arch/x86/oprofile/nmi_int.c

   1 /**
   2  * @file nmi_int.c
   3  *
   4  * @remark Copyright 2002-2009 OProfile authors
   5  * @remark Read the file COPYING
   6  *
   7  * @author John Levon <levon@movementarian.org>
   8  * @author Robert Richter <robert.richter@amd.com>
   9  * @author Barry Kasindorf <barry.kasindorf@amd.com>
  10  * @author Jason Yeh <jason.yeh@amd.com>
  11  * @author Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
  12  */
  13
  14 #include <linux/init.h>
  15 #include <linux/notifier.h>
  16 #include <linux/smp.h>
  17 #include <linux/oprofile.h>
  18 #include <linux/syscore_ops.h>
  19 #include <linux/slab.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/kdebug.h>
  22 #include <linux/cpu.h>
  23 #include <asm/nmi.h>
  24 #include <asm/msr.h>
  25 #include <asm/apic.h>
  26
  27 #include "op_counter.h"
  28 #include "op_x86_model.h"
  29
  30 static struct op_x86_model_spec *model;
  31 static DEFINE_PER_CPU(struct op_msrs, cpu_msrs);
  32 static DEFINE_PER_CPU(unsigned long, saved_lvtpc);
  33
  34 /* must be protected with get_online_cpus()/put_online_cpus(): */
  35 static int nmi_enabled;
  36 static int ctr_running;
  37
  38 struct op_counter_config counter_config[OP_MAX_COUNTER];
  39
  40 /* common functions */
  41
  42 u64 op_x86_get_ctrl(struct op_x86_model_spec const *model,
  43                     struct op_counter_config *counter_config)
  44 {
  45         u64 val = 0;
  46         u16 event = (u16)counter_config->event;
  47
  48         val |= ARCH_PERFMON_EVENTSEL_INT;
  49         val |= counter_config->user ? ARCH_PERFMON_EVENTSEL_USR : 0;
  50         val |= counter_config->kernel ? ARCH_PERFMON_EVENTSEL_OS : 0;
  51         val |= (counter_config->unit_mask & 0xFF) << 8;
  52         counter_config->extra &= (ARCH_PERFMON_EVENTSEL_INV |
  53                                   ARCH_PERFMON_EVENTSEL_EDGE |
  54                                   ARCH_PERFMON_EVENTSEL_CMASK);
  55         val |= counter_config->extra;
  56         event &= model->event_mask ? model->event_mask : 0xFF;
  57         val |= event & 0xFF;
  58         val |= (u64)(event & 0x0F00) << 24;
  59
  60         return val;
  61 }
  62
  63
  64 static int profile_exceptions_notify(unsigned int val, struct pt_regs *regs)
  65 {
  66         if (ctr_running)
  67                 model->check_ctrs(regs, this_cpu_ptr(&cpu_msrs));
  68         else if (!nmi_enabled)
  69                 return NMI_DONE;
  70         else
  71                 model->stop(this_cpu_ptr(&cpu_msrs));
  72         return NMI_HANDLED;
  73 }
  74
  75 static void nmi_cpu_save_registers(struct op_msrs *msrs)
  76 {
  77         struct op_msr *counters = msrs->counters;
  78         struct op_msr *controls = msrs->controls;
  79         unsigned int i;
  80
  81         for (i = 0; i < model->num_counters; ++i) {
  82                 if (counters[i].addr)
  83                         rdmsrl(counters[i].addr, counters[i].saved);
  84         }
  85
  86         for (i = 0; i < model->num_controls; ++i) {
  87                 if (controls[i].addr)
  88                         rdmsrl(controls[i].addr, controls[i].saved);
  89         }
  90 }
  91
  92 static void nmi_cpu_start(void *dummy)
  93 {
  94         struct op_msrs const *msrs = this_cpu_ptr(&cpu_msrs);
  95         if (!msrs->controls)
  96                 WARN_ON_ONCE(1);
  97         else
  98                 model->start(msrs);
  99 }
 100
 101 static int nmi_start(void)
 102 {
 103         get_online_cpus();
 104         ctr_running = 1;
 105         /* make ctr_running visible to the nmi handler: */
 106         smp_mb();
 107         on_each_cpu(nmi_cpu_start, NULL, 1);
 108         put_online_cpus();
 109         return 0;
 110 }
 111
 112 static void nmi_cpu_stop(void *dummy)
 113 {
 114         struct op_msrs const *msrs = this_cpu_ptr(&cpu_msrs);
 115         if (!msrs->controls)
 116                 WARN_ON_ONCE(1);
 117         else
