1 // SPDX-License-Identifier: GPL-2.0
3 * cacheinfo support - processor cache information via sysfs
5 * Based on arch/x86/kernel/cpu/intel_cacheinfo.c
6 * Author: Sudeep Holla <sudeep.holla@arm.com>
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 #include <linux/acpi.h>
11 #include <linux/bitops.h>
12 #include <linux/cacheinfo.h>
13 #include <linux/compiler.h>
14 #include <linux/cpu.h>
15 #include <linux/device.h>
16 #include <linux/init.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/smp.h>
21 #include <linux/sysfs.h>
23 /* pointer to per cpu cacheinfo */
24 static DEFINE_PER_CPU(struct cpu_cacheinfo, ci_cpu_cacheinfo);
25 #define ci_cacheinfo(cpu) (&per_cpu(ci_cpu_cacheinfo, cpu))
26 #define cache_leaves(cpu) (ci_cacheinfo(cpu)->num_leaves)
27 #define per_cpu_cacheinfo(cpu) (ci_cacheinfo(cpu)->info_list)
28 #define per_cpu_cacheinfo_idx(cpu, idx) \
29 (per_cpu_cacheinfo(cpu) + (idx))
31 /* Set if no cache information is found in DT/ACPI. */
32 static bool use_arch_info;
34 struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu)
36 return ci_cacheinfo(cpu);
39 static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
40 struct cacheinfo *sib_leaf)
43 * For non DT/ACPI systems, assume unique level 1 caches,
44 * system-wide shared caches for all other levels.
46 if (!(IS_ENABLED(CONFIG_OF) || IS_ENABLED(CONFIG_ACPI)) ||
48 return (this_leaf->level != 1) && (sib_leaf->level != 1);
50 if ((sib_leaf->attributes & CACHE_ID) &&
51 (this_leaf->attributes & CACHE_ID))
52 return sib_leaf->id == this_leaf->id;
54 return sib_leaf->fw_token == this_leaf->fw_token;
57 bool last_level_cache_is_valid(unsigned int cpu)
59 struct cacheinfo *llc;
61 if (!cache_leaves(cpu))
64 llc = per_cpu_cacheinfo_idx(cpu, cache_leaves(cpu) - 1);
66 return (llc->attributes & CACHE_ID) || !!llc->fw_token;
70 bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y)
72 struct cacheinfo *llc_x, *llc_y;
74 if (!last_level_cache_is_valid(cpu_x) ||
75 !last_level_cache_is_valid(cpu_y))
78 llc_x = per_cpu_cacheinfo_idx(cpu_x, cache_leaves(cpu_x) - 1);
79 llc_y = per_cpu_cacheinfo_idx(cpu_y, cache_leaves(cpu_y) - 1);
81 return cache_leaves_are_shared(llc_x, llc_y);
86 static bool of_check_cache_nodes(struct device_node *np);
88 /* OF properties to query for a given cache type */
89 struct cache_type_info {
90 const char *size_prop;
91 const char *line_size_props[2];
92 const char *nr_sets_prop;
95 static const struct cache_type_info cache_type_info[] = {
97 .size_prop = "cache-size",
98 .line_size_props = { "cache-line-size",
99 "cache-block-size", },
100 .nr_sets_prop = "cache-sets",
102 .size_prop = "i-cache-size",
103 .line_size_props = { "i-cache-line-size",
104 "i-cache-block-size", },
105 .nr_sets_prop = "i-cache-sets",
107 .size_prop = "d-cache-size",
108 .line_size_props = { "d-cache-line-size",
109 "d-cache-block-size", },
110 .nr_sets_prop = "d-cache-sets",
114 static inline int get_cacheinfo_idx(enum cache_type type)
116 if (type == CACHE_TYPE_UNIFIED)
121 static void cache_size(struct cacheinfo *this_leaf, struct device_node *np)
123 const char *propname;
126 ct_idx = get_cacheinfo_idx(this_leaf->type);
127 propname = cache_type_info[ct_idx].size_prop;
129 of_property_read_u32(np, propname, &this_leaf->size);
132 /* not cache_line_size() because that's a macro in include/linux/cache.h */
133 static void cache_get_line_size(struct cacheinfo *this_leaf,
134 struct device_node *np)
138 ct_idx = get_cacheinfo_idx(this_leaf->type);
139 lim = ARRAY_SIZE(cache_type_info[ct_idx].line_size_props);
141 for (i = 0; i < lim; i++) {
144 const char *propname;
146 propname = cache_type_info[ct_idx].line_size_props[i];
147 ret = of_property_read_u32(np, propname, &line_size);
149 this_leaf->coherency_line_size = line_size;
155 static void cache_nr_sets(struct cacheinfo *this_leaf, struct device_node *np)
157 const char *propname;
160 ct_idx = get_cacheinfo_idx(this_leaf->type);
161 propname = cache_type_info[ct_idx].nr_sets_prop;
163 of_property_read_u32(np, propname, &this_leaf->number_of_sets);
166 static void cache_associativity(struct cacheinfo *this_leaf)
168 unsigned int line_size = this_leaf->coherency_line_size;
169 unsigned int nr_sets = this_leaf->number_of_sets;
170 unsigned int size = this_leaf->size;
173 * If the cache is fully associative, there is no need to
174 * check the other properties.
