Loading...
1/*
2 * Processor cache information made available to userspace via sysfs;
3 * intended to be compatible with x86 intel_cacheinfo implementation.
4 *
5 * Copyright 2008 IBM Corporation
6 * Author: Nathan Lynch
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version
10 * 2 as published by the Free Software Foundation.
11 */
12
13#include <linux/cpu.h>
14#include <linux/cpumask.h>
15#include <linux/kernel.h>
16#include <linux/kobject.h>
17#include <linux/list.h>
18#include <linux/notifier.h>
19#include <linux/of.h>
20#include <linux/percpu.h>
21#include <linux/slab.h>
22#include <asm/prom.h>
23
24#include "cacheinfo.h"
25
26/* per-cpu object for tracking:
27 * - a "cache" kobject for the top-level directory
28 * - a list of "index" objects representing the cpu's local cache hierarchy
29 */
30struct cache_dir {
31 struct kobject *kobj; /* bare (not embedded) kobject for cache
32 * directory */
33 struct cache_index_dir *index; /* list of index objects */
34};
35
36/* "index" object: each cpu's cache directory has an index
37 * subdirectory corresponding to a cache object associated with the
38 * cpu. This object's lifetime is managed via the embedded kobject.
39 */
40struct cache_index_dir {
41 struct kobject kobj;
42 struct cache_index_dir *next; /* next index in parent directory */
43 struct cache *cache;
44};
45
46/* Template for determining which OF properties to query for a given
47 * cache type */
48struct cache_type_info {
49 const char *name;
50 const char *size_prop;
51
52 /* Allow for both [di]-cache-line-size and
53 * [di]-cache-block-size properties. According to the PowerPC
54 * Processor binding, -line-size should be provided if it
55 * differs from the cache block size (that which is operated
56 * on by cache instructions), so we look for -line-size first.
57 * See cache_get_line_size(). */
58
59 const char *line_size_props[2];
60 const char *nr_sets_prop;
61};
62
63/* These are used to index the cache_type_info array. */
64#define CACHE_TYPE_UNIFIED 0 /* cache-size, cache-block-size, etc. */
65#define CACHE_TYPE_UNIFIED_D 1 /* d-cache-size, d-cache-block-size, etc */
66#define CACHE_TYPE_INSTRUCTION 2
67#define CACHE_TYPE_DATA 3
68
69static const struct cache_type_info cache_type_info[] = {
70 {
71 /* Embedded systems that use cache-size, cache-block-size,
72 * etc. for the Unified (typically L2) cache. */
73 .name = "Unified",
74 .size_prop = "cache-size",
75 .line_size_props = { "cache-line-size",
76 "cache-block-size", },
77 .nr_sets_prop = "cache-sets",
78 },
79 {
80 /* PowerPC Processor binding says the [di]-cache-*
81 * must be equal on unified caches, so just use
82 * d-cache properties. */
83 .name = "Unified",
84 .size_prop = "d-cache-size",
85 .line_size_props = { "d-cache-line-size",
86 "d-cache-block-size", },
87 .nr_sets_prop = "d-cache-sets",
88 },
89 {
90 .name = "Instruction",
91 .size_prop = "i-cache-size",
92 .line_size_props = { "i-cache-line-size",
93 "i-cache-block-size", },
94 .nr_sets_prop = "i-cache-sets",
95 },
96 {
97 .name = "Data",
98 .size_prop = "d-cache-size",
99 .line_size_props = { "d-cache-line-size",
100 "d-cache-block-size", },
101 .nr_sets_prop = "d-cache-sets",
102 },
103};
104
105/* Cache object: each instance of this corresponds to a distinct cache
106 * in the system. There are separate objects for Harvard caches: one
107 * each for instruction and data, and each refers to the same OF node.
108 * The refcount of the OF node is elevated for the lifetime of the
109 * cache object. A cache object is released when its shared_cpu_map
110 * is cleared (see cache_cpu_clear).
111 *
112 * A cache object is on two lists: an unsorted global list
113 * (cache_list) of cache objects; and a singly-linked list
114 * representing the local cache hierarchy, which is ordered by level
115 * (e.g. L1d -> L1i -> L2 -> L3).
116 */
117struct cache {
118 struct device_node *ofnode; /* OF node for this cache, may be cpu */
119 struct cpumask shared_cpu_map; /* online CPUs using this cache */
120 int type; /* split cache disambiguation */
121 int level; /* level not explicit in device tree */
122 struct list_head list; /* global list of cache objects */
123 struct cache *next_local; /* next cache of >= level */
124};
125
126static DEFINE_PER_CPU(struct cache_dir *, cache_dir_pcpu);
127
128/* traversal/modification of this list occurs only at cpu hotplug time;
129 * access is serialized by cpu hotplug locking
130 */
131static LIST_HEAD(cache_list);
132
133static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *k)
134{
135 return container_of(k, struct cache_index_dir, kobj);
136}
137
138static const char *cache_type_string(const struct cache *cache)
139{
140 return cache_type_info[cache->type].name;
141}
142
143static void cache_init(struct cache *cache, int type, int level,
144 struct device_node *ofnode)
145{
146 cache->type = type;
147 cache->level = level;
148 cache->ofnode = of_node_get(ofnode);
149 INIT_LIST_HEAD(&cache->list);
150 list_add(&cache->list, &cache_list);
151}
152
153static struct cache *new_cache(int type, int level, struct device_node *ofnode)
154{
155 struct cache *cache;
156
157 cache = kzalloc(sizeof(*cache), GFP_KERNEL);
158 if (cache)
159 cache_init(cache, type, level, ofnode);
160
161 return cache;
162}
163
164static void release_cache_debugcheck(struct cache *cache)
165{
166 struct cache *iter;
167
168 list_for_each_entry(iter, &cache_list, list)
169 WARN_ONCE(iter->next_local == cache,
170 "cache for %pOF(%s) refers to cache for %pOF(%s)\n",
171 iter->ofnode,
172 cache_type_string(iter),
173 cache->ofnode,
174 cache_type_string(cache));
175}
176
177static void release_cache(struct cache *cache)
178{
179 if (!cache)
180 return;
181
182 pr_debug("freeing L%d %s cache for %pOF\n", cache->level,
183 cache_type_string(cache), cache->ofnode);
184
185 release_cache_debugcheck(cache);
186 list_del(&cache->list);
187 of_node_put(cache->ofnode);
188 kfree(cache);