 118                 model->stop(msrs);
 119 }
 120
 121 static void nmi_stop(void)
 122 {
 123         get_online_cpus();
 124         on_each_cpu(nmi_cpu_stop, NULL, 1);
 125         ctr_running = 0;
 126         put_online_cpus();
 127 }
 128
 129 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
 130
 131 static DEFINE_PER_CPU(int, switch_index);
 132
 133 static inline int has_mux(void)
 134 {
 135         return !!model->switch_ctrl;
 136 }
 137
 138 inline int op_x86_phys_to_virt(int phys)
 139 {
 140         return __this_cpu_read(switch_index) + phys;
 141 }
 142
 143 inline int op_x86_virt_to_phys(int virt)
 144 {
 145         return virt % model->num_counters;
 146 }
 147
 148 static void nmi_shutdown_mux(void)
 149 {
 150         int i;
 151
 152         if (!has_mux())
 153                 return;
 154
 155         for_each_possible_cpu(i) {
 156                 kfree(per_cpu(cpu_msrs, i).multiplex);
 157                 per_cpu(cpu_msrs, i).multiplex = NULL;
 158                 per_cpu(switch_index, i) = 0;
 159         }
 160 }
 161
 162 static int nmi_setup_mux(void)
 163 {
 164         size_t multiplex_size =
 165                 sizeof(struct op_msr) * model->num_virt_counters;
 166         int i;
 167
 168         if (!has_mux())
 169                 return 1;
 170
 171         for_each_possible_cpu(i) {
 172                 per_cpu(cpu_msrs, i).multiplex =
 173                         kzalloc(multiplex_size, GFP_KERNEL);
 174                 if (!per_cpu(cpu_msrs, i).multiplex)
 175                         return 0;
 176         }
 177
 178         return 1;
 179 }
 180
 181 static void nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs)
 182 {
 183         int i;
 184         struct op_msr *multiplex = msrs->multiplex;
 185
 186         if (!has_mux())
 187                 return;
 188
 189         for (i = 0; i < model->num_virt_counters; ++i) {
 190                 if (counter_config[i].enabled) {
 191                         multiplex[i].saved = -(u64)counter_config[i].count;
 192                 } else {
 193                         multiplex[i].saved = 0;
 194                 }
 195         }
 196
 197         per_cpu(switch_index, cpu) = 0;
 198 }
 199
 200 static void nmi_cpu_save_mpx_registers(struct op_msrs *msrs)
 201 {
 202         struct op_msr *counters = msrs->counters;
 203         struct op_msr *multiplex = msrs->multiplex;
 204         int i;
 205
 206         for (i = 0; i < model->num_counters; ++i) {
 207                 int virt = op_x86_phys_to_virt(i);
 208                 if (counters[i].addr)
 209                         rdmsrl(counters[i].addr, multiplex[virt].saved);
 210         }
 211 }
 212
 213 static void nmi_cpu_restore_mpx_registers(struct op_msrs *msrs)
 214 {
 215         struct op_msr *counters = msrs->counters;
 216         struct op_msr *multiplex = msrs->multiplex;
 217         int i;
 218
 219         for (i = 0; i < model->num_counters; ++i) {
 220                 int virt = op_x86_phys_to_virt(i);
 221                 if (counters[i].addr)
 222                         wrmsrl(counters[i].addr, multiplex[virt].saved);
 223         }
 224 }
 225
 226 static void nmi_cpu_switch(void *dummy)
 227 {
 228         int cpu = smp_processor_id();
 229         int si = per_cpu(switch_index, cpu);
 230         struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
 231
 232         nmi_cpu_stop(NULL);
 233         nmi_cpu_save_mpx_registers(msrs);
 234
 235         /* move to next set */
 236         si += model->num_counters;
 237         if ((si >= model->num_virt_counters) || (counter_config[si].count == 0))
 238                 per_cpu(switch_index, cpu) = 0;
 239         else
 240                 per_cpu(switch_index, cpu) = si;
 241
 242         model->switch_ctrl(model, msrs);
 243         nmi_cpu_restore_mpx_registers(msrs);
 244
 245         nmi_cpu_start(NULL);
 246 }
 247
 248
 249 /*
 250  * Quick check to see if multiplexing is necessary.
