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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#define pr_fmt(fmt) "cacheinfo: " fmt
11
12#include <linux/cpu.h>
13#include <linux/cpumask.h>
14#include <linux/kernel.h>
15#include <linux/kobject.h>
16#include <linux/list.h>
17#include <linux/notifier.h>
18#include <linux/of.h>
19#include <linux/percpu.h>
20#include <linux/slab.h>
21#include <asm/cputhreads.h>
22#include <asm/smp.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 int group_id; /* id of the group of threads that share this cache */
123 struct list_head list; /* global list of cache objects */
124 struct cache *next_local; /* next cache of >= level */
125};
126
127static DEFINE_PER_CPU(struct cache_dir *, cache_dir_pcpu);
128
129/* traversal/modification of this list occurs only at cpu hotplug time;
130 * access is serialized by cpu hotplug locking
131 */
132static LIST_HEAD(cache_list);
133
134static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *k)
135{
136 return container_of(k, struct cache_index_dir, kobj);
137}
138
139static const char *cache_type_string(const struct cache *cache)
140{
141 return cache_type_info[cache->type].name;
142}
143
144static void cache_init(struct cache *cache, int type, int level,
145 struct device_node *ofnode, int group_id)
146{
147 cache->type = type;
148 cache->level = level;
149 cache->ofnode = of_node_get(ofnode);
150 cache->group_id = group_id;
151 INIT_LIST_HEAD(&cache->list);
152 list_add(&cache->list, &cache_list);
153}
154
155static struct cache *new_cache(int type, int level,
156 struct device_node *ofnode, int group_id)
157{
158 struct cache *cache;
159
160 cache = kzalloc(sizeof(*cache), GFP_KERNEL);
161 if (cache)
162 cache_init(cache, type, level, ofnode, group_id);
163
164 return cache;
165}
166
167static void release_cache_debugcheck(struct cache *cache)
168{
169 struct cache *iter;
170
171 list_for_each_entry(iter, &cache_list, list)
172 WARN_ONCE(iter->next_local == cache,
173 "cache for %pOFP(%s) refers to cache for %pOFP(%s)\n",
174 iter->ofnode,
175 cache_type_string(iter),
176 cache->ofnode,
177 cache_type_string(cache));
178}
179
180static void release_cache(struct cache *cache)
181{
182 if (!cache)
183 return;
184
185 pr_debug("freeing L%d %s cache for %pOFP\n", cache->level,
186 cache_type_string(cache), cache->ofnode);
187
188 release_cache_debugcheck(cache);
189 list_del(&cache->list);
190 of_node_put(cache->ofnode);
191 kfree(cache);
192}
193
194static void cache_cpu_set(struct cache *cache, int cpu)
195{
196 struct cache *next = cache;
197
198 while (next) {
199 WARN_ONCE(cpumask_test_cpu(cpu, &next->shared_cpu_map),
200 "CPU %i already accounted in %pOFP(%s)\n",
201 cpu, next->ofnode,
202 cache_type_string(next));
203 cpumask_set_cpu(cpu, &next->shared_cpu_map);
204 next = next->next_local;
205 }
206}
207
208static int cache_size(const struct cache *cache, unsigned int *ret)
209{
210 const char *propname;
211 const __be32 *cache_size;
212
213 propname = cache_type_info[cache->type].size_prop;
214
215 cache_size = of_get_property(cache->ofnode, propname, NULL);
216 if (!cache_size)
217 return -ENODEV;
218
219 *ret = of_read_number(cache_size, 1);
220 return 0;
221}
222
223static int cache_size_kb(const struct cache *cache, unsigned int *ret)
224{
225 unsigned int size;
226
227 if (cache_size(cache, &size))
228 return -ENODEV;
229
230 *ret = size / 1024;
231 return 0;
232}
233
234/* not cache_line_size() because that's a macro in include/linux/cache.h */
235static int cache_get_line_size(const struct cache *cache, unsigned int *ret)
236{
237 const __be32 *line_size;
238 int i, lim;
239
240 lim = ARRAY_SIZE(cache_type_info[cache->type].line_size_props);
241
242 for (i = 0; i < lim; i++) {
243 const char *propname;
244
245 propname = cache_type_info[cache->type].line_size_props[i];
246 line_size = of_get_property(cache->ofnode, propname, NULL);
247 if (line_size)
248 break;
249 }
250
251 if (!line_size)
252 return -ENODEV;
253
254 *ret = of_read_number(line_size, 1);
255 return 0;
256}
257
258static int cache_nr_sets(const struct cache *cache, unsigned int *ret)
259{
260 const char *propname;
261 const __be32 *nr_sets;
262
263 propname = cache_type_info[cache->type].nr_sets_prop;
264
265 nr_sets = of_get_property(cache->ofnode, propname, NULL);
266 if (!nr_sets)
267 return -ENODEV;
268
269 *ret = of_read_number(nr_sets, 1);
270 return 0;
271}
272
273static int cache_associativity(const struct cache *cache, unsigned int *ret)
274{
275 unsigned int line_size;
276 unsigned int nr_sets;
277 unsigned int size;
278
279 if (cache_nr_sets(cache, &nr_sets))
280 goto err;
281
282 /* If the cache is fully associative, there is no need to
283 * check the other properties.
284 */
285 if (nr_sets == 1) {
286 *ret = 0;
287 return 0;
288 }
289
290 if (cache_get_line_size(cache, &line_size))
291 goto err;
292 if (cache_size(cache, &size))
293 goto err;
294
295 if (!(nr_sets > 0 && size > 0 && line_size > 0))
296 goto err;
297
298 *ret = (size / nr_sets) / line_size;
299 return 0;
300err:
301 return -ENODEV;
302}
303
304/* helper for dealing with split caches */
305static struct cache *cache_find_first_sibling(struct cache *cache)
306{
307 struct cache *iter;
308
309 if (cache->type == CACHE_TYPE_UNIFIED ||
310 cache->type == CACHE_TYPE_UNIFIED_D)
311 return cache;
312
313 list_for_each_entry(iter, &cache_list, list)
314 if (iter->ofnode == cache->ofnode &&
315 iter->group_id == cache->group_id &&
316 iter->next_local == cache)
317 return iter;
318
319 return cache;
320}
321
322/* return the first cache on a local list matching node and thread-group id */
323static struct cache *cache_lookup_by_node_group(const struct device_node *node,
324 int group_id)
325{
326 struct cache *cache = NULL;
327 struct cache *iter;
328
329 list_for_each_entry(iter, &cache_list, list) {
330 if (iter->ofnode != node ||
331 iter->group_id != group_id)
332 continue;
333 cache = cache_find_first_sibling(iter);
334 break;
335 }
336
337 return cache;
338}
339
340static bool cache_node_is_unified(const struct device_node *np)
341{
342 return of_get_property(np, "cache-unified", NULL);
343}
344
345/*
346 * Unified caches can have two different sets of tags. Most embedded
347 * use cache-size, etc. for the unified cache size, but open firmware systems
348 * use d-cache-size, etc. Check on initialization for which type we have, and
349 * return the appropriate structure type. Assume it's embedded if it isn't
350 * open firmware. If it's yet a 3rd type, then there will be missing entries
351 * in /sys/devices/system/cpu/cpu0/cache/index2/, and this code will need
352 * to be extended further.
