2 * Copyright IBM Corp. 2007, 2011
3 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
6 #define KMSG_COMPONENT "cpu"
7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9 #include <linux/workqueue.h>
10 #include <linux/bootmem.h>
11 #include <linux/cpuset.h>
12 #include <linux/device.h>
13 #include <linux/export.h>
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/cpu.h>
19 #include <linux/smp.h>
21 #include <asm/sysinfo.h>
23 #define PTF_HORIZONTAL (0UL)
24 #define PTF_VERTICAL (1UL)
25 #define PTF_CHECK (2UL)
28 struct mask_info *next;
33 static void set_topology_timer(void);
34 static void topology_work_fn(struct work_struct *work);
35 static struct sysinfo_15_1_x *tl_info;
37 static int topology_enabled = 1;
38 static DECLARE_WORK(topology_work, topology_work_fn);
40 /* topology_lock protects the socket and book linked lists */
41 static DEFINE_SPINLOCK(topology_lock);
42 static struct mask_info socket_info;
43 static struct mask_info book_info;
45 struct cpu_topology_s390 cpu_topology[NR_CPUS];
46 EXPORT_SYMBOL_GPL(cpu_topology);
48 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
52 cpumask_copy(&mask, cpumask_of(cpu));
53 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY)
55 for (; info; info = info->next) {
56 if (cpumask_test_cpu(cpu, &info->mask))
62 static struct mask_info *add_cpus_to_mask(struct topology_cpu *tl_cpu,
63 struct mask_info *book,
64 struct mask_info *socket,
65 int one_socket_per_cpu)
69 for_each_set_bit(cpu, &tl_cpu->mask[0], TOPOLOGY_CPU_BITS) {
73 rcpu = TOPOLOGY_CPU_BITS - 1 - cpu + tl_cpu->origin;
74 lcpu = smp_find_processor_id(rcpu);
77 cpumask_set_cpu(lcpu, &book->mask);
78 cpu_topology[lcpu].book_id = book->id;
79 cpumask_set_cpu(lcpu, &socket->mask);
80 cpu_topology[lcpu].core_id = rcpu;
81 if (one_socket_per_cpu) {
82 cpu_topology[lcpu].socket_id = rcpu;
83 socket = socket->next;
85 cpu_topology[lcpu].socket_id = socket->id;
87 smp_cpu_set_polarization(lcpu, tl_cpu->pp);
92 static void clear_masks(void)
94 struct mask_info *info;
98 cpumask_clear(&info->mask);
103 cpumask_clear(&info->mask);
108 static union topology_entry *next_tle(union topology_entry *tle)
111 return (union topology_entry *)((struct topology_cpu *)tle + 1);
112 return (union topology_entry *)((struct topology_container *)tle + 1);
115 static void __tl_to_masks_generic(struct sysinfo_15_1_x *info)
117 struct mask_info *socket = &socket_info;
118 struct mask_info *book = &book_info;
119 union topology_entry *tle, *end;
122 end = (union topology_entry *)((unsigned long)info + info->length);
127 book->id = tle->container.id;
130 socket = socket->next;
131 socket->id = tle->container.id;
134 add_cpus_to_mask(&tle->cpu, book, socket, 0);
144 static void __tl_to_masks_z10(struct sysinfo_15_1_x *info)
146 struct mask_info *socket = &socket_info;
147 struct mask_info *book = &book_info;
148 union topology_entry *tle, *end;
151 end = (union topology_entry *)((unsigned long)info + info->length);
156 book->id = tle->container.id;
159 socket = add_cpus_to_mask(&tle->cpu, book, socket, 1);
169 static void tl_to_masks(struct sysinfo_15_1_x *info)
173 spin_lock_irq(&topology_lock);
176 switch (cpu_id.machine) {
179 __tl_to_masks_z10(info);
182 __tl_to_masks_generic(info);
184 spin_unlock_irq(&topology_lock);
187 static void topology_update_polarization_simple(void)
191 mutex_lock(&smp_cpu_state_mutex);
192 for_each_possible_cpu(cpu)
193 smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
194 mutex_unlock(&smp_cpu_state_mutex);
197 static int ptf(unsigned long fc)
202 " .insn rre,0xb9a20000,%1,%1\n"
210 int topology_set_cpu_management(int fc)
214 if (!MACHINE_HAS_TOPOLOGY)
217 rc = ptf(PTF_VERTICAL);
219 rc = ptf(PTF_HORIZONTAL);
222 for_each_possible_cpu(cpu)
223 smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
227 static void update_cpu_masks(void)
232 spin_lock_irqsave(&topology_lock, flags);
233 for_each_possible_cpu(cpu) {
234 cpu_topology[cpu].core_mask = cpu_group_map(&socket_info, cpu);
235 cpu_topology[cpu].book_mask = cpu_group_map(&book_info, cpu);
236 if (!MACHINE_HAS_TOPOLOGY) {
237 cpu_topology[cpu].core_id = cpu;
238 cpu_topology[cpu].socket_id = cpu;
239 cpu_topology[cpu].book_id = cpu;
242 spin_unlock_irqrestore(&topology_lock, flags);
245 void store_topology(struct sysinfo_15_1_x *info)
247 if (topology_max_mnest >= 3)
248 stsi(info, 15, 1, 3);
250 stsi(info, 15, 1, 2);
253 int arch_update_cpu_topology(void)
255 struct sysinfo_15_1_x *info = tl_info;
259 if (!MACHINE_HAS_TOPOLOGY) {
261 topology_update_polarization_simple();
264 store_topology(info);
267 for_each_online_cpu(cpu) {
268 dev = get_cpu_device(cpu);
270 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
275 static void topology_work_fn(struct work_struct *work)
277 rebuild_sched_domains();
280 void topology_schedule_update(void)
282 schedule_work(&topology_work);
285 static void topology_timer_fn(unsigned long ignored)
288 topology_schedule_update();
289 set_topology_timer();
292 static struct timer_list topology_timer =
293 TIMER_DEFERRED_INITIALIZER(topology_timer_fn, 0, 0);
295 static atomic_t topology_poll = ATOMIC_INIT(0);
297 static void set_topology_timer(void)
299 if (atomic_add_unless(&topology_poll, -1, 0))
300 mod_timer(&topology_timer, jiffies + HZ / 10);
302 mod_timer(&topology_timer, jiffies + HZ * 60);
305 void topology_expect_change(void)
307 if (!MACHINE_HAS_TOPOLOGY)
309 /* This is racy, but it doesn't matter since it is just a heuristic.