 251  * The check should be sufficient since counters are used
 252  * in ordre.
 253  */
 254 static int nmi_multiplex_on(void)
 255 {
 256         return counter_config[model->num_counters].count ? 0 : -EINVAL;
 257 }
 258
 259 static int nmi_switch_event(void)
 260 {
 261         if (!has_mux())
 262                 return -ENOSYS;         /* not implemented */
 263         if (nmi_multiplex_on() < 0)
 264                 return -EINVAL;         /* not necessary */
 265
 266         get_online_cpus();
 267         if (ctr_running)
 268                 on_each_cpu(nmi_cpu_switch, NULL, 1);
 269         put_online_cpus();
 270
 271         return 0;
 272 }
 273
 274 static inline void mux_init(struct oprofile_operations *ops)
 275 {
 276         if (has_mux())
 277                 ops->switch_events = nmi_switch_event;
 278 }
 279
 280 static void mux_clone(int cpu)
 281 {
 282         if (!has_mux())
 283                 return;
 284
 285         memcpy(per_cpu(cpu_msrs, cpu).multiplex,
 286                per_cpu(cpu_msrs, 0).multiplex,
 287                sizeof(struct op_msr) * model->num_virt_counters);
 288 }
 289
 290 #else
 291
 292 inline int op_x86_phys_to_virt(int phys) { return phys; }
 293 inline int op_x86_virt_to_phys(int virt) { return virt; }
 294 static inline void nmi_shutdown_mux(void) { }
 295 static inline int nmi_setup_mux(void) { return 1; }
 296 static inline void
 297 nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs) { }
 298 static inline void mux_init(struct oprofile_operations *ops) { }
 299 static void mux_clone(int cpu) { }
 300
 301 #endif
 302
 303 static void free_msrs(void)
 304 {
 305         int i;
 306         for_each_possible_cpu(i) {
 307                 kfree(per_cpu(cpu_msrs, i).counters);
 308                 per_cpu(cpu_msrs, i).counters = NULL;
 309                 kfree(per_cpu(cpu_msrs, i).controls);
 310                 per_cpu(cpu_msrs, i).controls = NULL;
 311         }
 312         nmi_shutdown_mux();
 313 }
 314
 315 static int allocate_msrs(void)
 316 {
 317         size_t controls_size = sizeof(struct op_msr) * model->num_controls;
 318         size_t counters_size = sizeof(struct op_msr) * model->num_counters;
 319
 320         int i;
 321         for_each_possible_cpu(i) {
 322                 per_cpu(cpu_msrs, i).counters = kzalloc(counters_size,
 323                                                         GFP_KERNEL);
 324                 if (!per_cpu(cpu_msrs, i).counters)
 325                         goto fail;
 326                 per_cpu(cpu_msrs, i).controls = kzalloc(controls_size,
 327                                                         GFP_KERNEL);
 328                 if (!per_cpu(cpu_msrs, i).controls)
 329                         goto fail;
 330         }
 331
 332         if (!nmi_setup_mux())
 333                 goto fail;
 334
 335         return 1;
 336
 337 fail:
 338         free_msrs();
 339         return 0;
