xref: /openbmc/linux/drivers/base/arch_topology.c (revision ffcdf473)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Arch specific cpu topology information
4  *
5  * Copyright (C) 2016, ARM Ltd.
6  * Written by: Juri Lelli, ARM Ltd.
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/cacheinfo.h>
11 #include <linux/cpu.h>
12 #include <linux/cpufreq.h>
13 #include <linux/device.h>
14 #include <linux/of.h>
15 #include <linux/slab.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/rcupdate.h>
21 #include <linux/sched.h>
22 
23 #define CREATE_TRACE_POINTS
24 #include <trace/events/thermal_pressure.h>
25 
26 static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data);
27 static struct cpumask scale_freq_counters_mask;
28 static bool scale_freq_invariant;
29 static DEFINE_PER_CPU(u32, freq_factor) = 1;
30 
31 static bool supports_scale_freq_counters(const struct cpumask *cpus)
32 {
33 	return cpumask_subset(cpus, &scale_freq_counters_mask);
34 }
35 
36 bool topology_scale_freq_invariant(void)
37 {
38 	return cpufreq_supports_freq_invariance() ||
39 	       supports_scale_freq_counters(cpu_online_mask);
40 }
41 
42 static void update_scale_freq_invariant(bool status)
43 {
44 	if (scale_freq_invariant == status)
45 		return;
46 
47 	/*
48 	 * Task scheduler behavior depends on frequency invariance support,
49 	 * either cpufreq or counter driven. If the support status changes as
50 	 * a result of counter initialisation and use, retrigger the build of
51 	 * scheduling domains to ensure the information is propagated properly.
52 	 */
53 	if (topology_scale_freq_invariant() == status) {
54 		scale_freq_invariant = status;
55 		rebuild_sched_domains_energy();
56 	}
57 }
58 
59 void topology_set_scale_freq_source(struct scale_freq_data *data,
60 				    const struct cpumask *cpus)
61 {
62 	struct scale_freq_data *sfd;
63 	int cpu;
64 
65 	/*
66 	 * Avoid calling rebuild_sched_domains() unnecessarily if FIE is
67 	 * supported by cpufreq.
68 	 */
69 	if (cpumask_empty(&scale_freq_counters_mask))
70 		scale_freq_invariant = topology_scale_freq_invariant();
71 
72 	rcu_read_lock();
73 
74 	for_each_cpu(cpu, cpus) {
75 		sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu));
76 
77 		/* Use ARCH provided counters whenever possible */
78 		if (!sfd || sfd->source != SCALE_FREQ_SOURCE_ARCH) {
79 			rcu_assign_pointer(per_cpu(sft_data, cpu), data);
80 			cpumask_set_cpu(cpu, &scale_freq_counters_mask);
81 		}
82 	}
83 
84 	rcu_read_unlock();
85 
86 	update_scale_freq_invariant(true);
87 }
88 EXPORT_SYMBOL_GPL(topology_set_scale_freq_source);
89 
90 void topology_clear_scale_freq_source(enum scale_freq_source source,
91 				      const struct cpumask *cpus)
92 {
93 	struct scale_freq_data *sfd;
94 	int cpu;
95 
96 	rcu_read_lock();
97 
98 	for_each_cpu(cpu, cpus) {
99 		sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu));
100 
101 		if (sfd && sfd->source == source) {
102 			rcu_assign_pointer(per_cpu(sft_data, cpu), NULL);
103 			cpumask_clear_cpu(cpu, &scale_freq_counters_mask);
104 		}
105 	}
106 
107 	rcu_read_unlock();
108 
109 	/*
110 	 * Make sure all references to previous sft_data are dropped to avoid
111 	 * use-after-free races.
112 	 */
113 	synchronize_rcu();
114 
115 	update_scale_freq_invariant(false);
116 }
117 EXPORT_SYMBOL_GPL(topology_clear_scale_freq_source);
118 
119 void topology_scale_freq_tick(void)
120 {
121 	struct scale_freq_data *sfd = rcu_dereference_sched(*this_cpu_ptr(&sft_data));
122 
123 	if (sfd)
124 		sfd->set_freq_scale();
125 }
126 
127 DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE;
128 EXPORT_PER_CPU_SYMBOL_GPL(arch_freq_scale);
129 
130 void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq,
131 			     unsigned long max_freq)
132 {
133 	unsigned long scale;
134 	int i;
135 
136 	if (WARN_ON_ONCE(!cur_freq || !max_freq))
137 		return;
138 
139 	/*
140 	 * If the use of counters for FIE is enabled, just return as we don't
141 	 * want to update the scale factor with information from CPUFREQ.
