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
   9 static void __init xen_hvm_smp_prepare_boot_cpu(void)
  10 {
  11         BUG_ON(smp_processor_id() != 0);
  12         native_smp_prepare_boot_cpu();
  13
  14         /*
  15          * Setup vcpu_info for boot CPU. Secondary CPUs get their vcpu_info
  16          * in xen_cpu_up_prepare_hvm().
  17          */
  18         xen_vcpu_setup(0);
  19
  20         /*
  21          * Called again in case the kernel boots on vcpu >= MAX_VIRT_CPUS.
  22          * Refer to comments in xen_hvm_init_time_ops().
  23          */
  24         xen_hvm_init_time_ops();
  25
  26         /*
  27          * The alternative logic (which patches the unlock/lock) runs before
  28          * the smp bootup up code is activated. Hence we need to set this up
  29          * the core kernel is being patched. Otherwise we will have only
  30          * modules patched but not core code.
  31          */
  32         xen_init_spinlocks();
  33 }
  34
  35 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
  36 {
  37         int cpu;
  38
  39         native_smp_prepare_cpus(max_cpus);
  40
  41         if (xen_have_vector_callback) {
  42                 WARN_ON(xen_smp_intr_init(0));
  43                 xen_init_lock_cpu(0);
  44         }
  45
  46         for_each_possible_cpu(cpu) {
  47                 if (cpu == 0)
  48                         continue;
  49
  50                 /* Set default vcpu_id to make sure that we don't use cpu-0's */
  51                 per_cpu(xen_vcpu_id, cpu) = XEN_VCPU_ID_INVALID;
  52         }
  53 }
  54
  55 #ifdef CONFIG_HOTPLUG_CPU
  56 static void xen_hvm_cleanup_dead_cpu(unsigned int cpu)
  57 {
  58         if (xen_have_vector_callback) {
  59                 xen_smp_intr_free(cpu);
  60                 xen_uninit_lock_cpu(cpu);
  61                 xen_teardown_timer(cpu);
  62         }
  63 }
  64 #else
  65 static void xen_hvm_cleanup_dead_cpu(unsigned int cpu)
  66 {
  67         BUG();
  68 }
  69 #endif
  70
  71 void __init xen_hvm_smp_init(void)
  72 {
  73         smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu;
  74         smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
  75         smp_ops.smp_cpus_done = xen_smp_cpus_done;
  76         smp_ops.cleanup_dead_cpu = xen_hvm_cleanup_dead_cpu;
  77
  78         if (!xen_have_vector_callback) {
  79 #ifdef CONFIG_PARAVIRT_SPINLOCKS
  80                 nopvspin = true;
  81 #endif
  82                 return;
  83         }
  84
  85         smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
  86         smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
  87         smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
  88 }