 340 }
 341
 342 static void nmi_cpu_setup(void *dummy)
 343 {
 344         int cpu = smp_processor_id();
 345         struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
 346         nmi_cpu_save_registers(msrs);
 347         raw_spin_lock(&oprofilefs_lock);
 348         model->setup_ctrs(model, msrs);
 349         nmi_cpu_setup_mux(cpu, msrs);
 350         raw_spin_unlock(&oprofilefs_lock);
 351         per_cpu(saved_lvtpc, cpu) = apic_read(APIC_LVTPC);
 352         apic_write(APIC_LVTPC, APIC_DM_NMI);
 353 }
 354
 355 static void nmi_cpu_restore_registers(struct op_msrs *msrs)
 356 {
 357         struct op_msr *counters = msrs->counters;
 358         struct op_msr *controls = msrs->controls;
 359         unsigned int i;
 360
 361         for (i = 0; i < model->num_controls; ++i) {
 362                 if (controls[i].addr)
 363                         wrmsrl(controls[i].addr, controls[i].saved);
 364         }
 365
 366         for (i = 0; i < model->num_counters; ++i) {
 367                 if (counters[i].addr)
 368                         wrmsrl(counters[i].addr, counters[i].saved);
 369         }
 370 }
 371
 372 static void nmi_cpu_shutdown(void *dummy)
 373 {
 374         unsigned int v;
 375         int cpu = smp_processor_id();
 376         struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu);
 377
 378         /* restoring APIC_LVTPC can trigger an apic error because the delivery
 379          * mode and vector nr combination can be illegal. That's by design: on
 380          * power on apic lvt contain a zero vector nr which are legal only for
 381          * NMI delivery mode. So inhibit apic err before restoring lvtpc
 382          */
 383         v = apic_read(APIC_LVTERR);
 384         apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
 385         apic_write(APIC_LVTPC, per_cpu(saved_lvtpc, cpu));
 386         apic_write(APIC_LVTERR, v);
 387         nmi_cpu_restore_registers(msrs);
 388 }
 389
 390 static void nmi_cpu_up(void *dummy)
 391 {
 392         if (nmi_enabled)
 393                 nmi_cpu_setup(dummy);
 394         if (ctr_running)
 395                 nmi_cpu_start(dummy);
 396 }
 397
 398 static void nmi_cpu_down(void *dummy)
 399 {
 400         if (ctr_running)
 401                 nmi_cpu_stop(dummy);
 402         if (nmi_enabled)
 403                 nmi_cpu_shutdown(dummy);
 404 }
 405
 406 static int nmi_create_files(struct dentry *root)
 407 {
 408         unsigned int i;
 409
 410         for (i = 0; i < model->num_virt_counters; ++i) {
 411                 struct dentry *dir;
 412                 char buf[4];
 413
 414                 /* quick little hack to _not_ expose a counter if it is not
 415                  * available for use.  This should protect userspace app.
 416                  * NOTE:  assumes 1:1 mapping here (that counters are organized
 417                  *        sequentially in their struct assignment).
