1 /*
2 * Copyright IBM Corp. 2007, 2011
3 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
4 */
5
6 #define KMSG_COMPONENT "cpu"
7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
8
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>
20 #include <linux/mm.h>
21 #include <linux/nodemask.h>
22 #include <linux/node.h>
23 #include <asm/sysinfo.h>
24 #include <asm/numa.h>
25
26 #define PTF_HORIZONTAL (0UL)
27 #define PTF_VERTICAL (1UL)
28 #define PTF_CHECK (2UL)
29
30 struct mask_info {
31 struct mask_info *next;
32 unsigned char id;
33 cpumask_t mask;
34 };
35
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;
39
40 static int topology_enabled = 1;
41 static DECLARE_WORK(topology_work, topology_work_fn);
42
43 /*
44 * Socket/Book linked lists and per_cpu(cpu_topology) updates are
45 * protected by "sched_domains_mutex".
46 */
47 static struct mask_info socket_info;
48 static struct mask_info book_info;
49
50 DEFINE_PER_CPU(struct cpu_topology_s390, cpu_topology);
51 EXPORT_PER_CPU_SYMBOL_GPL(cpu_topology);
52
cpu_group_map(struct mask_info * info,unsigned int cpu)53 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
54 {
55 cpumask_t mask;
56
57 cpumask_copy(&mask, cpumask_of(cpu));
58 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY)
59 return mask;
60 for (; info; info = info->next) {
61 if (cpumask_test_cpu(cpu, &info->mask))
62 return info->mask;
63 }
64 return mask;
65 }
66
cpu_thread_map(unsigned int cpu)67 static cpumask_t cpu_thread_map(unsigned int cpu)
68 {
69 cpumask_t mask;
70 int i;
71
72 cpumask_copy(&mask, cpumask_of(cpu));
73 if (!topology_enabled || !MACHINE_HAS_TOPOLOGY)
74 return mask;
75 cpu -= cpu % (smp_cpu_mtid + 1);
76 for (i = 0; i <= smp_cpu_mtid; i++)
77 if (cpu_present(cpu + i))
78 cpumask_set_cpu(cpu + i, &mask);
79 return mask;
80 }
81
add_cpus_to_mask(struct topology_core * tl_core,struct mask_info * book,struct mask_info * socket,int one_socket_per_cpu)82 static struct mask_info *add_cpus_to_mask(struct topology_core *tl_core,
83 struct mask_info *book,
84 struct mask_info *socket,
85 int one_socket_per_cpu)
86 {
87 struct cpu_topology_s390 *topo;
88 unsigned int core;
89
90 for_each_set_bit(core, &tl_core->mask[0], TOPOLOGY_CORE_BITS) {
91 unsigned int rcore;
92 int lcpu, i;
93
94 rcore = TOPOLOGY_CORE_BITS - 1 - core + tl_core->origin;
95 lcpu = smp_find_processor_id(rcore << smp_cpu_mt_shift);
96 if (lcpu < 0)
97 continue;
98 for (i = 0; i <= smp_cpu_mtid; i++) {
99 topo = &per_cpu(cpu_topology, lcpu + i);
100 topo->book_id = book->id;
101 topo->core_id = rcore;
102 topo->thread_id = lcpu + i;
103 cpumask_set_cpu(lcpu + i, &book->mask);
104 cpumask_set_cpu(lcpu + i, &socket->mask);
105 if (one_socket_per_cpu)
106 topo->socket_id = rcore;
107 else
108 topo->socket_id = socket->id;
109 smp_cpu_set_polarization(lcpu + i, tl_core->pp);
110 }
111 if (one_socket_per_cpu)
112 socket = socket->next;
113 }
114 return socket;
115 }
116
clear_masks(void)117 static void clear_masks(void)
118 {
119 struct mask_info *info;
120
121 info = &socket_info;
122 while (info) {
123 cpumask_clear(&info->mask);
124 info = info->next;
125 }
126 info = &book_info;
127 while (info) {
128 cpumask_clear(&info->mask);
129 info = info->next;
130 }
131 }
132
next_tle(union topology_entry * tle)133 static union topology_entry *next_tle(union topology_entry *tle)
134 {
135 if (!tle->nl)