353 */
354static int cache_is_unified_d(const struct device_node *np)
355{
356 return of_get_property(np,
357 cache_type_info[CACHE_TYPE_UNIFIED_D].size_prop, NULL) ?
358 CACHE_TYPE_UNIFIED_D : CACHE_TYPE_UNIFIED;
359}
360
361static struct cache *cache_do_one_devnode_unified(struct device_node *node, int group_id,
362 int level)
363{
364 pr_debug("creating L%d ucache for %pOFP\n", level, node);
365
366 return new_cache(cache_is_unified_d(node), level, node, group_id);
367}
368
369static struct cache *cache_do_one_devnode_split(struct device_node *node, int group_id,
370 int level)
371{
372 struct cache *dcache, *icache;
373
374 pr_debug("creating L%d dcache and icache for %pOFP\n", level,
375 node);
376
377 dcache = new_cache(CACHE_TYPE_DATA, level, node, group_id);
378 icache = new_cache(CACHE_TYPE_INSTRUCTION, level, node, group_id);
379
380 if (!dcache || !icache)
381 goto err;
382
383 dcache->next_local = icache;
384
385 return dcache;
386err:
387 release_cache(dcache);
388 release_cache(icache);
389 return NULL;
390}
391
392static struct cache *cache_do_one_devnode(struct device_node *node, int group_id, int level)
393{
394 struct cache *cache;
395
396 if (cache_node_is_unified(node))
397 cache = cache_do_one_devnode_unified(node, group_id, level);
398 else
399 cache = cache_do_one_devnode_split(node, group_id, level);
400
401 return cache;
402}
403
404static struct cache *cache_lookup_or_instantiate(struct device_node *node,
405 int group_id,
406 int level)
407{
408 struct cache *cache;
409
410 cache = cache_lookup_by_node_group(node, group_id);
411
412 WARN_ONCE(cache && cache->level != level,
413 "cache level mismatch on lookup (got %d, expected %d)\n",
414 cache->level, level);
415
416 if (!cache)
417 cache = cache_do_one_devnode(node, group_id, level);
418
419 return cache;
420}
421
422static void link_cache_lists(struct cache *smaller, struct cache *bigger)
423{
424 while (smaller->next_local) {
425 if (smaller->next_local == bigger)
426 return; /* already linked */
427 smaller = smaller->next_local;
428 }
429
430 smaller->next_local = bigger;
431
432 /*
433 * The cache->next_local list sorts by level ascending:
434 * L1d -> L1i -> L2 -> L3 ...
435 */
436 WARN_ONCE((smaller->level == 1 && bigger->level > 2) ||
437 (smaller->level > 1 && bigger->level != smaller->level + 1),
438 "linking L%i cache %pOFP to L%i cache %pOFP; skipped a level?\n",
439 smaller->level, smaller->ofnode, bigger->level, bigger->ofnode);
440}
441
442static void do_subsidiary_caches_debugcheck(struct cache *cache)
443{
444 WARN_ONCE(cache->level != 1,
445 "instantiating cache chain from L%d %s cache for "
446 "%pOFP instead of an L1\n", cache->level,
447 cache_type_string(cache), cache->ofnode);
448 WARN_ONCE(!of_node_is_type(cache->ofnode, "cpu"),
449 "instantiating cache chain from node %pOFP of type '%s' "
450 "instead of a cpu node\n", cache->ofnode,
451 of_node_get_device_type(cache->ofnode));
452}
453
454/*
455 * If sub-groups of threads in a core containing @cpu_id share the
456 * L@level-cache (information obtained via "ibm,thread-groups"
457 * device-tree property), then we identify the group by the first
458 * thread-sibling in the group. We define this to be the group-id.
459 *
460 * In the absence of any thread-group information for L@level-cache,
461 * this function returns -1.
