xref: /openbmc/linux/arch/x86/xen/smp_hvm.c (revision 2cf1c348)
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 }
87