc_tag *)kallsyms_lookup_name(
269 SECTION_START(ALLOC_TAG_SECTION_NAME));
270 last_codetag = (struct alloc_tag *)kallsyms_lookup_name(
271 SECTION_STOP(ALLOC_TAG_SECTION_NAME));
272 kernel_tags.count = last_codetag - kernel_tags.first_tag;
273
274 /* Check if kernel tags fit into page flags */
275 if (kernel_tags.count > (1UL << NR_UNUSED_PAGEFLAG_BITS)) {
276 shutdown_mem_profiling(false); /* allocinfo file does not exist yet */
277 pr_err("%lu allocation tags cannot be references using %d available page flag bits. Memory allocation profiling is disabled!\n",
278 kernel_tags.count, NR_UNUSED_PAGEFLAG_BITS);
279 return;
280 }
281
282 alloc_tag_ref_offs = (LRU_REFS_PGOFF - NR_UNUSED_PAGEFLAG_BITS);
283 alloc_tag_ref_mask = ((1UL << NR_UNUSED_PAGEFLAG_BITS) - 1);
284 pr_debug("Memory allocation profiling compression is using %d page flag bits!\n",
285 NR_UNUSED_PAGEFLAG_BITS);
286 }
287
288 #ifdef CONFIG_MODULES
289
290 static struct maple_tree mod_area_mt = MTREE_INIT(mod_area_mt, MT_FLAGS_ALLOC_RANGE);
291 static struct vm_struct *vm_module_tags;
292 /* A dummy object used to indicate an unloaded module */
293 static struct module unloaded_mod;
294 /* A dummy object used to indicate a module prepended area */
295 static struct module prepend_mod;
296
297 struct alloc_tag_module_section module_tags;
298
alloc_tag_align(unsigned long val)299 static inline unsigned long alloc_tag_align(unsigned long val)
300 {
301 if (!static_key_enabled(&mem_profiling_compressed)) {
302 /* No alignment requirements when we are not indexing the tags */
303 return val;
304 }
305
306 if (val % sizeof(struct alloc_tag) == 0)
307 return val;
308 return ((val / sizeof(struct alloc_tag)) + 1) * sizeof(struct alloc_tag);
309 }
310
ensure_alignment(unsigned long align,unsigned int * prepend)311 static bool ensure_alignment(unsigned long align, unsigned int *prepend)
312 {
313 if (!static_key_enabled(&mem_profiling_compressed)) {
314 /* No alignment requirements when we are not indexing the tags */
315 return true;
316 }
317
318 /*
319 * If alloc_tag size is not a multiple of required alignment, tag
320 * indexing does not work.
321 */
322 if (!IS_ALIGNED(sizeof(struct alloc_tag), align))
323 return false;
324
325 /* Ensure prepend consumes multiple of alloc_tag-sized blocks */
326 if (*prepend)
327 *prepend = alloc_tag_align(*prepend);
328
329 return true;
330 }
331
tags_addressable(void)332 static inline bool tags_addressable(void)
333 {
334 unsigned long tag_idx_count;
335
336 if (!static_key_enabled(&mem_profiling_compressed))
337 return true; /* with page_ext tags are always addressable */
338
339 tag_idx_count = CODETAG_ID_FIRST + kernel_tags.count +
340 module_tags.size / sizeof(struct alloc_tag);
341
342 return tag_idx_count < (1UL << NR_UNUSED_PAGEFLAG_BITS);
343 }
344
needs_section_mem(struct module * mod,unsigned long size)345 static bool needs_section_mem(struct module *mod, unsigned long size)
346 {
347 if (!mem_profiling_support)
348 return false;
349
350 return size >= sizeof(struct alloc_tag);
351 }
352
find_used_tag(struct alloc_tag * from,struct alloc_tag * to)353 static struct alloc_tag *find_used_tag(struct alloc_tag *from, struct alloc_tag *to)
354 {
355 while (from <= to) {
356 struct alloc_tag_counters counter;
357
358 counter = alloc_tag_read(from);
359 if (counter.bytes)
360 return from;
361 from++;
362 }
363
364 return NULL;
365 }
366
367 /* Called with mod_area_mt locked */
clean_unused_module_areas_locked(void)368 static void clean_unused_module_areas_locked(void)
369 {
370 MA_STATE(mas, &mod_area_mt, 0, module_tags.size);
371 struct module *val;
372
373 mas_for_each(&mas, val, module_tags.size) {
374 if (val != &unloaded_mod)
