arch/i386/kernel/cpu/intel_cacheinfo.c

   1 /*
   2  *      Routines to indentify caches on Intel CPU.
   3  *
   4  *      Changes:
   5  *      Venkatesh Pallipadi     : Adding cache identification through cpuid(4)
   6  *              Ashok Raj <ashok.raj@intel.com>: Work with CPU hotplug infrastructure.
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/device.h>
  12 #include <linux/compiler.h>
  13 #include <linux/cpu.h>
  14 #include <linux/sched.h>
  15
  16 #include <asm/processor.h>
  17 #include <asm/smp.h>
  18
  19 #define LVL_1_INST      1
  20 #define LVL_1_DATA      2
  21 #define LVL_2           3
  22 #define LVL_3           4
  23 #define LVL_TRACE       5
  24
  25 struct _cache_table
  26 {
  27         unsigned char descriptor;
  28         char cache_type;
  29         short size;
  30 };
  31
  32 /* all the cache descriptor types we care about (no TLB or trace cache entries) */
  33 static struct _cache_table cache_table[] __cpuinitdata =
  34 {
  35         { 0x06, LVL_1_INST, 8 },        /* 4-way set assoc, 32 byte line size */
  36         { 0x08, LVL_1_INST, 16 },       /* 4-way set assoc, 32 byte line size */
  37         { 0x0a, LVL_1_DATA, 8 },        /* 2 way set assoc, 32 byte line size */
  38         { 0x0c, LVL_1_DATA, 16 },       /* 4-way set assoc, 32 byte line size */
  39         { 0x22, LVL_3,      512 },      /* 4-way set assoc, sectored cache, 64 byte line size */
  40         { 0x23, LVL_3,      1024 },     /* 8-way set assoc, sectored cache, 64 byte line size */
  41         { 0x25, LVL_3,      2048 },     /* 8-way set assoc, sectored cache, 64 byte line size */
  42         { 0x29, LVL_3,      4096 },     /* 8-way set assoc, sectored cache, 64 byte line size */
  43         { 0x2c, LVL_1_DATA, 32 },       /* 8-way set assoc, 64 byte line size */
  44         { 0x30, LVL_1_INST, 32 },       /* 8-way set assoc, 64 byte line size */
  45         { 0x39, LVL_2,      128 },      /* 4-way set assoc, sectored cache, 64 byte line size */
  46         { 0x3b, LVL_2,      128 },      /* 2-way set assoc, sectored cache, 64 byte line size */
  47         { 0x3c, LVL_2,      256 },      /* 4-way set assoc, sectored cache, 64 byte line size */
  48         { 0x41, LVL_2,      128 },      /* 4-way set assoc, 32 byte line size */
  49         { 0x42, LVL_2,      256 },      /* 4-way set assoc, 32 byte line size */
  50         { 0x43, LVL_2,      512 },      /* 4-way set assoc, 32 byte line size */
  51         { 0x44, LVL_2,      1024 },     /* 4-way set assoc, 32 byte line size */
  52         { 0x45, LVL_2,      2048 },     /* 4-way set assoc, 32 byte line size */
  53         { 0x60, LVL_1_DATA, 16 },       /* 8-way set assoc, sectored cache, 64 byte line size */
  54         { 0x66, LVL_1_DATA, 8 },        /* 4-way set assoc, sectored cache, 64 byte line size */
  55         { 0x67, LVL_1_DATA, 16 },       /* 4-way set assoc, sectored cache, 64 byte line size */
  56         { 0x68, LVL_1_DATA, 32 },       /* 4-way set assoc, sectored cache, 64 byte line size */
  57         { 0x70, LVL_TRACE,  12 },       /* 8-way set assoc */
  58         { 0x71, LVL_TRACE,  16 },       /* 8-way set assoc */
  59         { 0x72, LVL_TRACE,  32 },       /* 8-way set assoc */
  60         { 0x78, LVL_2,    1024 },       /* 4-way set assoc, 64 byte line size */
  61         { 0x79, LVL_2,     128 },       /* 8-way set assoc, sectored cache, 64 byte line size */
  62         { 0x7a, LVL_2,     256 },       /* 8-way set assoc, sectored cache, 64 byte line size */
  63         { 0x7b, LVL_2,     512 },       /* 8-way set assoc, sectored cache, 64 byte line size */
  64         { 0x7c, LVL_2,    1024 },       /* 8-way set assoc, sectored cache, 64 byte line size */
  65         { 0x7d, LVL_2,    2048 },       /* 8-way set assoc, 64 byte line size */