 418                  */
 419                 if (!avail_to_resrv_perfctr_nmi_bit(op_x86_virt_to_phys(i)))
 420                         continue;
 421
 422                 snprintf(buf,  sizeof(buf), "%d", i);
 423                 dir = oprofilefs_mkdir(root, buf);
 424                 oprofilefs_create_ulong(dir, "enabled", &counter_config[i].enabled);
 425                 oprofilefs_create_ulong(dir, "event", &counter_config[i].event);
 426                 oprofilefs_create_ulong(dir, "count", &counter_config[i].count);
 427                 oprofilefs_create_ulong(dir, "unit_mask", &counter_config[i].unit_mask);
 428                 oprofilefs_create_ulong(dir, "kernel", &counter_config[i].kernel);
 429                 oprofilefs_create_ulong(dir, "user", &counter_config[i].user);
 430                 oprofilefs_create_ulong(dir, "extra", &counter_config[i].extra);
 431         }
 432
 433         return 0;
 434 }
 435
 436 static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
 437                                  void *data)
 438 {
 439         int cpu = (unsigned long)data;
 440
 441         switch (action & ~CPU_TASKS_FROZEN) {
 442         case CPU_DOWN_FAILED:
 443         case CPU_ONLINE:
 444                 smp_call_function_single(cpu, nmi_cpu_up, NULL, 0);
 445                 break;
 446         case CPU_DOWN_PREPARE:
 447                 smp_call_function_single(cpu, nmi_cpu_down, NULL, 1);
 448                 break;
 449         }
 450         return NOTIFY_DONE;
 451 }
 452
 453 static struct notifier_block oprofile_cpu_nb = {
 454         .notifier_call = oprofile_cpu_notifier
 455 };
 456
 457 static int nmi_setup(void)
 458 {
 459         int err = 0;
 460         int cpu;
 461
 462         if (!allocate_msrs())
 463                 return -ENOMEM;
 464
 465         /* We need to serialize save and setup for HT because the subset
 466          * of msrs are distinct for save and setup operations
 467          */
 468
 469         /* Assume saved/restored counters are the same on all CPUs */
 470         err = model->fill_in_addresses(&per_cpu(cpu_msrs, 0));
 471         if (err)
 472                 goto fail;
 473
 474         for_each_possible_cpu(cpu) {
 475                 if (!cpu)
 476                         continue;
 477
 478                 memcpy(per_cpu(cpu_msrs, cpu).counters,
 479                        per_cpu(cpu_msrs, 0).counters,
 480                        sizeof(struct op_msr) * model->num_counters);
 481
 482                 memcpy(per_cpu(cpu_msrs, cpu).controls,
 483                        per_cpu(cpu_msrs, 0).controls,
 484                        sizeof(struct op_msr) * model->num_controls);
 485
 486                 mux_clone(cpu);
 487         }
 488
 489         nmi_enabled = 0;
 490         ctr_running = 0;
 491         /* make variables visible to the nmi handler: */
 492         smp_mb();
 493         err = register_nmi_handler(NMI_LOCAL, profile_exceptions_notify,
 494                                         0, "oprofile");
 495         if (err)
 496                 goto fail;
 497
 498         cpu_notifier_register_begin();
 499
 500         /* Use get/put_online_cpus() to protect 'nmi_enabled' */
 501         get_online_cpus();
 502         nmi_enabled = 1;
 503         /* make nmi_enabled visible to the nmi handler: */
 504         smp_mb();
 505         on_each_cpu(nmi_cpu_setup, NULL, 1);
 506         __register_cpu_notifier(&oprofile_cpu_nb);
 507         put_online_cpus();
 508
 509         cpu_notifier_register_done();
 510
 511         return 0;
 512 fail:
 513         free_msrs();
 514         return err;
 515 }
 516
 517 static void nmi_shutdown(void)
 518 {
 519         struct op_msrs *msrs;
 520
 521         cpu_notifier_register_begin();
 522
 523         /* Use get/put_online_cpus() to protect 'nmi_enabled' & 'ctr_running' */
 524         get_online_cpus();
 525         on_each_cpu(nmi_cpu_shutdown, NULL, 1);
 526         nmi_enabled = 0;
