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/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/init.h>
16 #include <linux/delay.h>
17 #include <linux/cpu.h>
18 #include <linux/smp.h>
20 #include <asm/sysinfo.h>
22 #define PTF_HORIZONTAL (0UL)
23 #define PTF_VERTICAL (1UL)
24 #define PTF_CHECK (2UL)
27 struct mask_info *next;
32 static int topology_enabled = 1;
33 static void topology_work_fn(struct work_struct *work);
34 static struct sysinfo_15_1_x *tl_info;
35 static void set_topology_timer(void);
36 static DECLARE_WORK(topology_work, topology_work_fn);
37 /* topology_lock protects the core linked list */
38 static DEFINE_SPINLOCK(topology_lock);
40 static struct mask_info core_info;
41 cpumask_t cpu_core_map[NR_CPUS];
42 unsigned char cpu_core_id[NR_CPUS];
44 static struct mask_info book_info;
45 cpumask_t cpu_book_map[NR_CPUS];
46 unsigned char cpu_book_id[NR_CPUS];
48 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
53 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY) {
54 cpumask_copy(&mask, cpumask_of(cpu));
58 if (cpumask_test_cpu(cpu, &info->mask)) {
64 if (cpumask_empty(&mask))
65 cpumask_copy(&mask, cpumask_of(cpu));
69 static struct mask_info *add_cpus_to_mask(struct topology_cpu *tl_cpu,
70 struct mask_info *book,
71 struct mask_info *core,
76 for_each_set_bit(cpu, &tl_cpu->mask[0], TOPOLOGY_CPU_BITS) {
80 rcpu = TOPOLOGY_CPU_BITS - 1 - cpu + tl_cpu->origin;
81 lcpu = smp_find_processor_id(rcpu);
83 cpumask_set_cpu(lcpu, &book->mask);
84 cpu_book_id[lcpu] = book->id;
85 cpumask_set_cpu(lcpu, &core->mask);
86 if (one_core_per_cpu) {
87 cpu_core_id[lcpu] = rcpu;
90 cpu_core_id[lcpu] = core->id;
92 smp_cpu_set_polarization(lcpu, tl_cpu->pp);
98 static void clear_masks(void)
100 struct mask_info *info;
104 cpumask_clear(&info->mask);
109 cpumask_clear(&info->mask);
114 static union topology_entry *next_tle(union topology_entry *tle)
117 return (union topology_entry *)((struct topology_cpu *)tle + 1);
118 return (union topology_entry *)((struct topology_container *)tle + 1);
121 static void __tl_to_cores_generic(struct sysinfo_15_1_x *info)
123 struct mask_info *core = &core_info;
124 struct mask_info *book = &book_info;
125 union topology_entry *tle, *end;
128 end = (union topology_entry *)((unsigned long)info + info->length);
133 book->id = tle->container.id;
137 core->id = tle->container.id;
140 add_cpus_to_mask(&tle->cpu, book, core, 0);
150 static void __tl_to_cores_z10(struct sysinfo_15_1_x *info)
152 struct mask_info *core = &core_info;
153 struct mask_info *book = &book_info;
154 union topology_entry *tle, *end;
157 end = (union topology_entry *)((unsigned long)info + info->length);
162 book->id = tle->container.id;
165 core = add_cpus_to_mask(&tle->cpu, book, core, 1);
175 static void tl_to_cores(struct sysinfo_15_1_x *info)
180 spin_lock_irq(&topology_lock);
182 switch (cpu_id.machine) {
185 __tl_to_cores_z10(info);
188 __tl_to_cores_generic(info);
190 spin_unlock_irq(&topology_lock);
193 static void topology_update_polarization_simple(void)
197 mutex_lock(&smp_cpu_state_mutex);
198 for_each_possible_cpu(cpu)
199 smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
200 mutex_unlock(&smp_cpu_state_mutex);
203 static int ptf(unsigned long fc)
208 " .insn rre,0xb9a20000,%1,%1\n"
216 int topology_set_cpu_management(int fc)
