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/cpuset.h>
11 #include <linux/device.h>
12 #include <linux/export.h>
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/cpu.h>
19 #include <linux/smp.h>
21 #include <linux/nodemask.h>
22 #include <linux/node.h>
23 #include <asm/sysinfo.h>
26 #define PTF_HORIZONTAL (0UL)
27 #define PTF_VERTICAL (1UL)
28 #define PTF_CHECK (2UL)
31 struct mask_info *next;
36 static void set_topology_timer(void);
37 static void topology_work_fn(struct work_struct *work);
38 static struct sysinfo_15_1_x *tl_info;
40 static bool topology_enabled = true;
41 static DECLARE_WORK(topology_work, topology_work_fn);
44 * Socket/Book linked lists and per_cpu(cpu_topology) updates are
45 * protected by "sched_domains_mutex".
47 static struct mask_info socket_info;
48 static struct mask_info book_info;
49 static struct mask_info drawer_info;
51 DEFINE_PER_CPU(struct cpu_topology_s390, cpu_topology);
52 EXPORT_PER_CPU_SYMBOL_GPL(cpu_topology);
54 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
58 cpumask_copy(&mask, cpumask_of(cpu));
59 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY)
61 for (; info; info = info->next) {
62 if (cpumask_test_cpu(cpu, &info->mask))
68 static cpumask_t cpu_thread_map(unsigned int cpu)
73 cpumask_copy(&mask, cpumask_of(cpu));
74 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY)
76 cpu -= cpu % (smp_cpu_mtid + 1);
77 for (i = 0; i <= smp_cpu_mtid; i++)
78 if (cpu_present(cpu + i))
79 cpumask_set_cpu(cpu + i, &mask);
83 static void add_cpus_to_mask(struct topology_core *tl_core,
84 struct mask_info *drawer,
85 struct mask_info *book,
86 struct mask_info *socket)
88 struct cpu_topology_s390 *topo;
91 for_each_set_bit(core, &tl_core->mask[0], TOPOLOGY_CORE_BITS) {
95 rcore = TOPOLOGY_CORE_BITS - 1 - core + tl_core->origin;
96 lcpu = smp_find_processor_id(rcore << smp_cpu_mt_shift);
99 for (i = 0; i <= smp_cpu_mtid; i++) {
100 topo = &per_cpu(cpu_topology, lcpu + i);
101 topo->drawer_id = drawer->id;
102 topo->book_id = book->id;
103 topo->socket_id = socket->id;
104 topo->core_id = rcore;
105 topo->thread_id = lcpu + i;
106 cpumask_set_cpu(lcpu + i, &drawer->mask);
107 cpumask_set_cpu(lcpu + i, &book->mask);
108 cpumask_set_cpu(lcpu + i, &socket->mask);
109 smp_cpu_set_polarization(lcpu + i, tl_core->pp);
114 static void clear_masks(void)
116 struct mask_info *info;
120 cpumask_clear(&info->mask);
125 cpumask_clear(&info->mask);
130 cpumask_clear(&info->mask);
135 static union topology_entry *next_tle(union topology_entry *tle)
138 return (union topology_entry *)((struct topology_core *)tle + 1);
139 return (union topology_entry *)((struct topology_container *)tle + 1);
142 static void tl_to_masks(struct sysinfo_15_1_x *info)
144 struct mask_info *socket = &socket_info;
145 struct mask_info *book = &book_info;
146 struct mask_info *drawer = &drawer_info;
147 union topology_entry *tle, *end;
151 end = (union topology_entry *)((unsigned long)info + info->length);
155 drawer = drawer->next;
156 drawer->id = tle->container.id;
160 book->id = tle->container.id;
163 socket = socket->next;
164 socket->id = tle->container.id;
167 add_cpus_to_mask(&tle->cpu, drawer, book, socket);
177 static void topology_update_polarization_simple(void)
181 mutex_lock(&smp_cpu_state_mutex);
182 for_each_possible_cpu(cpu)
183 smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
184 mutex_unlock(&smp_cpu_state_mutex);
187 static int ptf(unsigned long fc)
192 " .insn rre,0xb9a20000,%1,%1\n"
200 int topology_set_cpu_management(int fc)
204 if (!MACHINE_HAS_TOPOLOGY)
207 rc = ptf(PTF_VERTICAL);
209 rc = ptf(PTF_HORIZONTAL);
212 for_each_possible_cpu(cpu)
213 smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
217 static void update_cpu_masks(void)
219 struct cpu_topology_s390 *topo;
222 for_each_possible_cpu(cpu) {
223 topo = &per_cpu(cpu_topology, cpu);
224 topo->thread_mask = cpu_thread_map(cpu);
225 topo->core_mask = cpu_group_map(&socket_info, cpu);
226 topo->book_mask = cpu_group_map(&book_info, cpu);
227 topo->drawer_mask = cpu_group_map(&drawer_info, cpu);
228 if (!MACHINE_HAS_TOPOLOGY) {
229 topo->thread_id = cpu;
231 topo->socket_id = cpu;
233 topo->drawer_id = cpu;
236 numa_update_cpu_topology();
239 void store_topology(struct sysinfo_15_1_x *info)
241 stsi(info, 15, 1, min(topology_max_mnest, 4));
244 int arch_update_cpu_topology(void)
246 struct sysinfo_15_1_x *info = tl_info;
250 if (MACHINE_HAS_TOPOLOGY) {
252 store_topology(info);
256 if (!MACHINE_HAS_TOPOLOGY)
257 topology_update_polarization_simple();
258 for_each_online_cpu(cpu) {
259 dev = get_cpu_device(cpu);
260 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
265 static void topology_work_fn(struct work_struct *work)
267 rebuild_sched_domains();
270 void topology_schedule_update(void)
272 schedule_work(&topology_work);
275 static void topology_timer_fn(unsigned long ignored)
278 topology_schedule_update();
279 set_topology_timer();
282 static struct timer_list topology_timer =
283 TIMER_DEFERRED_INITIALIZER(topology_timer_fn, 0, 0);
285 static atomic_t topology_poll = ATOMIC_INIT(0);
287 static void set_topology_timer(void)
289 if (atomic_add_unless(&topology_poll, -1, 0))
290 mod_timer(&topology_timer, jiffies + HZ / 10);
292 mod_timer(&topology_timer, jiffies + HZ * 60);
295 void topology_expect_change(void)
297 if (!MACHINE_HAS_TOPOLOGY)
299 /* This is racy, but it doesn't matter since it is just a heuristic.
