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
  21 #define PTF_HORIZONTAL  (0UL)
  22 #define PTF_VERTICAL    (1UL)
  23 #define PTF_CHECK       (2UL)
  24
  25 struct mask_info {
  26         struct mask_info *next;
  27         unsigned char id;
  28         cpumask_t mask;
  29 };
  30
  31 static int topology_enabled = 1;
  32 static void topology_work_fn(struct work_struct *work);
  33 static struct sysinfo_15_1_x *tl_info;
  34 static struct timer_list topology_timer;
  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);
  39
  40 static struct mask_info core_info;
  41 cpumask_t cpu_core_map[NR_CPUS];
  42 unsigned char cpu_core_id[NR_CPUS];
  43
  44 #ifdef CONFIG_SCHED_BOOK
  45 static struct mask_info book_info;
  46 cpumask_t cpu_book_map[NR_CPUS];
  47 unsigned char cpu_book_id[NR_CPUS];
  48 #endif
  49
  50 static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
  51 {
  52         cpumask_t mask;
  53
  54         cpumask_clear(&mask);
  55         if (!topology_enabled || !MACHINE_HAS_TOPOLOGY) {
  56                 cpumask_copy(&mask, cpumask_of(cpu));
  57                 return mask;
  58         }
  59         while (info) {
  60                 if (cpumask_test_cpu(cpu, &info->mask)) {
  61                         mask = info->mask;
  62                         break;
  63                 }
  64                 info = info->next;
  65         }
  66         if (cpumask_empty(&mask))
  67                 cpumask_copy(&mask, cpumask_of(cpu));
  68         return mask;
  69 }
  70
  71 static struct mask_info *add_cpus_to_mask(struct topology_cpu *tl_cpu,
  72                                           struct mask_info *book,
  73                                           struct mask_info *core,
  74                                           int z10)
  75 {
  76         unsigned int cpu;
  77
  78         for (cpu = find_first_bit(&tl_cpu->mask[0], TOPOLOGY_CPU_BITS);
  79              cpu < TOPOLOGY_CPU_BITS;
  80              cpu = find_next_bit(&tl_cpu->mask[0], TOPOLOGY_CPU_BITS, cpu + 1))
  81         {
  82                 unsigned int rcpu, lcpu;
  83
  84                 rcpu = TOPOLOGY_CPU_BITS - 1 - cpu + tl_cpu->origin;
  85                 for_each_present_cpu(lcpu) {
  86                         if (cpu_logical_map(lcpu) != rcpu)
  87                                 continue;
  88 #ifdef CONFIG_SCHED_BOOK
  89                         cpumask_set_cpu(lcpu, &book->mask);
  90                         cpu_book_id[lcpu] = book->id;
  91 #endif
  92                         cpumask_set_cpu(lcpu, &core->mask);
  93                         if (z10) {
  94                                 cpu_core_id[lcpu] = rcpu;
  95                                 core = core->next;
  96                         } else {
  97                                 cpu_core_id[lcpu] = core->id;
  98                         }
  99                         smp_cpu_polarization[lcpu] = tl_cpu->pp;
 100                 }
 101         }
 102         return core;
 103 }
 104
 105 static void clear_masks(void)
 106 {
 107         struct mask_info *info;
 108
 109         info = &core_info;
 110         while (info) {
 111                 cpumask_clear(&info->mask);
 112                 info = info->next;
 113         }
 114 #ifdef CONFIG_SCHED_BOOK
 115         info = &book_info;
 116         while (info) {
 117                 cpumask_clear(&info->mask);
 118                 info = info->next;
 119         }
 120 #endif
 121 }
 122
 123 static union topology_entry *next_tle(union topology_entry *tle)
 124 {
 125         if (!tle->nl)
 126                 return (union topology_entry *)((struct topology_cpu *)tle + 1);
 127         return (union topology_entry *)((struct topology_container *)tle + 1);
 128 }
 129