220 if (!MACHINE_HAS_TOPOLOGY)
223 rc = ptf(PTF_VERTICAL);
225 rc = ptf(PTF_HORIZONTAL);
228 for_each_possible_cpu(cpu)
229 smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
233 static void update_cpu_core_map(void)
238 spin_lock_irqsave(&topology_lock, flags);
239 for_each_possible_cpu(cpu) {
240 cpu_core_map[cpu] = cpu_group_map(&core_info, cpu);
241 cpu_book_map[cpu] = cpu_group_map(&book_info, cpu);
243 spin_unlock_irqrestore(&topology_lock, flags);
246 void store_topology(struct sysinfo_15_1_x *info)
248 if (topology_max_mnest >= 3)
249 stsi(info, 15, 1, 3);
251 stsi(info, 15, 1, 2);
254 int arch_update_cpu_topology(void)
256 struct sysinfo_15_1_x *info = tl_info;
260 if (!MACHINE_HAS_TOPOLOGY) {
261 update_cpu_core_map();
262 topology_update_polarization_simple();
265 store_topology(info);
267 update_cpu_core_map();
268 for_each_online_cpu(cpu) {
269 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(sizeof(struct mask_info));
342 void __init s390_init_cpu_topology(void)
344 struct sysinfo_15_1_x *info;
347 if (!MACHINE_HAS_TOPOLOGY)
349 tl_info = alloc_bootmem_pages(PAGE_SIZE);
351 store_topology(info);
352 pr_info("The CPU configuration topology of the machine is:");
353 for (i = 0; i < TOPOLOGY_NR_MAG; i++)
354 printk(KERN_CONT " %d", info->mag[i]);
355 printk(KERN_CONT " / %d\n", info->mnest);
356 alloc_masks(info, &core_info, 1);
357 alloc_masks(info, &book_info, 2);
360 static int cpu_management;
362 static ssize_t dispatching_show(struct device *dev,
363 struct device_attribute *attr,
368 mutex_lock(&smp_cpu_state_mutex);
369 count = sprintf(buf, "%d\n", cpu_management);
370 mutex_unlock(&smp_cpu_state_mutex);
374 static ssize_t dispatching_store(struct device *dev,
375 struct device_attribute *attr,
382 if (sscanf(buf, "%d %c", &val, &delim) != 1)
384 if (val != 0 && val != 1)
388 mutex_lock(&smp_cpu_state_mutex);
389 if (cpu_management == val)
391 rc = topology_set_cpu_management(val);
394 cpu_management = val;
395 topology_expect_change();
397 mutex_unlock(&smp_cpu_state_mutex);
399 return rc ? rc : count;
401 static DEVICE_ATTR(dispatching, 0644, dispatching_show,
404 static ssize_t cpu_polarization_show(struct device *dev,
405 struct device_attribute *attr, char *buf)
410 mutex_lock(&smp_cpu_state_mutex);
411 switch (smp_cpu_get_polarization(cpu)) {
412 case POLARIZATION_HRZ:
413 count = sprintf(buf, "horizontal\n");
415 case POLARIZATION_VL:
416 count = sprintf(buf, "vertical:low\n");
418 case POLARIZATION_VM:
419 count = sprintf(buf, "vertical:medium\n");
421 case POLARIZATION_VH:
422 count = sprintf(buf, "vertical:high\n");
425 count = sprintf(buf, "unknown\n");
428 mutex_unlock(&smp_cpu_state_mutex);
431 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);
433 static struct attribute *topology_cpu_attrs[] = {
434 &dev_attr_polarization.attr,
438 static struct attribute_group topology_cpu_attr_group = {
439 .attrs = topology_cpu_attrs,
442 int topology_cpu_init(struct cpu *cpu)
444 return sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
447 static int __init topology_init(void)
449 if (!MACHINE_HAS_TOPOLOGY) {
450 topology_update_polarization_simple();
453 set_topology_timer();
455 update_cpu_core_map();
456 return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
458 device_initcall(topology_init);