142 	 * Instead the scale factor will be updated from arch_scale_freq_tick.
143 	 */
144 	if (supports_scale_freq_counters(cpus))
145 		return;
146 
147 	scale = (cur_freq << SCHED_CAPACITY_SHIFT) / max_freq;
148 
149 	for_each_cpu(i, cpus)
150 		per_cpu(arch_freq_scale, i) = scale;
151 }
152 
153 DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
154 EXPORT_PER_CPU_SYMBOL_GPL(cpu_scale);
155 
156 void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
157 {
158 	per_cpu(cpu_scale, cpu) = capacity;
159 }
160 
161 DEFINE_PER_CPU(unsigned long, thermal_pressure);
162 
163 /**
164  * topology_update_thermal_pressure() - Update thermal pressure for CPUs
165  * @cpus        : The related CPUs for which capacity has been reduced
166  * @capped_freq : The maximum allowed frequency that CPUs can run at
167  *
168  * Update the value of thermal pressure for all @cpus in the mask. The
169  * cpumask should include all (online+offline) affected CPUs, to avoid
170  * operating on stale data when hot-plug is used for some CPUs. The
171  * @capped_freq reflects the currently allowed max CPUs frequency due to
172  * thermal capping. It might be also a boost frequency value, which is bigger
173  * than the internal 'freq_factor' max frequency. In such case the pressure
174  * value should simply be removed, since this is an indication that there is
175  * no thermal throttling. The @capped_freq must be provided in kHz.
176  */
177 void topology_update_thermal_pressure(const struct cpumask *cpus,
178 				      unsigned long capped_freq)
179 {
180 	unsigned long max_capacity, capacity, th_pressure;
181 	u32 max_freq;
182 	int cpu;
183 
184 	cpu = cpumask_first(cpus);
185 	max_capacity = arch_scale_cpu_capacity(cpu);
186 	max_freq = per_cpu(freq_factor, cpu);
187 
188 	/* Convert to MHz scale which is used in 'freq_factor' */
189 	capped_freq /= 1000;
190 
191 	/*
192 	 * Handle properly the boost frequencies, which should simply clean
193 	 * the thermal pressure value.
194 	 */
195 	if (max_freq <= capped_freq)
196 		capacity = max_capacity;
197 	else
198 		capacity = mult_frac(max_capacity, capped_freq, max_freq);
199 
200 	th_pressure = max_capacity - capacity;
201 
202 	trace_thermal_pressure_update(cpu, th_pressure);
203 
204 	for_each_cpu(cpu, cpus)
205 		WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);
206 }
207 EXPORT_SYMBOL_GPL(topology_update_thermal_pressure);
208 
209 static ssize_t cpu_capacity_show(struct device *dev,
210 				 struct device_attribute *attr,
211 				 char *buf)
212 {
213 	struct cpu *cpu = container_of(dev, struct cpu, dev);
214 
215 	return sysfs_emit(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
216 }
217 
218 static void update_topology_flags_workfn(struct work_struct *work);
219 static DECLARE_WORK(update_topology_flags_work, update_topology_flags_workfn);
220 
221 static DEVICE_ATTR_RO(cpu_capacity);
222 
223 static int register_cpu_capacity_sysctl(void)
224 {
225 	int i;
226 	struct device *cpu;
227 
228 	for_each_possible_cpu(i) {
229 		cpu = get_cpu_device(i);
230 		if (!cpu) {
231 			pr_err("%s: too early to get CPU%d device!\n",
232 			       __func__, i);
233 			continue;
234 		}
235 		device_create_file(cpu, &dev_attr_cpu_capacity);
236 	}
237 
238 	return 0;
239 }
240 subsys_initcall(register_cpu_capacity_sysctl);
241 
242 static int update_topology;
243 
244 int topology_update_cpu_topology(void)
245 {
246 	return update_topology;
247 }
248 
249 /*
250  * Updating the sched_domains can't be done directly from cpufreq callbacks
251  * due to locking, so queue the work for later.
