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[~shefty/rdma-dev.git] / arch / s390 / kernel / topology.c
1 /*
2  *    Copyright IBM Corp. 2007
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/kernel.h>
10 #include <linux/mm.h>
11 #include <linux/init.h>
12 #include <linux/device.h>
13 #include <linux/bootmem.h>
14 #include <linux/sched.h>
15 #include <linux/workqueue.h>
16 #include <linux/cpu.h>
17 #include <linux/smp.h>
18 #include <linux/cpuset.h>
19 #include <asm/delay.h>
20 #include <asm/s390_ext.h>
21 #include <asm/sysinfo.h>
22
23 #define PTF_HORIZONTAL  (0UL)
24 #define PTF_VERTICAL    (1UL)
25 #define PTF_CHECK       (2UL)
26
27 struct mask_info {
28         struct mask_info *next;
29         unsigned char id;
30         cpumask_t mask;
31 };
32
33 static int topology_enabled = 1;
34 static void topology_work_fn(struct work_struct *work);
35 static struct sysinfo_15_1_x *tl_info;
36 static struct timer_list topology_timer;
37 static void set_topology_timer(void);
38 static DECLARE_WORK(topology_work, topology_work_fn);
39 /* topology_lock protects the core linked list */
40 static DEFINE_SPINLOCK(topology_lock);
41
42 static struct mask_info core_info;
43 cpumask_t cpu_core_map[NR_CPUS];
44 unsigned char cpu_core_id[NR_CPUS];
45
46 #ifdef CONFIG_SCHED_BOOK
47 static struct mask_info book_info;
48 cpumask_t cpu_book_map[NR_CPUS];
49 unsigned char cpu_book_id[NR_CPUS];
50 #endif
51
52 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
53 {
54         cpumask_t mask;
55
56         cpus_clear(mask);
57         if (!topology_enabled || !MACHINE_HAS_TOPOLOGY)
58                 return cpu_possible_map;
59         while (info) {
60                 if (cpu_isset(cpu, info->mask)) {
61                         mask = info->mask;
62                         break;
63                 }
64                 info = info->next;
65         }
66         if (cpus_empty(mask))
67                 mask = cpumask_of_cpu(cpu);
68         return mask;
69 }
70
71 static void add_cpus_to_mask(struct topology_cpu *tl_cpu,
72                              struct mask_info *book, struct mask_info *core)
73 {
74         unsigned int cpu;
75
76         for (cpu = find_first_bit(&tl_cpu->mask[0], TOPOLOGY_CPU_BITS);
77              cpu < TOPOLOGY_CPU_BITS;
78              cpu = find_next_bit(&tl_cpu->mask[0], TOPOLOGY_CPU_BITS, cpu + 1))
79         {
80                 unsigned int rcpu, lcpu;
81
82                 rcpu = TOPOLOGY_CPU_BITS - 1 - cpu + tl_cpu->origin;
83                 for_each_present_cpu(lcpu) {
84                         if (cpu_logical_map(lcpu) != rcpu)
85                                 continue;
86 #ifdef CONFIG_SCHED_BOOK
87                         cpu_set(lcpu, book->mask);
88                         cpu_book_id[lcpu] = book->id;
89 #endif
90                         cpu_set(lcpu, core->mask);
91                         cpu_core_id[lcpu] = core->id;
92                         smp_cpu_polarization[lcpu] = tl_cpu->pp;
93                 }
94         }
95 }
96
97 static void clear_masks(void)
98 {
99         struct mask_info *info;
100
101         info = &core_info;
102         while (info) {
103                 cpus_clear(info->mask);
104                 info = info->next;
105         }
106 #ifdef CONFIG_SCHED_BOOK
107         info = &book_info;
108         while (info) {
109                 cpus_clear(info->mask);
110                 info = info->next;
111         }
112 #endif
113 }
114
115 static union topology_entry *next_tle(union topology_entry *tle)
116 {
117         if (!tle->nl)
118                 return (union topology_entry *)((struct topology_cpu *)tle + 1);
119         return (union topology_entry *)((struct topology_container *)tle + 1);
120 }
121
122 static void tl_to_cores(struct sysinfo_15_1_x *info)
123 {
124 #ifdef CONFIG_SCHED_BOOK
125         struct mask_info *book = &book_info;
126 #else
127         struct mask_info *book = NULL;
128 #endif
129         struct mask_info *core = &core_info;
130         union topology_entry *tle, *end;
131
132
133         spin_lock_irq(&topology_lock);
134         clear_masks();
135         tle = info->tle;
136         end = (union topology_entry *)((unsigned long)info + info->length);
137         while (tle < end) {
138                 switch (tle->nl) {
139 #ifdef CONFIG_SCHED_BOOK
140                 case 2:
141                         book = book->next;
142                         book->id = tle->container.id;
143                         break;
144 #endif
145                 case 1:
146                         core = core->next;
147                         core->id = tle->container.id;
148                         break;
149                 case 0:
150                         add_cpus_to_mask(&tle->cpu, book, core);
151                         break;
152                 default:
153                         clear_masks();
154                         goto out;
155                 }
156                 tle = next_tle(tle);
157         }
158 out:
159         spin_unlock_irq(&topology_lock);
160 }
161