300 * Worst case is that we poll in a higher frequency for a bit longer.
302 if (atomic_read(&topology_poll) > 60)
304 atomic_add(60, &topology_poll);
305 set_topology_timer();
308 static int cpu_management;
310 static ssize_t dispatching_show(struct device *dev,
311 struct device_attribute *attr,
316 mutex_lock(&smp_cpu_state_mutex);
317 count = sprintf(buf, "%d\n", cpu_management);
318 mutex_unlock(&smp_cpu_state_mutex);
322 static ssize_t dispatching_store(struct device *dev,
323 struct device_attribute *attr,
330 if (sscanf(buf, "%d %c", &val, &delim) != 1)
332 if (val != 0 && val != 1)
336 mutex_lock(&smp_cpu_state_mutex);
337 if (cpu_management == val)
339 rc = topology_set_cpu_management(val);
342 cpu_management = val;
343 topology_expect_change();
345 mutex_unlock(&smp_cpu_state_mutex);
347 return rc ? rc : count;
349 static DEVICE_ATTR(dispatching, 0644, dispatching_show,
352 static ssize_t cpu_polarization_show(struct device *dev,
353 struct device_attribute *attr, char *buf)
358 mutex_lock(&smp_cpu_state_mutex);
359 switch (smp_cpu_get_polarization(cpu)) {
360 case POLARIZATION_HRZ:
361 count = sprintf(buf, "horizontal\n");
363 case POLARIZATION_VL:
364 count = sprintf(buf, "vertical:low\n");
366 case POLARIZATION_VM:
367 count = sprintf(buf, "vertical:medium\n");
369 case POLARIZATION_VH:
370 count = sprintf(buf, "vertical:high\n");
373 count = sprintf(buf, "unknown\n");
376 mutex_unlock(&smp_cpu_state_mutex);
379 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);
381 static struct attribute *topology_cpu_attrs[] = {
382 &dev_attr_polarization.attr,
386 static struct attribute_group topology_cpu_attr_group = {
387 .attrs = topology_cpu_attrs,
390 int topology_cpu_init(struct cpu *cpu)
392 return sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
395 static const struct cpumask *cpu_thread_mask(int cpu)
397 return &per_cpu(cpu_topology, cpu).thread_mask;
401 const struct cpumask *cpu_coregroup_mask(int cpu)
403 return &per_cpu(cpu_topology, cpu).core_mask;
406 static const struct cpumask *cpu_book_mask(int cpu)
408 return &per_cpu(cpu_topology, cpu).book_mask;
411 static const struct cpumask *cpu_drawer_mask(int cpu)
413 return &per_cpu(cpu_topology, cpu).drawer_mask;
416 static int __init early_parse_topology(char *p)
418 return kstrtobool(p, &topology_enabled);
420 early_param("topology", early_parse_topology);
422 static struct sched_domain_topology_level s390_topology[] = {
423 { cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
424 { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
425 { cpu_book_mask, SD_INIT_NAME(BOOK) },
426 { cpu_drawer_mask, SD_INIT_NAME(DRAWER) },
427 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
431 static void __init alloc_masks(struct sysinfo_15_1_x *info,
432 struct mask_info *mask, int offset)
436 nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
437 for (i = 0; i < info->mnest - offset; i++)
438 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
439 nr_masks = max(nr_masks, 1);
440 for (i = 0; i < nr_masks; i++) {
441 mask->next = kzalloc(sizeof(*mask->next), GFP_KERNEL);
446 static int __init s390_topology_init(void)
448 struct sysinfo_15_1_x *info;
451 if (!MACHINE_HAS_TOPOLOGY)
453 tl_info = (struct sysinfo_15_1_x *)__get_free_page(GFP_KERNEL);
455 store_topology(info);
456 pr_info("The CPU configuration topology of the machine is:");
457 for (i = 0; i < TOPOLOGY_NR_MAG; i++)
458 printk(KERN_CONT " %d", info->mag[i]);
459 printk(KERN_CONT " / %d\n", info->mnest);
460 alloc_masks(info, &socket_info, 1);
461 alloc_masks(info, &book_info, 2);
462 alloc_masks(info, &drawer_info, 3);
463 set_sched_topology(s390_topology);
466 early_initcall(s390_topology_init);
468 static int __init topology_init(void)
470 if (MACHINE_HAS_TOPOLOGY)
471 set_topology_timer();
473 topology_update_polarization_simple();
474 return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
476 device_initcall(topology_init);