375 continue;
376
377 /* Release area if all tags are unused */
378 if (!find_used_tag((struct alloc_tag *)(module_tags.start_addr + mas.index),
379 (struct alloc_tag *)(module_tags.start_addr + mas.last)))
380 mas_erase(&mas);
381 }
382 }
383
384 /* Called with mod_area_mt locked */
find_aligned_area(struct ma_state * mas,unsigned long section_size,unsigned long size,unsigned int prepend,unsigned long align)385 static bool find_aligned_area(struct ma_state *mas, unsigned long section_size,
386 unsigned long size, unsigned int prepend, unsigned long align)
387 {
388 bool cleanup_done = false;
389
390 repeat:
391 /* Try finding exact size and hope the start is aligned */
392 if (!mas_empty_area(mas, 0, section_size - 1, prepend + size)) {
393 if (IS_ALIGNED(mas->index + prepend, align))
394 return true;
395
396 /* Try finding larger area to align later */
397 mas_reset(mas);
398 if (!mas_empty_area(mas, 0, section_size - 1,
399 size + prepend + align - 1))
400 return true;
401 }
402
403 /* No free area, try cleanup stale data and repeat the search once */
404 if (!cleanup_done) {
405 clean_unused_module_areas_locked();
406 cleanup_done = true;
407 mas_reset(mas);
408 goto repeat;
409 }
410
411 return false;
412 }
413
vm_module_tags_populate(void)414 static int vm_module_tags_populate(void)
415 {
416 unsigned long phys_end = ALIGN_DOWN(module_tags.start_addr, PAGE_SIZE) +
417 (vm_module_tags->nr_pages << PAGE_SHIFT);
418 unsigned long new_end = module_tags.start_addr + module_tags.size;
419
420 if (phys_end < new_end) {
421 struct page **next_page = vm_module_tags->pages + vm_module_tags->nr_pages;
422 unsigned long old_shadow_end = ALIGN(phys_end, MODULE_ALIGN);
423 unsigned long new_shadow_end = ALIGN(new_end, MODULE_ALIGN);
424 unsigned long more_pages;
425 unsigned long nr;
426
427 more_pages = ALIGN(new_end - phys_end, PAGE_SIZE) >> PAGE_SHIFT;
428 nr = alloc_pages_bulk_node(GFP_KERNEL | __GFP_NOWARN,
429 NUMA_NO_NODE, more_pages, next_page);
430 if (nr < more_pages ||
431 vmap_pages_range(phys_end, phys_end + (nr << PAGE_SHIFT), PAGE_KERNEL,
432 next_page, PAGE_SHIFT) < 0) {
433 /* Clean up and error out */
434 for (int i = 0; i < nr; i++)
435 __free_page(next_page[i]);
436 return -ENOMEM;
437 }
438
439 vm_module_tags->nr_pages += nr;
440
441 /*
442 * Kasan allocates 1 byte of shadow for every 8 bytes of data.
443 * When kasan_alloc_module_shadow allocates shadow memory,
444 * its unit of allocation is a page.
445 * Therefore, here we need to align to MODULE_ALIGN.
446 */
447 if (old_shadow_end < new_shadow_end)
448 kasan_alloc_module_shadow((void *)old_shadow_end,
449 new_shadow_end - old_shadow_end,
450 GFP_KERNEL);
451 }
452
453 /*
454 * Mark the pages as accessible, now that they are mapped.
455 * With hardware tag-based KASAN, marking is skipped for
456 * non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc().
457 */
458 kasan_unpoison_vmalloc((void *)module_tags.start_addr,
459 new_end - module_tags.start_addr,
460 KASAN_VMALLOC_PROT_NORMAL);
461
462 return 0;
463 }
464
reserve_module_tags(struct module * mod,unsigned long size,unsigned int prepend,unsigned long align)465 static void *reserve_module_tags(struct module *mod, unsigned long size,
466 unsigned int prepend, unsigned long align)
467 {
468 unsigned long section_size = module_tags.end_addr - module_tags.start_addr;
469 MA_STATE(mas, &mod_area_mt, 0, section_size - 1);
470 unsigned long offset;
471 void *ret = NULL;
472
473 /* If no tags return error */
474 if (size < sizeof(struct alloc_tag))
475 return ERR_PTR(-EINVAL);
476
477 /*
478 * align is always power of 2, so we can use IS_ALIGNED and ALIGN.
479 * align 0 or 1 means no alignment, to simplify set to 1.