189}
190
191static void cache_cpu_set(struct cache *cache, int cpu)
192{
193 struct cache *next = cache;
194
195 while (next) {
196 WARN_ONCE(cpumask_test_cpu(cpu, &next->shared_cpu_map),
197 "CPU %i already accounted in %pOF(%s)\n",
198 cpu, next->ofnode,
199 cache_type_string(next));
200 cpumask_set_cpu(cpu, &next->shared_cpu_map);
201 next = next->next_local;
202 }
203}
204
205static int cache_size(const struct cache *cache, unsigned int *ret)
206{
207 const char *propname;
208 const __be32 *cache_size;
209
210 propname = cache_type_info[cache->type].size_prop;
211
212 cache_size = of_get_property(cache->ofnode, propname, NULL);
213 if (!cache_size)
214 return -ENODEV;
215
216 *ret = of_read_number(cache_size, 1);
217 return 0;
218}
219
220static int cache_size_kb(const struct cache *cache, unsigned int *ret)
221{
222 unsigned int size;
223
224 if (cache_size(cache, &size))
225 return -ENODEV;
226
227 *ret = size / 1024;
228 return 0;
229}
230
231/* not cache_line_size() because that's a macro in include/linux/cache.h */
232static int cache_get_line_size(const struct cache *cache, unsigned int *ret)
233{
234 const __be32 *line_size;
235 int i, lim;
236
237 lim = ARRAY_SIZE(cache_type_info[cache->type].line_size_props);
238
239 for (i = 0; i < lim; i++) {
240 const char *propname;
241
242 propname = cache_type_info[cache->type].line_size_props[i];
243 line_size = of_get_property(cache->ofnode, propname, NULL);
244 if (line_size)
245 break;
246 }
247
248 if (!line_size)
249 return -ENODEV;
250
251 *ret = of_read_number(line_size, 1);
252 return 0;
253}
254
255static int cache_nr_sets(const struct cache *cache, unsigned int *ret)
256{
257 const char *propname;
258 const __be32 *nr_sets;
259
260 propname = cache_type_info[cache->type].nr_sets_prop;
261
262 nr_sets = of_get_property(cache->ofnode, propname, NULL);
263 if (!nr_sets)
264 return -ENODEV;
265
266 *ret = of_read_number(nr_sets, 1);
267 return 0;
268}
269
270static int cache_associativity(const struct cache *cache, unsigned int *ret)
271{
272 unsigned int line_size;
273 unsigned int nr_sets;
274 unsigned int size;
275
276 if (cache_nr_sets(cache, &nr_sets))
277 goto err;
278
279 /* If the cache is fully associative, there is no need to
280 * check the other properties.
281 */
282 if (nr_sets == 1) {
283 *ret = 0;
284 return 0;
285 }
286
287 if (cache_get_line_size(cache, &line_size))
288 goto err;
289 if (cache_size(cache, &size))
290 goto err;
291
292 if (!(nr_sets > 0 && size > 0 && line_size > 0))
293 goto err;
294
295 *ret = (size / nr_sets) / line_size;
296 return 0;
297err:
298 return -ENODEV;
299}
300
301/* helper for dealing with split caches */
302static struct cache *cache_find_first_sibling(struct cache *cache)
303{
304 struct cache *iter;
305
306 if (cache->type == CACHE_TYPE_UNIFIED ||
307 cache->type == CACHE_TYPE_UNIFIED_D)
308 return cache;
309
310 list_for_each_entry(iter, &cache_list, list)
311 if (iter->ofnode == cache->ofnode && iter->next_local == cache)
312 return iter;
313
314 return cache;
315}
316
317/* return the first cache on a local list matching node */
318static struct cache *cache_lookup_by_node(const struct device_node *node)
319{
320 struct cache *cache = NULL;
321 struct cache *iter;
322
323 list_for_each_entry(iter, &cache_list, list) {
324 if (iter->ofnode != node)
325 continue;
326 cache = cache_find_first_sibling(iter);
327 break;
328 }
329
330 return cache;
331}
332
333static bool cache_node_is_unified(const struct device_node *np)
334{
335 return of_get_property(np, "cache-unified", NULL);
336}
337
338/*
339 * Unified caches can have two different sets of tags. Most embedded
340 * use cache-size, etc. for the unified cache size, but open firmware systems
341 * use d-cache-size, etc. Check on initialization for which type we have, and
342 * return the appropriate structure type. Assume it's embedded if it isn't
343 * open firmware. If it's yet a 3rd type, then there will be missing entries
344 * in /sys/devices/system/cpu/cpu0/cache/index2/, and this code will need
345 * to be extended further.
346 */
347static int cache_is_unified_d(const struct device_node *np)
348{
349 return of_get_property(np,
350 cache_type_info[CACHE_TYPE_UNIFIED_D].size_prop, NULL) ?
351 CACHE_TYPE_UNIFIED_D : CACHE_TYPE_UNIFIED;
352}
353
354/*
355 */
356static struct cache *cache_do_one_devnode_unified(struct device_node *node, int level)
357{
358 pr_debug("creating L%d ucache for %pOF\n", level, node);
359
360 return new_cache(cache_is_unified_d(node), level, node);
361}
362
363static struct cache *cache_do_one_devnode_split(struct device_node *node,
364 int level)
365{
366 struct cache *dcache, *icache;
367
368 pr_debug("creating L%d dcache and icache for %pOF\n", level,
369 node);
370
371 dcache = new_cache(CACHE_TYPE_DATA, level, node);
372 icache = new_cache(CACHE_TYPE_INSTRUCTION, level, node);
373
374 if (!dcache || !icache)
375 goto err;
376
377 dcache->next_local = icache;
378
379 return dcache;
380err:
381 release_cache(dcache);
382 release_cache(icache);
383 return NULL;
384}
385
386static struct cache *cache_do_one_devnode(struct device_node *node, int level)
387{
388 struct cache *cache;
389
390 if (cache_node_is_unified(node))
391 cache = cache_do_one_devnode_unified(node, level);
392 else
393 cache = cache_do_one_devnode_split(node, level);
394
395 return cache;
396}
397
398static struct cache *cache_lookup_or_instantiate(struct device_node *node,
399 int level)
400{
401 struct cache *cache;
402
403 cache = cache_lookup_by_node(node);
404
405 WARN_ONCE(cache && cache->level != level,
406 "cache level mismatch on lookup (got %d, expected %d)\n",
407 cache->level, level);
408
409 if (!cache)
410 cache = cache_do_one_devnode(node, level);
411
412 return cache;
413}
414
415static void link_cache_lists(struct cache *smaller, struct cache *bigger)
416{
417 while (smaller->next_local) {
418 if (smaller->next_local == bigger)