  66         { 0x7f, LVL_2,     512 },       /* 2-way set assoc, 64 byte line size */
  67         { 0x82, LVL_2,     256 },       /* 8-way set assoc, 32 byte line size */
  68         { 0x83, LVL_2,     512 },       /* 8-way set assoc, 32 byte line size */
  69         { 0x84, LVL_2,    1024 },       /* 8-way set assoc, 32 byte line size */
  70         { 0x85, LVL_2,    2048 },       /* 8-way set assoc, 32 byte line size */
  71         { 0x86, LVL_2,     512 },       /* 4-way set assoc, 64 byte line size */
  72         { 0x87, LVL_2,    1024 },       /* 8-way set assoc, 64 byte line size */
  73         { 0x00, 0, 0}
  74 };
  75
  76
  77 enum _cache_type
  78 {
  79         CACHE_TYPE_NULL = 0,
  80         CACHE_TYPE_DATA = 1,
  81         CACHE_TYPE_INST = 2,
  82         CACHE_TYPE_UNIFIED = 3
  83 };
  84
  85 union _cpuid4_leaf_eax {
  86         struct {
  87                 enum _cache_type        type:5;
  88                 unsigned int            level:3;
  89                 unsigned int            is_self_initializing:1;
  90                 unsigned int            is_fully_associative:1;
  91                 unsigned int            reserved:4;
  92                 unsigned int            num_threads_sharing:12;
  93                 unsigned int            num_cores_on_die:6;
  94         } split;
  95         u32 full;
  96 };
  97
  98 union _cpuid4_leaf_ebx {
  99         struct {
 100                 unsigned int            coherency_line_size:12;
 101                 unsigned int            physical_line_partition:10;
 102                 unsigned int            ways_of_associativity:10;
 103         } split;
 104         u32 full;
 105 };
 106
 107 union _cpuid4_leaf_ecx {
 108         struct {
 109                 unsigned int            number_of_sets:32;
 110         } split;
 111         u32 full;
 112 };
 113
 114 struct _cpuid4_info {
 115         union _cpuid4_leaf_eax eax;
 116         union _cpuid4_leaf_ebx ebx;
 117         union _cpuid4_leaf_ecx ecx;
 118         unsigned long size;
 119         cpumask_t shared_cpu_map;
 120 };
 121
 122 static unsigned short                   num_cache_leaves;
 123
 124 static int __cpuinit cpuid4_cache_lookup(int index, struct _cpuid4_info *this_leaf)
 125 {
 126         unsigned int            eax, ebx, ecx, edx;
 127         union _cpuid4_leaf_eax  cache_eax;
 128
 129         cpuid_count(4, index, &eax, &ebx, &ecx, &edx);
 130         cache_eax.full = eax;
 131         if (cache_eax.split.type == CACHE_TYPE_NULL)
 132                 return -EIO; /* better error ? */
 133
 134         this_leaf->eax.full = eax;
 135         this_leaf->ebx.full = ebx;
 136         this_leaf->ecx.full = ecx;
 137         this_leaf->size = (this_leaf->ecx.split.number_of_sets + 1) *
 138                 (this_leaf->ebx.split.coherency_line_size + 1) *
 139                 (this_leaf->ebx.split.physical_line_partition + 1) *
 140                 (this_leaf->ebx.split.ways_of_associativity + 1);
 141         return 0;
 142 }
 143
 144 static int __init find_num_cache_leaves(void)
 145 {
 146         unsigned int            eax, ebx, ecx, edx;
 147         union _cpuid4_leaf_eax  cache_eax;
 148         int                     i = -1;
 149
 150         do {
 151                 ++i;
 152                 /* Do cpuid(4) loop to find out num_cache_leaves */
 153                 cpuid_count(4, i, &eax, &ebx, &ecx, &edx);
 154                 cache_eax.full = eax;
 155         } while (cache_eax.split.type != CACHE_TYPE_NULL);
 156         return i;
 157 }
 158
 159 unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
 160 {
 161         unsigned int trace = 0, l1i = 0, l1d = 0, l2 = 0, l3 = 0; /* Cache sizes */
