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 #include <xen/interface/xenpmu.h> 30 31 #include <asm/xen/interface.h> 32 #include <asm/xen/hypercall.h> 33 34 #include <xen/xen.h> 35 #include <xen/page.h> 36 #include <xen/events.h> 37 38 #include <xen/hvc-console.h> 39 #include "xen-ops.h" 40 #include "mmu.h" 41 #include "smp.h" 42 #include "pmu.h" 43 44 cpumask_var_t xen_cpu_initialized_map; 45 46 struct xen_common_irq { 47 int irq; 48 char *name; 49 }; 50 static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 }; 51 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 }; 52 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 }; 53 static DEFINE_PER_CPU(struct xen_common_irq, xen_irq_work) = { .irq = -1 }; 54 static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 }; 55 static DEFINE_PER_CPU(struct xen_common_irq, xen_pmu_irq) = { .irq = -1 }; 56 57 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id); 58 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id); 59 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id); 60 61 /* 62 * Reschedule call back. 63 */ 64 static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id) 65 { 66 inc_irq_stat(irq_resched_count); 67 scheduler_ipi(); 68 69 return IRQ_HANDLED; 70 } 71 72 static void cpu_bringup(void) 73 { 74 int cpu; 75 76 cpu_init(); 77 touch_softlockup_watchdog(); 78 preempt_disable(); 79 80 /* PVH runs in ring 0 and allows us to do native syscalls. Yay! */ 81 if (!xen_feature(XENFEAT_supervisor_mode_kernel)) { 82 xen_enable_sysenter(); 83 xen_enable_syscall(); 84 } 85 cpu = smp_processor_id(); 86 smp_store_cpu_info(cpu); 87 cpu_data(cpu).x86_max_cores = 1; 88 set_cpu_sibling_map(cpu); 89 90 xen_setup_cpu_clockevents(); 91 92 notify_cpu_starting(cpu); 93 94 set_cpu_online(cpu, true); 95 96 cpu_set_state_online(cpu); /* Implies full memory barrier. */ 97 98 /* We can take interrupts now: we're officially "up". */ 99 local_irq_enable(); 100 } 101 102 /* 103 * Note: cpu parameter is only relevant for PVH. The reason for passing it 104 * is we can't do smp_processor_id until the percpu segments are loaded, for 105 * which we need the cpu number! So we pass it in rdi as first parameter. 106 */ 107 asmlinkage __visible void cpu_bringup_and_idle(int cpu) 108 { 109 #ifdef CONFIG_XEN_PVH 110 if (xen_feature(XENFEAT_auto_translated_physmap) && 111 xen_feature(XENFEAT_supervisor_mode_kernel)) 112 xen_pvh_secondary_vcpu_init(cpu); 113 #endif 114 cpu_bringup(); 115 cpu_startup_entry(CPUHP_ONLINE); 116 } 117 118 static void xen_smp_intr_free(unsigned int cpu) 119 { 120 if (per_cpu(xen_resched_irq, cpu).irq >= 0) { 121 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL); 122 per_cpu(xen_resched_irq, cpu).irq = -1; 123 kfree(per_cpu(xen_resched_irq, cpu).name); 124 per_cpu(xen_resched_irq, cpu).name = NULL; 125 } 126 if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) { 127 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL); 128 per_cpu(xen_callfunc_irq, cpu).irq = -1; 129 kfree(per_cpu(xen_callfunc_irq, cpu).name); 130 per_cpu(xen_callfunc_irq, cpu).name = NULL; 131 } 132 if (per_cpu(xen_debug_irq, cpu).irq >= 0) { 133 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL); 134 per_cpu(xen_debug_irq, cpu).irq = -1; 135 kfree(per_cpu(xen_debug_irq, cpu).name); 136 per_cpu(xen_debug_irq, cpu).name = NULL; 137 } 138 if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) { 139 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq, 140 NULL); 141 per_cpu(xen_callfuncsingle_irq, cpu).irq = -1; 142 kfree(per_cpu(xen_callfuncsingle_irq, cpu).name); 