252  */
253 static void update_topology_flags_workfn(struct work_struct *work)
254 {
255 	update_topology = 1;
256 	rebuild_sched_domains();
257 	pr_debug("sched_domain hierarchy rebuilt, flags updated\n");
258 	update_topology = 0;
259 }
260 
261 static u32 *raw_capacity;
262 
263 static int free_raw_capacity(void)
264 {
265 	kfree(raw_capacity);
266 	raw_capacity = NULL;
267 
268 	return 0;
269 }
270 
271 void topology_normalize_cpu_scale(void)
272 {
273 	u64 capacity;
274 	u64 capacity_scale;
275 	int cpu;
276 
277 	if (!raw_capacity)
278 		return;
279 
280 	capacity_scale = 1;
281 	for_each_possible_cpu(cpu) {
282 		capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
283 		capacity_scale = max(capacity, capacity_scale);
284 	}
285 
286 	pr_debug("cpu_capacity: capacity_scale=%llu\n", capacity_scale);
287 	for_each_possible_cpu(cpu) {
288 		capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
289 		capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
290 			capacity_scale);
291 		topology_set_cpu_scale(cpu, capacity);
292 		pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
293 			cpu, topology_get_cpu_scale(cpu));
294 	}
295 }
296 
297 bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
298 {
299 	struct clk *cpu_clk;
300 	static bool cap_parsing_failed;
301 	int ret;
302 	u32 cpu_capacity;
303 
304 	if (cap_parsing_failed)
305 		return false;
306 
307 	ret = of_property_read_u32(cpu_node, "capacity-dmips-mhz",
308 				   &cpu_capacity);
309 	if (!ret) {
310 		if (!raw_capacity) {
311 			raw_capacity = kcalloc(num_possible_cpus(),
312 					       sizeof(*raw_capacity),
313 					       GFP_KERNEL);
314 			if (!raw_capacity) {
315 				cap_parsing_failed = true;
316 				return false;
317 			}
318 		}
319 		raw_capacity[cpu] = cpu_capacity;
320 		pr_debug("cpu_capacity: %pOF cpu_capacity=%u (raw)\n",
321 			cpu_node, raw_capacity[cpu]);
322 
323 		/*
324 		 * Update freq_factor for calculating early boot cpu capacities.
325 		 * For non-clk CPU DVFS mechanism, there's no way to get the
326 		 * frequency value now, assuming they are running at the same
327 		 * frequency (by keeping the initial freq_factor value).
328 		 */
329 		cpu_clk = of_clk_get(cpu_node, 0);
330 		if (!PTR_ERR_OR_ZERO(cpu_clk)) {
331 			per_cpu(freq_factor, cpu) =
332 				clk_get_rate(cpu_clk) / 1000;
333 			clk_put(cpu_clk);
334 		}
335 	} else {
336 		if (raw_capacity) {
337 			pr_err("cpu_capacity: missing %pOF raw capacity\n",
338 				cpu_node);
339 			pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
340 		}
341 		cap_parsing_failed = true;
342 		free_raw_capacity();
343 	}
344 
345 	return !ret;
346 }
347 
348 #ifdef CONFIG_ACPI_CPPC_LIB
349 #include <acpi/cppc_acpi.h>
350 
351 void topology_init_cpu_capacity_cppc(void)
352 {
353 	struct cppc_perf_caps perf_caps;
354 	int cpu;
355 
356 	if (likely(!acpi_cpc_valid()))
357 		return;
358 
359 	raw_capacity = kcalloc(num_possible_cpus(), sizeof(*raw_capacity),
360 			       GFP_KERNEL);
361 	if (!raw_capacity)
362 		return;
363 
364 	for_each_possible_cpu(cpu) {
365 		if (!cppc_get_perf_caps(cpu, &perf_caps) &&
366 		    (perf_caps.highest_perf >= perf_caps.nominal_perf) &&
367 		    (perf_caps.highest_perf >= perf_caps.lowest_perf)) {
368 			raw_capacity[cpu] = perf_caps.highest_perf;