480 */
481 if (!align)
482 align = 1;
483
484 if (!ensure_alignment(align, &prepend)) {
485 shutdown_mem_profiling(true);
486 pr_err("%s: alignment %lu is incompatible with allocation tag indexing. Memory allocation profiling is disabled!\n",
487 mod->name, align);
488 return ERR_PTR(-EINVAL);
489 }
490
491 mas_lock(&mas);
492 if (!find_aligned_area(&mas, section_size, size, prepend, align)) {
493 ret = ERR_PTR(-ENOMEM);
494 goto unlock;
495 }
496
497 /* Mark found area as reserved */
498 offset = mas.index;
499 offset += prepend;
500 offset = ALIGN(offset, align);
501 if (offset != mas.index) {
502 unsigned long pad_start = mas.index;
503
504 mas.last = offset - 1;
505 mas_store(&mas, &prepend_mod);
506 if (mas_is_err(&mas)) {
507 ret = ERR_PTR(xa_err(mas.node));
508 goto unlock;
509 }
510 mas.index = offset;
511 mas.last = offset + size - 1;
512 mas_store(&mas, mod);
513 if (mas_is_err(&mas)) {
514 mas.index = pad_start;
515 mas_erase(&mas);
516 ret = ERR_PTR(xa_err(mas.node));
517 }
518 } else {
519 mas.last = offset + size - 1;
520 mas_store(&mas, mod);
521 if (mas_is_err(&mas))
522 ret = ERR_PTR(xa_err(mas.node));
523 }
524 unlock:
525 mas_unlock(&mas);
526
527 if (IS_ERR(ret))
528 return ret;
529
530 if (module_tags.size < offset + size) {
531 int grow_res;
532
533 module_tags.size = offset + size;
534 if (mem_alloc_profiling_enabled() && !tags_addressable()) {
535 shutdown_mem_profiling(true);
536 pr_warn("With module %s there are too many tags to fit in %d page flag bits. Memory allocation profiling is disabled!\n",
537 mod->name, NR_UNUSED_PAGEFLAG_BITS);
538 }
539
540 grow_res = vm_module_tags_populate();
541 if (grow_res) {
542 shutdown_mem_profiling(true);
543 pr_err("Failed to allocate memory for allocation tags in the module %s. Memory allocation profiling is disabled!\n",
544 mod->name);
545 return ERR_PTR(grow_res);
546 }
547 }
548
549 return (struct alloc_tag *)(module_tags.start_addr + offset);
550 }
551
release_module_tags(struct module * mod,bool used)552 static void release_module_tags(struct module *mod, bool used)
553 {
554 MA_STATE(mas, &mod_area_mt, module_tags.size, module_tags.size);
555 struct alloc_tag *tag;
556 struct module *val;
557
558 mas_lock(&mas);
559 mas_for_each_rev(&mas, val, 0)
560 if (val == mod)
561 break;
562
563 if (!val) /* module not found */
564 goto out;
565
566 if (!used)
567 goto release_area;
568
569 /* Find out if the area is used */
570 tag = find_used_tag((struct alloc_tag *)(module_tags.start_addr + mas.index),
571 (struct alloc_tag *)(module_tags.start_addr + mas.last));
572 if (tag) {
573 struct alloc_tag_counters counter = alloc_tag_read(tag);
574
575 pr_info("%s:%u module %s func:%s has %llu allocated at module unload\n",
576 tag->ct.filename, tag->ct.lineno, tag->ct.modname,
577 tag->ct.function, counter.bytes);
578 } else {
579 used = false;
580 }
581 release_area:
582 mas_store(&mas, used ? &unloaded_mod : NULL);
583 val = mas_prev_range(&mas, 0);
584 if (val == &prepend_mod)
585 mas_store(&mas, NULL);
586 out:
587 mas_unlock(&mas);
588 }
589
replace_module(struct module * mod,struct module * new_mod)590 static void replace_module(struct module *mod, struct module *new_mod)
591 {
592 MA_STATE(mas, &mod_area_mt, 0, module_tags.size);
593 struct module *val;
594
595 mas_lock(&mas);
596 mas_for_each(&mas, val, module_tags.size) {
597 if (val != mod)
598 continue;
599
600 mas_store_gfp(&mas, new_mod, GFP_KERNEL);
601 break;
602 }
603 mas_unlock(&mas);
604 }
605
alloc_mod_tags_mem(void)606 static int __init alloc_mod_tags_mem(void)
607 {
608 /* Map space to copy allocation tags */
609 vm_module_tags = execmem_vmap(MODULE_ALLOC_TAG_VMAP_SIZE);
610 if (!vm_module_tags) {
611 pr_err("Failed to map %lu bytes for module allocation tags\n",
612 MODULE_ALLOC_TAG_VMAP_SIZE);
613 module_tags.start_addr = 0;
614 return -ENOMEM;
615 }
616
617 vm_module_tags->pages = kmalloc_array(get_vm_area_size(vm_module_tags) >> PAGE_SHIFT,
618 sizeof(struct page *), GFP_KERNEL | __GFP_ZERO);
619 if (!vm_module_tags->pages) {
620 free_vm_area(vm_module_tags);
621 return -ENOMEM;
622 }
623