143 per_cpu(xen_callfuncsingle_irq, cpu).name = NULL; 144 } 145 if (xen_hvm_domain()) 146 return; 147 148 if (per_cpu(xen_irq_work, cpu).irq >= 0) { 149 unbind_from_irqhandler(per_cpu(xen_irq_work, cpu).irq, NULL); 150 per_cpu(xen_irq_work, cpu).irq = -1; 151 kfree(per_cpu(xen_irq_work, cpu).name); 152 per_cpu(xen_irq_work, cpu).name = NULL; 153 } 154 155 if (per_cpu(xen_pmu_irq, cpu).irq >= 0) { 156 unbind_from_irqhandler(per_cpu(xen_pmu_irq, cpu).irq, NULL); 157 per_cpu(xen_pmu_irq, cpu).irq = -1; 158 kfree(per_cpu(xen_pmu_irq, cpu).name); 159 per_cpu(xen_pmu_irq, cpu).name = NULL; 160 } 161 }; 162 static int xen_smp_intr_init(unsigned int cpu) 163 { 164 int rc; 165 char *resched_name, *callfunc_name, *debug_name, *pmu_name; 166 167 resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu); 168 rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, 169 cpu, 170 xen_reschedule_interrupt, 171 IRQF_PERCPU|IRQF_NOBALANCING, 172 resched_name, 173 NULL); 174 if (rc < 0) 175 goto fail; 176 per_cpu(xen_resched_irq, cpu).irq = rc; 177 per_cpu(xen_resched_irq, cpu).name = resched_name; 178 179 callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu); 180 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR, 181 cpu, 182 xen_call_function_interrupt, 183 IRQF_PERCPU|IRQF_NOBALANCING, 184 callfunc_name, 185 NULL); 186 if (rc < 0) 187 goto fail; 188 per_cpu(xen_callfunc_irq, cpu).irq = rc; 189 per_cpu(xen_callfunc_irq, cpu).name = callfunc_name; 190 191 debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu); 192 rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt, 193 IRQF_PERCPU | IRQF_NOBALANCING, 194 debug_name, NULL); 195 if (rc < 0) 196 goto fail; 197 per_cpu(xen_debug_irq, cpu).irq = rc; 198 per_cpu(xen_debug_irq, cpu).name = debug_name; 199 200 callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu); 201 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR, 202 cpu, 203 xen_call_function_single_interrupt, 204 IRQF_PERCPU|IRQF_NOBALANCING, 205 callfunc_name, 206 NULL); 207 if (rc < 0) 208 goto fail; 209 per_cpu(xen_callfuncsingle_irq, cpu).irq = rc; 210 per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name; 211 212 /* 213 * The IRQ worker on PVHVM goes through the native path and uses the 214 * IPI mechanism. 215 */ 216 if (xen_hvm_domain()) 217 return 0; 218 219 callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu); 220 rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR, 221 cpu, 222 xen_irq_work_interrupt, 223 IRQF_PERCPU|IRQF_NOBALANCING, 224 callfunc_name, 225 NULL); 226 if (rc < 0) 227 goto fail; 228 per_cpu(xen_irq_work, cpu).irq = rc; 229 per_cpu(xen_irq_work, cpu).name = callfunc_name; 230 231 if (is_xen_pmu(cpu)) { 232 pmu_name = kasprintf(GFP_KERNEL, "pmu%d", cpu); 233 rc = bind_virq_to_irqhandler(VIRQ_XENPMU, cpu, 234 xen_pmu_irq_handler, 235 IRQF_PERCPU|IRQF_NOBALANCING, 236 pmu_name, NULL); 237 if (rc < 0) 238 goto fail; 239 per_cpu(xen_pmu_irq, cpu).irq = rc; 240 per_cpu(xen_pmu_irq, cpu).name = pmu_name; 241 } 242 243 return 0; 244 245 fail: 246 xen_smp_intr_free(cpu); 247 return rc; 248 } 249 250 static void __init xen_fill_possible_map(void) 251 { 252 int i, rc; 253 254 if (xen_initial_domain()) 255 return; 256 257 for (i = 0; i < nr_cpu_ids; i++) { 258 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL); 259 if (rc >= 0) { 260 num_processors++; 261 set_cpu_possible(i, true); 262 } 263 } 264 } 265 266 static void __init xen_filter_cpu_maps(void) 267 { 268 int i, rc; 269 unsigned int subtract = 0; 270 271 if (!xen_initial_domain()) 