419 return; /* already linked */
420 smaller = smaller->next_local;
421 }
422
423 smaller->next_local = bigger;
424}
425
426static void do_subsidiary_caches_debugcheck(struct cache *cache)
427{
428 WARN_ON_ONCE(cache->level != 1);
429 WARN_ON_ONCE(strcmp(cache->ofnode->type, "cpu"));
430}
431
432static void do_subsidiary_caches(struct cache *cache)
433{
434 struct device_node *subcache_node;
435 int level = cache->level;
436
437 do_subsidiary_caches_debugcheck(cache);
438
439 while ((subcache_node = of_find_next_cache_node(cache->ofnode))) {
440 struct cache *subcache;
441
442 level++;
443 subcache = cache_lookup_or_instantiate(subcache_node, level);
444 of_node_put(subcache_node);
445 if (!subcache)
446 break;
447
448 link_cache_lists(cache, subcache);
449 cache = subcache;
450 }
451}
452
453static struct cache *cache_chain_instantiate(unsigned int cpu_id)
454{
455 struct device_node *cpu_node;
456 struct cache *cpu_cache = NULL;
457
458 pr_debug("creating cache object(s) for CPU %i\n", cpu_id);
459
460 cpu_node = of_get_cpu_node(cpu_id, NULL);
461 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
462 if (!cpu_node)
463 goto out;
464
465 cpu_cache = cache_lookup_or_instantiate(cpu_node, 1);
466 if (!cpu_cache)
467 goto out;
468
469 do_subsidiary_caches(cpu_cache);
470
471 cache_cpu_set(cpu_cache, cpu_id);
472out:
473 of_node_put(cpu_node);
474
475 return cpu_cache;
476}
477
478static struct cache_dir *cacheinfo_create_cache_dir(unsigned int cpu_id)
479{
480 struct cache_dir *cache_dir;
481 struct device *dev;
482 struct kobject *kobj = NULL;
483
484 dev = get_cpu_device(cpu_id);
485 WARN_ONCE(!dev, "no dev for CPU %i\n", cpu_id);
486 if (!dev)
487 goto err;
488
489 kobj = kobject_create_and_add("cache", &dev->kobj);
490 if (!kobj)
491 goto err;
492
493 cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
494 if (!cache_dir)
495 goto err;
496
497 cache_dir->kobj = kobj;
498
499 WARN_ON_ONCE(per_cpu(cache_dir_pcpu, cpu_id) != NULL);
500
501 per_cpu(cache_dir_pcpu, cpu_id) = cache_dir;
502
503 return cache_dir;
504err:
505 kobject_put(kobj);
506 return NULL;
507}
508
509static void cache_index_release(struct kobject *kobj)
510{
511 struct cache_index_dir *index;
512
513 index = kobj_to_cache_index_dir(kobj);
514
515 pr_debug("freeing index directory for L%d %s cache\n",
516 index->cache->level, cache_type_string(index->cache));
517
518 kfree(index);
519}
520
521static ssize_t cache_index_show(struct kobject *k, struct attribute *attr, char *buf)
522{
523 struct kobj_attribute *kobj_attr;
524
525 kobj_attr = container_of(attr, struct kobj_attribute, attr);
526
527 return kobj_attr->show(k, kobj_attr, buf);
528}
529
530static struct cache *index_kobj_to_cache(struct kobject *k)
531{
532 struct cache_index_dir *index;
533
534 index = kobj_to_cache_index_dir(k);
535
536 return index->cache;
537}
538
539static ssize_t size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
540{
541 unsigned int size_kb;
542 struct cache *cache;
543
544 cache = index_kobj_to_cache(k);
545
546 if (cache_size_kb(cache, &size_kb))
547 return -ENODEV;
548
549 return sprintf(buf, "%uK\n", size_kb);
550}
551
552static struct kobj_attribute cache_size_attr =
553 __ATTR(size, 0444, size_show, NULL);
554
555
556static ssize_t line_size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
557{
558 unsigned int line_size;
559 struct cache *cache;
560
561 cache = index_kobj_to_cache(k);
562
563 if (cache_get_line_size(cache, &line_size))
564 return -ENODEV;
565
566 return sprintf(buf, "%u\n", line_size);
567}
568
569static struct kobj_attribute cache_line_size_attr =
570 __ATTR(coherency_line_size, 0444, line_size_show, NULL);
571
572static ssize_t nr_sets_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
573{
574 unsigned int nr_sets;
575 struct cache *cache;
576
577 cache = index_kobj_to_cache(k);
578
579 if (cache_nr_sets(cache, &nr_sets))
580 return -ENODEV;
581
582 return sprintf(buf, "%u\n", nr_sets);
583}
584
585static struct kobj_attribute cache_nr_sets_attr =
586 __ATTR(number_of_sets, 0444, nr_sets_show, NULL);
587
588static ssize_t associativity_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
589{
590 unsigned int associativity;
591 struct cache *cache;
592
593 cache = index_kobj_to_cache(k);
594
595 if (cache_associativity(cache, &associativity))
596 return -ENODEV;
597
598 return sprintf(buf, "%u\n", associativity);
599}
600
601static struct kobj_attribute cache_assoc_attr =
602 __ATTR(ways_of_associativity, 0444, associativity_show, NULL);
603
604static ssize_t type_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
605{
606 struct cache *cache;
607
608 cache = index_kobj_to_cache(k);
609
610 return sprintf(buf, "%s\n", cache_type_string(cache));
611}
612
613static struct kobj_attribute cache_type_attr =
614 __ATTR(type, 0444, type_show, NULL);
615
616static ssize_t level_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
617{
618 struct cache_index_dir *index;
619 struct cache *cache;
620
621 index = kobj_to_cache_index_dir(k);
622 cache = index->cache;
623
624 return sprintf(buf, "%d\n", cache->level);
625}
626
627static struct kobj_attribute cache_level_attr =
628 __ATTR(level, 0444, level_show, NULL);
629
630static ssize_t shared_cpu_map_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
631{
632 struct cache_index_dir *index;
633 struct cache *cache;
634 int ret;
635
636 index = kobj_to_cache_index_dir(k);
637 cache = index->cache;
638
639 ret = scnprintf(buf, PAGE_SIZE - 1, "%*pb\n",
640 cpumask_pr_args(&cache->shared_cpu_map));
641 buf[ret++] = '\n';
642 buf[ret] = '\0';
643 return ret;
644}
645
646static struct kobj_attribute cache_shared_cpu_map_attr =
647 __ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);
648
649/* Attributes which should always be created -- the kobject/sysfs core
650 * does this automatically via kobj_type->default_attrs. This is the
651 * minimum data required to uniquely identify a cache.