136 return (union topology_entry *)((struct topology_core *)tle + 1);
137 return (union topology_entry *)((struct topology_container *)tle + 1);
138 }
139
__tl_to_masks_generic(struct sysinfo_15_1_x * info)140 static void __tl_to_masks_generic(struct sysinfo_15_1_x *info)
141 {
142 struct mask_info *socket = &socket_info;
143 struct mask_info *book = &book_info;
144 union topology_entry *tle, *end;
145
146 tle = info->tle;
147 end = (union topology_entry *)((unsigned long)info + info->length);
148 while (tle < end) {
149 switch (tle->nl) {
150 case 2:
151 book = book->next;
152 book->id = tle->container.id;
153 break;
154 case 1:
155 socket = socket->next;
156 socket->id = tle->container.id;
157 break;
158 case 0:
159 add_cpus_to_mask(&tle->cpu, book, socket, 0);
160 break;
161 default:
162 clear_masks();
163 return;
164 }
165 tle = next_tle(tle);
166 }
167 }
168
__tl_to_masks_z10(struct sysinfo_15_1_x * info)169 static void __tl_to_masks_z10(struct sysinfo_15_1_x *info)
170 {
171 struct mask_info *socket = &socket_info;
172 struct mask_info *book = &book_info;
173 union topology_entry *tle, *end;
174
175 tle = info->tle;
176 end = (union topology_entry *)((unsigned long)info + info->length);
177 while (tle < end) {
178 switch (tle->nl) {
179 case 1:
180 book = book->next;
181 book->id = tle->container.id;
182 break;
183 case 0:
184 socket = add_cpus_to_mask(&tle->cpu, book, socket, 1);
185 break;
186 default:
187 clear_masks();
188 return;
189 }
190 tle = next_tle(tle);
191 }
192 }
193
tl_to_masks(struct sysinfo_15_1_x * info)194 static void tl_to_masks(struct sysinfo_15_1_x *info)
195 {
196 struct cpuid cpu_id;
197
198 get_cpu_id(&cpu_id);
199 clear_masks();
200 switch (cpu_id.machine) {
201 case 0x2097:
202 case 0x2098:
203 __tl_to_masks_z10(info);
204 break;
205 default:
206 __tl_to_masks_generic(info);
207 }
208 }
209
topology_update_polarization_simple(void)210 static void topology_update_polarization_simple(void)
211 {
212 int cpu;
213
214 mutex_lock(&smp_cpu_state_mutex);
215 for_each_possible_cpu(cpu)
216 smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
217 mutex_unlock(&smp_cpu_state_mutex);
218 }
219
ptf(unsigned long fc)220 static int ptf(unsigned long fc)
221 {
222 int rc;
223
224 asm volatile(
225 " .insn rre,0xb9a20000,%1,%1\n"
226 " ipm %0\n"
227 " srl %0,28\n"
228 : "=d" (rc)
229 : "d" (fc) : "cc");
230 return rc;
231 }
232
topology_set_cpu_management(int fc)233 int topology_set_cpu_management(int fc)
234 {
235 int cpu, rc;
236
237 if (!MACHINE_HAS_TOPOLOGY)
238 return -EOPNOTSUPP;
239 if (fc)
240 rc = ptf(PTF_VERTICAL);
241 else
242 rc = ptf(PTF_HORIZONTAL);
243 if (rc)
244 return -EBUSY;
245 for_each_possible_cpu(cpu)
246 smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
247 return rc;
248 }
249
update_cpu_masks(void)250 static void update_cpu_masks(void)
251 {
252 struct cpu_topology_s390 *topo;
253 int cpu;
254
255 for_each_possible_cpu(cpu) {
256 topo = &per_cpu(cpu_topology, cpu);
257 topo->thread_mask = cpu_thread_map(cpu);
258 topo->core_mask = cpu_group_map(&socket_info, cpu);
259 topo->book_mask = cpu_group_map(&book_info, cpu);
260 if (!MACHINE_HAS_TOPOLOGY) {
261 topo->thread_id = cpu;
262 topo->core_id = cpu;
263 topo->socket_id = cpu;
264 topo->book_id = cpu;
265 }
266 }
267 numa_update_cpu_topology();
268 }
269
store_topology(struct sysinfo_15_1_x * info)270 void store_topology(struct sysinfo_15_1_x *info)
271 {