272 return; 273 274 num_processors = 0; 275 disabled_cpus = 0; 276 for (i = 0; i < nr_cpu_ids; i++) { 277 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL); 278 if (rc >= 0) { 279 num_processors++; 280 set_cpu_possible(i, true); 281 } else { 282 set_cpu_possible(i, false); 283 set_cpu_present(i, false); 284 subtract++; 285 } 286 } 287 #ifdef CONFIG_HOTPLUG_CPU 288 /* This is akin to using 'nr_cpus' on the Linux command line. 289 * Which is OK as when we use 'dom0_max_vcpus=X' we can only 290 * have up to X, while nr_cpu_ids is greater than X. This 291 * normally is not a problem, except when CPU hotplugging 292 * is involved and then there might be more than X CPUs 293 * in the guest - which will not work as there is no 294 * hypercall to expand the max number of VCPUs an already 295 * running guest has. So cap it up to X. */ 296 if (subtract) 297 nr_cpu_ids = nr_cpu_ids - subtract; 298 #endif 299 300 } 301 302 static void __init xen_smp_prepare_boot_cpu(void) 303 { 304 BUG_ON(smp_processor_id() != 0); 305 native_smp_prepare_boot_cpu(); 306 307 if (xen_pv_domain()) { 308 if (!xen_feature(XENFEAT_writable_page_tables)) 309 /* We've switched to the "real" per-cpu gdt, so make 310 * sure the old memory can be recycled. */ 311 make_lowmem_page_readwrite(xen_initial_gdt); 312 313 #ifdef CONFIG_X86_32 314 /* 315 * Xen starts us with XEN_FLAT_RING1_DS, but linux code 316 * expects __USER_DS 317 */ 318 loadsegment(ds, __USER_DS); 319 loadsegment(es, __USER_DS); 320 #endif 321 322 xen_filter_cpu_maps(); 323 xen_setup_vcpu_info_placement(); 324 } 325 /* 326 * The alternative logic (which patches the unlock/lock) runs before 327 * the smp bootup up code is activated. Hence we need to set this up 328 * the core kernel is being patched. Otherwise we will have only 329 * modules patched but not core code. 330 */ 331 xen_init_spinlocks(); 332 } 333 334 static void __init xen_smp_prepare_cpus(unsigned int max_cpus) 335 { 336 unsigned cpu; 337 unsigned int i; 338 339 if (skip_ioapic_setup) { 340 char *m = (max_cpus == 0) ? 341 "The nosmp parameter is incompatible with Xen; " \ 342 "use Xen dom0_max_vcpus=1 parameter" : 343 "The noapic parameter is incompatible with Xen"; 344 345 xen_raw_printk(m); 346 panic(m); 347 } 348 xen_init_lock_cpu(0); 349 350 smp_store_boot_cpu_info(); 351 cpu_data(0).x86_max_cores = 1; 352 353 for_each_possible_cpu(i) { 354 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL); 355 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL); 356 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL); 357 } 358 set_cpu_sibling_map(0); 359 360 xen_pmu_init(0); 361 362 if (xen_smp_intr_init(0)) 363 BUG(); 364 365 if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL)) 366 panic("could not allocate xen_cpu_initialized_map\n"); 367 368 cpumask_copy(xen_cpu_initialized_map, cpumask_of(0)); 369 370 /* Restrict the possible_map according to max_cpus. */ 371 while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) { 372 for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--) 373 continue; 374 set_cpu_possible(cpu, false); 375 } 376 377 for_each_possible_cpu(cpu) 378 set_cpu_present(cpu, true); 379 } 380 381 static int 382 cpu_initialize_context(unsigned int cpu, struct task_struct *idle) 383 { 384 struct vcpu_guest_context *ctxt; 385 struct desc_struct *gdt; 386 unsigned long gdt_mfn; 387 388 /* used to tell cpu_init() that it can proceed with initialization */ 389 cpumask_set_cpu(cpu, cpu_callout_mask); 390 if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map)) 391 return 0; 392 