652 */
653static struct attribute *cache_index_default_attrs[] = {
654 &cache_type_attr.attr,
655 &cache_level_attr.attr,
656 &cache_shared_cpu_map_attr.attr,
657 NULL,
658};
659
660/* Attributes which should be created if the cache device node has the
661 * right properties -- see cacheinfo_create_index_opt_attrs
662 */
663static struct kobj_attribute *cache_index_opt_attrs[] = {
664 &cache_size_attr,
665 &cache_line_size_attr,
666 &cache_nr_sets_attr,
667 &cache_assoc_attr,
668};
669
670static const struct sysfs_ops cache_index_ops = {
671 .show = cache_index_show,
672};
673
674static struct kobj_type cache_index_type = {
675 .release = cache_index_release,
676 .sysfs_ops = &cache_index_ops,
677 .default_attrs = cache_index_default_attrs,
678};
679
680static void cacheinfo_create_index_opt_attrs(struct cache_index_dir *dir)
681{
682 const char *cache_type;
683 struct cache *cache;
684 char *buf;
685 int i;
686
687 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
688 if (!buf)
689 return;
690
691 cache = dir->cache;
692 cache_type = cache_type_string(cache);
693
694 /* We don't want to create an attribute that can't provide a
695 * meaningful value. Check the return value of each optional
696 * attribute's ->show method before registering the
697 * attribute.
698 */
699 for (i = 0; i < ARRAY_SIZE(cache_index_opt_attrs); i++) {
700 struct kobj_attribute *attr;
701 ssize_t rc;
702
703 attr = cache_index_opt_attrs[i];
704
705 rc = attr->show(&dir->kobj, attr, buf);
706 if (rc <= 0) {
707 pr_debug("not creating %s attribute for "
708 "%pOF(%s) (rc = %zd)\n",
709 attr->attr.name, cache->ofnode,
710 cache_type, rc);
711 continue;
712 }
713 if (sysfs_create_file(&dir->kobj, &attr->attr))
714 pr_debug("could not create %s attribute for %pOF(%s)\n",
715 attr->attr.name, cache->ofnode, cache_type);
716 }
717
718 kfree(buf);
719}
720
721static void cacheinfo_create_index_dir(struct cache *cache, int index,
722 struct cache_dir *cache_dir)
723{
724 struct cache_index_dir *index_dir;
725 int rc;
726
727 index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
728 if (!index_dir)
729 goto err;
730
731 index_dir->cache = cache;
732
733 rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
734 cache_dir->kobj, "index%d", index);
735 if (rc)
736 goto err;
737
738 index_dir->next = cache_dir->index;
739 cache_dir->index = index_dir;
740
741 cacheinfo_create_index_opt_attrs(index_dir);
742
743 return;
744err:
745 kfree(index_dir);
746}
747
748static void cacheinfo_sysfs_populate(unsigned int cpu_id,
749 struct cache *cache_list)
750{
751 struct cache_dir *cache_dir;
752 struct cache *cache;
753 int index = 0;
754
755 cache_dir = cacheinfo_create_cache_dir(cpu_id);
756 if (!cache_dir)
757 return;
758
759 cache = cache_list;
760 while (cache) {
761 cacheinfo_create_index_dir(cache, index, cache_dir);
762 index++;
763 cache = cache->next_local;
764 }
765}
766
767void cacheinfo_cpu_online(unsigned int cpu_id)
768{
769 struct cache *cache;
770
771 cache = cache_chain_instantiate(cpu_id);
772 if (!cache)
773 return;
774
775 cacheinfo_sysfs_populate(cpu_id, cache);
776}
777
778/* functions needed to remove cache entry for cpu offline or suspend/resume */
779
780#if (defined(CONFIG_PPC_PSERIES) && defined(CONFIG_SUSPEND)) || \
781 defined(CONFIG_HOTPLUG_CPU)
782
783static struct cache *cache_lookup_by_cpu(unsigned int cpu_id)
784{
785 struct device_node *cpu_node;
786 struct cache *cache;
787
788 cpu_node = of_get_cpu_node(cpu_id, NULL);
789 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
790 if (!cpu_node)
791 return NULL;
792
793 cache = cache_lookup_by_node(cpu_node);
794 of_node_put(cpu_node);
795
796 return cache;
797}
798
799static void remove_index_dirs(struct cache_dir *cache_dir)
800{
801 struct cache_index_dir *index;
802
803 index = cache_dir->index;
804
805 while (index) {
806 struct cache_index_dir *next;
807
808 next = index->next;
809 kobject_put(&index->kobj);
810 index = next;
811 }
812}
813
814static void remove_cache_dir(struct cache_dir *cache_dir)
815{
816 remove_index_dirs(cache_dir);
817
818 /* Remove cache dir from sysfs */
819 kobject_del(cache_dir->kobj);
820
821 kobject_put(cache_dir->kobj);
822
823 kfree(cache_dir);
824}
825
826static void cache_cpu_clear(struct cache *cache, int cpu)
827{
828 while (cache) {
829 struct cache *next = cache->next_local;
830
831 WARN_ONCE(!cpumask_test_cpu(cpu, &cache->shared_cpu_map),
832 "CPU %i not accounted in %pOF(%s)\n",
833 cpu, cache->ofnode,
834 cache_type_string(cache));
835
836 cpumask_clear_cpu(cpu, &cache->shared_cpu_map);
837
838 /* Release the cache object if all the cpus using it
839 * are offline */
840 if (cpumask_empty(&cache->shared_cpu_map))
841 release_cache(cache);
842
843 cache = next;
844 }
845}
846
847void cacheinfo_cpu_offline(unsigned int cpu_id)
848{
849 struct cache_dir *cache_dir;
850 struct cache *cache;
851
852 /* Prevent userspace from seeing inconsistent state - remove
853 * the sysfs hierarchy first */
854 cache_dir = per_cpu(cache_dir_pcpu, cpu_id);
855
856 /* careful, sysfs population may have failed */
857 if (cache_dir)
858 remove_cache_dir(cache_dir);
859
860 per_cpu(cache_dir_pcpu, cpu_id) = NULL;
861
862 /* clear the CPU's bit in its cache chain, possibly freeing
863 * cache objects */
864 cache = cache_lookup_by_cpu(cpu_id);
865 if (cache)
866 cache_cpu_clear(cache, cpu_id);
867}
868#endif /* (CONFIG_PPC_PSERIES && CONFIG_SUSPEND) || CONFIG_HOTPLUG_CPU */
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Processor cache information made available to userspace via sysfs;
4 * intended to be compatible with x86 intel_cacheinfo implementation.
5 *
6 * Copyright 2008 IBM Corporation
7 * Author: Nathan Lynch
8 */
9
10#include <linux/cpu.h>
11#include <linux/cpumask.h>
12#include <linux/kernel.h>
13#include <linux/kobject.h>
14#include <linux/list.h>
15#include <linux/notifier.h>
16#include <linux/of.h>
17#include <linux/percpu.h>
18#include <linux/slab.h>
19#include <asm/prom.h>
20#include <asm/cputhreads.h>
21#include <asm/smp.h>
22
23#include "cacheinfo.h"
24
25/* per-cpu object for tracking:
26 * - a "cache" kobject for the top-level directory
27 * - a list of "index" objects representing the cpu's local cache hierarchy
28 */
29struct cache_dir {
30 struct kobject *kobj; /* bare (not embedded) kobject for cache
31 * directory */
32 struct cache_index_dir *index; /* list of index objects */
33};
34
35/* "index" object: each cpu's cache directory has an index
36 * subdirectory corresponding to a cache object associated with the
37 * cpu. This object's lifetime is managed via the embedded kobject.