369 			pr_debug("cpu_capacity: CPU%d cpu_capacity=%u (raw).\n",
370 				 cpu, raw_capacity[cpu]);
371 			continue;
372 		}
373 
374 		pr_err("cpu_capacity: CPU%d missing/invalid highest performance.\n", cpu);
375 		pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
376 		goto exit;
377 	}
378 
379 	topology_normalize_cpu_scale();
380 	schedule_work(&update_topology_flags_work);
381 	pr_debug("cpu_capacity: cpu_capacity initialization done\n");
382 
383 exit:
384 	free_raw_capacity();
385 }
386 #endif
387 
388 #ifdef CONFIG_CPU_FREQ
389 static cpumask_var_t cpus_to_visit;
390 static void parsing_done_workfn(struct work_struct *work);
391 static DECLARE_WORK(parsing_done_work, parsing_done_workfn);
392 
393 static int
394 init_cpu_capacity_callback(struct notifier_block *nb,
395 			   unsigned long val,
396 			   void *data)
397 {
398 	struct cpufreq_policy *policy = data;
399 	int cpu;
400 
401 	if (!raw_capacity)
402 		return 0;
403 
404 	if (val != CPUFREQ_CREATE_POLICY)
405 		return 0;
406 
407 	pr_debug("cpu_capacity: init cpu capacity for CPUs [%*pbl] (to_visit=%*pbl)\n",
408 		 cpumask_pr_args(policy->related_cpus),
409 		 cpumask_pr_args(cpus_to_visit));
410 
411 	cpumask_andnot(cpus_to_visit, cpus_to_visit, policy->related_cpus);
412 
413 	for_each_cpu(cpu, policy->related_cpus)
414 		per_cpu(freq_factor, cpu) = policy->cpuinfo.max_freq / 1000;
415 
416 	if (cpumask_empty(cpus_to_visit)) {
417 		topology_normalize_cpu_scale();
418 		schedule_work(&update_topology_flags_work);
419 		free_raw_capacity();
420 		pr_debug("cpu_capacity: parsing done\n");
421 		schedule_work(&parsing_done_work);
422 	}
423 
424 	return 0;
425 }
426 
427 static struct notifier_block init_cpu_capacity_notifier = {
428 	.notifier_call = init_cpu_capacity_callback,
429 };
430 
431 static int __init register_cpufreq_notifier(void)
432 {
433 	int ret;
434 
435 	/*
436 	 * On ACPI-based systems skip registering cpufreq notifier as cpufreq
437 	 * information is not needed for cpu capacity initialization.
438 	 */
439 	if (!acpi_disabled || !raw_capacity)
440 		return -EINVAL;
441 
442 	if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL))
443 		return -ENOMEM;
444 
445 	cpumask_copy(cpus_to_visit, cpu_possible_mask);
446 
447 	ret = cpufreq_register_notifier(&init_cpu_capacity_notifier,
448 					CPUFREQ_POLICY_NOTIFIER);
449 
450 	if (ret)
451 		free_cpumask_var(cpus_to_visit);
452 
453 	return ret;
454 }
455 core_initcall(register_cpufreq_notifier);
456 
457 static void parsing_done_workfn(struct work_struct *work)
458 {
459 	cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
460 					 CPUFREQ_POLICY_NOTIFIER);
461 	free_cpumask_var(cpus_to_visit);
462 }
463 
464 #else
465 core_initcall(free_raw_capacity);
466 #endif
467 
468 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
469 /*
470  * This function returns the logic cpu number of the node.
471  * There are basically three kinds of return values:
472  * (1) logic cpu number which is > 0.
473  * (2) -ENODEV when the device tree(DT) node is valid and found in the DT but
474  * there is no possible logical CPU in the kernel to match. This happens
475  * when CONFIG_NR_CPUS is configure to be smaller than the number of
476  * CPU nodes in DT. We need to just ignore this case.