272 if (topology_max_mnest >= 3)
273 stsi(info, 15, 1, 3);
274 else
275 stsi(info, 15, 1, 2);
276 }
277
arch_update_cpu_topology(void)278 int arch_update_cpu_topology(void)
279 {
280 struct sysinfo_15_1_x *info = tl_info;
281 struct device *dev;
282 int cpu, rc = 0;
283
284 if (MACHINE_HAS_TOPOLOGY) {
285 rc = 1;
286 store_topology(info);
287 tl_to_masks(info);
288 }
289 update_cpu_masks();
290 if (!MACHINE_HAS_TOPOLOGY)
291 topology_update_polarization_simple();
292 for_each_online_cpu(cpu) {
293 dev = get_cpu_device(cpu);
294 if (dev)
295 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
296 }
297 return rc;
298 }
299
topology_work_fn(struct work_struct * work)300 static void topology_work_fn(struct work_struct *work)
301 {
302 rebuild_sched_domains();
303 }
304
topology_schedule_update(void)305 void topology_schedule_update(void)
306 {
307 schedule_work(&topology_work);
308 }
309
topology_timer_fn(unsigned long ignored)310 static void topology_timer_fn(unsigned long ignored)
311 {
312 if (ptf(PTF_CHECK))
313 topology_schedule_update();
314 set_topology_timer();
315 }
316
317 static struct timer_list topology_timer =
318 TIMER_DEFERRED_INITIALIZER(topology_timer_fn, 0, 0);
319
320 static atomic_t topology_poll = ATOMIC_INIT(0);
321
set_topology_timer(void)322 static void set_topology_timer(void)
323 {
324 if (atomic_add_unless(&topology_poll, -1, 0))
325 mod_timer(&topology_timer, jiffies + HZ / 10);
326 else
327 mod_timer(&topology_timer, jiffies + HZ * 60);
328 }
329
topology_expect_change(void)330 void topology_expect_change(void)
331 {
332 if (!MACHINE_HAS_TOPOLOGY)
333 return;
334 /* This is racy, but it doesn't matter since it is just a heuristic.
335 * Worst case is that we poll in a higher frequency for a bit longer.
336 */
337 if (atomic_read(&topology_poll) > 60)
338 return;
339 atomic_add(60, &topology_poll);
340 set_topology_timer();
341 }
342
343 static int cpu_management;
344
dispatching_show(struct device * dev,struct device_attribute * attr,char * buf)345 static ssize_t dispatching_show(struct device *dev,
346 struct device_attribute *attr,
347 char *buf)
348 {
349 ssize_t count;
350
351 mutex_lock(&smp_cpu_state_mutex);
352 count = sprintf(buf, "%d\n", cpu_management);
353 mutex_unlock(&smp_cpu_state_mutex);
354 return count;
355 }
356
dispatching_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)357 static ssize_t dispatching_store(struct device *dev,
358 struct device_attribute *attr,
359 const char *buf,
360 size_t count)
361 {
362 int val, rc;
363 char delim;
364
365 if (sscanf(buf, "%d %c", &val, &delim) != 1)
366 return -EINVAL;
367 if (val != 0 && val != 1)
368 return -EINVAL;
369 rc = 0;
370 get_online_cpus();
371 mutex_lock(&smp_cpu_state_mutex);
372 if (cpu_management == val)
373 goto out;
374 rc = topology_set_cpu_management(val);
375 if (rc)
376 goto out;
377 cpu_management = val;
378 topology_expect_change();
379 out:
380 mutex_unlock(&smp_cpu_state_mutex);
381 put_online_cpus();
382 return rc ? rc : count;
383 }
384 static DEVICE_ATTR(dispatching, 0644, dispatching_show,
385 dispatching_store);
386
cpu_polarization_show(struct device * dev,struct device_attribute * attr,char * buf)387 static ssize_t cpu_polarization_show(struct device *dev,
388 struct device_attribute *attr, char *buf)
389 {
390 int cpu = dev->id;
391 ssize_t count;
392
393 mutex_lock(&smp_cpu_state_mutex);
394 switch (smp_cpu_get_polarization(cpu)) {
