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#include "smp.h" 13 14static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 }; 15static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 }; 16static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 }; 17static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 }; 18 19static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id); 20static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id); 21 22/* 23 * Reschedule call back. 24 */ 25static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id) 26{ 27 inc_irq_stat(irq_resched_count); 28 scheduler_ipi(); 29 30 return IRQ_HANDLED; 31} 32 33void xen_smp_intr_free(unsigned int cpu) 34{ 35 kfree(per_cpu(xen_resched_irq, cpu).name); 36 per_cpu(xen_resched_irq, cpu).name = NULL; 37 if (per_cpu(xen_resched_irq, cpu).irq >= 0) { 38 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL); 39 per_cpu(xen_resched_irq, cpu).irq = -1; 40 } 41 kfree(per_cpu(xen_callfunc_irq, cpu).name); 42 per_cpu(xen_callfunc_irq, cpu).name = NULL; 43 if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) { 44 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL); 45 per_cpu(xen_callfunc_irq, cpu).irq = -1; 46 } 47 kfree(per_cpu(xen_debug_irq, cpu).name); 48 per_cpu(xen_debug_irq, cpu).name = NULL; 49 if (per_cpu(xen_debug_irq, cpu).irq >= 0) { 50 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL); 51 per_cpu(xen_debug_irq, cpu).irq = -1; 52 } 53 kfree(per_cpu(xen_callfuncsingle_irq, cpu).name); 54 per_cpu(xen_callfuncsingle_irq, cpu).name = NULL; 55 if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) { 56 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq, 57 NULL); 58 per_cpu(xen_callfuncsingle_irq, cpu).irq = -1; 59 } 60} 61 62int xen_smp_intr_init(unsigned int cpu) 63{ 64 int rc; 65 char *resched_name, *callfunc_name, *debug_name; 66 67 resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu); 68 per_cpu(xen_resched_irq, cpu).name = resched_name; 69 rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, 70 cpu, 71 xen_reschedule_interrupt, 72 IRQF_PERCPU|IRQF_NOBALANCING, 73 resched_name, 74 NULL); 75 if (rc < 0) 76 goto fail; 77 per_cpu(xen_resched_irq, cpu).irq = rc; 78 79 callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu); 80 per_cpu(xen_callfunc_irq, cpu).name = callfunc_name; 81 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR, 82 cpu, 83 xen_call_function_interrupt, 84 IRQF_PERCPU|IRQF_NOBALANCING, 85 callfunc_name, 86 NULL); 87 if (rc < 0) 88 goto fail; 89 per_cpu(xen_callfunc_irq, cpu).irq = rc; 90 91 if (!xen_fifo_events) { 92 debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu); 93 per_cpu(xen_debug_irq, cpu).name = debug_name; 94 rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, 95 xen_debug_interrupt, 96 IRQF_PERCPU | IRQF_NOBALANCING, 97 debug_name, NULL); 98 if (rc < 0) 99 goto fail; 100 per_cpu(xen_debug_irq, cpu).irq = rc; 101 } 102 103 callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu); 104 per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name; 105 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR, 106 cpu, 107 xen_call_function_single_interrupt, 108 IRQF_PERCPU|IRQF_NOBALANCING, 109 callfunc_name, 110 NULL); 111 if (rc < 0) 112 goto fail; 113 per_cpu(xen_callfuncsingle_irq, cpu).irq = rc; 114 115 return 0; 116 117 fail: 118 xen_smp_intr_free(cpu); 119 return rc; 120} 121 122void __init xen_smp_cpus_done(unsigned int max_cpus) 123{ 124 int cpu, rc, count = 0; 125 126 if (xen_hvm_domain()) 127 native_smp_cpus_done(max_cpus); 128 else 129 calculate_max_logical_packages(); 130 131 if (xen_have_vcpu_info_placement) 132 return; 133 134 for_each_online_cpu(cpu) { 135 if (xen_vcpu_nr(cpu) < MAX_VIRT_CPUS) 136 continue; 137 138 rc = remove_cpu(cpu); 139 140 if (rc == 0) { 141 /* 142 * Reset vcpu_info so this cpu cannot be onlined again. 