This source file includes following definitions.
- arch_set_freq_scale
- topology_set_cpu_scale
- cpu_capacity_show
- register_cpu_capacity_sysctl
- topology_update_cpu_topology
- update_topology_flags_workfn
- free_raw_capacity
- topology_normalize_cpu_scale
- topology_parse_cpu_capacity
- init_cpu_capacity_callback
- register_cpufreq_notifier
- parsing_done_workfn
- get_cpu_for_node
- parse_core
- parse_cluster
- parse_dt_topology
- cpu_coregroup_mask
- update_siblings_masks
- clear_cpu_topology
- reset_cpu_topology
- remove_cpu_topology
- parse_acpi_topology
- init_cpu_topology
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9 #include <linux/acpi.h>
10 #include <linux/cpu.h>
11 #include <linux/cpufreq.h>
12 #include <linux/device.h>
13 #include <linux/of.h>
14 #include <linux/slab.h>
15 #include <linux/string.h>
16 #include <linux/sched/topology.h>
17 #include <linux/cpuset.h>
18 #include <linux/cpumask.h>
19 #include <linux/init.h>
20 #include <linux/percpu.h>
21 #include <linux/sched.h>
22 #include <linux/smp.h>
23
24 DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE;
25
26 void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq,
27 unsigned long max_freq)
28 {
29 unsigned long scale;
30 int i;
31
32 scale = (cur_freq << SCHED_CAPACITY_SHIFT) / max_freq;
33
34 for_each_cpu(i, cpus)
35 per_cpu(freq_scale, i) = scale;
36 }
37
38 DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
39
40 void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
41 {
42 per_cpu(cpu_scale, cpu) = capacity;
43 }
44
45 static ssize_t cpu_capacity_show(struct device *dev,
46 struct device_attribute *attr,
47 char *buf)
48 {
49 struct cpu *cpu = container_of(dev, struct cpu, dev);
50
51 return sprintf(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
52 }
53
54 static void update_topology_flags_workfn(struct work_struct *work);
55 static DECLARE_WORK(update_topology_flags_work, update_topology_flags_workfn);
56
57 static DEVICE_ATTR_RO(cpu_capacity);
58
59 static int register_cpu_capacity_sysctl(void)
60 {
61 int i;
62 struct device *cpu;
63
64 for_each_possible_cpu(i) {
65 cpu = get_cpu_device(i);
66 if (!cpu) {
67 pr_err("%s: too early to get CPU%d device!\n",
68 __func__, i);
69 continue;
70 }
71 device_create_file(cpu, &dev_attr_cpu_capacity);
72 }
73
74 return 0;
75 }
76 subsys_initcall(register_cpu_capacity_sysctl);
77
78 static int update_topology;
79
80 int topology_update_cpu_topology(void)
81 {
82 return update_topology;
83 }
84
85
86
87
88
89 static void update_topology_flags_workfn(struct work_struct *work)
90 {
91 update_topology = 1;
92 rebuild_sched_domains();
93 pr_debug("sched_domain hierarchy rebuilt, flags updated\n");
94 update_topology = 0;
95 }
96
97 static u32 capacity_scale;
98 static u32 *raw_capacity;
99
100 static int free_raw_capacity(void)
101 {
102 kfree(raw_capacity);
103 raw_capacity = NULL;
104
105 return 0;
106 }
107
108 void topology_normalize_cpu_scale(void)
109 {
110 u64 capacity;
111 int cpu;
112
113 if (!raw_capacity)
114 return;
115
116 pr_debug("cpu_capacity: capacity_scale=%u\n", capacity_scale);
117 for_each_possible_cpu(cpu) {
118 pr_debug("cpu_capacity: cpu=%d raw_capacity=%u\n",
119 cpu, raw_capacity[cpu]);
120 capacity = (raw_capacity[cpu] << SCHED_CAPACITY_SHIFT)
121 / capacity_scale;
122 topology_set_cpu_scale(cpu, capacity);
123 pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
124 cpu, topology_get_cpu_scale(cpu));
125 }
126 }
127
128 bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
129 {
130 static bool cap_parsing_failed;
131 int ret;
132 u32 cpu_capacity;
133
134 if (cap_parsing_failed)
135 return false;
136
137 ret = of_property_read_u32(cpu_node, "capacity-dmips-mhz",
138 &cpu_capacity);
139 if (!ret) {
140 if (!raw_capacity) {
141 raw_capacity = kcalloc(num_possible_cpus(),
142 sizeof(*raw_capacity),
143 GFP_KERNEL);
144 if (!raw_capacity) {
145 cap_parsing_failed = true;
146 return false;
147 }
148 }
149 capacity_scale = max(cpu_capacity, capacity_scale);
150 raw_capacity[cpu] = cpu_capacity;
151 pr_debug("cpu_capacity: %pOF cpu_capacity=%u (raw)\n",
152 cpu_node, raw_capacity[cpu]);
153 } else {
154 if (raw_capacity) {
155 pr_err("cpu_capacity: missing %pOF raw capacity\n",
156 cpu_node);
157 pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
158 }