462 */
463static int get_group_id(unsigned int cpu_id, int level)
464{
465 if (has_big_cores && level == 1)
466 return cpumask_first(per_cpu(thread_group_l1_cache_map,
467 cpu_id));
468 else if (thread_group_shares_l2 && level == 2)
469 return cpumask_first(per_cpu(thread_group_l2_cache_map,
470 cpu_id));
471 else if (thread_group_shares_l3 && level == 3)
472 return cpumask_first(per_cpu(thread_group_l3_cache_map,
473 cpu_id));
474 return -1;
475}
476
477static void do_subsidiary_caches(struct cache *cache, unsigned int cpu_id)
478{
479 struct device_node *subcache_node;
480 int level = cache->level;
481
482 do_subsidiary_caches_debugcheck(cache);
483
484 while ((subcache_node = of_find_next_cache_node(cache->ofnode))) {
485 struct cache *subcache;
486 int group_id;
487
488 level++;
489 group_id = get_group_id(cpu_id, level);
490 subcache = cache_lookup_or_instantiate(subcache_node, group_id, level);
491 of_node_put(subcache_node);
492 if (!subcache)
493 break;
494
495 link_cache_lists(cache, subcache);
496 cache = subcache;
497 }
498}
499
500static struct cache *cache_chain_instantiate(unsigned int cpu_id)
501{
502 struct device_node *cpu_node;
503 struct cache *cpu_cache = NULL;
504 int group_id;
505
506 pr_debug("creating cache object(s) for CPU %i\n", cpu_id);
507
508 cpu_node = of_get_cpu_node(cpu_id, NULL);
509 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
510 if (!cpu_node)
511 goto out;
512
513 group_id = get_group_id(cpu_id, 1);
514
515 cpu_cache = cache_lookup_or_instantiate(cpu_node, group_id, 1);
516 if (!cpu_cache)
517 goto out;
518
519 do_subsidiary_caches(cpu_cache, cpu_id);
520
521 cache_cpu_set(cpu_cache, cpu_id);
522out:
523 of_node_put(cpu_node);
524
525 return cpu_cache;
526}
527
528static struct cache_dir *cacheinfo_create_cache_dir(unsigned int cpu_id)
529{
530 struct cache_dir *cache_dir;
531 struct device *dev;
532 struct kobject *kobj = NULL;
533
534 dev = get_cpu_device(cpu_id);
535 WARN_ONCE(!dev, "no dev for CPU %i\n", cpu_id);
536 if (!dev)
537 goto err;
538
539 kobj = kobject_create_and_add("cache", &dev->kobj);
540 if (!kobj)
541 goto err;
542
543 cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
544 if (!cache_dir)
545 goto err;
546
547 cache_dir->kobj = kobj;
548
549 WARN_ON_ONCE(per_cpu(cache_dir_pcpu, cpu_id) != NULL);
550
551 per_cpu(cache_dir_pcpu, cpu_id) = cache_dir;
552
553 return cache_dir;
554err:
555 kobject_put(kobj);
556 return NULL;
557}
558
559static void cache_index_release(struct kobject *kobj)
560{
561 struct cache_index_dir *index;
562
563 index = kobj_to_cache_index_dir(kobj);
564
565 pr_debug("freeing index directory for L%d %s cache\n",
566 index->cache->level, cache_type_string(index->cache));
567
568 kfree(index);
569}
570
571static ssize_t cache_index_show(struct kobject *k, struct attribute *attr, char *buf)
572{
573 struct kobj_attribute *kobj_attr;
574
575 kobj_attr = container_of(attr, struct kobj_attribute, attr);
576
577 return kobj_attr->show(k, kobj_attr, buf);
578}
579
580static struct cache *index_kobj_to_cache(struct kobject *k)
581{
582 struct cache_index_dir *index;
583
584 index = kobj_to_cache_index_dir(k);
585
586 return index->cache;
587}
588
589static ssize_t size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
590{
591 unsigned int size_kb;
592 struct cache *cache;
593
594 cache = index_kobj_to_cache(k);
595
596 if (cache_size_kb(cache, &size_kb))
597 return -ENODEV;
598
599 return sprintf(buf, "%uK\n", size_kb);
600}
601
602static struct kobj_attribute cache_size_attr =
603 __ATTR(size, 0444, size_show, NULL);
604
605
606static ssize_t line_size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
607{
608 unsigned int line_size;
609 struct cache *cache;
610
611 cache = index_kobj_to_cache(k);
612
613 if (cache_get_line_size(cache, &line_size))
614 return -ENODEV;
615
616 return sprintf(buf, "%u\n", line_size);
617}
618
619static struct kobj_attribute cache_line_size_attr =
620 __ATTR(coherency_line_size, 0444, line_size_show, NULL);
621
622static ssize_t nr_sets_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
623{
624 unsigned int nr_sets;
625 struct cache *cache;
626
627 cache = index_kobj_to_cache(k);
628
629 if (cache_nr_sets(cache, &nr_sets))
630 return -ENODEV;
631
632 return sprintf(buf, "%u\n", nr_sets);
633}
634
635static struct kobj_attribute cache_nr_sets_attr =
636 __ATTR(number_of_sets, 0444, nr_sets_show, NULL);
637
638static ssize_t associativity_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
639{
640 unsigned int associativity;
641 struct cache *cache;
642
643 cache = index_kobj_to_cache(k);
644
645 if (cache_associativity(cache, &associativity))
646 return -ENODEV;
647
648 return sprintf(buf, "%u\n", associativity);
649}
650
651static struct kobj_attribute cache_assoc_attr =
652 __ATTR(ways_of_associativity, 0444, associativity_show, NULL);
653
654static ssize_t type_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
655{
656 struct cache *cache;
657
658 cache = index_kobj_to_cache(k);
659
660 return sprintf(buf, "%s\n", cache_type_string(cache));
661}
662
663static struct kobj_attribute cache_type_attr =
664 __ATTR(type, 0444, type_show, NULL);
665
666static ssize_t level_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
667{
668 struct cache_index_dir *index;
669 struct cache *cache;
670
671 index = kobj_to_cache_index_dir(k);
672 cache = index->cache;
673
674 return sprintf(buf, "%d\n", cache->level);
675}
676
677static struct kobj_attribute cache_level_attr =
678 __ATTR(level, 0444, level_show, NULL);
679
680static ssize_t
681show_shared_cpumap(struct kobject *k, struct kobj_attribute *attr, char *buf, bool list)
682{
683 struct cache_index_dir *index;
684 struct cache *cache;
685 const struct cpumask *mask;
686
687 index = kobj_to_cache_index_dir(k);
688 cache = index->cache;
689
690 mask = &cache->shared_cpu_map;
691
692 return cpumap_print_to_pagebuf(list, buf, mask);
693}
694
695static ssize_t shared_cpu_map_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
696{
697 return show_shared_cpumap(k, attr, buf, false);
698}
699
700static ssize_t shared_cpu_list_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
701{
702 return show_shared_cpumap(k, attr, buf, true);
703}
704
705static struct kobj_attribute cache_shared_cpu_map_attr =
706 __ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);
707
708static struct kobj_attribute cache_shared_cpu_list_attr =
709 __ATTR(shared_cpu_list, 0444, shared_cpu_list_show, NULL);
710
711/* Attributes which should always be created -- the kobject/sysfs core
712 * does this automatically via kobj_type->default_groups. This is the
713 * minimum data required to uniquely identify a cache.