624 module_tags.start_addr = (unsigned long)vm_module_tags->addr;
625 module_tags.end_addr = module_tags.start_addr + MODULE_ALLOC_TAG_VMAP_SIZE;
626 /* Ensure the base is alloc_tag aligned when required for indexing */
627 module_tags.start_addr = alloc_tag_align(module_tags.start_addr);
628
629 return 0;
630 }
631
free_mod_tags_mem(void)632 static void __init free_mod_tags_mem(void)
633 {
634 int i;
635
636 module_tags.start_addr = 0;
637 for (i = 0; i < vm_module_tags->nr_pages; i++)
638 __free_page(vm_module_tags->pages[i]);
639 kfree(vm_module_tags->pages);
640 free_vm_area(vm_module_tags);
641 }
642
643 #else /* CONFIG_MODULES */
644
alloc_mod_tags_mem(void)645 static inline int alloc_mod_tags_mem(void) { return 0; }
free_mod_tags_mem(void)646 static inline void free_mod_tags_mem(void) {}
647
648 #endif /* CONFIG_MODULES */
649
650 /* See: Documentation/mm/allocation-profiling.rst */
setup_early_mem_profiling(char * str)651 static int __init setup_early_mem_profiling(char *str)
652 {
653 bool compressed = false;
654 bool enable;
655
656 if (!str || !str[0])
657 return -EINVAL;
658
659 if (!strncmp(str, "never", 5)) {
660 enable = false;
661 mem_profiling_support = false;
662 pr_info("Memory allocation profiling is disabled!\n");
663 } else {
664 char *token = strsep(&str, ",");
665
666 if (kstrtobool(token, &enable))
667 return -EINVAL;
668
669 if (str) {
670
671 if (strcmp(str, "compressed"))
672 return -EINVAL;
673
674 compressed = true;
675 }
676 mem_profiling_support = true;
677 pr_info("Memory allocation profiling is enabled %s compression and is turned %s!\n",
678 compressed ? "with" : "without", enable ? "on" : "off");
679 }
680
681 if (enable != mem_alloc_profiling_enabled()) {
682 if (enable)
683 static_branch_enable(&mem_alloc_profiling_key);
684 else
685 static_branch_disable(&mem_alloc_profiling_key);
686 }
687 if (compressed != static_key_enabled(&mem_profiling_compressed)) {
688 if (compressed)
689 static_branch_enable(&mem_profiling_compressed);
690 else
691 static_branch_disable(&mem_profiling_compressed);
692 }
693
694 return 0;
695 }
696 early_param("sysctl.vm.mem_profiling", setup_early_mem_profiling);
697
need_page_alloc_tagging(void)698 static __init bool need_page_alloc_tagging(void)
699 {
700 if (static_key_enabled(&mem_profiling_compressed))
701 return false;
702
703 return mem_profiling_support;
704 }
705
init_page_alloc_tagging(void)706 static __init void init_page_alloc_tagging(void)
707 {
708 }
709
710 struct page_ext_operations page_alloc_tagging_ops = {
711 .size = sizeof(union codetag_ref),
712 .need = need_page_alloc_tagging,
713 .init = init_page_alloc_tagging,
714 };
715 EXPORT_SYMBOL(page_alloc_tagging_ops);
716
717 #ifdef CONFIG_SYSCTL
718 static struct ctl_table memory_allocation_profiling_sysctls[] = {
719 {
720 .procname = "mem_profiling",
721 .data = &mem_alloc_profiling_key,
722 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
723 .mode = 0444,
724 #else
725 .mode = 0644,
726 #endif
727 .proc_handler = proc_do_static_key,
728 },
729 };
730
sysctl_init(void)731 static void __init sysctl_init(void)
732 {
733 if (!mem_profiling_support)
734 memory_allocation_profiling_sysctls[0].mode = 0444;
735
736 register_sysctl_init("vm", memory_allocation_profiling_sysctls);
737 }
738 #else /* CONFIG_SYSCTL */
sysctl_init(void)739 static inline void sysctl_init(void) {}
740 #endif /* CONFIG_SYSCTL */
741
alloc_tag_init(void)742 static int __init alloc_tag_init(void)
743 {
744 const struct codetag_type_desc desc = {
745 .section = ALLOC_TAG_SECTION_NAME,
746 .tag_size = sizeof(struct alloc_tag),
747 #ifdef CONFIG_MODULES
748 .needs_section_mem = needs_section_mem,
749 .alloc_section_mem = reserve_module_tags,
750 .free_section_mem = release_module_tags,
751 .module_replaced = replace_module,
752 #endif
753 };
754 int res;
755
756 res = alloc_mod_tags_mem();
757 if (res)
758 return res;
759
760 alloc_tag_cttype = codetag_register_type(&desc);
761 if (IS_ERR(alloc_tag_cttype)) {
762 free_mod_tags_mem();
763 return PTR_ERR(alloc_tag_cttype);
764 }
765
766 sysctl_init();
767 procfs_init();
768
769 return 0;
770 }
771 module_init(alloc_tag_init);
772