38 */
39struct cache_index_dir {
40 struct kobject kobj;
41 struct cache_index_dir *next; /* next index in parent directory */
42 struct cache *cache;
43};
44
45/* Template for determining which OF properties to query for a given
46 * cache type */
47struct cache_type_info {
48 const char *name;
49 const char *size_prop;
50
51 /* Allow for both [di]-cache-line-size and
52 * [di]-cache-block-size properties. According to the PowerPC
53 * Processor binding, -line-size should be provided if it
54 * differs from the cache block size (that which is operated
55 * on by cache instructions), so we look for -line-size first.
56 * See cache_get_line_size(). */
57
58 const char *line_size_props[2];
59 const char *nr_sets_prop;
60};
61
62/* These are used to index the cache_type_info array. */
63#define CACHE_TYPE_UNIFIED 0 /* cache-size, cache-block-size, etc. */
64#define CACHE_TYPE_UNIFIED_D 1 /* d-cache-size, d-cache-block-size, etc */
65#define CACHE_TYPE_INSTRUCTION 2
66#define CACHE_TYPE_DATA 3
67
68static const struct cache_type_info cache_type_info[] = {
69 {
70 /* Embedded systems that use cache-size, cache-block-size,
71 * etc. for the Unified (typically L2) cache. */
72 .name = "Unified",
73 .size_prop = "cache-size",
74 .line_size_props = { "cache-line-size",
75 "cache-block-size", },
76 .nr_sets_prop = "cache-sets",
77 },
78 {
79 /* PowerPC Processor binding says the [di]-cache-*
80 * must be equal on unified caches, so just use
81 * d-cache properties. */
82 .name = "Unified",
83 .size_prop = "d-cache-size",
84 .line_size_props = { "d-cache-line-size",
85 "d-cache-block-size", },
86 .nr_sets_prop = "d-cache-sets",
87 },
88 {
89 .name = "Instruction",
90 .size_prop = "i-cache-size",
91 .line_size_props = { "i-cache-line-size",
92 "i-cache-block-size", },
93 .nr_sets_prop = "i-cache-sets",
94 },
95 {
96 .name = "Data",
97 .size_prop = "d-cache-size",
98 .line_size_props = { "d-cache-line-size",
99 "d-cache-block-size", },
100 .nr_sets_prop = "d-cache-sets",
101 },
102};
103
104/* Cache object: each instance of this corresponds to a distinct cache
105 * in the system. There are separate objects for Harvard caches: one
106 * each for instruction and data, and each refers to the same OF node.
107 * The refcount of the OF node is elevated for the lifetime of the
108 * cache object. A cache object is released when its shared_cpu_map
109 * is cleared (see cache_cpu_clear).
110 *
111 * A cache object is on two lists: an unsorted global list
112 * (cache_list) of cache objects; and a singly-linked list
113 * representing the local cache hierarchy, which is ordered by level
114 * (e.g. L1d -> L1i -> L2 -> L3).
115 */
116struct cache {
117 struct device_node *ofnode; /* OF node for this cache, may be cpu */
118 struct cpumask shared_cpu_map; /* online CPUs using this cache */
119 int type; /* split cache disambiguation */
120 int level; /* level not explicit in device tree */
121 struct list_head list; /* global list of cache objects */
122 struct cache *next_local; /* next cache of >= level */
123};
124
125static DEFINE_PER_CPU(struct cache_dir *, cache_dir_pcpu);
126
127/* traversal/modification of this list occurs only at cpu hotplug time;
128 * access is serialized by cpu hotplug locking
129 */
130static LIST_HEAD(cache_list);
131
132static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *k)
133{
134 return container_of(k, struct cache_index_dir, kobj);
135}
136
137static const char *cache_type_string(const struct cache *cache)
138{
139 return cache_type_info[cache->type].name;
140}
141
142static void cache_init(struct cache *cache, int type, int level,
143 struct device_node *ofnode)
144{
145 cache->type = type;
146 cache->level = level;
147 cache->ofnode = of_node_get(ofnode);
148 INIT_LIST_HEAD(&cache->list);
149 list_add(&cache->list, &cache_list);
150}
151
152static struct cache *new_cache(int type, int level, struct device_node *ofnode)
153{
154 struct cache *cache;
155
156 cache = kzalloc(sizeof(*cache), GFP_KERNEL);
157 if (cache)
158 cache_init(cache, type, level, ofnode);
159
160 return cache;
161}
162
163static void release_cache_debugcheck(struct cache *cache)
164{
165 struct cache *iter;
166
167 list_for_each_entry(iter, &cache_list, list)
168 WARN_ONCE(iter->next_local == cache,
169 "cache for %pOF(%s) refers to cache for %pOF(%s)\n",
170 iter->ofnode,
171 cache_type_string(iter),
172 cache->ofnode,
173 cache_type_string(cache));
174}
175
176static void release_cache(struct cache *cache)
177{
178 if (!cache)
179 return;
180
181 pr_debug("freeing L%d %s cache for %pOF\n", cache->level,
182 cache_type_string(cache), cache->ofnode);
183
184 release_cache_debugcheck(cache);
185 list_del(&cache->list);
186 of_node_put(cache->ofnode);
187 kfree(cache);
188}
189
190static void cache_cpu_set(struct cache *cache, int cpu)
191{
192 struct cache *next = cache;
193
194 while (next) {
195 WARN_ONCE(cpumask_test_cpu(cpu, &next->shared_cpu_map),
196 "CPU %i already accounted in %pOF(%s)\n",
197 cpu, next->ofnode,
198 cache_type_string(next));
199 cpumask_set_cpu(cpu, &next->shared_cpu_map);
200 next = next->next_local;
201 }
202}
203
204static int cache_size(const struct cache *cache, unsigned int *ret)
205{
206 const char *propname;
207 const __be32 *cache_size;
208
209 propname = cache_type_info[cache->type].size_prop;
210
211 cache_size = of_get_property(cache->ofnode, propname, NULL);
212 if (!cache_size)
213 return -ENODEV;
214
215 *ret = of_read_number(cache_size, 1);
216 return 0;
217}
218
219static int cache_size_kb(const struct cache *cache, unsigned int *ret)
220{
221 unsigned int size;
222
223 if (cache_size(cache, &size))
224 return -ENODEV;
225
226 *ret = size / 1024;
227 return 0;
228}
229
230/* not cache_line_size() because that's a macro in include/linux/cache.h */
231static int cache_get_line_size(const struct cache *cache, unsigned int *ret)
232{
233 const __be32 *line_size;
234 int i, lim;
235
236 lim = ARRAY_SIZE(cache_type_info[cache->type].line_size_props);
237
238 for (i = 0; i < lim; i++) {
239 const char *propname;
240
241 propname = cache_type_info[cache->type].line_size_props[i];
242 line_size = of_get_property(cache->ofnode, propname, NULL);
243 if (line_size)
244 break;
245 }
246
247 if (!line_size)
248 return -ENODEV;
249
250 *ret = of_read_number(line_size, 1);
251 return 0;
252}
253
254static int cache_nr_sets(const struct cache *cache, unsigned int *ret)
255{
256 const char *propname;
257 const __be32 *nr_sets;
258
259 propname = cache_type_info[cache->type].nr_sets_prop;
260
261 nr_sets = of_get_property(cache->ofnode, propname, NULL);
262 if (!nr_sets)
263 return -ENODEV;
264
265 *ret = of_read_number(nr_sets, 1);
266 return 0;
267}
268
269static int cache_associativity(const struct cache *cache, unsigned int *ret)
270{
271 unsigned int line_size;
272 unsigned int nr_sets;
273 unsigned int size;
274
275 if (cache_nr_sets(cache, &nr_sets))
276 goto err;
277
278 /* If the cache is fully associative, there is no need to
279 * check the other properties.