714 */
715static struct attribute *cache_index_default_attrs[] = {
716 &cache_type_attr.attr,
717 &cache_level_attr.attr,
718 &cache_shared_cpu_map_attr.attr,
719 &cache_shared_cpu_list_attr.attr,
720 NULL,
721};
722ATTRIBUTE_GROUPS(cache_index_default);
723
724/* Attributes which should be created if the cache device node has the
725 * right properties -- see cacheinfo_create_index_opt_attrs
726 */
727static struct kobj_attribute *cache_index_opt_attrs[] = {
728 &cache_size_attr,
729 &cache_line_size_attr,
730 &cache_nr_sets_attr,
731 &cache_assoc_attr,
732};
733
734static const struct sysfs_ops cache_index_ops = {
735 .show = cache_index_show,
736};
737
738static struct kobj_type cache_index_type = {
739 .release = cache_index_release,
740 .sysfs_ops = &cache_index_ops,
741 .default_groups = cache_index_default_groups,
742};
743
744static void cacheinfo_create_index_opt_attrs(struct cache_index_dir *dir)
745{
746 const char *cache_type;
747 struct cache *cache;
748 char *buf;
749 int i;
750
751 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
752 if (!buf)
753 return;
754
755 cache = dir->cache;
756 cache_type = cache_type_string(cache);
757
758 /* We don't want to create an attribute that can't provide a
759 * meaningful value. Check the return value of each optional
760 * attribute's ->show method before registering the
761 * attribute.
762 */
763 for (i = 0; i < ARRAY_SIZE(cache_index_opt_attrs); i++) {
764 struct kobj_attribute *attr;
765 ssize_t rc;
766
767 attr = cache_index_opt_attrs[i];
768
769 rc = attr->show(&dir->kobj, attr, buf);
770 if (rc <= 0) {
771 pr_debug("not creating %s attribute for "
772 "%pOFP(%s) (rc = %zd)\n",
773 attr->attr.name, cache->ofnode,
774 cache_type, rc);
775 continue;
776 }
777 if (sysfs_create_file(&dir->kobj, &attr->attr))
778 pr_debug("could not create %s attribute for %pOFP(%s)\n",
779 attr->attr.name, cache->ofnode, cache_type);
780 }
781
782 kfree(buf);
783}
784
785static void cacheinfo_create_index_dir(struct cache *cache, int index,
786 struct cache_dir *cache_dir)
787{
788 struct cache_index_dir *index_dir;
789 int rc;
790
791 index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
792 if (!index_dir)
793 return;
794
795 index_dir->cache = cache;
796
797 rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
798 cache_dir->kobj, "index%d", index);
799 if (rc) {
800 kobject_put(&index_dir->kobj);
801 return;
802 }
803
804 index_dir->next = cache_dir->index;
805 cache_dir->index = index_dir;
806
807 cacheinfo_create_index_opt_attrs(index_dir);
808}
809
810static void cacheinfo_sysfs_populate(unsigned int cpu_id,
811 struct cache *cache_list)
812{
813 struct cache_dir *cache_dir;
814 struct cache *cache;
815 int index = 0;
816
817 cache_dir = cacheinfo_create_cache_dir(cpu_id);
818 if (!cache_dir)
819 return;
820
821 cache = cache_list;
822 while (cache) {
823 cacheinfo_create_index_dir(cache, index, cache_dir);
824 index++;
825 cache = cache->next_local;
826 }
827}
828
829void cacheinfo_cpu_online(unsigned int cpu_id)
830{
831 struct cache *cache;
832
833 cache = cache_chain_instantiate(cpu_id);
834 if (!cache)
835 return;
836
837 cacheinfo_sysfs_populate(cpu_id, cache);
838}
839
840/* functions needed to remove cache entry for cpu offline or suspend/resume */
841
842#if (defined(CONFIG_PPC_PSERIES) && defined(CONFIG_SUSPEND)) || \
843 defined(CONFIG_HOTPLUG_CPU)
844
845static struct cache *cache_lookup_by_cpu(unsigned int cpu_id)
846{
847 struct device_node *cpu_node;
848 struct cache *cache;
849 int group_id;
850
851 cpu_node = of_get_cpu_node(cpu_id, NULL);
852 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
853 if (!cpu_node)
854 return NULL;
855
856 group_id = get_group_id(cpu_id, 1);
857 cache = cache_lookup_by_node_group(cpu_node, group_id);
858 of_node_put(cpu_node);
859
860 return cache;
861}
862
863static void remove_index_dirs(struct cache_dir *cache_dir)
864{
865 struct cache_index_dir *index;
866
867 index = cache_dir->index;
868
869 while (index) {
870 struct cache_index_dir *next;
871
872 next = index->next;
873 kobject_put(&index->kobj);
874 index = next;
875 }
876}
877
878static void remove_cache_dir(struct cache_dir *cache_dir)
879{
880 remove_index_dirs(cache_dir);
881
882 /* Remove cache dir from sysfs */
883 kobject_del(cache_dir->kobj);
884
885 kobject_put(cache_dir->kobj);
886
887 kfree(cache_dir);
888}
889
890static void cache_cpu_clear(struct cache *cache, int cpu)
891{
892 while (cache) {
893 struct cache *next = cache->next_local;
894
895 WARN_ONCE(!cpumask_test_cpu(cpu, &cache->shared_cpu_map),
896 "CPU %i not accounted in %pOFP(%s)\n",
897 cpu, cache->ofnode,
898 cache_type_string(cache));
899
900 cpumask_clear_cpu(cpu, &cache->shared_cpu_map);
901
902 /* Release the cache object if all the cpus using it
903 * are offline */
904 if (cpumask_empty(&cache->shared_cpu_map))
905 release_cache(cache);
906
907 cache = next;
908 }
909}
910
911void cacheinfo_cpu_offline(unsigned int cpu_id)
912{
913 struct cache_dir *cache_dir;
914 struct cache *cache;
915
916 /* Prevent userspace from seeing inconsistent state - remove
917 * the sysfs hierarchy first */
918 cache_dir = per_cpu(cache_dir_pcpu, cpu_id);
919
920 /* careful, sysfs population may have failed */
921 if (cache_dir)
922 remove_cache_dir(cache_dir);
923
924 per_cpu(cache_dir_pcpu, cpu_id) = NULL;
925
926 /* clear the CPU's bit in its cache chain, possibly freeing
927 * cache objects */
928 cache = cache_lookup_by_cpu(cpu_id);
929 if (cache)
930 cache_cpu_clear(cache, cpu_id);
931}
932
933void cacheinfo_teardown(void)
934{
935 unsigned int cpu;
936
937 lockdep_assert_cpus_held();
938
939 for_each_online_cpu(cpu)
940 cacheinfo_cpu_offline(cpu);
941}
942
943void cacheinfo_rebuild(void)
944{
945 unsigned int cpu;
946
947 lockdep_assert_cpus_held();
948
949 for_each_online_cpu(cpu)
950 cacheinfo_cpu_online(cpu);
951}
952
953#endif /* (CONFIG_PPC_PSERIES && CONFIG_SUSPEND) || CONFIG_HOTPLUG_CPU */
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/init.h>
16#include <linux/kernel.h>
17#include <linux/kobject.h>
18#include <linux/list.h>
19#include <linux/notifier.h>
20#include <linux/of.h>
21#include <linux/percpu.h>
22#include <linux/slab.h>
23#include <asm/prom.h>
24
25#include "cacheinfo.h"
26
27/* per-cpu object for tracking:
28 * - a "cache" kobject for the top-level directory
29 * - a list of "index" objects representing the cpu's local cache hierarchy
30 */
31struct cache_dir {
32 struct kobject *kobj; /* bare (not embedded) kobject for cache
33 * directory */
34 struct cache_index_dir *index; /* list of index objects */
35};
36
37/* "index" object: each cpu's cache directory has an index
38 * subdirectory corresponding to a cache object associated with the
39 * cpu. This object's lifetime is managed via the embedded kobject.
