xref: /linux/arch/x86/xen/smp_hvm.c (revision 5dfe7a7e52ccdf60dfd11ccbe509e4365ea721ca)
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 	 * Called again in case the kernel boots on vcpu >= MAX_VIRT_CPUS.
24 	 * Refer to comments in xen_hvm_init_time_ops().
25 	 */
26 	xen_hvm_init_time_ops();
27 
28 	/*
29 	 * The alternative logic (which patches the unlock/lock) runs before
30 	 * the smp bootup up code is activated. Hence we need to set this up
31 	 * the core kernel is being patched. Otherwise we will have only
32 	 * modules patched but not core code.
33 	 */
34 	xen_init_spinlocks();
35 }
36 
37 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
38 {
39 	int cpu;
40 
41 	native_smp_prepare_cpus(max_cpus);
42 
43 	if (xen_have_vector_callback) {
44 		WARN_ON(xen_smp_intr_init(0));
45 		xen_init_lock_cpu(0);
46 	}
47 
48 	for_each_possible_cpu(cpu) {
49 		if (cpu == 0)
50 			continue;
51 
52 		/* Set default vcpu_id to make sure that we don't use cpu-0's */
53 		per_cpu(xen_vcpu_id, cpu) = XEN_VCPU_ID_INVALID;
54 	}
55 }
56 
57 #ifdef CONFIG_HOTPLUG_CPU
58 static void xen_hvm_cleanup_dead_cpu(unsigned int cpu)
59 {
60 	if (xen_have_vector_callback) {
61 		xen_smp_intr_free(cpu);
62 		xen_uninit_lock_cpu(cpu);
63 		xen_teardown_timer(cpu);
64 	}
65 }
66 #else
67 static void xen_hvm_cleanup_dead_cpu(unsigned int cpu)
68 {
69 	BUG();
70 }
71 #endif
72 
73 void __init xen_hvm_smp_init(void)
74 {
75 	smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu;
76 	smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
77 	smp_ops.smp_cpus_done = xen_smp_cpus_done;
78 	smp_ops.cleanup_dead_cpu = xen_hvm_cleanup_dead_cpu;
79 
80 	if (!xen_have_vector_callback) {
81 #ifdef CONFIG_PARAVIRT_SPINLOCKS
82 		nopvspin = true;
83 #endif
84 		return;
85 	}
86 
87 	smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
88 	smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
89 	smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
90 }
91