176 if (!(nr_sets == 1) && (nr_sets > 0 && size > 0 && line_size > 0))
177 this_leaf->ways_of_associativity = (size / nr_sets) / line_size;
180 static bool cache_node_is_unified(struct cacheinfo *this_leaf,
181 struct device_node *np)
183 return of_property_read_bool(np, "cache-unified");
186 static void cache_of_set_props(struct cacheinfo *this_leaf,
187 struct device_node *np)
190 * init_cache_level must setup the cache level correctly
191 * overriding the architecturally specified levels, so
192 * if type is NONE at this stage, it should be unified
194 if (this_leaf->type == CACHE_TYPE_NOCACHE &&
195 cache_node_is_unified(this_leaf, np))
196 this_leaf->type = CACHE_TYPE_UNIFIED;
197 cache_size(this_leaf, np);
198 cache_get_line_size(this_leaf, np);
199 cache_nr_sets(this_leaf, np);
200 cache_associativity(this_leaf);
203 static int cache_setup_of_node(unsigned int cpu)
205 struct device_node *np, *prev;
206 struct cacheinfo *this_leaf;
207 unsigned int index = 0;
209 np = of_cpu_device_node_get(cpu);
211 pr_err("Failed to find cpu%d device node\n", cpu);
215 if (!of_check_cache_nodes(np)) {
222 while (index < cache_leaves(cpu)) {
223 this_leaf = per_cpu_cacheinfo_idx(cpu, index);
224 if (this_leaf->level != 1) {
225 np = of_find_next_cache_node(np);
231 cache_of_set_props(this_leaf, np);
232 this_leaf->fw_token = np;
238 if (index != cache_leaves(cpu)) /* not all OF nodes populated */
244 static bool of_check_cache_nodes(struct device_node *np)
246 struct device_node *next;
248 if (of_property_present(np, "cache-size") ||
249 of_property_present(np, "i-cache-size") ||
250 of_property_present(np, "d-cache-size") ||
251 of_property_present(np, "cache-unified"))
254 next = of_find_next_cache_node(np);
263 static int of_count_cache_leaves(struct device_node *np)
265 unsigned int leaves = 0;
267 if (of_property_read_bool(np, "cache-size"))
269 if (of_property_read_bool(np, "i-cache-size"))
271 if (of_property_read_bool(np, "d-cache-size"))
275 /* The '[i-|d-|]cache-size' property is required, but
276 * if absent, fallback on the 'cache-unified' property.
278 if (of_property_read_bool(np, "cache-unified"))
287 int init_of_cache_level(unsigned int cpu)
289 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
290 struct device_node *np = of_cpu_device_node_get(cpu);
291 struct device_node *prev = NULL;
292 unsigned int levels = 0, leaves, level;
294 if (!of_check_cache_nodes(np)) {
299 leaves = of_count_cache_leaves(np);
304 while ((np = of_find_next_cache_node(np))) {
307 if (!of_device_is_compatible(np, "cache"))
309 if (of_property_read_u32(np, "cache-level", &level))
314 leaves += of_count_cache_leaves(np);
319 this_cpu_ci->num_levels = levels;
320 this_cpu_ci->num_leaves = leaves;
330 static inline int cache_setup_of_node(unsigned int cpu) { return 0; }
331 int init_of_cache_level(unsigned int cpu) { return 0; }
334 int __weak cache_setup_acpi(unsigned int cpu)
339 unsigned int coherency_max_size;
341 static int cache_setup_properties(unsigned int cpu)
345 if (of_have_populated_dt())
346 ret = cache_setup_of_node(cpu);
347 else if (!acpi_disabled)
348 ret = cache_setup_acpi(cpu);
350 // Assume there is no cache information available in DT/ACPI from now.