477  * (3) -1 if the node does not exist in the device tree
478  */
479 static int __init get_cpu_for_node(struct device_node *node)
480 {
481 	struct device_node *cpu_node;
482 	int cpu;
483 
484 	cpu_node = of_parse_phandle(node, "cpu", 0);
485 	if (!cpu_node)
486 		return -1;
487 
488 	cpu = of_cpu_node_to_id(cpu_node);
489 	if (cpu >= 0)
490 		topology_parse_cpu_capacity(cpu_node, cpu);
491 	else
492 		pr_info("CPU node for %pOF exist but the possible cpu range is :%*pbl\n",
493 			cpu_node, cpumask_pr_args(cpu_possible_mask));
494 
495 	of_node_put(cpu_node);
496 	return cpu;
497 }
498 
499 static int __init parse_core(struct device_node *core, int package_id,
500 			     int cluster_id, int core_id)
501 {
502 	char name[20];
503 	bool leaf = true;
504 	int i = 0;
505 	int cpu;
506 	struct device_node *t;
507 
508 	do {
509 		snprintf(name, sizeof(name), "thread%d", i);
510 		t = of_get_child_by_name(core, name);
511 		if (t) {
512 			leaf = false;
513 			cpu = get_cpu_for_node(t);
514 			if (cpu >= 0) {
515 				cpu_topology[cpu].package_id = package_id;
516 				cpu_topology[cpu].cluster_id = cluster_id;
517 				cpu_topology[cpu].core_id = core_id;
518 				cpu_topology[cpu].thread_id = i;
519 			} else if (cpu != -ENODEV) {
520 				pr_err("%pOF: Can't get CPU for thread\n", t);
521 				of_node_put(t);
522 				return -EINVAL;
523 			}
524 			of_node_put(t);
525 		}
526 		i++;
527 	} while (t);
528 
529 	cpu = get_cpu_for_node(core);
530 	if (cpu >= 0) {
531 		if (!leaf) {
532 			pr_err("%pOF: Core has both threads and CPU\n",
533 			       core);
534 			return -EINVAL;
535 		}
536 
537 		cpu_topology[cpu].package_id = package_id;
538 		cpu_topology[cpu].cluster_id = cluster_id;
539 		cpu_topology[cpu].core_id = core_id;
540 	} else if (leaf && cpu != -ENODEV) {
541 		pr_err("%pOF: Can't get CPU for leaf core\n", core);
542 		return -EINVAL;
543 	}
544 
545 	return 0;
546 }
547 
548 static int __init parse_cluster(struct device_node *cluster, int package_id,
549 				int cluster_id, int depth)
550 {
551 	char name[20];
552 	bool leaf = true;
553 	bool has_cores = false;
554 	struct device_node *c;
555 	int core_id = 0;
556 	int i, ret;
557 
558 	/*
559 	 * First check for child clusters; we currently ignore any
560 	 * information about the nesting of clusters and present the
561 	 * scheduler with a flat list of them.
562 	 */
563 	i = 0;
564 	do {
565 		snprintf(name, sizeof(name), "cluster%d", i);
566 		c = of_get_child_by_name(cluster, name);
567 		if (c) {
568 			leaf = false;
569 			ret = parse_cluster(c, package_id, i, depth + 1);
570 			if (depth > 0)
571 				pr_warn("Topology for clusters of clusters not yet supported\n");
572 			of_node_put(c);
573 			if (ret != 0)
574 				return ret;
575 		}
576 		i++;
577 	} while (c);
578 
579 	/* Now check for cores */
580 	i = 0;
581 	do {
582 		snprintf(name, sizeof(name), "core%d", i);
583 		c = of_get_child_by_name(cluster, name);
584 		if (c) {
585 			has_cores = true;
586 
587 			if (depth == 0) {
588 				pr_err("%pOF: cpu-map children should be clusters\n",
589 				       c);
590 				of_node_put(c);
591 				return -EINVAL;
592 			}
593 
594 			if (leaf) {
595 				ret = parse_core(c, package_id, cluster_id,