 162         unsigned int new_l1d = 0, new_l1i = 0; /* Cache sizes from cpuid(4) */
 163         unsigned int new_l2 = 0, new_l3 = 0, i; /* Cache sizes from cpuid(4) */
 164
 165         if (c->cpuid_level > 4) {
 166                 static int is_initialized;
 167
 168                 if (is_initialized == 0) {
 169                         /* Init num_cache_leaves from boot CPU */
 170                         num_cache_leaves = find_num_cache_leaves();
 171                         is_initialized++;
 172                 }
 173
 174                 /*
 175                  * Whenever possible use cpuid(4), deterministic cache
 176                  * parameters cpuid leaf to find the cache details
 177                  */
 178                 for (i = 0; i < num_cache_leaves; i++) {
 179                         struct _cpuid4_info this_leaf;
 180
 181                         int retval;
 182
 183                         retval = cpuid4_cache_lookup(i, &this_leaf);
 184                         if (retval >= 0) {
 185                                 switch(this_leaf.eax.split.level) {
 186                                     case 1:
 187                                         if (this_leaf.eax.split.type ==
 188                                                         CACHE_TYPE_DATA)
 189                                                 new_l1d = this_leaf.size/1024;
 190                                         else if (this_leaf.eax.split.type ==
 191                                                         CACHE_TYPE_INST)
 192                                                 new_l1i = this_leaf.size/1024;
 193                                         break;
 194                                     case 2:
 195                                         new_l2 = this_leaf.size/1024;
 196                                         break;
 197                                     case 3:
 198                                         new_l3 = this_leaf.size/1024;
 199                                         break;
 200                                     default:
 201                                         break;
 202                                 }
 203                         }
 204                 }
 205         }
 206         if (c->cpuid_level > 1) {
 207                 /* supports eax=2  call */
 208                 int i, j, n;
 209                 int regs[4];
 210                 unsigned char *dp = (unsigned char *)regs;
 211
 212                 /* Number of times to iterate */
 213                 n = cpuid_eax(2) & 0xFF;
 214
 215                 for ( i = 0 ; i < n ; i++ ) {
 216                         cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
 217
 218                         /* If bit 31 is set, this is an unknown format */
 219                         for ( j = 0 ; j < 3 ; j++ ) {
 220                                 if ( regs[j] < 0 ) regs[j] = 0;
 221                         }
 222
 223                         /* Byte 0 is level count, not a descriptor */
 224                         for ( j = 1 ; j < 16 ; j++ ) {
 225                                 unsigned char des = dp[j];
 226                                 unsigned char k = 0;
 227
 228                                 /* look up this descriptor in the table */
 229                                 while (cache_table[k].descriptor != 0)
 230                                 {
 231                                         if (cache_table[k].descriptor == des) {
 232                                                 switch (cache_table[k].cache_type) {
 233                                                 case LVL_1_INST:
 234                                                         l1i += cache_table[k].size;
 235                                                         break;