280 */
281 if (nr_sets == 1) {
282 *ret = 0;
283 return 0;
284 }
285
286 if (cache_get_line_size(cache, &line_size))
287 goto err;
288 if (cache_size(cache, &size))
289 goto err;
290
291 if (!(nr_sets > 0 && size > 0 && line_size > 0))
292 goto err;
293
294 *ret = (size / nr_sets) / line_size;
295 return 0;
296err:
297 return -ENODEV;
298}
299
300/* helper for dealing with split caches */
301static struct cache *cache_find_first_sibling(struct cache *cache)
302{
303 struct cache *iter;
304
305 if (cache->type == CACHE_TYPE_UNIFIED ||
306 cache->type == CACHE_TYPE_UNIFIED_D)
307 return cache;
308
309 list_for_each_entry(iter, &cache_list, list)
310 if (iter->ofnode == cache->ofnode && iter->next_local == cache)
311 return iter;
312
313 return cache;
314}
315
316/* return the first cache on a local list matching node */
317static struct cache *cache_lookup_by_node(const struct device_node *node)
318{
319 struct cache *cache = NULL;
320 struct cache *iter;
321
322 list_for_each_entry(iter, &cache_list, list) {
323 if (iter->ofnode != node)
324 continue;
325 cache = cache_find_first_sibling(iter);
326 break;
327 }
328
329 return cache;
330}
331
332static bool cache_node_is_unified(const struct device_node *np)
333{
334 return of_get_property(np, "cache-unified", NULL);
335}
336
337/*
338 * Unified caches can have two different sets of tags. Most embedded
339 * use cache-size, etc. for the unified cache size, but open firmware systems
340 * use d-cache-size, etc. Check on initialization for which type we have, and
341 * return the appropriate structure type. Assume it's embedded if it isn't
342 * open firmware. If it's yet a 3rd type, then there will be missing entries
343 * in /sys/devices/system/cpu/cpu0/cache/index2/, and this code will need
344 * to be extended further.
345 */
346static int cache_is_unified_d(const struct device_node *np)
347{
348 return of_get_property(np,
349 cache_type_info[CACHE_TYPE_UNIFIED_D].size_prop, NULL) ?
350 CACHE_TYPE_UNIFIED_D : CACHE_TYPE_UNIFIED;
351}
352
353static struct cache *cache_do_one_devnode_unified(struct device_node *node, int level)
354{
355 pr_debug("creating L%d ucache for %pOF\n", level, node);
356
357 return new_cache(cache_is_unified_d(node), level, node);
358}
359
360static struct cache *cache_do_one_devnode_split(struct device_node *node,
361 int level)
362{
363 struct cache *dcache, *icache;
364
365 pr_debug("creating L%d dcache and icache for %pOF\n", level,
366 node);
367
368 dcache = new_cache(CACHE_TYPE_DATA, level, node);
369 icache = new_cache(CACHE_TYPE_INSTRUCTION, level, node);
370
371 if (!dcache || !icache)
372 goto err;
373
374 dcache->next_local = icache;
375
376 return dcache;
377err:
378 release_cache(dcache);
379 release_cache(icache);
380 return NULL;
381}
382
383static struct cache *cache_do_one_devnode(struct device_node *node, int level)
384{
385 struct cache *cache;
386
387 if (cache_node_is_unified(node))
388 cache = cache_do_one_devnode_unified(node, level);
389 else
390 cache = cache_do_one_devnode_split(node, level);
391
392 return cache;
393}
394
395static struct cache *cache_lookup_or_instantiate(struct device_node *node,
396 int level)
397{
398 struct cache *cache;
399
400 cache = cache_lookup_by_node(node);
401
402 WARN_ONCE(cache && cache->level != level,
403 "cache level mismatch on lookup (got %d, expected %d)\n",
404 cache->level, level);
405
406 if (!cache)
407 cache = cache_do_one_devnode(node, level);
408
409 return cache;
410}
411
412static void link_cache_lists(struct cache *smaller, struct cache *bigger)
413{
414 while (smaller->next_local) {
415 if (smaller->next_local == bigger)
416 return; /* already linked */
417 smaller = smaller->next_local;
418 }
419
420 smaller->next_local = bigger;
421}
422
423static void do_subsidiary_caches_debugcheck(struct cache *cache)
424{
425 WARN_ON_ONCE(cache->level != 1);
426 WARN_ON_ONCE(!of_node_is_type(cache->ofnode, "cpu"));
427}
428
429static void do_subsidiary_caches(struct cache *cache)
430{
431 struct device_node *subcache_node;
432 int level = cache->level;
433
434 do_subsidiary_caches_debugcheck(cache);
435
436 while ((subcache_node = of_find_next_cache_node(cache->ofnode))) {
437 struct cache *subcache;
438
439 level++;
440 subcache = cache_lookup_or_instantiate(subcache_node, level);
441 of_node_put(subcache_node);
442 if (!subcache)
443 break;
444
445 link_cache_lists(cache, subcache);
446 cache = subcache;
447 }
448}
449
450static struct cache *cache_chain_instantiate(unsigned int cpu_id)
451{
452 struct device_node *cpu_node;
453 struct cache *cpu_cache = NULL;
454
455 pr_debug("creating cache object(s) for CPU %i\n", cpu_id);
456
457 cpu_node = of_get_cpu_node(cpu_id, NULL);
458 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
459 if (!cpu_node)
460 goto out;
461
462 cpu_cache = cache_lookup_or_instantiate(cpu_node, 1);
463 if (!cpu_cache)
464 goto out;
465
466 do_subsidiary_caches(cpu_cache);
467
468 cache_cpu_set(cpu_cache, cpu_id);
469out:
470 of_node_put(cpu_node);
471
472 return cpu_cache;
473}
474
475static struct cache_dir *cacheinfo_create_cache_dir(unsigned int cpu_id)
476{
477 struct cache_dir *cache_dir;
478 struct device *dev;
479 struct kobject *kobj = NULL;
480
481 dev = get_cpu_device(cpu_id);