159 cap_parsing_failed = true;
160 free_raw_capacity();
161 }
162
163 return !ret;
164 }
165
166 #ifdef CONFIG_CPU_FREQ
167 static cpumask_var_t cpus_to_visit;
168 static void parsing_done_workfn(struct work_struct *work);
169 static DECLARE_WORK(parsing_done_work, parsing_done_workfn);
170
171 static int
172 init_cpu_capacity_callback(struct notifier_block *nb,
173 unsigned long val,
174 void *data)
175 {
176 struct cpufreq_policy *policy = data;
177 int cpu;
178
179 if (!raw_capacity)
180 return 0;
181
182 if (val != CPUFREQ_CREATE_POLICY)
183 return 0;
184
185 pr_debug("cpu_capacity: init cpu capacity for CPUs [%*pbl] (to_visit=%*pbl)\n",
186 cpumask_pr_args(policy->related_cpus),
187 cpumask_pr_args(cpus_to_visit));
188
189 cpumask_andnot(cpus_to_visit, cpus_to_visit, policy->related_cpus);
190
191 for_each_cpu(cpu, policy->related_cpus) {
192 raw_capacity[cpu] = topology_get_cpu_scale(cpu) *
193 policy->cpuinfo.max_freq / 1000UL;
194 capacity_scale = max(raw_capacity[cpu], capacity_scale);
195 }
196
197 if (cpumask_empty(cpus_to_visit)) {
198 topology_normalize_cpu_scale();
199 schedule_work(&update_topology_flags_work);
200 free_raw_capacity();
201 pr_debug("cpu_capacity: parsing done\n");
202 schedule_work(&parsing_done_work);
203 }
204
205 return 0;
206 }
207
208 static struct notifier_block init_cpu_capacity_notifier = {
209 .notifier_call = init_cpu_capacity_callback,
210 };
211
212 static int __init register_cpufreq_notifier(void)
213 {
214 int ret;
215
216
217
218
219
220
221 if (!acpi_disabled || !raw_capacity)
222 return -EINVAL;
223
224 if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL))
225 return -ENOMEM;
226
227 cpumask_copy(cpus_to_visit, cpu_possible_mask);
228
229 ret = cpufreq_register_notifier(&init_cpu_capacity_notifier,
230 CPUFREQ_POLICY_NOTIFIER);
231
232 if (ret)
233 free_cpumask_var(cpus_to_visit);
234
235 return ret;
236 }
237 core_initcall(register_cpufreq_notifier);
238
239 static void parsing_done_workfn(struct work_struct *work)
240 {
241 cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
242 CPUFREQ_POLICY_NOTIFIER);
243 free_cpumask_var(cpus_to_visit);
244 }
245
246 #else
247 core_initcall(free_raw_capacity);
248 #endif
249
250 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
251 static int __init get_cpu_for_node(struct device_node *node)
252 {
253 struct device_node *cpu_node;
254 int cpu;
255
256 cpu_node = of_parse_phandle(node, "cpu", 0);
257 if (!cpu_node)
258 return -1;
259
260 cpu = of_cpu_node_to_id(cpu_node);
261 if (cpu >= 0)
262 topology_parse_cpu_capacity(cpu_node, cpu);
263 else
264 pr_crit("Unable to find CPU node for %pOF\n", cpu_node);
265
266 of_node_put(cpu_node);
267 return cpu;
268 }
269
270 static int __init parse_core(struct device_node *core, int package_id,
271 int core_id)
272 {
273 char name[10];
274 bool leaf = true;
275 int i = 0;
276 int cpu;
277 struct device_node *t;
278
279 do {
280 snprintf(name, sizeof(name), "thread%d", i);
281 t = of_get_child_by_name(core, name);
282 if (t) {
283 leaf = false;
284 cpu = get_cpu_for_node(t);
285 if (cpu >= 0) {
286 cpu_topology[cpu].package_id = package_id;
287 cpu_topology[cpu].core_id = core_id;
288 cpu_topology[cpu].thread_id = i;
289 } else {
290 pr_err("%pOF: Can't get CPU for thread\n",
291 t);
292 of_node_put(t);
293 return -EINVAL;
294 }
295 of_node_put(t);
296 }
297 i++;
298 } while (t);
299
300 cpu = get_cpu_for_node(core);
301 if (cpu >= 0) {
302 if (!leaf) {
303 pr_err("%pOF: Core has both threads and CPU\n",
304 core);
305 return -EINVAL;
306 }
307
308 cpu_topology[cpu].package_id = package_id;
309 cpu_topology[cpu].core_id = core_id;
310 } else if (leaf) {
311 pr_err("%pOF: Can't get CPU for leaf core\n", core);
312 return -EINVAL;
313 }
314
315 return 0;
316 }
317
318 static int __init parse_cluster(struct device_node *cluster, int depth)
319 {
320 char name[10];
321 bool leaf = true;
322 bool has_cores = false;
323 struct device_node *c;
324 static int package_id __initdata;
325 int core_id = 0;
326 int i, ret;
327
328
329
330
331
332
333 i = 0;
334 do {
335 snprintf(name, sizeof(name), "cluster%d", i);
336 c = of_get_child_by_name(cluster, name);
337 if (c) {
338 leaf = false;
339 ret = parse_cluster(c, depth + 1);
340 of_node_put(c);
341 if (ret != 0)
342 return ret;
343 }
344 i++;
345 } while (c);
346
347