 236                                                 case LVL_1_DATA:
 237                                                         l1d += cache_table[k].size;
 238                                                         break;
 239                                                 case LVL_2:
 240                                                         l2 += cache_table[k].size;
 241                                                         break;
 242                                                 case LVL_3:
 243                                                         l3 += cache_table[k].size;
 244                                                         break;
 245                                                 case LVL_TRACE:
 246                                                         trace += cache_table[k].size;
 247                                                         break;
 248                                                 }
 249
 250                                                 break;
 251                                         }
 252
 253                                         k++;
 254                                 }
 255                         }
 256                 }
 257
 258                 if (new_l1d)
 259                         l1d = new_l1d;
 260
 261                 if (new_l1i)
 262                         l1i = new_l1i;
 263
 264                 if (new_l2)
 265                         l2 = new_l2;
 266
 267                 if (new_l3)
 268                         l3 = new_l3;
 269
 270                 if ( trace )
 271                         printk (KERN_INFO "CPU: Trace cache: %dK uops", trace);
 272                 else if ( l1i )
 273                         printk (KERN_INFO "CPU: L1 I cache: %dK", l1i);
 274                 if ( l1d )
 275                         printk(", L1 D cache: %dK\n", l1d);
 276                 else
 277                         printk("\n");
 278                 if ( l2 )
 279                         printk(KERN_INFO "CPU: L2 cache: %dK\n", l2);
 280                 if ( l3 )
 281                         printk(KERN_INFO "CPU: L3 cache: %dK\n", l3);
 282
 283                 c->x86_cache_size = l3 ? l3 : (l2 ? l2 : (l1i+l1d));
 284         }
 285
 286         return l2;
 287 }
 288
 289 /* pointer to _cpuid4_info array (for each cache leaf) */
 290 static struct _cpuid4_info *cpuid4_info[NR_CPUS];
 291 #define CPUID4_INFO_IDX(x,y)    (&((cpuid4_info[x])[y]))
 292
 293 #ifdef CONFIG_SMP
 294 static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
 295 {
 296         struct _cpuid4_info     *this_leaf, *sibling_leaf;
 297         unsigned long num_threads_sharing;
 298         int index_msb, i;
 299         struct cpuinfo_x86 *c = cpu_data;
 300
 301         this_leaf = CPUID4_INFO_IDX(cpu, index);
 302         num_threads_sharing = 1 + this_leaf->eax.split.num_threads_sharing;
 303
 304         if (num_threads_sharing == 1)
 305                 cpu_set(cpu, this_leaf->shared_cpu_map);
 306         else {
 307                 index_msb = get_count_order(num_threads_sharing);
 308
 309                 for_each_online_cpu(i) {
 310                         if (c[i].apicid >> index_msb ==
 311                             c[cpu].apicid >> index_msb) {
 312                                 cpu_set(i, this_leaf->shared_cpu_map);
 313                                 if (i != cpu && cpuid4_info[i])  {
 314                                         sibling_leaf = CPUID4_INFO_IDX(i, index);
 315                                         cpu_set(cpu, sibling_leaf->shared_cpu_map);
 316                                 }
 317                         }
 318                 }
 319         }
 320 }
 321 static void __devinit cache_remove_shared_cpu_map(unsigned int cpu, int index)
 322 {
