arch/x86/xen/smp.c

   1 /*
   2  * Xen SMP support
   3  *
   4  * This file implements the Xen versions of smp_ops.  SMP under Xen is
   5  * very straightforward.  Bringing a CPU up is simply a matter of
   6  * loading its initial context and setting it running.
   7  *
   8  * IPIs are handled through the Xen event mechanism.
   9  *
  10  * Because virtual CPUs can be scheduled onto any real CPU, there's no
  11  * useful topology information for the kernel to make use of.  As a
  12  * result, all CPUs are treated as if they're single-core and
  13  * single-threaded.
  14  */
  15 #include <linux/sched.h>
  16 #include <linux/err.h>
  17 #include <linux/slab.h>
  18 #include <linux/smp.h>
  19 #include <linux/irq_work.h>
  20 #include <linux/tick.h>
  21
  22 #include <asm/paravirt.h>
  23 #include <asm/desc.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/cpu.h>
  26
  27 #include <xen/interface/xen.h>
  28 #include <xen/interface/vcpu.h>
  29
  30 #include <asm/xen/interface.h>
  31 #include <asm/xen/hypercall.h>
  32
  33 #include <xen/xen.h>
  34 #include <xen/page.h>
  35 #include <xen/events.h>
  36
  37 #include <xen/hvc-console.h>
  38 #include "xen-ops.h"
  39 #include "mmu.h"
  40
  41 cpumask_var_t xen_cpu_initialized_map;
  42
  43 static DEFINE_PER_CPU(int, xen_resched_irq);
  44 static DEFINE_PER_CPU(int, xen_callfunc_irq);
  45 static DEFINE_PER_CPU(int, xen_callfuncsingle_irq);
  46 static DEFINE_PER_CPU(int, xen_irq_work);
  47 static DEFINE_PER_CPU(int, xen_debug_irq) = -1;
  48
  49 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
  50 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
  51 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id);
  52
  53 /*
  54  * Reschedule call back.
  55  */
  56 static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
  57 {
  58         inc_irq_stat(irq_resched_count);
  59         scheduler_ipi();
  60
  61         return IRQ_HANDLED;
  62 }
  63
  64 static void __cpuinit cpu_bringup(void)
  65 {
  66         int cpu;
  67
  68         cpu_init();
  69         touch_softlockup_watchdog();
  70         preempt_disable();
  71
  72         xen_enable_sysenter();
  73         xen_enable_syscall();
  74
  75         cpu = smp_processor_id();
  76         smp_store_cpu_info(cpu);
  77         cpu_data(cpu).x86_max_cores = 1;
  78         set_cpu_sibling_map(cpu);
  79
  80         xen_setup_cpu_clockevents();
  81
  82         notify_cpu_starting(cpu);
  83
  84         set_cpu_online(cpu, true);
  85
  86         this_cpu_write(cpu_state, CPU_ONLINE);
  87
  88         wmb();
  89
  90         /* We can take interrupts now: we're officially "up". */
  91         local_irq_enable();
  92
  93         wmb();                  /* make sure everything is out */
  94 }
  95
  96 static void __cpuinit cpu_bringup_and_idle(void)
  97 {
  98         cpu_bringup();
  99         cpu_startup_entry(CPUHP_ONLINE);
 100 }
 101
 102 static int xen_smp_intr_init(unsigned int cpu)
 103 {
 104         int rc;
 105         const char *resched_name, *callfunc_name, *debug_name;
 106
 107         resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
 108         rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
 109                                     cpu,
 110                                     xen_reschedule_interrupt,
 111                                     IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
 112                                     resched_name,
 113                                     NULL);
 114         if (rc < 0)
 115                 goto fail;
 116         per_cpu(xen_resched_irq, cpu) = rc;
 117
 118         callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
 119         rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
 120                                     cpu,
 121                                     xen_call_function_interrupt,
 122                                     IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
 123                                     callfunc_name,
 124                                     NULL);
 125         if (rc < 0)
 126                 goto fail;
 127         per_cpu(xen_callfunc_irq, cpu) = rc;
 128
 129         debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
 130         rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
 131                                      IRQF_DISABLED | IRQF_PERCPU | IRQF_NOBALANCING,
 132                                      debug_name, NULL);
 133         if (rc < 0)
 134                 goto fail;
 135         per_cpu(xen_debug_irq, cpu) = rc;
 136
 137         callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
 138         rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
 139                                     cpu,
 140                                     xen_call_function_single_interrupt,
 141                                     IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
 142                                     callfunc_name,
 143                                     NULL);
 144         if (rc < 0)
 145                 goto fail;
 146         per_cpu(xen_callfuncsingle_irq, cpu) = rc;
 147
 148         /*
 149          * The IRQ worker on PVHVM goes through the native path and uses the
 150          * IPI mechanism.