596 						 core_id++);
597 			} else {
598 				pr_err("%pOF: Non-leaf cluster with core %s\n",
599 				       cluster, name);
600 				ret = -EINVAL;
601 			}
602 
603 			of_node_put(c);
604 			if (ret != 0)
605 				return ret;
606 		}
607 		i++;
608 	} while (c);
609 
610 	if (leaf && !has_cores)
611 		pr_warn("%pOF: empty cluster\n", cluster);
612 
613 	return 0;
614 }
615 
616 static int __init parse_socket(struct device_node *socket)
617 {
618 	char name[20];
619 	struct device_node *c;
620 	bool has_socket = false;
621 	int package_id = 0, ret;
622 
623 	do {
624 		snprintf(name, sizeof(name), "socket%d", package_id);
625 		c = of_get_child_by_name(socket, name);
626 		if (c) {
627 			has_socket = true;
628 			ret = parse_cluster(c, package_id, -1, 0);
629 			of_node_put(c);
630 			if (ret != 0)
631 				return ret;
632 		}
633 		package_id++;
634 	} while (c);
635 
636 	if (!has_socket)
637 		ret = parse_cluster(socket, 0, -1, 0);
638 
639 	return ret;
640 }
641 
642 static int __init parse_dt_topology(void)
643 {
644 	struct device_node *cn, *map;
645 	int ret = 0;
646 	int cpu;
647 
648 	cn = of_find_node_by_path("/cpus");
649 	if (!cn) {
650 		pr_err("No CPU information found in DT\n");
651 		return 0;
652 	}
653 
654 	/*
655 	 * When topology is provided cpu-map is essentially a root
656 	 * cluster with restricted subnodes.
657 	 */
658 	map = of_get_child_by_name(cn, "cpu-map");
659 	if (!map)
660 		goto out;
661 
662 	ret = parse_socket(map);
663 	if (ret != 0)
664 		goto out_map;
665 
666 	topology_normalize_cpu_scale();
667 
668 	/*
669 	 * Check that all cores are in the topology; the SMP code will
670 	 * only mark cores described in the DT as possible.
671 	 */
672 	for_each_possible_cpu(cpu)
673 		if (cpu_topology[cpu].package_id < 0) {
674 			ret = -EINVAL;
675 			break;
676 		}
677 
678 out_map:
679 	of_node_put(map);
680 out:
681 	of_node_put(cn);
682 	return ret;
683 }
684 #endif
685 
686 /*
687  * cpu topology table
688  */
689 struct cpu_topology cpu_topology[NR_CPUS];
690 EXPORT_SYMBOL_GPL(cpu_topology);
691 
692 const struct cpumask *cpu_coregroup_mask(int cpu)
693 {
694 	const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));
695 
696 	/* Find the smaller of NUMA, core or LLC siblings */
697 	if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
698 		/* not numa in package, lets use the package siblings */
699 		core_mask = &cpu_topology[cpu].core_sibling;
700 	}
701 
702 	if (last_level_cache_is_valid(cpu)) {
703 		if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
704 			core_mask = &cpu_topology[cpu].llc_sibling;
705 	}
706 
707 	/*
708 	 * For systems with no shared cpu-side LLC but with clusters defined,
709 	 * extend core_mask to cluster_siblings. The sched domain builder will
710 	 * then remove MC as redundant with CLS if SCHED_CLUSTER is enabled.
711 	 */
712 	if (IS_ENABLED(CONFIG_SCHED_CLUSTER) &&
713 	    cpumask_subset(core_mask, &cpu_topology[cpu].cluster_sibling))
714 		core_mask = &cpu_topology[cpu].cluster_sibling;
715 
716 	return core_mask;
717 }
718 
719 const struct cpumask *cpu_clustergroup_mask(int cpu)
720 {
721 	/*
722 	 * Forbid cpu_clustergroup_mask() to span more or the same CPUs as
723 	 * cpu_coregroup_mask().