 323         struct _cpuid4_info     *this_leaf, *sibling_leaf;
 324         int sibling;
 325
 326         this_leaf = CPUID4_INFO_IDX(cpu, index);
 327         for_each_cpu_mask(sibling, this_leaf->shared_cpu_map) {
 328                 sibling_leaf = CPUID4_INFO_IDX(sibling, index);
 329                 cpu_clear(cpu, sibling_leaf->shared_cpu_map);
 330         }
 331 }
 332 #else
 333 static void __init cache_shared_cpu_map_setup(unsigned int cpu, int index) {}
 334 static void __init cache_remove_shared_cpu_map(unsigned int cpu, int index) {}
 335 #endif
 336
 337 static void free_cache_attributes(unsigned int cpu)
 338 {
 339         kfree(cpuid4_info[cpu]);
 340         cpuid4_info[cpu] = NULL;
 341 }
 342
 343 static int __cpuinit detect_cache_attributes(unsigned int cpu)
 344 {
 345         struct _cpuid4_info     *this_leaf;
 346         unsigned long           j;
 347         int                     retval;
 348         cpumask_t               oldmask;
 349
 350         if (num_cache_leaves == 0)
 351                 return -ENOENT;
 352
 353         cpuid4_info[cpu] = kmalloc(
 354             sizeof(struct _cpuid4_info) * num_cache_leaves, GFP_KERNEL);
 355         if (unlikely(cpuid4_info[cpu] == NULL))
 356                 return -ENOMEM;
 357         memset(cpuid4_info[cpu], 0,
 358             sizeof(struct _cpuid4_info) * num_cache_leaves);
 359
 360         oldmask = current->cpus_allowed;
 361         retval = set_cpus_allowed(current, cpumask_of_cpu(cpu));
 362         if (retval)
 363                 goto out;
 364
 365         /* Do cpuid and store the results */
 366         retval = 0;
 367         for (j = 0; j < num_cache_leaves; j++) {
 368                 this_leaf = CPUID4_INFO_IDX(cpu, j);
 369                 retval = cpuid4_cache_lookup(j, this_leaf);
 370                 if (unlikely(retval < 0))
 371                         break;
 372                 cache_shared_cpu_map_setup(cpu, j);
 373         }
 374         set_cpus_allowed(current, oldmask);
 375
 376 out:
 377         if (retval)
 378                 free_cache_attributes(cpu);
 379         return retval;
 380 }
 381
 382 #ifdef CONFIG_SYSFS
 383
 384 #include <linux/kobject.h>
 385 #include <linux/sysfs.h>
 386
 387 extern struct sysdev_class cpu_sysdev_class; /* from drivers/base/cpu.c */
 388
 389 /* pointer to kobject for cpuX/cache */
 390 static struct kobject * cache_kobject[NR_CPUS];
 391
 392 struct _index_kobject {
 393         struct kobject kobj;
 394         unsigned int cpu;
 395         unsigned short index;
 396 };
 397
 398 /* pointer to array of kobjects for cpuX/cache/indexY */
 399 static struct _index_kobject *index_kobject[NR_CPUS];
 400 #define INDEX_KOBJECT_PTR(x,y)    (&((index_kobject[x])[y]))
 401
 402 #define show_one_plus(file_name, object, val)                           \
 403 static ssize_t show_##file_name                                         \
 404                         (struct _cpuid4_info *this_leaf, char *buf)     \
 405 {                                                                       \
 406         return sprintf (buf, "%lu\n", (unsigned long)this_leaf->object + val); \
 407 }
 408
 409 show_one_plus(level, eax.split.level, 0);
 410 show_one_plus(coherency_line_size, ebx.split.coherency_line_size, 1);
 411 show_one_plus(physical_line_partition, ebx.split.physical_line_partition, 1);
 412 show_one_plus(ways_of_associativity, ebx.split.ways_of_associativity, 1);
 413 show_one_plus(number_of_sets, ecx.split.number_of_sets, 1);
 414
 415 static ssize_t show_size(struct _cpuid4_info *this_leaf, char *buf)
 416 {
 417         return sprintf (buf, "%luK\n", this_leaf->size / 1024);
 418 }
 419
 420 static ssize_t show_shared_cpu_map(struct _cpuid4_info *this_leaf, char *buf)
 421 {
 422         char mask_str[NR_CPUS];