393 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL); 394 if (ctxt == NULL) 395 return -ENOMEM; 396 397 gdt = get_cpu_gdt_table(cpu); 398 399 #ifdef CONFIG_X86_32 400 /* Note: PVH is not yet supported on x86_32. */ 401 ctxt->user_regs.fs = __KERNEL_PERCPU; 402 ctxt->user_regs.gs = __KERNEL_STACK_CANARY; 403 #endif 404 memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt)); 405 406 if (!xen_feature(XENFEAT_auto_translated_physmap)) { 407 ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle; 408 ctxt->flags = VGCF_IN_KERNEL; 409 ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */ 410 ctxt->user_regs.ds = __USER_DS; 411 ctxt->user_regs.es = __USER_DS; 412 ctxt->user_regs.ss = __KERNEL_DS; 413 414 xen_copy_trap_info(ctxt->trap_ctxt); 415 416 ctxt->ldt_ents = 0; 417 418 BUG_ON((unsigned long)gdt & ~PAGE_MASK); 419 420 gdt_mfn = arbitrary_virt_to_mfn(gdt); 421 make_lowmem_page_readonly(gdt); 422 make_lowmem_page_readonly(mfn_to_virt(gdt_mfn)); 423 424 ctxt->gdt_frames[0] = gdt_mfn; 425 ctxt->gdt_ents = GDT_ENTRIES; 426 427 ctxt->kernel_ss = __KERNEL_DS; 428 ctxt->kernel_sp = idle->thread.sp0; 429 430 #ifdef CONFIG_X86_32 431 ctxt->event_callback_cs = __KERNEL_CS; 432 ctxt->failsafe_callback_cs = __KERNEL_CS; 433 #else 434 ctxt->gs_base_kernel = per_cpu_offset(cpu); 435 #endif 436 ctxt->event_callback_eip = 437 (unsigned long)xen_hypervisor_callback; 438 ctxt->failsafe_callback_eip = 439 (unsigned long)xen_failsafe_callback; 440 ctxt->user_regs.cs = __KERNEL_CS; 441 per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir); 442 } 443 #ifdef CONFIG_XEN_PVH 444 else { 445 /* 446 * The vcpu comes on kernel page tables which have the NX pte 447 * bit set. This means before DS/SS is touched, NX in 448 * EFER must be set. Hence the following assembly glue code. 449 */ 450 ctxt->user_regs.eip = (unsigned long)xen_pvh_early_cpu_init; 451 ctxt->user_regs.rdi = cpu; 452 ctxt->user_regs.rsi = true; /* entry == true */ 453 } 454 #endif 455 ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs); 456 ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_gfn(swapper_pg_dir)); 457 if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt)) 458 BUG(); 459 460 kfree(ctxt); 461 return 0; 462 } 463 464 static int xen_cpu_up(unsigned int cpu, struct task_struct *idle) 465 { 466 int rc; 467 468 common_cpu_up(cpu, idle); 469 470 xen_setup_runstate_info(cpu); 471 xen_setup_timer(cpu); 472 xen_init_lock_cpu(cpu); 473 474 /* 475 * PV VCPUs are always successfully taken down (see 'while' loop 476 * in xen_cpu_die()), so -EBUSY is an error. 477 */ 478 rc = cpu_check_up_prepare(cpu); 479 if (rc) 480 return rc; 481 482 /* make sure interrupts start blocked */ 483 per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1; 484 485 rc = cpu_initialize_context(cpu, idle); 486 if (rc) 487 return rc; 488 489 xen_pmu_init(cpu); 490 491 rc = xen_smp_intr_init(cpu); 492 if (rc) 493 return rc; 494 495 rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL); 496 BUG_ON(rc); 497 498 while (cpu_report_state(cpu) != CPU_ONLINE) 499 HYPERVISOR_sched_op(SCHEDOP_yield, NULL); 500 501 return 0; 502 } 503 504 static void xen_smp_cpus_done(unsigned int max_cpus) 505 { 506 } 507 508 #ifdef CONFIG_HOTPLUG_CPU 509 static int xen_cpu_disable(void) 510 { 511 unsigned int cpu = smp_processor_id(); 512 if (cpu == 0) 513 return -EBUSY; 514 515 cpu_disable_common(); 516 517 load_cr3(swapper_pg_dir); 518 return 0; 519 } 520 521 static void xen_cpu_die(unsigned int cpu) 522 { 523 while (xen_pv_domain() && HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) { 