1// SPDX-License-Identifier: GPL-2.0
2#include <linux/smp.h>
3#include <linux/cpu.h>
4#include <linux/slab.h>
5#include <linux/cpumask.h>
6#include <linux/percpu.h>
7
8#include <xen/events.h>
9
10#include <xen/hvc-console.h>
11#include "xen-ops.h"
12
13static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
14static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
15static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
16static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
17
18static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
19static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
20
21/*
22 * Reschedule call back.
23 */
24static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
25{
26 inc_irq_stat(irq_resched_count);
27 scheduler_ipi();
28
29 return IRQ_HANDLED;
30}
31
32void xen_smp_intr_free(unsigned int cpu)
33{
34 kfree(per_cpu(xen_resched_irq, cpu).name);
35 per_cpu(xen_resched_irq, cpu).name = NULL;
36 if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
37 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
38 per_cpu(xen_resched_irq, cpu).irq = -1;
39 }
40 kfree(per_cpu(xen_callfunc_irq, cpu).name);
41 per_cpu(xen_callfunc_irq, cpu).name = NULL;
42 if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
43 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
44 per_cpu(xen_callfunc_irq, cpu).irq = -1;
45 }
46 kfree(per_cpu(xen_debug_irq, cpu).name);
47 per_cpu(xen_debug_irq, cpu).name = NULL;
48 if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
49 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
50 per_cpu(xen_debug_irq, cpu).irq = -1;
51 }
52 kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
53 per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
54 if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
55 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
56 NULL);
57 per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
58 }
59}
60
61int xen_smp_intr_init(unsigned int cpu)
62{
63 int rc;
64 char *resched_name, *callfunc_name, *debug_name;
65
66 resched_name = kasprintf(GFP_KERNEL, fmt: "resched%d", cpu);
67 if (!resched_name)
68 goto fail_mem;
69 per_cpu(xen_resched_irq, cpu).name = resched_name;
70 rc = bind_ipi_to_irqhandler(ipi: XEN_RESCHEDULE_VECTOR,
71 cpu,
72 handler: xen_reschedule_interrupt,
73 IRQF_PERCPU|IRQF_NOBALANCING,
74 devname: resched_name,
75 NULL);
76 if (rc < 0)
77 goto fail;
78 per_cpu(xen_resched_irq, cpu).irq = rc;
79
80 callfunc_name = kasprintf(GFP_KERNEL, fmt: "callfunc%d", cpu);
81 if (!callfunc_name)
82 goto fail_mem;
83 per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;
84 rc = bind_ipi_to_irqhandler(ipi: XEN_CALL_FUNCTION_VECTOR,
85 cpu,
86 handler: xen_call_function_interrupt,
87 IRQF_PERCPU|IRQF_NOBALANCING,
88 devname: callfunc_name,
89 NULL);
90 if (rc < 0)
91 goto fail;
92 per_cpu(xen_callfunc_irq, cpu).irq = rc;
93
94 if (!xen_fifo_events) {
95 debug_name = kasprintf(GFP_KERNEL, fmt: "debug%d", cpu);
96 if (!debug_name)
97 goto fail_mem;
98
99 per_cpu(xen_debug_irq, cpu).name = debug_name;
100 rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu,
101 handler: xen_debug_interrupt,
102 IRQF_PERCPU | IRQF_NOBALANCING,
103 devname: debug_name, NULL);
104 if (rc < 0)
105 goto fail;
106 per_cpu(xen_debug_irq, cpu).irq = rc;
107 }
108
109 callfunc_name = kasprintf(GFP_KERNEL, fmt: "callfuncsingle%d", cpu);
110 if (!callfunc_name)
111 goto fail_mem;
112
113 per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
114 rc = bind_ipi_to_irqhandler(ipi: XEN_CALL_FUNCTION_SINGLE_VECTOR,
115 cpu,