351 if (ret && use_arch_cache_info())
352 use_arch_info = true;
357 static int cache_shared_cpu_map_setup(unsigned int cpu)
359 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
360 struct cacheinfo *this_leaf, *sib_leaf;
361 unsigned int index, sib_index;
364 if (this_cpu_ci->cpu_map_populated)
368 * skip setting up cache properties if LLC is valid, just need
369 * to update the shared cpu_map if the cache attributes were
370 * populated early before all the cpus are brought online
372 if (!last_level_cache_is_valid(cpu) && !use_arch_info) {
373 ret = cache_setup_properties(cpu);
378 for (index = 0; index < cache_leaves(cpu); index++) {
381 this_leaf = per_cpu_cacheinfo_idx(cpu, index);
383 cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
384 for_each_online_cpu(i) {
385 struct cpu_cacheinfo *sib_cpu_ci = get_cpu_cacheinfo(i);
387 if (i == cpu || !sib_cpu_ci->info_list)
388 continue;/* skip if itself or no cacheinfo */
389 for (sib_index = 0; sib_index < cache_leaves(i); sib_index++) {
390 sib_leaf = per_cpu_cacheinfo_idx(i, sib_index);
393 * Comparing cache IDs only makes sense if the leaves
394 * belong to the same cache level of same type. Skip
395 * the check if level and type do not match.
397 if (sib_leaf->level != this_leaf->level ||
398 sib_leaf->type != this_leaf->type)
401 if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
402 cpumask_set_cpu(cpu, &sib_leaf->shared_cpu_map);
403 cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
408 /* record the maximum cache line size */
409 if (this_leaf->coherency_line_size > coherency_max_size)
410 coherency_max_size = this_leaf->coherency_line_size;
413 /* shared_cpu_map is now populated for the cpu */
414 this_cpu_ci->cpu_map_populated = true;
418 static void cache_shared_cpu_map_remove(unsigned int cpu)
420 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
421 struct cacheinfo *this_leaf, *sib_leaf;
422 unsigned int sibling, index, sib_index;
424 for (index = 0; index < cache_leaves(cpu); index++) {
425 this_leaf = per_cpu_cacheinfo_idx(cpu, index);
426 for_each_cpu(sibling, &this_leaf->shared_cpu_map) {
427 struct cpu_cacheinfo *sib_cpu_ci =
428 get_cpu_cacheinfo(sibling);
430 if (sibling == cpu || !sib_cpu_ci->info_list)
431 continue;/* skip if itself or no cacheinfo */
433 for (sib_index = 0; sib_index < cache_leaves(sibling); sib_index++) {
434 sib_leaf = per_cpu_cacheinfo_idx(sibling, sib_index);
437 * Comparing cache IDs only makes sense if the leaves
438 * belong to the same cache level of same type. Skip
439 * the check if level and type do not match.
441 if (sib_leaf->level != this_leaf->level ||
442 sib_leaf->type != this_leaf->type)
445 if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
446 cpumask_clear_cpu(cpu, &sib_leaf->shared_cpu_map);
447 cpumask_clear_cpu(sibling, &this_leaf->shared_cpu_map);
454 /* cpu is no longer populated in the shared map */
455 this_cpu_ci->cpu_map_populated = false;
458 static void free_cache_attributes(unsigned int cpu)
460 if (!per_cpu_cacheinfo(cpu))
463 cache_shared_cpu_map_remove(cpu);
466 int __weak early_cache_level(unsigned int cpu)
471 int __weak init_cache_level(unsigned int cpu)
476 int __weak populate_cache_leaves(unsigned int cpu)
482 int allocate_cache_info(int cpu)
484 per_cpu_cacheinfo(cpu) = kcalloc(cache_leaves(cpu),
485 sizeof(struct cacheinfo), GFP_ATOMIC);
486 if (!per_cpu_cacheinfo(cpu)) {
487 cache_leaves(cpu) = 0;
494 int fetch_cache_info(unsigned int cpu)
496 struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
497 unsigned int levels = 0, split_levels = 0;
501 ret = init_of_cache_level(cpu);
503 ret = acpi_get_cache_info(cpu, &levels, &split_levels);
505 this_cpu_ci->num_levels = levels;
508 * - there cannot be any split caches (data/instruction)
509 * above a unified cache
510 * - data/instruction caches come by pair
512 this_cpu_ci->num_leaves = levels + split_levels;
516 if (ret || !cache_leaves(cpu)) {
517 ret = early_cache_level(cpu);
521 if (!cache_leaves(cpu))
524 this_cpu_ci->early_ci_levels = true;
527 return allocate_cache_info(cpu);
530 static inline int init_level_allocate_ci(unsigned int cpu)
532 unsigned int early_leaves = cache_leaves(cpu);
534 /* Since early initialization/allocation of the cacheinfo is allowed
535 * via fetch_cache_info() and this also gets called as CPU hotplug
536 * callbacks via cacheinfo_cpu_online, the init/alloc can be skipped
537 * as it will happen only once (the cacheinfo memory is never freed).