 527         ctr_running = 0;
 528         __unregister_cpu_notifier(&oprofile_cpu_nb);
 529         put_online_cpus();
 530
 531         cpu_notifier_register_done();
 532
 533         /* make variables visible to the nmi handler: */
 534         smp_mb();
 535         unregister_nmi_handler(NMI_LOCAL, "oprofile");
 536         msrs = &get_cpu_var(cpu_msrs);
 537         model->shutdown(msrs);
 538         free_msrs();
 539         put_cpu_var(cpu_msrs);
 540 }
 541
 542 #ifdef CONFIG_PM
 543
 544 static int nmi_suspend(void)
 545 {
 546         /* Only one CPU left, just stop that one */
 547         if (nmi_enabled == 1)
 548                 nmi_cpu_stop(NULL);
 549         return 0;
 550 }
 551
 552 static void nmi_resume(void)
 553 {
 554         if (nmi_enabled == 1)
 555                 nmi_cpu_start(NULL);
 556 }
 557
 558 static struct syscore_ops oprofile_syscore_ops = {
 559         .resume         = nmi_resume,
 560         .suspend        = nmi_suspend,
 561 };
 562
 563 static void __init init_suspend_resume(void)
 564 {
 565         register_syscore_ops(&oprofile_syscore_ops);
 566 }
 567
 568 static void exit_suspend_resume(void)
 569 {
 570         unregister_syscore_ops(&oprofile_syscore_ops);
 571 }
 572
 573 #else
 574
 575 static inline void init_suspend_resume(void) { }
 576 static inline void exit_suspend_resume(void) { }
 577
 578 #endif /* CONFIG_PM */
 579
 580 static int __init p4_init(char **cpu_type)
 581 {
 582         __u8 cpu_model = boot_cpu_data.x86_model;
 583
 584         if (cpu_model > 6 || cpu_model == 5)
 585                 return 0;
 586
 587 #ifndef CONFIG_SMP
 588         *cpu_type = "i386/p4";
 589         model = &op_p4_spec;
 590         return 1;
 591 #else
 592         switch (smp_num_siblings) {
 593         case 1:
 594                 *cpu_type = "i386/p4";
 595                 model = &op_p4_spec;
 596                 return 1;
 597
 598         case 2:
 599                 *cpu_type = "i386/p4-ht";
 600                 model = &op_p4_ht2_spec;
 601                 return 1;
 602         }
 603 #endif
 604
 605         printk(KERN_INFO "oprofile: P4 HyperThreading detected with > 2 threads\n");
 606         printk(KERN_INFO "oprofile: Reverting to timer mode.\n");
 607         return 0;
 608 }
 609
 610 enum __force_cpu_type {
 611         reserved = 0,           /* do not force */
 612         timer,
 613         arch_perfmon,
 614 };
 615
 616 static int force_cpu_type;
 617
 618 static int set_cpu_type(const char *str, struct kernel_param *kp)
 619 {
 620         if (!strcmp(str, "timer")) {
 621                 force_cpu_type = timer;
 622                 printk(KERN_INFO "oprofile: forcing NMI timer mode\n");
 623         } else if (!strcmp(str, "arch_perfmon")) {
 624                 force_cpu_type = arch_perfmon;
 625                 printk(KERN_INFO "oprofile: forcing architectural perfmon\n");
 626         } else {
 627                 force_cpu_type = 0;
 628         }
 629
 630         return 0;
 631 }
 632 module_param_call(cpu_type, set_cpu_type, NULL, NULL, 0);
 633
 634 static int __init ppro_init(char **cpu_type)
 635 {
 636         __u8 cpu_model = boot_cpu_data.x86_model;
 637         struct op_x86_model_spec *spec = &op_ppro_spec; /* default */
 638
 639         if (force_cpu_type == arch_perfmon && boot_cpu_has(X86_FEATURE_ARCH_PERFMON))
 640                 return 0;
 641
 642         /*
 643          * Documentation on identifying Intel processors by CPU family
 644          * and model can be found in the Intel Software Developer's
 645          * Manuals (SDM):
 646          *
 647          *  http://www.intel.com/products/processor/manuals/
 648          *
 649          * As of May 2010 the documentation for this was in the:
 650          * "Intel 64 and IA-32 Architectures Software Developer's
 651          * Manual Volume 3B: System Programming Guide", "Table B-1
 652          * CPUID Signature Values of DisplayFamily_DisplayModel".