 130 static void tl_to_cores(struct sysinfo_15_1_x *info)
 131 {
 132 #ifdef CONFIG_SCHED_BOOK
 133         struct mask_info *book = &book_info;
 134         struct cpuid cpu_id;
 135 #else
 136         struct mask_info *book = NULL;
 137 #endif
 138         struct mask_info *core = &core_info;
 139         union topology_entry *tle, *end;
 140         int z10 = 0;
 141
 142 #ifdef CONFIG_SCHED_BOOK
 143         get_cpu_id(&cpu_id);
 144         z10 = cpu_id.machine == 0x2097 || cpu_id.machine == 0x2098;
 145 #endif
 146         spin_lock_irq(&topology_lock);
 147         clear_masks();
 148         tle = info->tle;
 149         end = (union topology_entry *)((unsigned long)info + info->length);
 150         while (tle < end) {
 151 #ifdef CONFIG_SCHED_BOOK
 152                 if (z10) {
 153                         switch (tle->nl) {
 154                         case 1:
 155                                 book = book->next;
 156                                 book->id = tle->container.id;
 157                                 break;
 158                         case 0:
 159                                 core = add_cpus_to_mask(&tle->cpu, book, core, z10);
 160                                 break;
 161                         default:
 162                                 clear_masks();
 163                                 goto out;
 164                         }
 165                         tle = next_tle(tle);
 166                         continue;
 167                 }
 168 #endif
 169                 switch (tle->nl) {
 170 #ifdef CONFIG_SCHED_BOOK
 171                 case 2:
 172                         book = book->next;
 173                         book->id = tle->container.id;
 174                         break;
 175 #endif
 176                 case 1:
 177                         core = core->next;
 178                         core->id = tle->container.id;
 179                         break;
 180                 case 0:
 181                         add_cpus_to_mask(&tle->cpu, book, core, z10);
 182                         break;
 183                 default:
 184                         clear_masks();
 185                         goto out;
 186                 }
 187                 tle = next_tle(tle);
 188         }
 189 out:
 190         spin_unlock_irq(&topology_lock);
 191 }
 192
 193 static void topology_update_polarization_simple(void)
 194 {
 195         int cpu;
 196
 197         mutex_lock(&smp_cpu_state_mutex);
 198         for_each_possible_cpu(cpu)
 199                 smp_cpu_polarization[cpu] = POLARIZATION_HRZ;
 200         mutex_unlock(&smp_cpu_state_mutex);
 201 }
 202
 203 static int ptf(unsigned long fc)
 204 {
 205         int rc;
 206
 207         asm volatile(
 208                 "       .insn   rre,0xb9a20000,%1,%1\n"
 209                 "       ipm     %0\n"
 210                 "       srl     %0,28\n"
 211                 : "=d" (rc)
 212                 : "d" (fc)  : "cc");
 213         return rc;
 214 }
 215
 216 int topology_set_cpu_management(int fc)
 217 {
 218         int cpu;
 219         int rc;
 220
 221         if (!MACHINE_HAS_TOPOLOGY)
 222                 return -EOPNOTSUPP;
 223         if (fc)
 224                 rc = ptf(PTF_VERTICAL);
 225         else
 226                 rc = ptf(PTF_HORIZONTAL);
 227         if (rc)
 228                 return -EBUSY;
 229         for_each_possible_cpu(cpu)
 230                 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
 231         return rc;
 232 }
 233
 234 static void update_cpu_core_map(void)
 235 {
 236         unsigned long flags;
 237         int cpu;
 238
 239         spin_lock_irqsave(&topology_lock, flags);
 240         for_each_possible_cpu(cpu) {
 241                 cpu_core_map[cpu] = cpu_group_map(&core_info, cpu);