538 * Just populate the cacheinfo. However, if the cacheinfo has been
539 * allocated early through the arch-specific early_cache_level() call,
540 * there is a chance the info is wrong (this can happen on arm64). In
541 * that case, call init_cache_level() anyway to give the arch-specific
542 * code a chance to make things right.
544 if (per_cpu_cacheinfo(cpu) && !ci_cacheinfo(cpu)->early_ci_levels)
547 if (init_cache_level(cpu) || !cache_leaves(cpu))
551 * Now that we have properly initialized the cache level info, make
552 * sure we don't try to do that again the next time we are called
553 * (e.g. as CPU hotplug callbacks).
555 ci_cacheinfo(cpu)->early_ci_levels = false;
557 if (cache_leaves(cpu) <= early_leaves)
560 kfree(per_cpu_cacheinfo(cpu));
561 return allocate_cache_info(cpu);
564 int detect_cache_attributes(unsigned int cpu)
568 ret = init_level_allocate_ci(cpu);
573 * If LLC is valid the cache leaves were already populated so just go to
574 * update the cpu map.
576 if (!last_level_cache_is_valid(cpu)) {
578 * populate_cache_leaves() may completely setup the cache leaves and
579 * shared_cpu_map or it may leave it partially setup.
581 ret = populate_cache_leaves(cpu);
587 * For systems using DT for cache hierarchy, fw_token
588 * and shared_cpu_map will be set up here only if they are
589 * not populated already
591 ret = cache_shared_cpu_map_setup(cpu);
593 pr_warn("Unable to detect cache hierarchy for CPU %d\n", cpu);
600 free_cache_attributes(cpu);
604 /* pointer to cpuX/cache device */
605 static DEFINE_PER_CPU(struct device *, ci_cache_dev);
606 #define per_cpu_cache_dev(cpu) (per_cpu(ci_cache_dev, cpu))
608 static cpumask_t cache_dev_map;
610 /* pointer to array of devices for cpuX/cache/indexY */
611 static DEFINE_PER_CPU(struct device **, ci_index_dev);
612 #define per_cpu_index_dev(cpu) (per_cpu(ci_index_dev, cpu))
613 #define per_cache_index_dev(cpu, idx) ((per_cpu_index_dev(cpu))[idx])
615 #define show_one(file_name, object) \
616 static ssize_t file_name##_show(struct device *dev, \
617 struct device_attribute *attr, char *buf) \
619 struct cacheinfo *this_leaf = dev_get_drvdata(dev); \
620 return sysfs_emit(buf, "%u\n", this_leaf->object); \
624 show_one(level, level);
625 show_one(coherency_line_size, coherency_line_size);
626 show_one(number_of_sets, number_of_sets);
627 show_one(physical_line_partition, physical_line_partition);
628 show_one(ways_of_associativity, ways_of_associativity);
630 static ssize_t size_show(struct device *dev,
631 struct device_attribute *attr, char *buf)
633 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
635 return sysfs_emit(buf, "%uK\n", this_leaf->size >> 10);
638 static ssize_t shared_cpu_map_show(struct device *dev,
639 struct device_attribute *attr, char *buf)
641 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
642 const struct cpumask *mask = &this_leaf->shared_cpu_map;
644 return sysfs_emit(buf, "%*pb\n", nr_cpu_ids, mask);
647 static ssize_t shared_cpu_list_show(struct device *dev,
648 struct device_attribute *attr, char *buf)
650 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
651 const struct cpumask *mask = &this_leaf->shared_cpu_map;
653 return sysfs_emit(buf, "%*pbl\n", nr_cpu_ids, mask);