524 __set_current_state(TASK_UNINTERRUPTIBLE); 525 schedule_timeout(HZ/10); 526 } 527 528 if (common_cpu_die(cpu) == 0) { 529 xen_smp_intr_free(cpu); 530 xen_uninit_lock_cpu(cpu); 531 xen_teardown_timer(cpu); 532 xen_pmu_finish(cpu); 533 } 534 } 535 536 static void xen_play_dead(void) /* used only with HOTPLUG_CPU */ 537 { 538 play_dead_common(); 539 HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL); 540 cpu_bringup(); 541 /* 542 * commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down) 543 * clears certain data that the cpu_idle loop (which called us 544 * and that we return from) expects. The only way to get that 545 * data back is to call: 546 */ 547 tick_nohz_idle_enter(); 548 } 549 550 #else /* !CONFIG_HOTPLUG_CPU */ 551 static int xen_cpu_disable(void) 552 { 553 return -ENOSYS; 554 } 555 556 static void xen_cpu_die(unsigned int cpu) 557 { 558 BUG(); 559 } 560 561 static void xen_play_dead(void) 562 { 563 BUG(); 564 } 565 566 #endif 567 static void stop_self(void *v) 568 { 569 int cpu = smp_processor_id(); 570 571 /* make sure we're not pinning something down */ 572 load_cr3(swapper_pg_dir); 573 /* should set up a minimal gdt */ 574 575 set_cpu_online(cpu, false); 576 577 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL); 578 BUG(); 579 } 580 581 static void xen_stop_other_cpus(int wait) 582 { 583 smp_call_function(stop_self, NULL, wait); 584 } 585 586 static void xen_smp_send_reschedule(int cpu) 587 { 588 xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR); 589 } 590 591 static void __xen_send_IPI_mask(const struct cpumask *mask, 592 int vector) 593 { 594 unsigned cpu; 595 596 for_each_cpu_and(cpu, mask, cpu_online_mask) 597 xen_send_IPI_one(cpu, vector); 598 } 599 600 static void xen_smp_send_call_function_ipi(const struct cpumask *mask) 601 { 602 int cpu; 603 604 __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR); 605 606 /* Make sure other vcpus get a chance to run if they need to. */ 607 for_each_cpu(cpu, mask) { 608 if (xen_vcpu_stolen(cpu)) { 609 HYPERVISOR_sched_op(SCHEDOP_yield, NULL); 610 break; 611 } 612 } 613 } 614 615 static void xen_smp_send_call_function_single_ipi(int cpu) 616 { 617 __xen_send_IPI_mask(cpumask_of(cpu), 618 XEN_CALL_FUNCTION_SINGLE_VECTOR); 619 } 620 621 static inline int xen_map_vector(int vector) 622 { 623 int xen_vector; 624 625 switch (vector) { 626 case RESCHEDULE_VECTOR: 627 xen_vector = XEN_RESCHEDULE_VECTOR; 628 break; 629 case CALL_FUNCTION_VECTOR: 630 xen_vector = XEN_CALL_FUNCTION_VECTOR; 631 break; 632 case CALL_FUNCTION_SINGLE_VECTOR: 633 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR; 634 break; 635 case IRQ_WORK_VECTOR: 636 xen_vector = XEN_IRQ_WORK_VECTOR; 637 break; 638 #ifdef CONFIG_X86_64 639 case NMI_VECTOR: 640 case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */ 641 xen_vector = XEN_NMI_VECTOR; 642 break; 643 #endif 644 default: 645 xen_vector = -1; 646 printk(KERN_ERR "xen: vector 0x%x is not implemented\n", 647 vector); 648 } 649 650 return xen_vector; 651 } 652 653 void xen_send_IPI_mask(const struct cpumask *mask, 654 int vector) 655 { 656 int xen_vector = xen_map_vector(vector); 657 658 if (xen_vector >= 0) 659 __xen_send_IPI_mask(mask, xen_vector); 660 } 661 662 void xen_send_IPI_all(int vector) 663 { 664 int xen_vector = xen_map_vector(vector); 665 666 if (xen_vector >= 0) 667 __xen_send_IPI_mask(cpu_online_mask, xen_vector); 668 } 669 670 void xen_send_IPI_self(int vector) 671 { 672 int xen_vector = xen_map_vector(vector); 673 674 if (xen_vector >= 0) 675 xen_send_IPI_one(smp_processor_id(), xen_vector); 676 } 677 678 void xen_send_IPI_mask_allbutself(const struct cpumask *mask, 679 int vector) 680 { 681 unsigned cpu; 682 unsigned int this_cpu = smp_processor_id(); 683 int xen_vector = xen_map_vector(vector); 684 685 if (!