 242 #ifdef CONFIG_SCHED_BOOK
 243                 cpu_book_map[cpu] = cpu_group_map(&book_info, cpu);
 244 #endif
 245         }
 246         spin_unlock_irqrestore(&topology_lock, flags);
 247 }
 248
 249 void store_topology(struct sysinfo_15_1_x *info)
 250 {
 251 #ifdef CONFIG_SCHED_BOOK
 252         int rc;
 253
 254         rc = stsi(info, 15, 1, 3);
 255         if (rc != -ENOSYS)
 256                 return;
 257 #endif
 258         stsi(info, 15, 1, 2);
 259 }
 260
 261 int arch_update_cpu_topology(void)
 262 {
 263         struct sysinfo_15_1_x *info = tl_info;
 264         struct sys_device *sysdev;
 265         int cpu;
 266
 267         if (!MACHINE_HAS_TOPOLOGY) {
 268                 update_cpu_core_map();
 269                 topology_update_polarization_simple();
 270                 return 0;
 271         }
 272         store_topology(info);
 273         tl_to_cores(info);
 274         update_cpu_core_map();
 275         for_each_online_cpu(cpu) {
 276                 sysdev = get_cpu_sysdev(cpu);
 277                 kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
 278         }
 279         return 1;
 280 }
 281
 282 static void topology_work_fn(struct work_struct *work)
 283 {
 284         rebuild_sched_domains();
 285 }
 286
 287 void topology_schedule_update(void)
 288 {
 289         schedule_work(&topology_work);
 290 }
 291
 292 static void topology_timer_fn(unsigned long ignored)
 293 {
 294         if (ptf(PTF_CHECK))
 295                 topology_schedule_update();
 296         set_topology_timer();
 297 }
 298
 299 static void set_topology_timer(void)
 300 {
 301         topology_timer.function = topology_timer_fn;
 302         topology_timer.data = 0;
 303         topology_timer.expires = jiffies + 60 * HZ;
 304         add_timer(&topology_timer);
 305 }
 306
 307 static int __init early_parse_topology(char *p)
 308 {
 309         if (strncmp(p, "off", 3))
 310                 return 0;
 311         topology_enabled = 0;
 312         return 0;
 313 }
 314 early_param("topology", early_parse_topology);
 315
 316 static int __init init_topology_update(void)
 317 {
 318         int rc;
 319
 320         rc = 0;
 321         if (!MACHINE_HAS_TOPOLOGY) {
 322                 topology_update_polarization_simple();
 323                 goto out;
 324         }
 325         init_timer_deferrable(&topology_timer);
 326         set_topology_timer();
 327 out:
 328         update_cpu_core_map();
 329         return rc;
 330 }
 331 __initcall(init_topology_update);
 332
 333 static void __init alloc_masks(struct sysinfo_15_1_x *info,
 334                                struct mask_info *mask, int offset)
 335 {
 336         int i, nr_masks;
 337
 338         nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
 339         for (i = 0; i < info->mnest - offset; i++)
 340                 nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
 341         nr_masks = max(nr_masks, 1);
 342         for (i = 0; i < nr_masks; i++) {
 343                 mask->next = alloc_bootmem(sizeof(struct mask_info));
 344                 mask = mask->next;
 345         }
 346 }
 347
 348 void __init s390_init_cpu_topology(void)
 349 {
 350         struct sysinfo_15_1_x *info;
 351         int i;
 352
 353         if (!MACHINE_HAS_TOPOLOGY)
 354                 return;
 355         tl_info = alloc_bootmem_pages(PAGE_SIZE);
 356         info = tl_info;
 357         store_topology(info);
 358         pr_info("The CPU configuration topology of the machine is:");
 359         for (i = 0; i < TOPOLOGY_NR_MAG; i++)
 360                 printk(" %d", info->mag[i]);
 361         printk(" / %d\n", info->mnest);
 362         alloc_masks(info, &core_info, 1);
 363 #ifdef CONFIG_SCHED_BOOK
 364         alloc_masks(info, &book_info, 2);
 365 #endif
 366 }