 423         cpumask_scnprintf(mask_str, NR_CPUS, this_leaf->shared_cpu_map);
 424         return sprintf(buf, "%s\n", mask_str);
 425 }
 426
 427 static ssize_t show_type(struct _cpuid4_info *this_leaf, char *buf) {
 428         switch(this_leaf->eax.split.type) {
 429             case CACHE_TYPE_DATA:
 430                 return sprintf(buf, "Data\n");
 431                 break;
 432             case CACHE_TYPE_INST:
 433                 return sprintf(buf, "Instruction\n");
 434                 break;
 435             case CACHE_TYPE_UNIFIED:
 436                 return sprintf(buf, "Unified\n");
 437                 break;
 438             default:
 439                 return sprintf(buf, "Unknown\n");
 440                 break;
 441         }
 442 }
 443
 444 struct _cache_attr {
 445         struct attribute attr;
 446         ssize_t (*show)(struct _cpuid4_info *, char *);
 447         ssize_t (*store)(struct _cpuid4_info *, const char *, size_t count);
 448 };
 449
 450 #define define_one_ro(_name) \
 451 static struct _cache_attr _name = \
 452         __ATTR(_name, 0444, show_##_name, NULL)
 453
 454 define_one_ro(level);
 455 define_one_ro(type);
 456 define_one_ro(coherency_line_size);
 457 define_one_ro(physical_line_partition);
 458 define_one_ro(ways_of_associativity);
 459 define_one_ro(number_of_sets);
 460 define_one_ro(size);
 461 define_one_ro(shared_cpu_map);
 462
 463 static struct attribute * default_attrs[] = {
 464         &type.attr,
 465         &level.attr,
 466         &coherency_line_size.attr,
 467         &physical_line_partition.attr,
 468         &ways_of_associativity.attr,
 469         &number_of_sets.attr,
 470         &size.attr,
 471         &shared_cpu_map.attr,
 472         NULL
 473 };
 474
 475 #define to_object(k) container_of(k, struct _index_kobject, kobj)
 476 #define to_attr(a) container_of(a, struct _cache_attr, attr)
 477
 478 static ssize_t show(struct kobject * kobj, struct attribute * attr, char * buf)
 479 {
 480         struct _cache_attr *fattr = to_attr(attr);
 481         struct _index_kobject *this_leaf = to_object(kobj);
 482         ssize_t ret;
 483
 484         ret = fattr->show ?
 485                 fattr->show(CPUID4_INFO_IDX(this_leaf->cpu, this_leaf->index),
 486                         buf) :
 487                 0;
 488         return ret;
 489 }
 490
 491 static ssize_t store(struct kobject * kobj, struct attribute * attr,
 492                      const char * buf, size_t count)
 493 {
 494         return 0;
 495 }
 496
 497 static struct sysfs_ops sysfs_ops = {
 498         .show   = show,
 499         .store  = store,
 500 };
 501
 502 static struct kobj_type ktype_cache = {
 503         .sysfs_ops      = &sysfs_ops,
 504         .default_attrs  = default_attrs,
 505 };
 506
 507 static struct kobj_type ktype_percpu_entry = {
 508         .sysfs_ops      = &sysfs_ops,
 509 };
 510
 511 static void cpuid4_cache_sysfs_exit(unsigned int cpu)
 512 {
 513         kfree(cache_kobject[cpu]);
 514         kfree(index_kobject[cpu]);
 515         cache_kobject[cpu] = NULL;
 516         index_kobject[cpu] = NULL;
 517         free_cache_attributes(cpu);
 518 }
 519
 520 static int __cpuinit cpuid4_cache_sysfs_init(unsigned int cpu)
 521 {
 522
 523         if (num_cache_leaves == 0)
 524                 return -ENOENT;
 525
 526         detect_cache_attributes(cpu);
 527         if (cpuid4_info[cpu] == NULL)
 528                 return -ENOENT;
 529
 530         /* Allocate all required memory */
 531         cache_kobject[cpu] = kmalloc(sizeof(struct kobject), GFP_KERNEL);
 532         if (unlikely(cache_kobject[cpu] == NULL))
 533                 goto err_out;
 534         memset(cache_kobject[cpu], 0, sizeof(struct kobject));
 535
 536         index_kobject[cpu] = kmalloc(