395 case POLARIZATION_HRZ:
396 count = sprintf(buf, "horizontal\n");
397 break;
398 case POLARIZATION_VL:
399 count = sprintf(buf, "vertical:low\n");
400 break;
401 case POLARIZATION_VM:
402 count = sprintf(buf, "vertical:medium\n");
403 break;
404 case POLARIZATION_VH:
405 count = sprintf(buf, "vertical:high\n");
406 break;
407 default:
408 count = sprintf(buf, "unknown\n");
409 break;
410 }
411 mutex_unlock(&smp_cpu_state_mutex);
412 return count;
413 }
414 static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);
415
416 static struct attribute *topology_cpu_attrs[] = {
417 &dev_attr_polarization.attr,
418 NULL,
419 };
420
421 static struct attribute_group topology_cpu_attr_group = {
422 .attrs = topology_cpu_attrs,
423 };
424
topology_cpu_init(struct cpu * cpu)425 int topology_cpu_init(struct cpu *cpu)
426 {
427 return sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
428 }
429
cpu_thread_mask(int cpu)430 static const struct cpumask *cpu_thread_mask(int cpu)
431 {
432 return &per_cpu(cpu_topology, cpu).thread_mask;
433 }
434
435
cpu_coregroup_mask(int cpu)436 const struct cpumask *cpu_coregroup_mask(int cpu)
437 {
438 return &per_cpu(cpu_topology, cpu).core_mask;
439 }
440
cpu_book_mask(int cpu)441 static const struct cpumask *cpu_book_mask(int cpu)
442 {
443 return &per_cpu(cpu_topology, cpu).book_mask;
444 }
445
early_parse_topology(char * p)446 static int __init early_parse_topology(char *p)
447 {
448 if (strncmp(p, "off", 3))
449 return 0;
450 topology_enabled = 0;
451 return 0;
452 }
453 early_param("topology", early_parse_topology);
454
455 static struct sched_domain_topology_level s390_topology[] = {
456 { cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
457 { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
458 { cpu_book_mask, SD_INIT_NAME(BOOK) },
459 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
460 { NULL, },
461 };
462
alloc_masks(struct sysinfo_15_1_x * info,struct mask_info * mask,int offset)463 static void __init alloc_masks(struct sysinfo_15_1_x *info,
464 struct mask_info *mask, int offset)
465 {
466 int i, nr_masks;
467
468 nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
469 for (i = 0; i < info->mnest - offset; i++)
470 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
471 nr_masks = max(nr_masks, 1);
472 for (i = 0; i < nr_masks; i++) {
473 mask->next = kzalloc(sizeof(*mask->next), GFP_KERNEL);
474 mask = mask->next;
475 }
476 }
477
s390_topology_init(void)478 static int __init s390_topology_init(void)
479 {
480 struct sysinfo_15_1_x *info;
481 int i;
482
483 if (!MACHINE_HAS_TOPOLOGY)
484 return 0;
485 tl_info = (struct sysinfo_15_1_x *)__get_free_page(GFP_KERNEL);
486 info = tl_info;
487 store_topology(info);
488 pr_info("The CPU configuration topology of the machine is:");
489 for (i = 0; i < TOPOLOGY_NR_MAG; i++)
490 printk(KERN_CONT " %d", info->mag[i]);
491 printk(KERN_CONT " / %d\n", info->mnest);
492 alloc_masks(info, &socket_info, 1);
493 alloc_masks(info, &book_info, 2);
494 set_sched_topology(s390_topology);
495 return 0;
496 }
497 early_initcall(s390_topology_init);
498
topology_init(void)499 static int __init topology_init(void)
500 {
501 if (MACHINE_HAS_TOPOLOGY)
502 set_topology_timer();
503 else
504 topology_update_polarization_simple();
505 return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
506 }
507 device_initcall(topology_init);
508