162 static void topology_update_polarization_simple(void)
163 {
164         int cpu;
165
166         mutex_lock(&smp_cpu_state_mutex);
167         for_each_possible_cpu(cpu)
168                 smp_cpu_polarization[cpu] = POLARIZATION_HRZ;
169         mutex_unlock(&smp_cpu_state_mutex);
170 }
171
172 static int ptf(unsigned long fc)
173 {
174         int rc;
175
176         asm volatile(
177                 "       .insn   rre,0xb9a20000,%1,%1\n"
178                 "       ipm     %0\n"
179                 "       srl     %0,28\n"
180                 : "=d" (rc)
181                 : "d" (fc)  : "cc");
182         return rc;
183 }
184
185 int topology_set_cpu_management(int fc)
186 {
187         int cpu;
188         int rc;
189
190         if (!MACHINE_HAS_TOPOLOGY)
191                 return -EOPNOTSUPP;
192         if (fc)
193                 rc = ptf(PTF_VERTICAL);
194         else
195                 rc = ptf(PTF_HORIZONTAL);
196         if (rc)
197                 return -EBUSY;
198         for_each_possible_cpu(cpu)
199                 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
200         return rc;
201 }
202
203 static void update_cpu_core_map(void)
204 {
205         unsigned long flags;
206         int cpu;
207
208         spin_lock_irqsave(&topology_lock, flags);
209         for_each_possible_cpu(cpu) {
210                 cpu_core_map[cpu] = cpu_group_map(&core_info, cpu);
211 #ifdef CONFIG_SCHED_BOOK
212                 cpu_book_map[cpu] = cpu_group_map(&book_info, cpu);
213 #endif
214         }
215         spin_unlock_irqrestore(&topology_lock, flags);
216 }
217
218 static void store_topology(struct tl_info *info)
219 {
220 #ifdef CONFIG_SCHED_BOOK
221         int rc;
222
223         rc = stsi(info, 15, 1, 3);
224         if (rc != -ENOSYS)
225                 return;
226 #endif
227         stsi(info, 15, 1, 2);
228 }
229
230 int arch_update_cpu_topology(void)
231 {
232         struct sysinfo_15_1_x *info = tl_info;
233         struct sys_device *sysdev;
234         int cpu;
235
236         if (!MACHINE_HAS_TOPOLOGY) {
237                 update_cpu_core_map();
238                 topology_update_polarization_simple();
239                 return 0;
240         }
241         store_topology(info);
242         tl_to_cores(info);
243         update_cpu_core_map();
244         for_each_online_cpu(cpu) {
245                 sysdev = get_cpu_sysdev(cpu);
246                 kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
247         }
248         return 1;
249 }
250
251 static void topology_work_fn(struct work_struct *work)
252 {
253         rebuild_sched_domains();
254 }
255
256 void topology_schedule_update(void)
257 {
258         schedule_work(&topology_work);
259 }
260
261 static void topology_timer_fn(unsigned long ignored)
262 {
263         if (ptf(PTF_CHECK))
264                 topology_schedule_update();
265         set_topology_timer();
266 }
267
268 static void set_topology_timer(void)
269 {
270         topology_timer.function = topology_timer_fn;
271         topology_timer.data = 0;
272         topology_timer.expires = jiffies + 60 * HZ;
273         add_timer(&topology_timer);
274 }
275
276 static int __init early_parse_topology(char *p)
277 {
278         if (strncmp(p, "off", 3))
279                 return 0;
280         topology_enabled = 0;
281         return 0;
282 }
283 early_param("topology", early_parse_topology);
284
285 static int __init init_topology_update(void)
286 {
287         int rc;
288
289         rc = 0;
290         if (!MACHINE_HAS_TOPOLOGY) {
291                 topology_update_polarization_simple();
292                 goto out;
293         }
294         init_timer_deferrable(&topology_timer);
295         set_topology_timer();
296 out:
297         update_cpu_core_map();
298         return rc;
299 }
300 __initcall(init_topology_update);
301
302 static void alloc_masks(struct sysinfo_15_1_x *info, struct mask_info *mask,
303                         int offset)
304 {
305         int i, nr_masks;
306
307         nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
308         for (i = 0; i < info->mnest - offset; i++)
309                 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
310         nr_masks = max(nr_masks, 1);
311         for (i = 0; i < nr_masks; i++) {
312                 mask->next = alloc_bootmem(sizeof(struct mask_info));
313                 mask = mask->next;
314         }
315 }
316
317 void __init s390_init_cpu_topology(void)
318 {
319         struct sysinfo_15_1_x *info;
320         int i;
321
322         if (!MACHINE_HAS_TOPOLOGY)
323                 return;
324         tl_info = alloc_bootmem_pages(PAGE_SIZE);
325         info = tl_info;
326         store_topology(info);
327         pr_info("The CPU configuration topology of the machine is:");
328         for (i = 0; i < TOPOLOGY_NR_MAG; i++)
329                 printk(" %d", info->mag[i]);
330         printk(" / %d\n", info->mnest);
331         alloc_masks(info, &core_info, 2);
332 #ifdef CONFIG_SCHED_BOOK
333         alloc_masks(info, &book_info, 3);
334 #endif
335 }