482 WARN_ONCE(!dev, "no dev for CPU %i\n", cpu_id);
483 if (!dev)
484 goto err;
485
486 kobj = kobject_create_and_add("cache", &dev->kobj);
487 if (!kobj)
488 goto err;
489
490 cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
491 if (!cache_dir)
492 goto err;
493
494 cache_dir->kobj = kobj;
495
496 WARN_ON_ONCE(per_cpu(cache_dir_pcpu, cpu_id) != NULL);
497
498 per_cpu(cache_dir_pcpu, cpu_id) = cache_dir;
499
500 return cache_dir;
501err:
502 kobject_put(kobj);
503 return NULL;
504}
505
506static void cache_index_release(struct kobject *kobj)
507{
508 struct cache_index_dir *index;
509
510 index = kobj_to_cache_index_dir(kobj);
511
512 pr_debug("freeing index directory for L%d %s cache\n",
513 index->cache->level, cache_type_string(index->cache));
514
515 kfree(index);
516}
517
518static ssize_t cache_index_show(struct kobject *k, struct attribute *attr, char *buf)
519{
520 struct kobj_attribute *kobj_attr;
521
522 kobj_attr = container_of(attr, struct kobj_attribute, attr);
523
524 return kobj_attr->show(k, kobj_attr, buf);
525}
526
527static struct cache *index_kobj_to_cache(struct kobject *k)
528{
529 struct cache_index_dir *index;
530
531 index = kobj_to_cache_index_dir(k);
532
533 return index->cache;
534}
535
536static ssize_t size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
537{
538 unsigned int size_kb;
539 struct cache *cache;
540
541 cache = index_kobj_to_cache(k);
542
543 if (cache_size_kb(cache, &size_kb))
544 return -ENODEV;
545
546 return sprintf(buf, "%uK\n", size_kb);
547}
548
549static struct kobj_attribute cache_size_attr =
550 __ATTR(size, 0444, size_show, NULL);
551
552
553static ssize_t line_size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
554{
555 unsigned int line_size;
556 struct cache *cache;
557
558 cache = index_kobj_to_cache(k);
559
560 if (cache_get_line_size(cache, &line_size))
561 return -ENODEV;
562
563 return sprintf(buf, "%u\n", line_size);
564}
565
566static struct kobj_attribute cache_line_size_attr =
567 __ATTR(coherency_line_size, 0444, line_size_show, NULL);
568
569static ssize_t nr_sets_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
570{
571 unsigned int nr_sets;
572 struct cache *cache;
573
574 cache = index_kobj_to_cache(k);
575
576 if (cache_nr_sets(cache, &nr_sets))
577 return -ENODEV;
578
579 return sprintf(buf, "%u\n", nr_sets);
580}
581
582static struct kobj_attribute cache_nr_sets_attr =
583 __ATTR(number_of_sets, 0444, nr_sets_show, NULL);
584
585static ssize_t associativity_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
586{
587 unsigned int associativity;
588 struct cache *cache;
589
590 cache = index_kobj_to_cache(k);
591
592 if (cache_associativity(cache, &associativity))
593 return -ENODEV;
594
595 return sprintf(buf, "%u\n", associativity);
596}
597
598static struct kobj_attribute cache_assoc_attr =
599 __ATTR(ways_of_associativity, 0444, associativity_show, NULL);
600
601static ssize_t type_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
602{
603 struct cache *cache;
604
605 cache = index_kobj_to_cache(k);
606
607 return sprintf(buf, "%s\n", cache_type_string(cache));
608}
609
610static struct kobj_attribute cache_type_attr =
611 __ATTR(type, 0444, type_show, NULL);
612
613static ssize_t level_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
614{
615 struct cache_index_dir *index;
616 struct cache *cache;
617
618 index = kobj_to_cache_index_dir(k);
619 cache = index->cache;
620
621 return sprintf(buf, "%d\n", cache->level);
622}
623
624static struct kobj_attribute cache_level_attr =
625 __ATTR(level, 0444, level_show, NULL);
626
627static unsigned int index_dir_to_cpu(struct cache_index_dir *index)
628{
629 struct kobject *index_dir_kobj = &index->kobj;
630 struct kobject *cache_dir_kobj = index_dir_kobj->parent;
631 struct kobject *cpu_dev_kobj = cache_dir_kobj->parent;
632 struct device *dev = kobj_to_dev(cpu_dev_kobj);
633
634 return dev->id;
635}
636
637/*
638 * On big-core systems, each core has two groups of CPUs each of which
639 * has its own L1-cache. The thread-siblings which share l1-cache with
640 * @cpu can be obtained via cpu_smallcore_mask().
641 */
642static const struct cpumask *get_big_core_shared_cpu_map(int cpu, struct cache *cache)
643{
644 if (cache->level == 1)
645 return cpu_smallcore_mask(cpu);
646
647 return &cache->shared_cpu_map;
648}
649
650static ssize_t shared_cpu_map_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
651{
652 struct cache_index_dir *index;
653 struct cache *cache;
654 const struct cpumask *mask;
655 int ret, cpu;
656
657 index = kobj_to_cache_index_dir(k);
658 cache = index->cache;
659
660 if (has_big_cores) {
661 cpu = index_dir_to_cpu(index);
662 mask = get_big_core_shared_cpu_map(cpu, cache);
663 } else {
664 mask = &cache->shared_cpu_map;
665 }
666
667 ret = scnprintf(buf, PAGE_SIZE - 1, "%*pb\n",
668 cpumask_pr_args(mask));
669 buf[ret++] = '\n';
670 buf[ret] = '\0';
671 return ret;
672}
673
674static struct kobj_attribute cache_shared_cpu_map_attr =
675 __ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);
676
677/* Attributes which should always be created -- the kobject/sysfs core
678 * does this automatically via kobj_type->default_attrs. This is the
679 * minimum data required to uniquely identify a cache.