310 * Worst case is that we poll in a higher frequency for a bit longer.
312 if (atomic_read(&topology_poll) > 60)
314 atomic_add(60, &topology_poll);
315 set_topology_timer();
318 static int __init early_parse_topology(char *p)
320 if (strncmp(p, "off", 3))
322 topology_enabled = 0;
325 early_param("topology", early_parse_topology);
327 static void __init alloc_masks(struct sysinfo_15_1_x *info,
328 struct mask_info *mask, int offset)
332 nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
333 for (i = 0; i < info->mnest - offset; i++)
334 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
335 nr_masks = max(nr_masks, 1);
336 for (i = 0; i < nr_masks; i++) {
337 mask->next = alloc_bootmem_align(
338 roundup_pow_of_two(sizeof(struct mask_info)),
339 roundup_pow_of_two(sizeof(struct mask_info)));
344 void __init s390_init_cpu_topology(void)
346 struct sysinfo_15_1_x *info;
349 if (!MACHINE_HAS_TOPOLOGY)
351 tl_info = alloc_bootmem_pages(PAGE_SIZE);
353 store_topology(info);
354 pr_info("The CPU configuration topology of the machine is:");
355 for (i = 0; i < TOPOLOGY_NR_MAG; i++)
356 printk(KERN_CONT " %d", info->mag[i]);
357 printk(KERN_CONT " / %d\n", info->mnest);
358 alloc_masks(info, &socket_info, 1);
359 alloc_masks(info, &book_info, 2);
362 static int cpu_management;
364 static ssize_t dispatching_show(struct device *dev,
365 struct device_attribute *attr,
370 mutex_lock(&smp_cpu_state_mutex);
371 count = sprintf(buf, "%d\n", cpu_management);
372 mutex_unlock(&smp_cpu_state_mutex);
376 static ssize_t dispatching_store(struct device *dev,
377 struct device_attribute *attr,
384 if (sscanf(buf, "%d %c", &val, &delim) != 1)
386 if (val != 0 && val != 1)
390 mutex_lock(&smp_cpu_state_mutex);
391 if (cpu_management == val)
393 rc = topology_set_cpu_management(val);
396 cpu_management = val;
397 topology_expect_change();
399 mutex_unlock(&smp_cpu_state_mutex);
401 return rc ? rc : count;
403 static DEVICE_ATTR(dispatching, 0644, dispatching_show,
406 static ssize_t cpu_polarization_show(struct device *dev,
407 struct device_attribute *attr, char *buf)
412 mutex_lock(&smp_cpu_state_mutex);
413 switch (smp_cpu_get_polarization(cpu)) {
414 case POLARIZATION_HRZ:
415 count = sprintf(buf, "horizontal\n");
417 case POLARIZATION_VL:
418 count = sprintf(buf, "vertical:low\n");
420 case POLARIZATION_VM:
421 count = sprintf(buf, "vertical:medium\n");
423 case POLARIZATION_VH:
424 count = sprintf(buf, "vertical:high\n");
427 count = sprintf(buf, "unknown\n");
430 mutex_unlock(&smp_cpu_state_mutex);
433 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);
435 static struct attribute *topology_cpu_attrs[] = {
436 &dev_attr_polarization.attr,
440 static struct attribute_group topology_cpu_attr_group = {
441 .attrs = topology_cpu_attrs,
444 int topology_cpu_init(struct cpu *cpu)
446 return sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
449 const struct cpumask *cpu_coregroup_mask(int cpu)
451 return &cpu_topology[cpu].core_mask;
454 static const struct cpumask *cpu_book_mask(int cpu)
456 return &cpu_topology[cpu].book_mask;
459 static struct sched_domain_topology_level s390_topology[] = {
460 { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
461 { cpu_book_mask, SD_INIT_NAME(BOOK) },
462 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
466 static int __init topology_init(void)
468 if (MACHINE_HAS_TOPOLOGY)
469 set_topology_timer();
471 topology_update_polarization_simple();
472 return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
474 device_initcall(topology_init);
476 static int __init early_topology_init(void)
478 set_sched_topology(s390_topology);
481 early_initcall(early_topology_init);