656 static ssize_t type_show(struct device *dev,
657 struct device_attribute *attr, char *buf)
659 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
662 switch (this_leaf->type) {
663 case CACHE_TYPE_DATA:
666 case CACHE_TYPE_INST:
667 output = "Instruction";
669 case CACHE_TYPE_UNIFIED:
676 return sysfs_emit(buf, "%s\n", output);
679 static ssize_t allocation_policy_show(struct device *dev,
680 struct device_attribute *attr, char *buf)
682 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
683 unsigned int ci_attr = this_leaf->attributes;
686 if ((ci_attr & CACHE_READ_ALLOCATE) && (ci_attr & CACHE_WRITE_ALLOCATE))
687 output = "ReadWriteAllocate";
688 else if (ci_attr & CACHE_READ_ALLOCATE)
689 output = "ReadAllocate";
690 else if (ci_attr & CACHE_WRITE_ALLOCATE)
691 output = "WriteAllocate";
695 return sysfs_emit(buf, "%s\n", output);
698 static ssize_t write_policy_show(struct device *dev,
699 struct device_attribute *attr, char *buf)
701 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
702 unsigned int ci_attr = this_leaf->attributes;
705 if (ci_attr & CACHE_WRITE_THROUGH)
706 n = sysfs_emit(buf, "WriteThrough\n");
707 else if (ci_attr & CACHE_WRITE_BACK)
708 n = sysfs_emit(buf, "WriteBack\n");
712 static DEVICE_ATTR_RO(id);
713 static DEVICE_ATTR_RO(level);
714 static DEVICE_ATTR_RO(type);
715 static DEVICE_ATTR_RO(coherency_line_size);
716 static DEVICE_ATTR_RO(ways_of_associativity);
717 static DEVICE_ATTR_RO(number_of_sets);
718 static DEVICE_ATTR_RO(size);
719 static DEVICE_ATTR_RO(allocation_policy);
720 static DEVICE_ATTR_RO(write_policy);
721 static DEVICE_ATTR_RO(shared_cpu_map);
722 static DEVICE_ATTR_RO(shared_cpu_list);
723 static DEVICE_ATTR_RO(physical_line_partition);
725 static struct attribute *cache_default_attrs[] = {
728 &dev_attr_level.attr,
729 &dev_attr_shared_cpu_map.attr,
730 &dev_attr_shared_cpu_list.attr,
731 &dev_attr_coherency_line_size.attr,
732 &dev_attr_ways_of_associativity.attr,
733 &dev_attr_number_of_sets.attr,
735 &dev_attr_allocation_policy.attr,
736 &dev_attr_write_policy.attr,
737 &dev_attr_physical_line_partition.attr,
742 cache_default_attrs_is_visible(struct kobject *kobj,
743 struct attribute *attr, int unused)
745 struct device *dev = kobj_to_dev(kobj);
746 struct cacheinfo *this_leaf = dev_get_drvdata(dev);
747 const struct cpumask *mask = &this_leaf->shared_cpu_map;
748 umode_t mode = attr->mode;
750 if ((attr == &dev_attr_id.attr) && (this_leaf->attributes & CACHE_ID))
752 if ((attr == &dev_attr_type.attr) && this_leaf->type)
754 if ((attr == &dev_attr_level.attr) && this_leaf->level)
756 if ((attr == &dev_attr_shared_cpu_map.attr) && !cpumask_empty(mask))
758 if ((attr == &dev_attr_shared_cpu_list.attr) && !cpumask_empty(mask))
760 if ((attr == &dev_attr_coherency_line_size.attr) &&
761 this_leaf->coherency_line_size)
763 if ((attr == &dev_attr_ways_of_associativity.attr) &&
764 this_leaf->size) /* allow 0 = full associativity */
766 if ((attr == &dev_attr_number_of_sets.attr) &&
767 this_leaf->number_of_sets)
769 if ((attr == &dev_attr_size.attr) && this_leaf->size)
771 if ((attr == &dev_attr_write_policy.attr) &&
772 (this_leaf->attributes & CACHE_WRITE_POLICY_MASK))
774 if ((attr == &dev_attr_allocation_policy.attr) &&