40 */
41struct cache_index_dir {
42 struct kobject kobj;
43 struct cache_index_dir *next; /* next index in parent directory */
44 struct cache *cache;
45};
46
47/* Template for determining which OF properties to query for a given
48 * cache type */
49struct cache_type_info {
50 const char *name;
51 const char *size_prop;
52
53 /* Allow for both [di]-cache-line-size and
54 * [di]-cache-block-size properties. According to the PowerPC
55 * Processor binding, -line-size should be provided if it
56 * differs from the cache block size (that which is operated
57 * on by cache instructions), so we look for -line-size first.
58 * See cache_get_line_size(). */
59
60 const char *line_size_props[2];
61 const char *nr_sets_prop;
62};
63
64/* These are used to index the cache_type_info array. */
65#define CACHE_TYPE_UNIFIED 0
66#define CACHE_TYPE_INSTRUCTION 1
67#define CACHE_TYPE_DATA 2
68
69static const struct cache_type_info cache_type_info[] = {
70 {
71 /* PowerPC Processor binding says the [di]-cache-*
72 * must be equal on unified caches, so just use
73 * d-cache properties. */
74 .name = "Unified",
75 .size_prop = "d-cache-size",
76 .line_size_props = { "d-cache-line-size",
77 "d-cache-block-size", },
78 .nr_sets_prop = "d-cache-sets",
79 },
80 {
81 .name = "Instruction",
82 .size_prop = "i-cache-size",
83 .line_size_props = { "i-cache-line-size",
84 "i-cache-block-size", },
85 .nr_sets_prop = "i-cache-sets",
86 },
87 {
88 .name = "Data",
89 .size_prop = "d-cache-size",
90 .line_size_props = { "d-cache-line-size",
91 "d-cache-block-size", },
92 .nr_sets_prop = "d-cache-sets",
93 },
94};
95
96/* Cache object: each instance of this corresponds to a distinct cache
97 * in the system. There are separate objects for Harvard caches: one
98 * each for instruction and data, and each refers to the same OF node.
99 * The refcount of the OF node is elevated for the lifetime of the
100 * cache object. A cache object is released when its shared_cpu_map
101 * is cleared (see cache_cpu_clear).
102 *
103 * A cache object is on two lists: an unsorted global list
104 * (cache_list) of cache objects; and a singly-linked list
105 * representing the local cache hierarchy, which is ordered by level
106 * (e.g. L1d -> L1i -> L2 -> L3).
107 */
108struct cache {
109 struct device_node *ofnode; /* OF node for this cache, may be cpu */
110 struct cpumask shared_cpu_map; /* online CPUs using this cache */
111 int type; /* split cache disambiguation */
112 int level; /* level not explicit in device tree */
113 struct list_head list; /* global list of cache objects */
114 struct cache *next_local; /* next cache of >= level */
115};
116
117static DEFINE_PER_CPU(struct cache_dir *, cache_dir_pcpu);
118
119/* traversal/modification of this list occurs only at cpu hotplug time;
120 * access is serialized by cpu hotplug locking
121 */
122static LIST_HEAD(cache_list);
123
124static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *k)
125{
126 return container_of(k, struct cache_index_dir, kobj);
127}
128
129static const char *cache_type_string(const struct cache *cache)
130{
131 return cache_type_info[cache->type].name;
132}
133
134static void __cpuinit cache_init(struct cache *cache, int type, int level, struct device_node *ofnode)
135{
136 cache->type = type;
137 cache->level = level;
138 cache->ofnode = of_node_get(ofnode);
139 INIT_LIST_HEAD(&cache->list);
140 list_add(&cache->list, &cache_list);
141}
142
143static struct cache *__cpuinit new_cache(int type, int level, struct device_node *ofnode)
144{
145 struct cache *cache;
146
147 cache = kzalloc(sizeof(*cache), GFP_KERNEL);
148 if (cache)
149 cache_init(cache, type, level, ofnode);
150
151 return cache;
152}
153
154static void release_cache_debugcheck(struct cache *cache)
155{
156 struct cache *iter;
157
158 list_for_each_entry(iter, &cache_list, list)
159 WARN_ONCE(iter->next_local == cache,
160 "cache for %s(%s) refers to cache for %s(%s)\n",
161 iter->ofnode->full_name,
162 cache_type_string(iter),
163 cache->ofnode->full_name,
164 cache_type_string(cache));
165}
166
167static void release_cache(struct cache *cache)
168{
169 if (!cache)
170 return;
171
172 pr_debug("freeing L%d %s cache for %s\n", cache->level,
173 cache_type_string(cache), cache->ofnode->full_name);
174
175 release_cache_debugcheck(cache);
176 list_del(&cache->list);
177 of_node_put(cache->ofnode);
178 kfree(cache);
179}
180
181static void cache_cpu_set(struct cache *cache, int cpu)
182{
183 struct cache *next = cache;
184
185 while (next) {
186 WARN_ONCE(cpumask_test_cpu(cpu, &next->shared_cpu_map),
187 "CPU %i already accounted in %s(%s)\n",
188 cpu, next->ofnode->full_name,
189 cache_type_string(next));
190 cpumask_set_cpu(cpu, &next->shared_cpu_map);
191 next = next->next_local;
192 }
193}
194
195static int cache_size(const struct cache *cache, unsigned int *ret)
196{
197 const char *propname;
198 const u32 *cache_size;
199
200 propname = cache_type_info[cache->type].size_prop;
201
202 cache_size = of_get_property(cache->ofnode, propname, NULL);
203 if (!cache_size)
204 return -ENODEV;
205
206 *ret = *cache_size;
207 return 0;
208}
209
210static int cache_size_kb(const struct cache *cache, unsigned int *ret)
211{