(num_online_cpus() > 1) || (xen_vector < 0)) 686 return; 687 688 for_each_cpu_and(cpu, mask, cpu_online_mask) { 689 if (this_cpu == cpu) 690 continue; 691 692 xen_send_IPI_one(cpu, xen_vector); 693 } 694 } 695 696 void xen_send_IPI_allbutself(int vector) 697 { 698 xen_send_IPI_mask_allbutself(cpu_online_mask, vector); 699 } 700 701 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id) 702 { 703 irq_enter(); 704 generic_smp_call_function_interrupt(); 705 inc_irq_stat(irq_call_count); 706 irq_exit(); 707 708 return IRQ_HANDLED; 709 } 710 711 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id) 712 { 713 irq_enter(); 714 generic_smp_call_function_single_interrupt(); 715 inc_irq_stat(irq_call_count); 716 irq_exit(); 717 718 return IRQ_HANDLED; 719 } 720 721 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id) 722 { 723 irq_enter(); 724 irq_work_run(); 725 inc_irq_stat(apic_irq_work_irqs); 726 irq_exit(); 727 728 return IRQ_HANDLED; 729 } 730 731 static const struct smp_ops xen_smp_ops __initconst = { 732 .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu, 733 .smp_prepare_cpus = xen_smp_prepare_cpus, 734 .smp_cpus_done = xen_smp_cpus_done, 735 736 .cpu_up = xen_cpu_up, 737 .cpu_die = xen_cpu_die, 738 .cpu_disable = xen_cpu_disable, 739 .play_dead = xen_play_dead, 740 741 .stop_other_cpus = xen_stop_other_cpus, 742 .smp_send_reschedule = xen_smp_send_reschedule, 743 744 .send_call_func_ipi = xen_smp_send_call_function_ipi, 745 .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi, 746 }; 747 748 void __init xen_smp_init(void) 749 { 750 smp_ops = xen_smp_ops; 751 xen_fill_possible_map(); 752 } 753 754 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus) 755 { 756 native_smp_prepare_cpus(max_cpus); 757 WARN_ON(xen_smp_intr_init(0)); 758 759 xen_init_lock_cpu(0); 760 } 761 762 static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle) 763 { 764 int rc; 765 766 /* 767 * This can happen if CPU was offlined earlier and 768 * offlining timed out in common_cpu_die(). 769 */ 770 if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) { 771 xen_smp_intr_free(cpu); 772 xen_uninit_lock_cpu(cpu); 773 } 774 775 /* 776 * xen_smp_intr_init() needs to run before native_cpu_up() 777 * so that IPI vectors are set up on the booting CPU before 778 * it is marked online in native_cpu_up(). 779 */ 780 rc = xen_smp_intr_init(cpu); 781 WARN_ON(rc); 782 if (!rc) 783 rc = native_cpu_up(cpu, tidle); 784 785 /* 786 * We must initialize the slowpath CPU kicker _after_ the native 787 * path has executed. If we initialized it before none of the 788 * unlocker IPI kicks would reach the booting CPU as the booting 789 * CPU had not set itself 'online' in cpu_online_mask. That mask 790 * is checked when IPIs are sent (on HVM at least). 791 */ 792 xen_init_lock_cpu(cpu); 793 return rc; 794 } 795 796 void __init xen_hvm_smp_init(void) 797 { 798 if (!xen_have_vector_callback) 799 return; 800 smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus; 801 smp_ops.smp_send_reschedule = xen_smp_send_reschedule; 802 smp_ops.cpu_up = xen_hvm_cpu_up; 803 smp_ops.cpu_die = xen_cpu_die; 804 smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi; 805 smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi; 806 smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu; 807 } 808