724 	 */
725 	if (cpumask_subset(cpu_coregroup_mask(cpu),
726 			   &cpu_topology[cpu].cluster_sibling))
727 		return topology_sibling_cpumask(cpu);
728 
729 	return &cpu_topology[cpu].cluster_sibling;
730 }
731 
732 void update_siblings_masks(unsigned int cpuid)
733 {
734 	struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
735 	int cpu, ret;
736 
737 	ret = detect_cache_attributes(cpuid);
738 	if (ret && ret != -ENOENT)
739 		pr_info("Early cacheinfo allocation failed, ret = %d\n", ret);
740 
741 	/* update core and thread sibling masks */
742 	for_each_online_cpu(cpu) {
743 		cpu_topo = &cpu_topology[cpu];
744 
745 		if (last_level_cache_is_shared(cpu, cpuid)) {
746 			cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
747 			cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
748 		}
749 
750 		if (cpuid_topo->package_id != cpu_topo->package_id)
751 			continue;
752 
753 		cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
754 		cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
755 
756 		if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
757 			continue;
758 
759 		if (cpuid_topo->cluster_id >= 0) {
760 			cpumask_set_cpu(cpu, &cpuid_topo->cluster_sibling);
761 			cpumask_set_cpu(cpuid, &cpu_topo->cluster_sibling);
762 		}
763 
764 		if (cpuid_topo->core_id != cpu_topo->core_id)
765 			continue;
766 
767 		cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
768 		cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
769 	}
770 }
771 
772 static void clear_cpu_topology(int cpu)
773 {
774 	struct cpu_topology *cpu_topo = &cpu_topology[cpu];
775 
776 	cpumask_clear(&cpu_topo->llc_sibling);
777 	cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);
778 
779 	cpumask_clear(&cpu_topo->cluster_sibling);
780 	cpumask_set_cpu(cpu, &cpu_topo->cluster_sibling);
781 
782 	cpumask_clear(&cpu_topo->core_sibling);
783 	cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
784 	cpumask_clear(&cpu_topo->thread_sibling);
785 	cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
786 }
787 
788 void __init reset_cpu_topology(void)
789 {
790 	unsigned int cpu;
791 
792 	for_each_possible_cpu(cpu) {
793 		struct cpu_topology *cpu_topo = &cpu_topology[cpu];
794 
795 		cpu_topo->thread_id = -1;
796 		cpu_topo->core_id = -1;
797 		cpu_topo->cluster_id = -1;
798 		cpu_topo->package_id = -1;
799 
800 		clear_cpu_topology(cpu);
801 	}
802 }
803 
804 void remove_cpu_topology(unsigned int cpu)
805 {
806 	int sibling;
807 
808 	for_each_cpu(sibling, topology_core_cpumask(cpu))
809 		cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
810 	for_each_cpu(sibling, topology_sibling_cpumask(cpu))
811 		cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
812 	for_each_cpu(sibling, topology_cluster_cpumask(cpu))
813 		cpumask_clear_cpu(cpu, topology_cluster_cpumask(sibling));
814 	for_each_cpu(sibling, topology_llc_cpumask(cpu))
815 		cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));
816 
817 	clear_cpu_topology(cpu);
818 }
819 
820 __weak int __init parse_acpi_topology(void)
821 {
822 	return 0;
823 }
824 
825 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
826 void __init init_cpu_topology(void)
827 {
828 	int cpu, ret;
829 
830 	reset_cpu_topology();
831 	ret = parse_acpi_topology();
832 	if (!ret)
833 		ret = of_have_populated_dt() && parse_dt_topology();
834 
835 	if (ret) {
836 		/*
837 		 * Discard anything that was parsed if we hit an error so we
838 		 * don't use partial information. But do not return yet to give
839 		 * arch-specific early cache level detection a chance to run.
840 		 */
841 		reset_cpu_topology();
842 	}
843 
844 	for_each_possible_cpu(cpu) {
845 		ret = fetch_cache_info(cpu);
846 		if (!ret)
847 			continue;
848 		else if (ret != -ENOENT)
849 			pr_err("Early cacheinfo failed, ret = %d\n", ret);
850 		return;
851 	}
852 }
853 
854 void store_cpu_topology(unsigned int cpuid)
855 {
856 	struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
857 
858 	if (cpuid_topo->package_id != -1)
859 		goto topology_populated;
860 
861 	cpuid_topo->thread_id = -1;
862 	cpuid_topo->core_id = cpuid;
863 	cpuid_topo->package_id = cpu_to_node(cpuid);
864 
865 	pr_debug("CPU%u: package %d core %d thread %d\n",
866 		 cpuid, cpuid_topo->package_id, cpuid_topo->core_id,
867 		 cpuid_topo->thread_id);
868 
869 topology_populated:
870 	update_siblings_masks(cpuid);
871 }
872 #endif
873