143 */ 144 xen_vcpu_info_reset(cpu); 145 count++; 146 } else { 147 pr_warn("%s: failed to bring CPU %d down, error %d\n", 148 __func__, cpu, rc); 149 } 150 } 151 WARN(count, "%s: brought %d CPUs offline\n", __func__, count); 152} 153 154void xen_smp_send_reschedule(int cpu) 155{ 156 xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR); 157} 158 159static void __xen_send_IPI_mask(const struct cpumask *mask, 160 int vector) 161{ 162 unsigned cpu; 163 164 for_each_cpu_and(cpu, mask, cpu_online_mask) 165 xen_send_IPI_one(cpu, vector); 166} 167 168void xen_smp_send_call_function_ipi(const struct cpumask *mask) 169{ 170 int cpu; 171 172 __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR); 173 174 /* Make sure other vcpus get a chance to run if they need to. */ 175 for_each_cpu(cpu, mask) { 176 if (xen_vcpu_stolen(cpu)) { 177 HYPERVISOR_sched_op(SCHEDOP_yield, NULL); 178 break; 179 } 180 } 181} 182 183void xen_smp_send_call_function_single_ipi(int cpu) 184{ 185 __xen_send_IPI_mask(cpumask_of(cpu), 186 XEN_CALL_FUNCTION_SINGLE_VECTOR); 187} 188 189static inline int xen_map_vector(int vector) 190{ 191 int xen_vector; 192 193 switch (vector) { 194 case RESCHEDULE_VECTOR: 195 xen_vector = XEN_RESCHEDULE_VECTOR; 196 break; 197 case CALL_FUNCTION_VECTOR: 198 xen_vector = XEN_CALL_FUNCTION_VECTOR; 199 break; 200 case CALL_FUNCTION_SINGLE_VECTOR: 201 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR; 202 break; 203 case IRQ_WORK_VECTOR: 204 xen_vector = XEN_IRQ_WORK_VECTOR; 205 break; 206#ifdef CONFIG_X86_64 207 case NMI_VECTOR: 208 case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */ 209 xen_vector = XEN_NMI_VECTOR; 210 break; 211#endif 212 default: 213 xen_vector = -1; 214 printk(KERN_ERR "xen: vector 0x%x is not implemented\n", 215 vector); 216 } 217 218 return xen_vector; 219} 220 221void xen_send_IPI_mask(const struct cpumask *mask, 222 int vector) 223{ 224 int xen_vector = xen_map_vector(vector); 225 226 if (xen_vector >= 0) 227 __xen_send_IPI_mask(mask, xen_vector); 228} 229 230void xen_send_IPI_all(int vector) 231{ 232 int xen_vector = xen_map_vector(vector); 233 234 if (xen_vector >= 0) 235 __xen_send_IPI_mask(cpu_online_mask, xen_vector); 236} 237 238void xen_send_IPI_self(int vector) 239{ 240 int xen_vector = xen_map_vector(vector); 241 242 if (xen_vector >= 0) 243 xen_send_IPI_one(smp_processor_id(), xen_vector); 244} 245 246void xen_send_IPI_mask_allbutself(const struct cpumask *mask, 247 int vector) 248{ 249 unsigned cpu; 250 unsigned int this_cpu = smp_processor_id(); 251 int xen_vector = xen_map_vector(vector); 252 253 if (!(num_online_cpus() > 1) || (xen_vector < 0)) 254 return; 255 256 for_each_cpu_and(cpu, mask, cpu_online_mask) { 257 if (this_cpu == cpu) 258 continue; 259 260 xen_send_IPI_one(cpu, xen_vector); 261 } 262} 263 264void xen_send_IPI_allbutself(int vector) 265{ 266 xen_send_IPI_mask_allbutself(cpu_online_mask, vector); 267} 268 269static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id) 270{ 271 irq_enter(); 272 generic_smp_call_function_interrupt(); 273 inc_irq_stat(irq_call_count); 274 irq_exit(); 275 276 return IRQ_HANDLED; 277} 278 279static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id) 280{ 281 irq_enter(); 282 generic_smp_call_function_single_interrupt(); 283 inc_irq_stat(irq_call_count); 284 irq_exit(); 285 286 return IRQ_HANDLED; 287} 288