 653          */
 654         switch (cpu_model) {
 655         case 0 ... 2:
 656                 *cpu_type = "i386/ppro";
 657                 break;
 658         case 3 ... 5:
 659                 *cpu_type = "i386/pii";
 660                 break;
 661         case 6 ... 8:
 662         case 10 ... 11:
 663                 *cpu_type = "i386/piii";
 664                 break;
 665         case 9:
 666         case 13:
 667                 *cpu_type = "i386/p6_mobile";
 668                 break;
 669         case 14:
 670                 *cpu_type = "i386/core";
 671                 break;
 672         case 0x0f:
 673         case 0x16:
 674         case 0x17:
 675         case 0x1d:
 676                 *cpu_type = "i386/core_2";
 677                 break;
 678         case 0x1a:
 679         case 0x1e:
 680         case 0x2e:
 681                 spec = &op_arch_perfmon_spec;
 682                 *cpu_type = "i386/core_i7";
 683                 break;
 684         case 0x1c:
 685                 *cpu_type = "i386/atom";
 686                 break;
 687         default:
 688                 /* Unknown */
 689                 return 0;
 690         }
 691
 692         model = spec;
 693         return 1;
 694 }
 695
 696 int __init op_nmi_init(struct oprofile_operations *ops)
 697 {
 698         __u8 vendor = boot_cpu_data.x86_vendor;
 699         __u8 family = boot_cpu_data.x86;
 700         char *cpu_type = NULL;
 701         int ret = 0;
 702
 703         if (!boot_cpu_has(X86_FEATURE_APIC))
 704                 return -ENODEV;
 705
 706         if (force_cpu_type == timer)
 707                 return -ENODEV;
 708
 709         switch (vendor) {
 710         case X86_VENDOR_AMD:
 711                 /* Needs to be at least an Athlon (or hammer in 32bit mode) */
 712
 713                 switch (family) {
 714                 case 6:
 715                         cpu_type = "i386/athlon";
 716                         break;
 717                 case 0xf:
 718                         /*
 719                          * Actually it could be i386/hammer too, but
 720                          * give user space an consistent name.
 721                          */
 722                         cpu_type = "x86-64/hammer";
 723                         break;
 724                 case 0x10:
 725                         cpu_type = "x86-64/family10";
 726                         break;
 727                 case 0x11:
 728                         cpu_type = "x86-64/family11h";
 729                         break;
 730                 case 0x12:
 731                         cpu_type = "x86-64/family12h";
 732                         break;
 733                 case 0x14:
 734                         cpu_type = "x86-64/family14h";
 735                         break;
 736                 case 0x15:
 737                         cpu_type = "x86-64/family15h";
 738                         break;
 739                 default:
 740                         return -ENODEV;
 741                 }
 742                 model = &op_amd_spec;
 743                 break;
 744
 745         case X86_VENDOR_INTEL:
 746                 switch (family) {
 747                         /* Pentium IV */
 748                 case 0xf:
 749                         p4_init(&cpu_type);
 750                         break;
 751
 752                         /* A P6-class processor */
 753                 case 6:
 754                         ppro_init(&cpu_type);
 755                         break;
 756
 757                 default:
 758                         break;
 759                 }
 760
 761                 if (cpu_type)
 762                         break;
 763
 764                 if (!boot_cpu_has(X86_FEATURE_ARCH_PERFMON))
 765                         return -ENODEV;
 766
 767                 /* use arch perfmon as fallback */
 768                 cpu_type = "i386/arch_perfmon";
 769                 model = &op_arch_perfmon_spec;
 770                 break;
 771
 772         default:
 773                 return -ENODEV;
 774         }
 775
 776         /* default values, can be overwritten by model */
 777         ops->create_files       = nmi_create_files;
 778         ops->setup              = nmi_setup;
 779         ops->shutdown           = nmi_shutdown;
 780         ops->start              = nmi_start;
 781         ops->stop               = nmi_stop;
 782         ops->cpu_type           = cpu_type;
 783
 784         if (model->init)
 785                 ret = model->init(ops);
 786         if (ret)
 787                 return ret;
 788
 789         if (!model->num_virt_counters)
 790                 model->num_virt_counters = model->num_counters;
 791
 792         mux_init(ops);
 793
 794         init_suspend_resume();
 795
 796         printk(KERN_INFO "oprofile: using NMI interrupt.\n");
 797         return 0;
 798 }
 799
 800 void op_nmi_exit(void)
 801 {
 802         exit_suspend_resume();
 803 }