212 unsigned int size;
213
214 if (cache_size(cache, &size))
215 return -ENODEV;
216
217 *ret = size / 1024;
218 return 0;
219}
220
221/* not cache_line_size() because that's a macro in include/linux/cache.h */
222static int cache_get_line_size(const struct cache *cache, unsigned int *ret)
223{
224 const u32 *line_size;
225 int i, lim;
226
227 lim = ARRAY_SIZE(cache_type_info[cache->type].line_size_props);
228
229 for (i = 0; i < lim; i++) {
230 const char *propname;
231
232 propname = cache_type_info[cache->type].line_size_props[i];
233 line_size = of_get_property(cache->ofnode, propname, NULL);
234 if (line_size)
235 break;
236 }
237
238 if (!line_size)
239 return -ENODEV;
240
241 *ret = *line_size;
242 return 0;
243}
244
245static int cache_nr_sets(const struct cache *cache, unsigned int *ret)
246{
247 const char *propname;
248 const u32 *nr_sets;
249
250 propname = cache_type_info[cache->type].nr_sets_prop;
251
252 nr_sets = of_get_property(cache->ofnode, propname, NULL);
253 if (!nr_sets)
254 return -ENODEV;
255
256 *ret = *nr_sets;
257 return 0;
258}
259
260static int cache_associativity(const struct cache *cache, unsigned int *ret)
261{
262 unsigned int line_size;
263 unsigned int nr_sets;
264 unsigned int size;
265
266 if (cache_nr_sets(cache, &nr_sets))
267 goto err;
268
269 /* If the cache is fully associative, there is no need to
270 * check the other properties.
271 */
272 if (nr_sets == 1) {
273 *ret = 0;
274 return 0;
275 }
276
277 if (cache_get_line_size(cache, &line_size))
278 goto err;
279 if (cache_size(cache, &size))
280 goto err;
281
282 if (!(nr_sets > 0 && size > 0 && line_size > 0))
283 goto err;
284
285 *ret = (size / nr_sets) / line_size;
286 return 0;
287err:
288 return -ENODEV;
289}
290
291/* helper for dealing with split caches */
292static struct cache *cache_find_first_sibling(struct cache *cache)
293{
294 struct cache *iter;
295
296 if (cache->type == CACHE_TYPE_UNIFIED)
297 return cache;
298
299 list_for_each_entry(iter, &cache_list, list)
300 if (iter->ofnode == cache->ofnode && iter->next_local == cache)
301 return iter;
302
303 return cache;
304}
305
306/* return the first cache on a local list matching node */
307static struct cache *cache_lookup_by_node(const struct device_node *node)
308{
309 struct cache *cache = NULL;
310 struct cache *iter;
311
312 list_for_each_entry(iter, &cache_list, list) {
313 if (iter->ofnode != node)
314 continue;
315 cache = cache_find_first_sibling(iter);
316 break;
317 }
318
319 return cache;
320}
321
322static bool cache_node_is_unified(const struct device_node *np)
323{
324 return of_get_property(np, "cache-unified", NULL);
325}
326
327static struct cache *__cpuinit cache_do_one_devnode_unified(struct device_node *node, int level)
328{
329 struct cache *cache;
330
331 pr_debug("creating L%d ucache for %s\n", level, node->full_name);
332
333 cache = new_cache(CACHE_TYPE_UNIFIED, level, node);
334
335 return cache;
336}
337
338static struct cache *__cpuinit cache_do_one_devnode_split(struct device_node *node, int level)
339{
340 struct cache *dcache, *icache;
341
342 pr_debug("creating L%d dcache and icache for %s\n", level,
343 node->full_name);
344
345 dcache = new_cache(CACHE_TYPE_DATA, level, node);
346 icache = new_cache(CACHE_TYPE_INSTRUCTION, level, node);
347
348 if (!dcache || !icache)
349 goto err;
350
351 dcache->next_local = icache;
352
353 return dcache;
354err:
355 release_cache(dcache);
356 release_cache(icache);
357 return NULL;
358}
359
360static struct cache *__cpuinit cache_do_one_devnode(struct device_node *node, int level)
361{
362 struct cache *cache;
363
364 if (cache_node_is_unified(node))
365 cache = cache_do_one_devnode_unified(node, level);
366 else
367 cache = cache_do_one_devnode_split(node, level);
368
369 return cache;
370}
371
372static struct cache *__cpuinit cache_lookup_or_instantiate(struct device_node *node, int level)
373{
374 struct cache *cache;
375
376 cache = cache_lookup_by_node(node);
377
378 WARN_ONCE(cache && cache->level != level,
379 "cache level mismatch on lookup (got %d, expected %d)\n",
380 cache->level, level);
381
382 if (!cache)
383 cache = cache_do_one_devnode(node, level);
384
385 return cache;
386}
387
388static void __cpuinit link_cache_lists(struct cache *smaller, struct cache *bigger)
389{
390 while (smaller->next_local) {
391 if (smaller->next_local == bigger)
392 return; /* already linked */
393 smaller = smaller->next_local;
394 }
395
396 smaller->next_local = bigger;
397}
398
399static void __cpuinit do_subsidiary_caches_debugcheck(struct cache *cache)
400{
401 WARN_ON_ONCE(cache->level != 1);
402 WARN_ON_ONCE(strcmp(cache->ofnode->type, "cpu"));
403}
404
405static void __cpuinit do_subsidiary_caches(struct cache *cache)
406{
407 struct device_node *subcache_node;
408 int level = cache->level;
409
410 do_subsidiary_caches_debugcheck(cache);
411
412 while ((subcache_node = of_find_next_cache_node(cache->ofnode))) {
413 struct cache *subcache;
414
415 level++;
416 subcache = cache_lookup_or_instantiate(subcache_node, level);
417 of_node_put(subcache_node);
418 if (!subcache)
419 break;
420
421 link_cache_lists(cache, subcache);
422 cache = subcache;
423 }
424}
425