775 (this_leaf->attributes & CACHE_ALLOCATE_POLICY_MASK))
777 if ((attr == &dev_attr_physical_line_partition.attr) &&
778 this_leaf->physical_line_partition)
784 static const struct attribute_group cache_default_group = {
785 .attrs = cache_default_attrs,
786 .is_visible = cache_default_attrs_is_visible,
789 static const struct attribute_group *cache_default_groups[] = {
790 &cache_default_group,
794 static const struct attribute_group *cache_private_groups[] = {
795 &cache_default_group,
796 NULL, /* Place holder for private group */
800 const struct attribute_group *
801 __weak cache_get_priv_group(struct cacheinfo *this_leaf)
806 static const struct attribute_group **
807 cache_get_attribute_groups(struct cacheinfo *this_leaf)
809 const struct attribute_group *priv_group =
810 cache_get_priv_group(this_leaf);
813 return cache_default_groups;
815 if (!cache_private_groups[1])
816 cache_private_groups[1] = priv_group;
818 return cache_private_groups;
821 /* Add/Remove cache interface for CPU device */
822 static void cpu_cache_sysfs_exit(unsigned int cpu)
825 struct device *ci_dev;
827 if (per_cpu_index_dev(cpu)) {
828 for (i = 0; i < cache_leaves(cpu); i++) {
829 ci_dev = per_cache_index_dev(cpu, i);
832 device_unregister(ci_dev);
834 kfree(per_cpu_index_dev(cpu));
835 per_cpu_index_dev(cpu) = NULL;
837 device_unregister(per_cpu_cache_dev(cpu));
838 per_cpu_cache_dev(cpu) = NULL;
841 static int cpu_cache_sysfs_init(unsigned int cpu)
843 struct device *dev = get_cpu_device(cpu);
845 if (per_cpu_cacheinfo(cpu) == NULL)
848 per_cpu_cache_dev(cpu) = cpu_device_create(dev, NULL, NULL, "cache");
849 if (IS_ERR(per_cpu_cache_dev(cpu)))
850 return PTR_ERR(per_cpu_cache_dev(cpu));
852 /* Allocate all required memory */
853 per_cpu_index_dev(cpu) = kcalloc(cache_leaves(cpu),
854 sizeof(struct device *), GFP_KERNEL);
855 if (unlikely(per_cpu_index_dev(cpu) == NULL))
861 cpu_cache_sysfs_exit(cpu);
865 static int cache_add_dev(unsigned int cpu)
869 struct device *ci_dev, *parent;
870 struct cacheinfo *this_leaf;
871 const struct attribute_group **cache_groups;
873 rc = cpu_cache_sysfs_init(cpu);
874 if (unlikely(rc < 0))
877 parent = per_cpu_cache_dev(cpu);
878 for (i = 0; i < cache_leaves(cpu); i++) {
879 this_leaf = per_cpu_cacheinfo_idx(cpu, i);
880 if (this_leaf->disable_sysfs)
882 if (this_leaf->type == CACHE_TYPE_NOCACHE)
884 cache_groups = cache_get_attribute_groups(this_leaf);
885 ci_dev = cpu_device_create(parent, this_leaf, cache_groups,
887 if (IS_ERR(ci_dev)) {
888 rc = PTR_ERR(ci_dev);
891 per_cache_index_dev(cpu, i) = ci_dev;
893 cpumask_set_cpu(cpu, &cache_dev_map);
897 cpu_cache_sysfs_exit(cpu);
901 static int cacheinfo_cpu_online(unsigned int cpu)
903 int rc = detect_cache_attributes(cpu);
907 rc = cache_add_dev(cpu);
909 free_cache_attributes(cpu);
913 static int cacheinfo_cpu_pre_down(unsigned int cpu)
915 if (cpumask_test_and_clear_cpu(cpu, &cache_dev_map))
916 cpu_cache_sysfs_exit(cpu);
918 free_cache_attributes(cpu);
922 static int __init cacheinfo_sysfs_init(void)
924 return cpuhp_setup_state(CPUHP_AP_BASE_CACHEINFO_ONLINE,
925 "base/cacheinfo:online",
926 cacheinfo_cpu_online, cacheinfo_cpu_pre_down);
928 device_initcall(cacheinfo_sysfs_init);