 151          */
 152         if (xen_hvm_domain())
 153                 return 0;
 154
 155         callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu);
 156         rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR,
 157                                     cpu,
 158                                     xen_irq_work_interrupt,
 159                                     IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
 160                                     callfunc_name,
 161                                     NULL);
 162         if (rc < 0)
 163                 goto fail;
 164         per_cpu(xen_irq_work, cpu) = rc;
 165
 166         return 0;
 167
 168  fail:
 169         if (per_cpu(xen_resched_irq, cpu) >= 0)
 170                 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
 171         if (per_cpu(xen_callfunc_irq, cpu) >= 0)
 172                 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
 173         if (per_cpu(xen_debug_irq, cpu) >= 0)
 174                 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
 175         if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0)
 176                 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu),
 177                                        NULL);
 178         if (xen_hvm_domain())
 179                 return rc;
 180
 181         if (per_cpu(xen_irq_work, cpu) >= 0)
 182                 unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL);
 183
 184         return rc;
 185 }
 186
 187 static void __init xen_fill_possible_map(void)
 188 {
 189         int i, rc;
 190
 191         if (xen_initial_domain())
 192                 return;
 193
 194         for (i = 0; i < nr_cpu_ids; i++) {
 195                 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
 196                 if (rc >= 0) {
 197                         num_processors++;
 198                         set_cpu_possible(i, true);
 199                 }
 200         }
 201 }
 202
 203 static void __init xen_filter_cpu_maps(void)
 204 {
 205         int i, rc;
 206         unsigned int subtract = 0;
 207
 208         if (!xen_initial_domain())
 209                 return;
 210
 211         num_processors = 0;
 212         disabled_cpus = 0;
 213         for (i = 0; i < nr_cpu_ids; i++) {
 214                 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
 215                 if (rc >= 0) {
 216                         num_processors++;
 217                         set_cpu_possible(i, true);
 218                 } else {
 219                         set_cpu_possible(i, false);
 220                         set_cpu_present(i, false);
 221                         subtract++;
 222                 }
 223         }
 224 #ifdef CONFIG_HOTPLUG_CPU
 225         /* This is akin to using 'nr_cpus' on the Linux command line.
 226          * Which is OK as when we use 'dom0_max_vcpus=X' we can only
 227          * have up to X, while nr_cpu_ids is greater than X. This
 228          * normally is not a problem, except when CPU hotplugging
 229          * is involved and then there might be more than X CPUs
 230          * in the guest - which will not work as there is no
 231          * hypercall to expand the max number of VCPUs an already
 232          * running guest has. So cap it up to X. */
 233         if (subtract)
 234                 nr_cpu_ids = nr_cpu_ids - subtract;
 235 #endif
 236
 237 }
 238
 239 static void __init xen_smp_prepare_boot_cpu(void)
 240 {
 241         BUG_ON(smp_processor_id() != 0);
 242         native_smp_prepare_boot_cpu();
 243
 244         /* We've switched to the "real" per-cpu gdt, so make sure the
 245            old memory can be recycled */
 246         make_lowmem_page_readwrite(xen_initial_gdt);
 247
 248 #ifdef CONFIG_X86_32
 249         /*
 250          * Xen starts us with XEN_FLAT_RING1_DS, but linux code
 251          * expects __USER_DS
 252          */
 253         loadsegment(ds, __USER_DS);
 254         loadsegment(es, __USER_DS);
 255 #endif
 256
 257         xen_filter_cpu_maps();
 258         xen_setup_vcpu_info_placement();
 259 }
 260
 261 static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
 262 {
 263         unsigned cpu;
 264         unsigned int i;
 265
 266         if (skip_ioapic_setup) {
 267                 char *m = (max_cpus == 0) ?