426static struct cache *__cpuinit cache_chain_instantiate(unsigned int cpu_id)
427{
428 struct device_node *cpu_node;
429 struct cache *cpu_cache = NULL;
430
431 pr_debug("creating cache object(s) for CPU %i\n", cpu_id);
432
433 cpu_node = of_get_cpu_node(cpu_id, NULL);
434 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
435 if (!cpu_node)
436 goto out;
437
438 cpu_cache = cache_lookup_or_instantiate(cpu_node, 1);
439 if (!cpu_cache)
440 goto out;
441
442 do_subsidiary_caches(cpu_cache);
443
444 cache_cpu_set(cpu_cache, cpu_id);
445out:
446 of_node_put(cpu_node);
447
448 return cpu_cache;
449}
450
451static struct cache_dir *__cpuinit cacheinfo_create_cache_dir(unsigned int cpu_id)
452{
453 struct cache_dir *cache_dir;
454 struct sys_device *sysdev;
455 struct kobject *kobj = NULL;
456
457 sysdev = get_cpu_sysdev(cpu_id);
458 WARN_ONCE(!sysdev, "no sysdev for CPU %i\n", cpu_id);
459 if (!sysdev)
460 goto err;
461
462 kobj = kobject_create_and_add("cache", &sysdev->kobj);
463 if (!kobj)
464 goto err;
465
466 cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL);
467 if (!cache_dir)
468 goto err;
469
470 cache_dir->kobj = kobj;
471
472 WARN_ON_ONCE(per_cpu(cache_dir_pcpu, cpu_id) != NULL);
473
474 per_cpu(cache_dir_pcpu, cpu_id) = cache_dir;
475
476 return cache_dir;
477err:
478 kobject_put(kobj);
479 return NULL;
480}
481
482static void cache_index_release(struct kobject *kobj)
483{
484 struct cache_index_dir *index;
485
486 index = kobj_to_cache_index_dir(kobj);
487
488 pr_debug("freeing index directory for L%d %s cache\n",
489 index->cache->level, cache_type_string(index->cache));
490
491 kfree(index);
492}
493
494static ssize_t cache_index_show(struct kobject *k, struct attribute *attr, char *buf)
495{
496 struct kobj_attribute *kobj_attr;
497
498 kobj_attr = container_of(attr, struct kobj_attribute, attr);
499
500 return kobj_attr->show(k, kobj_attr, buf);
501}
502
503static struct cache *index_kobj_to_cache(struct kobject *k)
504{
505 struct cache_index_dir *index;
506
507 index = kobj_to_cache_index_dir(k);
508
509 return index->cache;
510}
511
512static ssize_t size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
513{
514 unsigned int size_kb;
515 struct cache *cache;
516
517 cache = index_kobj_to_cache(k);
518
519 if (cache_size_kb(cache, &size_kb))
520 return -ENODEV;
521
522 return sprintf(buf, "%uK\n", size_kb);
523}
524
525static struct kobj_attribute cache_size_attr =
526 __ATTR(size, 0444, size_show, NULL);
527
528
529static ssize_t line_size_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
530{
531 unsigned int line_size;
532 struct cache *cache;
533
534 cache = index_kobj_to_cache(k);
535
536 if (cache_get_line_size(cache, &line_size))
537 return -ENODEV;
538
539 return sprintf(buf, "%u\n", line_size);
540}
541
542static struct kobj_attribute cache_line_size_attr =
543 __ATTR(coherency_line_size, 0444, line_size_show, NULL);
544
545static ssize_t nr_sets_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
546{
547 unsigned int nr_sets;
548 struct cache *cache;
549
550 cache = index_kobj_to_cache(k);
551
552 if (cache_nr_sets(cache, &nr_sets))
553 return -ENODEV;
554
555 return sprintf(buf, "%u\n", nr_sets);
556}
557
558static struct kobj_attribute cache_nr_sets_attr =
559 __ATTR(number_of_sets, 0444, nr_sets_show, NULL);
560
561static ssize_t associativity_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
562{
563 unsigned int associativity;
564 struct cache *cache;
565
566 cache = index_kobj_to_cache(k);
567
568 if (cache_associativity(cache, &associativity))
569 return -ENODEV;
570
571 return sprintf(buf, "%u\n", associativity);
572}
573
574static struct kobj_attribute cache_assoc_attr =
575 __ATTR(ways_of_associativity, 0444, associativity_show, NULL);
576
577static ssize_t type_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
578{
579 struct cache *cache;
580
581 cache = index_kobj_to_cache(k);
582
583 return sprintf(buf, "%s\n", cache_type_string(cache));
584}
585
586static struct kobj_attribute cache_type_attr =
587 __ATTR(type, 0444, type_show, NULL);
588
589static ssize_t level_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
590{
591 struct cache_index_dir *index;
592 struct cache *cache;
593
594 index = kobj_to_cache_index_dir(k);
595 cache = index->cache;
596
597 return sprintf(buf, "%d\n", cache->level);
598}
599
600static struct kobj_attribute cache_level_attr =
601 __ATTR(level, 0444, level_show, NULL);
602
603static ssize_t shared_cpu_map_show(struct kobject *k, struct kobj_attribute *attr, char *buf)
604{
605 struct cache_index_dir *index;
606 struct cache *cache;
607 int len;
608 int n = 0;
609
610 index = kobj_to_cache_index_dir(k);
611 cache = index->cache;
612 len = PAGE_SIZE - 2;
613
614 if (len > 1) {
615 n = cpumask_scnprintf(buf, len, &cache->shared_cpu_map);
616 buf[n++] = '\n';
617 buf[n] = '\0';
618 }
619 return n;
620}
621
622static struct kobj_attribute cache_shared_cpu_map_attr =
623 __ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL);
624
625/* Attributes which should always be created -- the kobject/sysfs core
626 * does this automatically via kobj_type->default_attrs. This is the
627 * minimum data required to uniquely identify a cache.
