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
 9static 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
35static 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
56static 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
65static void xen_hvm_cleanup_dead_cpu(unsigned int cpu)
66{
67	BUG();
68}
69#endif
70
71void __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}