 268                         "The nosmp parameter is incompatible with Xen; " \
 269                         "use Xen dom0_max_vcpus=1 parameter" :
 270                         "The noapic parameter is incompatible with Xen";
 271
 272                 xen_raw_printk(m);
 273                 panic(m);
 274         }
 275         xen_init_lock_cpu(0);
 276
 277         smp_store_boot_cpu_info();
 278         cpu_data(0).x86_max_cores = 1;
 279
 280         for_each_possible_cpu(i) {
 281                 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
 282                 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
 283                 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
 284         }
 285         set_cpu_sibling_map(0);
 286
 287         if (xen_smp_intr_init(0))
 288                 BUG();
 289
 290         if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
 291                 panic("could not allocate xen_cpu_initialized_map\n");
 292
 293         cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
 294
 295         /* Restrict the possible_map according to max_cpus. */
 296         while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
 297                 for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
 298                         continue;
 299                 set_cpu_possible(cpu, false);
 300         }
 301
 302         for_each_possible_cpu(cpu)
 303                 set_cpu_present(cpu, true);
 304 }
 305
 306 static int __cpuinit
 307 cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 308 {
 309         struct vcpu_guest_context *ctxt;
 310         struct desc_struct *gdt;
 311         unsigned long gdt_mfn;
 312
 313         if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
 314                 return 0;
 315
 316         ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
 317         if (ctxt == NULL)
 318                 return -ENOMEM;
 319
 320         gdt = get_cpu_gdt_table(cpu);
 321
 322         ctxt->flags = VGCF_IN_KERNEL;
 323         ctxt->user_regs.ss = __KERNEL_DS;
 324 #ifdef CONFIG_X86_32
 325         ctxt->user_regs.fs = __KERNEL_PERCPU;
 326         ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
 327 #else
 328         ctxt->gs_base_kernel = per_cpu_offset(cpu);
 329 #endif
 330         ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
 331
 332         memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
 333
 334         {
 335                 ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
 336                 ctxt->user_regs.ds = __USER_DS;
 337                 ctxt->user_regs.es = __USER_DS;
 338
 339                 xen_copy_trap_info(ctxt->trap_ctxt);
 340
 341                 ctxt->ldt_ents = 0;
 342
 343                 BUG_ON((unsigned long)gdt & ~PAGE_MASK);
 344
 345                 gdt_mfn = arbitrary_virt_to_mfn(gdt);
 346                 make_lowmem_page_readonly(gdt);
 347                 make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
 348
 349                 ctxt->gdt_frames[0] = gdt_mfn;
 350                 ctxt->gdt_ents      = GDT_ENTRIES;
 351
 352                 ctxt->kernel_ss = __KERNEL_DS;
 353                 ctxt->kernel_sp = idle->thread.sp0;
 354
 355 #ifdef CONFIG_X86_32
 356                 ctxt->event_callback_cs     = __KERNEL_CS;
 357                 ctxt->failsafe_callback_cs  = __KERNEL_CS;
 358 #endif
 359                 ctxt->event_callback_eip    =
 360                                         (unsigned long)xen_hypervisor_callback;
 361                 ctxt->failsafe_callback_eip =
 362                                         (unsigned long)xen_failsafe_callback;
 363         }
 364         ctxt->user_regs.cs = __KERNEL_CS;
 365         ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
 366
 367         per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
 368         ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
 369
 370         if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
 371                 BUG();
 372
 373         kfree(ctxt);
 374         return 0;
 375 }
 376
 377 static int __cpuinit xen_cpu_up(unsigned int cpu, struct task_struct *idle)
 378 {
 379         int rc;
 380
 381         per_cpu(current_task, cpu) = idle;
 382 #ifdef CONFIG_X86_32
 383         irq_ctx_init(cpu);
 384 #else
 385         clear_tsk_thread_flag(idle, TIF_FORK);
 386         per_cpu(kernel_stack, cpu) =
 387                 (unsigned long)task_stack_page(idle) -
 388                 KERNEL_STACK_OFFSET + THREAD_SIZE;
 389 #endif
 390         xen_setup_runstate_info(cpu);
 391         xen_setup_timer(cpu);
 392         xen_init_lock_cpu(cpu);
 393
 394         per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
 395
 396         /* make sure interrupts start blocked */
