arch/x86/xen/smp_hvm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/thread_info.h>
   3 #include <asm/smp.h>
   4
   5 #include <xen/events.h>
   6
   7 #include "xen-ops.h"
   8 #include "smp.h"
   9
  10
  11 static void __init xen_hvm_smp_prepare_boot_cpu(void)
  12 {
  13         BUG_ON(smp_processor_id() != 0);
  14         native_smp_prepare_boot_cpu();
  15
  16         /*
  17          * Setup vcpu_info for boot CPU. Secondary CPUs get their vcpu_info
  18          * in xen_cpu_up_prepare_hvm().
  19          */
  20         xen_vcpu_setup(0);
  21
  22         /*
  23          * The alternative logic (which patches the unlock/lock) runs before
  24          * the smp bootup up code is activated. Hence we need to set this up
  25          * the core kernel is being patched. Otherwise we will have only
  26          * modules patched but not core code.
  27          */
  28         xen_init_spinlocks();
  29 }
  30
  31 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
  32 {
  33         int cpu;
  34
  35         native_smp_prepare_cpus(max_cpus);
  36
  37         if (xen_have_vector_callback) {
  38                 WARN_ON(xen_smp_intr_init(0));
  39                 xen_init_lock_cpu(0);
  40         }
  41
  42         for_each_possible_cpu(cpu) {
  43                 if (cpu == 0)
  44                         continue;
  45
  46                 /* Set default vcpu_id to make sure that we don't use cpu-0's */
  47                 per_cpu(xen_vcpu_id, cpu) = XEN_VCPU_ID_INVALID;
  48         }
  49 }
  50
  51 #ifdef CONFIG_HOTPLUG_CPU
  52 static void xen_hvm_cpu_die(unsigned int cpu)
  53 {
  54         if (common_cpu_die(cpu) == 0) {
  55                 if (xen_have_vector_callback) {
  56                         xen_smp_intr_free(cpu);
  57                         xen_uninit_lock_cpu(cpu);
  58                         xen_teardown_timer(cpu);
  59                 }
  60         }
  61 }
  62 #else
  63 static void xen_hvm_cpu_die(unsigned int cpu)
  64 {
  65         BUG();
  66 }
  67 #endif
  68
  69 void __init xen_hvm_smp_init(void)
  70 {
  71         smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu;
  72         smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
  73         smp_ops.smp_cpus_done = xen_smp_cpus_done;
  74         smp_ops.cpu_die = xen_hvm_cpu_die;
  75
  76         if (!xen_have_vector_callback) {
  77 #ifdef CONFIG_PARAVIRT_SPINLOCKS
  78                 nopvspin = true;
  79 #endif
  80                 return;
  81         }
  82
  83         smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
  84         smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
  85         smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
  86 }