628 */
629static struct attribute *cache_index_default_attrs[] = {
630 &cache_type_attr.attr,
631 &cache_level_attr.attr,
632 &cache_shared_cpu_map_attr.attr,
633 NULL,
634};
635
636/* Attributes which should be created if the cache device node has the
637 * right properties -- see cacheinfo_create_index_opt_attrs
638 */
639static struct kobj_attribute *cache_index_opt_attrs[] = {
640 &cache_size_attr,
641 &cache_line_size_attr,
642 &cache_nr_sets_attr,
643 &cache_assoc_attr,
644};
645
646static const struct sysfs_ops cache_index_ops = {
647 .show = cache_index_show,
648};
649
650static struct kobj_type cache_index_type = {
651 .release = cache_index_release,
652 .sysfs_ops = &cache_index_ops,
653 .default_attrs = cache_index_default_attrs,
654};
655
656static void __cpuinit cacheinfo_create_index_opt_attrs(struct cache_index_dir *dir)
657{
658 const char *cache_name;
659 const char *cache_type;
660 struct cache *cache;
661 char *buf;
662 int i;
663
664 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
665 if (!buf)
666 return;
667
668 cache = dir->cache;
669 cache_name = cache->ofnode->full_name;
670 cache_type = cache_type_string(cache);
671
672 /* We don't want to create an attribute that can't provide a
673 * meaningful value. Check the return value of each optional
674 * attribute's ->show method before registering the
675 * attribute.
676 */
677 for (i = 0; i < ARRAY_SIZE(cache_index_opt_attrs); i++) {
678 struct kobj_attribute *attr;
679 ssize_t rc;
680
681 attr = cache_index_opt_attrs[i];
682
683 rc = attr->show(&dir->kobj, attr, buf);
684 if (rc <= 0) {
685 pr_debug("not creating %s attribute for "
686 "%s(%s) (rc = %zd)\n",
687 attr->attr.name, cache_name,
688 cache_type, rc);
689 continue;
690 }
691 if (sysfs_create_file(&dir->kobj, &attr->attr))
692 pr_debug("could not create %s attribute for %s(%s)\n",
693 attr->attr.name, cache_name, cache_type);
694 }
695
696 kfree(buf);
697}
698
699static void __cpuinit cacheinfo_create_index_dir(struct cache *cache, int index, struct cache_dir *cache_dir)
700{
701 struct cache_index_dir *index_dir;
702 int rc;
703
704 index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL);
705 if (!index_dir)
706 goto err;
707
708 index_dir->cache = cache;
709
710 rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type,
711 cache_dir->kobj, "index%d", index);
712 if (rc)
713 goto err;
714
715 index_dir->next = cache_dir->index;
716 cache_dir->index = index_dir;
717
718 cacheinfo_create_index_opt_attrs(index_dir);
719
720 return;
721err:
722 kfree(index_dir);
723}
724
725static void __cpuinit cacheinfo_sysfs_populate(unsigned int cpu_id, struct cache *cache_list)
726{
727 struct cache_dir *cache_dir;
728 struct cache *cache;
729 int index = 0;
730
731 cache_dir = cacheinfo_create_cache_dir(cpu_id);
732 if (!cache_dir)
733 return;
734
735 cache = cache_list;
736 while (cache) {
737 cacheinfo_create_index_dir(cache, index, cache_dir);
738 index++;
739 cache = cache->next_local;
740 }
741}
742
743void __cpuinit cacheinfo_cpu_online(unsigned int cpu_id)
744{
745 struct cache *cache;
746
747 cache = cache_chain_instantiate(cpu_id);
748 if (!cache)
749 return;
750
751 cacheinfo_sysfs_populate(cpu_id, cache);
752}
753
754#ifdef CONFIG_HOTPLUG_CPU /* functions needed for cpu offline */
755
756static struct cache *cache_lookup_by_cpu(unsigned int cpu_id)
757{
758 struct device_node *cpu_node;
759 struct cache *cache;
760
761 cpu_node = of_get_cpu_node(cpu_id, NULL);
762 WARN_ONCE(!cpu_node, "no OF node found for CPU %i\n", cpu_id);
763 if (!cpu_node)
764 return NULL;
765
766 cache = cache_lookup_by_node(cpu_node);
767 of_node_put(cpu_node);
768
769 return cache;
770}
771
772static void remove_index_dirs(struct cache_dir *cache_dir)
773{
774 struct cache_index_dir *index;
775
776 index = cache_dir->index;
777
778 while (index) {
779 struct cache_index_dir *next;
780
781 next = index->next;
782 kobject_put(&index->kobj);
783 index = next;
784 }
785}
786
787static void remove_cache_dir(struct cache_dir *cache_dir)
788{
789 remove_index_dirs(cache_dir);
790
791 kobject_put(cache_dir->kobj);
792
793 kfree(cache_dir);
794}
795
796static void cache_cpu_clear(struct cache *cache, int cpu)
797{
798 while (cache) {
799 struct cache *next = cache->next_local;
800
801 WARN_ONCE(!cpumask_test_cpu(cpu, &cache->shared_cpu_map),
802 "CPU %i not accounted in %s(%s)\n",
803 cpu, cache->ofnode->full_name,
804 cache_type_string(cache));
805
806 cpumask_clear_cpu(cpu, &cache->shared_cpu_map);
807
808 /* Release the cache object if all the cpus using it
809 * are offline */
810 if (cpumask_empty(&cache->shared_cpu_map))
811 release_cache(cache);
812
813 cache = next;
814 }
815}
816
817void cacheinfo_cpu_offline(unsigned int cpu_id)
818{
819 struct cache_dir *cache_dir;
820 struct cache *cache;
821
822 /* Prevent userspace from seeing inconsistent state - remove
823 * the sysfs hierarchy first */
824 cache_dir = per_cpu(cache_dir_pcpu, cpu_id);
825
826 /* careful, sysfs population may have failed */
827 if (cache_dir)
828 remove_cache_dir(cache_dir);
829
830 per_cpu(cache_dir_pcpu, cpu_id) = NULL;
831
832 /* clear the CPU's bit in its cache chain, possibly freeing
833 * cache objects */
834 cache = cache_lookup_by_cpu(cpu_id);
835 if (cache)
836 cache_cpu_clear(cache, cpu_id);
837}
838#endif /* CONFIG_HOTPLUG_CPU */