 397         per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
 398
 399         rc = cpu_initialize_context(cpu, idle);
 400         if (rc)
 401                 return rc;
 402
 403         if (num_online_cpus() == 1)
 404                 /* Just in case we booted with a single CPU. */
 405                 alternatives_enable_smp();
 406
 407         rc = xen_smp_intr_init(cpu);
 408         if (rc)
 409                 return rc;
 410
 411         rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
 412         BUG_ON(rc);
 413
 414         while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
 415                 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
 416                 barrier();
 417         }
 418
 419         return 0;
 420 }
 421
 422 static void xen_smp_cpus_done(unsigned int max_cpus)
 423 {
 424 }
 425
 426 #ifdef CONFIG_HOTPLUG_CPU
 427 static int xen_cpu_disable(void)
 428 {
 429         unsigned int cpu = smp_processor_id();
 430         if (cpu == 0)
 431                 return -EBUSY;
 432
 433         cpu_disable_common();
 434
 435         load_cr3(swapper_pg_dir);
 436         return 0;
 437 }
 438
 439 static void xen_cpu_die(unsigned int cpu)
 440 {
 441         while (xen_pv_domain() && HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
 442                 current->state = TASK_UNINTERRUPTIBLE;
 443                 schedule_timeout(HZ/10);
 444         }
 445         unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
 446         unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
 447         unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
 448         unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
 449         if (!xen_hvm_domain())
 450                 unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL);
 451         xen_uninit_lock_cpu(cpu);
 452         xen_teardown_timer(cpu);
 453 }
 454
 455 static void __cpuinit xen_play_dead(void) /* used only with HOTPLUG_CPU */
 456 {
 457         play_dead_common();
 458         HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
 459         cpu_bringup();
 460         /*
 461          * commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down)
 462          * clears certain data that the cpu_idle loop (which called us
 463          * and that we return from) expects. The only way to get that
 464          * data back is to call:
 465          */
 466         tick_nohz_idle_enter();
 467 }
 468
 469 #else /* !CONFIG_HOTPLUG_CPU */
 470 static int xen_cpu_disable(void)
 471 {
 472         return -ENOSYS;
 473 }
 474
 475 static void xen_cpu_die(unsigned int cpu)
 476 {
 477         BUG();
 478 }
 479
 480 static void xen_play_dead(void)
 481 {
 482         BUG();
 483 }
 484
 485 #endif
 486 static void stop_self(void *v)
 487 {
 488         int cpu = smp_processor_id();
 489
 490         /* make sure we're not pinning something down */
 491         load_cr3(swapper_pg_dir);
 492         /* should set up a minimal gdt */
 493
 494         set_cpu_online(cpu, false);
 495
 496         HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
 497         BUG();
 498 }
 499
 500 static void xen_stop_other_cpus(int wait)
 501 {
 502         smp_call_function(stop_self, NULL, wait);
 503 }
 504
 505 static void xen_smp_send_reschedule(int cpu)
 506 {
 507         xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
 508 }
 509
 510 static void __xen_send_IPI_mask(const struct cpumask *mask,
 511                               int vector)
 512 {
 513         unsigned cpu;
 514
 515         for_each_cpu_and(cpu, mask, cpu_online_mask)
 516                 xen_send_IPI_one(cpu, vector);
 517 }
 518
 519 static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
 520 {
 521         int cpu;
 522
 523         __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
 524
 525         /* Make sure other vcpus get a chance to run if they need to. */
 526         for_each_cpu(cpu, mask) {
 527                 if (xen_vcpu_stolen(cpu)) {
 528                         HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
 529                         break;
 530                 }
 531         }
 532 }
 533
 534 static void xen_smp_send_call_function_single_ipi(int cpu)
 535 {
 536         __xen_send_IPI_mask(cpumask_of(cpu),
 537                           XEN_CALL_FUNCTION_SINGLE_VECTOR);
 538 }
 539
 540 static inline int xen_map_vector(int vector)
 541 {
 542         int xen_vector;
 543
 544         switch (vector) {
 545         case RESCHEDULE_VECTOR:
 546                 xen_vector = XEN_RESCHEDULE_VECTOR;
 547                 break;
 548         case CALL_FUNCTION_VECTOR:
 549                 xen_vector = XEN_CALL_FUNCTION_VECTOR;
 550                 break;
 551         case CALL_FUNCTION_SINGLE_VECTOR:
 552                 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
 553                 break;
 554         case IRQ_WORK_VECTOR:
 555                 xen_vector = XEN_IRQ_WORK_VECTOR;
 556                 break;
 557         default:
 558                 xen_vector = -1;
 559                 printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
 560                         vector);
 561         }
 562
 563         return xen_vector;
 564 }
 565
 566 void xen_send_IPI_mask(const struct cpumask *mask,
 567                               int vector)
 568 {
 569         int xen_vector = xen_map_vector(vector);
 570
 571         if (xen_vector >= 0)
 572                 __xen_send_IPI_mask(mask, xen_vector);
 573 }
 574
 575 void xen_send_IPI_all(int vector)
 576 {
 577         int xen_vector = xen_map_vector(vector);
 578
 579         if (xen_vector >= 0)
 580                 __xen_send_IPI_mask(cpu_online_mask, xen_vector);
 581 }
 582
 583 void xen_send_IPI_self(int vector)
 584 {
 585         int xen_vector = xen_map_vector(vector);
 586
 587         if (xen_vector >= 0)
 588                 xen_send_IPI_one(smp_processor_id(), xen_vector);
 589 }
 590
 591 void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
 592                                 int vector)
 593 {
 594         unsigned cpu;
 595         unsigned int this_cpu = smp_processor_id();
 596         int xen_vector = xen_map_vector(vector);
 597
 598         if (!(num_online_cpus() > 1) || (xen_vector < 0))
 599                 return;
 600
 601         for_each_cpu_and(cpu, mask, cpu_online_mask) {
 602                 if (this_cpu == cpu)
 603                         continue;
 604
 605                 xen_send_IPI_one(cpu, xen_vector);
 606         }
 607 }
 608
 609 void xen_send_IPI_allbutself(int vector)
 610 {
 611         xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
 612 }
 613
 614 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
 615 {
 616         irq_enter();
 617         generic_smp_call_function_interrupt();
 618         inc_irq_stat(irq_call_count);
 619         irq_exit();
 620
 621         return IRQ_HANDLED;
 622 }
 623
 624 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
 625 {
 626         irq_enter();
 627         generic_smp_call_function_single_interrupt();
 628         inc_irq_stat(irq_call_count);
 629         irq_exit();
 630
 631         return IRQ_HANDLED;
 632 }
 633
 634 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
 635 {
 636         irq_enter();
 637         irq_work_run();
 638         inc_irq_stat(apic_irq_work_irqs);
 639         irq_exit();
 640
 641         return IRQ_HANDLED;
 642 }
 643
 644 static const struct smp_ops xen_smp_ops __initconst = {
 645         .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
 646         .smp_prepare_cpus = xen_smp_prepare_cpus,
 647         .smp_cpus_done = xen_smp_cpus_done,
 648
 649         .cpu_up = xen_cpu_up,
 650         .cpu_die = xen_cpu_die,
 651         .cpu_disable = xen_cpu_disable,
 652         .play_dead = xen_play_dead,
 653
 654         .stop_other_cpus = xen_stop_other_cpus,
 655         .smp_send_reschedule = xen_smp_send_reschedule,
 656
 657         .send_call_func_ipi = xen_smp_send_call_function_ipi,
 658         .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
 659 };
 660
 661 void __init xen_smp_init(void)
 662 {
 663         smp_ops = xen_smp_ops;
 664         xen_fill_possible_map();
 665         xen_init_spinlocks();
 666 }
 667
 668 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
 669 {
 670         native_smp_prepare_cpus(max_cpus);
 671         WARN_ON(xen_smp_intr_init(0));
 672
 673         xen_init_lock_cpu(0);
 674 }
 675
 676 static int __cpuinit xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
 677 {
 678         int rc;
 679         /*
 680          * xen_smp_intr_init() needs to run before native_cpu_up()
 681          * so that IPI vectors are set up on the booting CPU before
 682          * it is marked online in native_cpu_up().
 683         */
 684         rc = xen_smp_intr_init(cpu);
 685         WARN_ON(rc);
 686         if (!rc)
 687                 rc =  native_cpu_up(cpu, tidle);
 688         return rc;
 689 }
 690
 691 static void xen_hvm_cpu_die(unsigned int cpu)
 692 {
 693         xen_cpu_die(cpu);
 694         native_cpu_die(cpu);
 695 }
 696
 697 void __init xen_hvm_smp_init(void)
 698 {
 699         if (!xen_have_vector_callback)
 700                 return;
 701         smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
 702         smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
 703         smp_ops.cpu_up = xen_hvm_cpu_up;
 704         smp_ops.cpu_die = xen_hvm_cpu_die;
 705         smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
 706         smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
 707 }