680 */
681static struct attribute *cache_index_default_attrs[] = {
682 &cache_type_attr.attr,
683 &cache_level_attr.attr,
684 &cache_shared_cpu_map_attr.attr,
685 NULL,
686};
687
688/* Attributes which should be created if the cache device node has the
689 * right properties -- see cacheinfo_create_index_opt_attrs
690 */
691static struct kobj_attribute *cache_index_opt_attrs[] = {
692 &cache_size_attr,
693 &cache_line_size_attr,
694 &cache_nr_sets_attr,
695 &cache_assoc_attr,
696};
697
698static const struct sysfs_ops cache_index_ops = {
699 .show = cache_index_show,
700};
701
702static struct kobj_type cache_index_type = {
703 .release = cache_index_release,
704 .sysfs_ops = &cache_index_ops,
705 .default_attrs = cache_index_default_attrs,
706};
707
708static void cacheinfo_create_index_opt_attrs(struct cache_index_dir *dir)
709{
710 const char *cache_type;
711 struct cache *cache;
712 char *buf;
713 int i;
714
715 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
716 if (!buf)
717 return;
718
719 cache = dir->cache;
720 cache_type = cache_type_string(cache);
721
722 /* We don't want to create an attribute that can't provide a
723 * meaningful value. Check the return value of each optional
724 * attribute's ->show method before registering the
725 * attribute.
726 */
727 for (i = 0; i < ARRAY_SIZE(cache_index_opt_attrs); i++) {
728 struct kobj_attribute *attr;
729 ssize_t rc;
730
731 attr = cache_index_opt_attrs[i];
732
733 rc = attr->show(&dir->kobj, attr, buf);
734 if (rc <= 0) {
735 pr_debug("not creating %s attribute for "
736 "%pOF(%s) (rc = %zd)\n",
737 attr->attr.name, cache->ofnode,
738 cache_type, rc);
739 continue;
740 }
741 if (sysfs_create_file(&dir->kobj, &attr->attr))
742 pr_debug("could not create %s attribute for %pOF(%s)\n",
743 attr->attr.name, cache->ofnode, cache_type);
744 }
745
746 kfree(buf);
747}
748
749static void cacheinfo_create_index_dir(struct cache *cache, int index,
750 struct cache_dir *cache_dir)
751{
752 struct cache_index_dir *index_dir;
753 int rc;
754
755 index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
756 if (!index_dir)
757 return;
758
759 index_dir->cache = cache;
760
761 rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
762 cache_dir->kobj, "index%d", index);
763 if (rc) {
764 kobject_put(&index_dir->kobj);
765 return;
766 }
767
768 index_dir->next = cache_dir->index;
769 cache_dir->index = index_dir;
770
771 cacheinfo_create_index_opt_attrs(index_dir);
772}
773
774static void cacheinfo_sysfs_populate(unsigned int cpu_id,
775 struct cache *cache_list)
776{
777 struct cache_dir *cache_dir;
778 struct cache *cache;
779 int index = 0;
780
781 cache_dir = cacheinfo_create_cache_dir(cpu_id);
782 if (!cache_dir)
783 return;
784
785 cache = cache_list;
786 while (cache) {
787 cacheinfo_create_index_dir(cache, index, cache_dir);
788 index++;
789 cache = cache->next_local;
790 }
791}
792
793void cacheinfo_cpu_online(unsigned int cpu_id)
794{
795 struct cache *cache;
796
797 cache = cache_chain_instantiate(cpu_id);
798 if (!cache)
799 return;
800
801 cacheinfo_sysfs_populate(cpu_id, cache);
802}
803
804/* functions needed to remove cache entry for cpu offline or suspend/resume */
805
806#if (defined(CONFIG_PPC_PSERIES) && defined(CONFIG_SUSPEND)) || \
807 defined(CONFIG_HOTPLUG_CPU)
808
809static struct cache *cache_lookup_by_cpu(unsigned int cpu_id)
810{
811 struct device_node *cpu_node;
812 struct cache *cache;
813
814 cpu_node = of_get_cpu_node(cpu_id, NULL);
815 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
816 if (!cpu_node)
817 return NULL;
818
819 cache = cache_lookup_by_node(cpu_node);
820 of_node_put(cpu_node);
821
822 return cache;
823}
824
825static void remove_index_dirs(struct cache_dir *cache_dir)
826{
827 struct cache_index_dir *index;
828
829 index = cache_dir->index;
830
831 while (index) {
832 struct cache_index_dir *next;
833
834 next = index->next;
835 kobject_put(&index->kobj);
836 index = next;
837 }
838}
839
840static void remove_cache_dir(struct cache_dir *cache_dir)
841{
842 remove_index_dirs(cache_dir);
843
844 /* Remove cache dir from sysfs */
845 kobject_del(cache_dir->kobj);
846
847 kobject_put(cache_dir->kobj);
848
849 kfree(cache_dir);
850}
851
852static void cache_cpu_clear(struct cache *cache, int cpu)
853{
854 while (cache) {
855 struct cache *next = cache->next_local;
856
857 WARN_ONCE(!cpumask_test_cpu(cpu, &cache->shared_cpu_map),
858 "CPU %i not accounted in %pOF(%s)\n",
859 cpu, cache->ofnode,
860 cache_type_string(cache));
861
862 cpumask_clear_cpu(cpu, &cache->shared_cpu_map);
863
864 /* Release the cache object if all the cpus using it
865 * are offline */
866 if (cpumask_empty(&cache->shared_cpu_map))
867 release_cache(cache);
868
869 cache = next;
870 }
871}
872
873void cacheinfo_cpu_offline(unsigned int cpu_id)
874{
875 struct cache_dir *cache_dir;
876 struct cache *cache;
877
878 /* Prevent userspace from seeing inconsistent state - remove
879 * the sysfs hierarchy first */
880 cache_dir = per_cpu(cache_dir_pcpu, cpu_id);
881
882 /* careful, sysfs population may have failed */
883 if (cache_dir)
884 remove_cache_dir(cache_dir);
885
886 per_cpu(cache_dir_pcpu, cpu_id) = NULL;
887
888 /* clear the CPU's bit in its cache chain, possibly freeing
889 * cache objects */
890 cache = cache_lookup_by_cpu(cpu_id);
891 if (cache)
892 cache_cpu_clear(cache, cpu_id);
893}
894
895void cacheinfo_teardown(void)
896{
897 unsigned int cpu;
898
899 lockdep_assert_cpus_held();
900
901 for_each_online_cpu(cpu)
902 cacheinfo_cpu_offline(cpu);
903}
904
905void cacheinfo_rebuild(void)
906{
907 unsigned int cpu;
908
909 lockdep_assert_cpus_held();
910
911 for_each_online_cpu(cpu)
912 cacheinfo_cpu_online(cpu);
913}
914
915#endif /* (CONFIG_PPC_PSERIES && CONFIG_SUSPEND) || CONFIG_HOTPLUG_CPU */