348 i = 0;
349 do {
350 snprintf(name, sizeof(name), "core%d", i);
351 c = of_get_child_by_name(cluster, name);
352 if (c) {
353 has_cores = true;
354
355 if (depth == 0) {
356 pr_err("%pOF: cpu-map children should be clusters\n",
357 c);
358 of_node_put(c);
359 return -EINVAL;
360 }
361
362 if (leaf) {
363 ret = parse_core(c, package_id, core_id++);
364 } else {
365 pr_err("%pOF: Non-leaf cluster with core %s\n",
366 cluster, name);
367 ret = -EINVAL;
368 }
369
370 of_node_put(c);
371 if (ret != 0)
372 return ret;
373 }
374 i++;
375 } while (c);
376
377 if (leaf && !has_cores)
378 pr_warn("%pOF: empty cluster\n", cluster);
379
380 if (leaf)
381 package_id++;
382
383 return 0;
384 }
385
386 static int __init parse_dt_topology(void)
387 {
388 struct device_node *cn, *map;
389 int ret = 0;
390 int cpu;
391
392 cn = of_find_node_by_path("/cpus");
393 if (!cn) {
394 pr_err("No CPU information found in DT\n");
395 return 0;
396 }
397
398
399
400
401
402 map = of_get_child_by_name(cn, "cpu-map");
403 if (!map)
404 goto out;
405
406 ret = parse_cluster(map, 0);
407 if (ret != 0)
408 goto out_map;
409
410 topology_normalize_cpu_scale();
411
412
413
414
415
416 for_each_possible_cpu(cpu)
417 if (cpu_topology[cpu].package_id == -1)
418 ret = -EINVAL;
419
420 out_map:
421 of_node_put(map);
422 out:
423 of_node_put(cn);
424 return ret;
425 }
426 #endif
427
428
429
430
431 struct cpu_topology cpu_topology[NR_CPUS];
432 EXPORT_SYMBOL_GPL(cpu_topology);
433
434 const struct cpumask *cpu_coregroup_mask(int cpu)
435 {
436 const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));
437
438
439 if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
440
441 core_mask = &cpu_topology[cpu].core_sibling;
442 }
443 if (cpu_topology[cpu].llc_id != -1) {
444 if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
445 core_mask = &cpu_topology[cpu].llc_sibling;
446 }
447
448 return core_mask;
449 }
450
451 void update_siblings_masks(unsigned int cpuid)
452 {
453 struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
454 int cpu;
455
456
457 for_each_online_cpu(cpu) {
458 cpu_topo = &cpu_topology[cpu];
459
460 if (cpuid_topo->llc_id == cpu_topo->llc_id) {
461 cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
462 cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
463 }
464
465 if (cpuid_topo->package_id != cpu_topo->package_id)
466 continue;
467
468 cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
469 cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
470
471 if (cpuid_topo->core_id != cpu_topo->core_id)
472 continue;
473
474 cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
475 cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
476 }
477 }
478
479 static void clear_cpu_topology(int cpu)
480 {
481 struct cpu_topology *cpu_topo = &cpu_topology[cpu];
482
483 cpumask_clear(&cpu_topo->llc_sibling);
484 cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);
485
486 cpumask_clear(&cpu_topo->core_sibling);
487 cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
488 cpumask_clear(&cpu_topo->thread_sibling);
489 cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
490 }
491
492 void __init reset_cpu_topology(void)
493 {
494 unsigned int cpu;
495
496 for_each_possible_cpu(cpu) {
497 struct cpu_topology *cpu_topo = &cpu_topology[cpu];
498
499 cpu_topo->thread_id = -1;
500 cpu_topo->core_id = -1;
501 cpu_topo->package_id = -1;
502 cpu_topo->llc_id = -1;
503
504 clear_cpu_topology(cpu);
505 }
506 }
507
508 void remove_cpu_topology(unsigned int cpu)
509 {
510 int sibling;
511
512 for_each_cpu(sibling, topology_core_cpumask(cpu))
513 cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
514 for_each_cpu(sibling, topology_sibling_cpumask(cpu))
515 cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
516 for_each_cpu(sibling, topology_llc_cpumask(cpu))
517 cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));
518
519 clear_cpu_topology(cpu);
520 }
521
522 __weak int __init parse_acpi_topology(void)
523 {
524 return 0;
525 }
526
527 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
528 void __init init_cpu_topology(void)
529 {
530 reset_cpu_topology();
531
532
533
534
535
536 if (parse_acpi_topology())
537 reset_cpu_topology();
538 else if (of_have_populated_dt() && parse_dt_topology())
539 reset_cpu_topology();
540 }
541 #endif