 537             sizeof(struct _index_kobject ) * num_cache_leaves, GFP_KERNEL);
 538         if (unlikely(index_kobject[cpu] == NULL))
 539                 goto err_out;
 540         memset(index_kobject[cpu], 0,
 541             sizeof(struct _index_kobject) * num_cache_leaves);
 542
 543         return 0;
 544
 545 err_out:
 546         cpuid4_cache_sysfs_exit(cpu);
 547         return -ENOMEM;
 548 }
 549
 550 /* Add/Remove cache interface for CPU device */
 551 static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
 552 {
 553         unsigned int cpu = sys_dev->id;
 554         unsigned long i, j;
 555         struct _index_kobject *this_object;
 556         int retval = 0;
 557
 558         retval = cpuid4_cache_sysfs_init(cpu);
 559         if (unlikely(retval < 0))
 560                 return retval;
 561
 562         cache_kobject[cpu]->parent = &sys_dev->kobj;
 563         kobject_set_name(cache_kobject[cpu], "%s", "cache");
 564         cache_kobject[cpu]->ktype = &ktype_percpu_entry;
 565         retval = kobject_register(cache_kobject[cpu]);
 566
 567         for (i = 0; i < num_cache_leaves; i++) {
 568                 this_object = INDEX_KOBJECT_PTR(cpu,i);
 569                 this_object->cpu = cpu;
 570                 this_object->index = i;
 571                 this_object->kobj.parent = cache_kobject[cpu];
 572                 kobject_set_name(&(this_object->kobj), "index%1lu", i);
 573                 this_object->kobj.ktype = &ktype_cache;
 574                 retval = kobject_register(&(this_object->kobj));
 575                 if (unlikely(retval)) {
 576                         for (j = 0; j < i; j++) {
 577                                 kobject_unregister(
 578                                         &(INDEX_KOBJECT_PTR(cpu,j)->kobj));
 579                         }
 580                         kobject_unregister(cache_kobject[cpu]);
 581                         cpuid4_cache_sysfs_exit(cpu);
 582                         break;
 583                 }
 584         }
 585         return retval;
 586 }
 587
 588 static void __cpuexit cache_remove_dev(struct sys_device * sys_dev)
 589 {
 590         unsigned int cpu = sys_dev->id;
 591         unsigned long i;
 592
 593         for (i = 0; i < num_cache_leaves; i++) {
 594                 cache_remove_shared_cpu_map(cpu, i);
 595                 kobject_unregister(&(INDEX_KOBJECT_PTR(cpu,i)->kobj));
 596         }
 597         kobject_unregister(cache_kobject[cpu]);
 598         cpuid4_cache_sysfs_exit(cpu);
 599         return;
 600 }
 601
 602 static int __cpuinit cacheinfo_cpu_callback(struct notifier_block *nfb,
 603                                         unsigned long action, void *hcpu)
 604 {
 605         unsigned int cpu = (unsigned long)hcpu;
 606         struct sys_device *sys_dev;
 607
 608         sys_dev = get_cpu_sysdev(cpu);
 609         switch (action) {
 610         case CPU_ONLINE:
 611                 cache_add_dev(sys_dev);
 612                 break;
 613         case CPU_DEAD:
 614                 cache_remove_dev(sys_dev);
 615                 break;
 616         }
 617         return NOTIFY_OK;
 618 }
 619
 620 static struct notifier_block cacheinfo_cpu_notifier =
 621 {
 622     .notifier_call = cacheinfo_cpu_callback,
 623 };
 624
 625 static int __cpuinit cache_sysfs_init(void)
 626 {
 627         int i;
 628
 629         if (num_cache_leaves == 0)
 630                 return 0;
 631
 632         register_cpu_notifier(&cacheinfo_cpu_notifier);
 633
 634         for_each_online_cpu(i) {
 635                 cacheinfo_cpu_callback(&cacheinfo_cpu_notifier, CPU_ONLINE,
 636                         (void *)(long)i);
 637         }
 638
 639         return 0;
 640 }
 641
 642 device_initcall(cache_sysfs_init);
 643
 644 #endif