116 handler: xen_call_function_single_interrupt,
117 IRQF_PERCPU|IRQF_NOBALANCING,
118 devname: callfunc_name,
119 NULL);
120 if (rc < 0)
121 goto fail;
122 per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
123
124 return 0;
125
126 fail_mem:
127 rc = -ENOMEM;
128 fail:
129 xen_smp_intr_free(cpu);
130 return rc;
131}
132
133void __init xen_smp_cpus_done(unsigned int max_cpus)
134{
135 if (xen_hvm_domain())
136 native_smp_cpus_done(max_cpus);
137}
138
139void xen_smp_send_reschedule(int cpu)
140{
141 xen_send_IPI_one(cpu, vector: XEN_RESCHEDULE_VECTOR);
142}
143
144static void __xen_send_IPI_mask(const struct cpumask *mask,
145 int vector)
146{
147 unsigned cpu;
148
149 for_each_cpu_and(cpu, mask, cpu_online_mask)
150 xen_send_IPI_one(cpu, vector);
151}
152
153void xen_smp_send_call_function_ipi(const struct cpumask *mask)
154{
155 int cpu;
156
157 __xen_send_IPI_mask(mask, vector: XEN_CALL_FUNCTION_VECTOR);
158
159 /* Make sure other vcpus get a chance to run if they need to. */
160 for_each_cpu(cpu, mask) {
161 if (xen_vcpu_stolen(vcpu: cpu)) {
162 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
163 break;
164 }
165 }
166}
167
168void xen_smp_send_call_function_single_ipi(int cpu)
169{
170 __xen_send_IPI_mask(cpumask_of(cpu),
171 vector: XEN_CALL_FUNCTION_SINGLE_VECTOR);
172}
173
174static inline int xen_map_vector(int vector)
175{
176 int xen_vector;
177
178 switch (vector) {
179 case RESCHEDULE_VECTOR:
180 xen_vector = XEN_RESCHEDULE_VECTOR;
181 break;
182 case CALL_FUNCTION_VECTOR:
183 xen_vector = XEN_CALL_FUNCTION_VECTOR;
184 break;
185 case CALL_FUNCTION_SINGLE_VECTOR:
186 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
187 break;
188 case IRQ_WORK_VECTOR:
189 xen_vector = XEN_IRQ_WORK_VECTOR;
190 break;
191#ifdef CONFIG_X86_64
192 case NMI_VECTOR:
193 case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
194 xen_vector = XEN_NMI_VECTOR;
195 break;
196#endif
197 default:
198 xen_vector = -1;
199 printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
200 vector);
201 }
202
203 return xen_vector;
204}
205
206void xen_send_IPI_mask(const struct cpumask *mask,
207 int vector)
208{
209 int xen_vector = xen_map_vector(vector);
210
211 if (xen_vector >= 0)
212 __xen_send_IPI_mask(mask, vector: xen_vector);
213}
214
215void xen_send_IPI_all(int vector)
216{
217 int xen_vector = xen_map_vector(vector);
218
219 if (xen_vector >= 0)
220 __xen_send_IPI_mask(cpu_online_mask, vector: xen_vector);
221}
222
223void xen_send_IPI_self(int vector)
224{
225 int xen_vector = xen_map_vector(vector);
226
227 if (xen_vector >= 0)
228 xen_send_IPI_one(smp_processor_id(), vector: xen_vector);
229}
230
231void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
232 int vector)
233{
234 unsigned cpu;
235 unsigned int this_cpu = smp_processor_id();
236 int xen_vector = xen_map_vector(vector);
237
238 if (!(num_online_cpus() > 1) || (xen_vector < 0))
239 return;
240
241 for_each_cpu_and(cpu, mask, cpu_online_mask) {
242 if (this_cpu == cpu)
243 continue;
244
245 xen_send_IPI_one(cpu, vector: xen_vector);
246 }
247}
248
249void xen_send_IPI_allbutself(int vector)
250{
251 xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
252}
253
254static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
255{
256 generic_smp_call_function_interrupt();
257 inc_irq_stat(irq_call_count);
258
259 return IRQ_HANDLED;
260}
261
262static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
263{
264 generic_smp_call_function_single_interrupt();
265 inc_irq_stat(irq_call_count);
266
267 return IRQ_HANDLED;
268}
269

source code of linux/arch/x86/xen/smp.c