// SPDX-License-Identifier: GPL-2.0 #include <linux/smp.h> #include <linux/cpu.h> #include <linux/slab.h> #include <linux/cpumask.h> #include <linux/percpu.h> #include <xen/events.h> #include <xen/hvc-console.h> #include "xen-ops.h" #include "smp.h" static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 }; static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 }; static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 }; static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 }; static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id); static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id); /* * Reschedule call back. */ static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id) { inc_irq_stat(irq_resched_count); scheduler_ipi(); return IRQ_HANDLED; } void xen_smp_intr_free(unsigned int cpu) { if (per_cpu(xen_resched_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL); per_cpu(xen_resched_irq, cpu).irq = -1; kfree(per_cpu(xen_resched_irq, cpu).name); per_cpu(xen_resched_irq, cpu).name = NULL; } if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL); per_cpu(xen_callfunc_irq, cpu).irq = -1; kfree(per_cpu(xen_callfunc_irq, cpu).name); per_cpu(xen_callfunc_irq, cpu).name = NULL; } if (per_cpu(xen_debug_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL); per_cpu(xen_debug_irq, cpu).irq = -1; kfree(per_cpu(xen_debug_irq, cpu).name); per_cpu(xen_debug_irq, cpu).name = NULL; } if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq, NULL); per_cpu(xen_callfuncsingle_irq, cpu).irq = -1; kfree(per_cpu(xen_callfuncsingle_irq, cpu).name); per_cpu(xen_callfuncsingle_irq, cpu).name = NULL; } } int xen_smp_intr_init(unsigned int cpu) { int rc; char *resched_name, *callfunc_name, *debug_name; resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu); rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, cpu, xen_reschedule_interrupt, IRQF_PERCPU|IRQF_NOBALANCING, resched_name, NULL); if (rc < 0) goto fail; per_cpu(xen_resched_irq, cpu).irq = rc; per_cpu(xen_resched_irq, cpu).name = resched_name; callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu); rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR, cpu, xen_call_function_interrupt, IRQF_PERCPU|IRQF_NOBALANCING, callfunc_name, NULL); if (rc < 0) goto fail; per_cpu(xen_callfunc_irq, cpu).irq = rc; per_cpu(xen_callfunc_irq, cpu).name = callfunc_name; debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu); rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt, IRQF_PERCPU | IRQF_NOBALANCING, debug_name, NULL); if (rc < 0) goto fail; per_cpu(xen_debug_irq, cpu).irq = rc; per_cpu(xen_debug_irq, cpu).name = debug_name; callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu); rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR, cpu, xen_call_function_single_interrupt, IRQF_PERCPU|IRQF_NOBALANCING, callfunc_name, NULL); if (rc < 0) goto fail; per_cpu(xen_callfuncsingle_irq, cpu).irq = rc; per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name; return 0; fail: xen_smp_intr_free(cpu); return rc; } void __init xen_smp_cpus_done(unsigned int max_cpus) { int cpu, rc, count = 0; if (xen_hvm_domain()) native_smp_cpus_done(max_cpus); else calculate_max_logical_packages(); if (xen_have_vcpu_info_placement) return; for_each_online_cpu(cpu) { if (xen_vcpu_nr(cpu) < MAX_VIRT_CPUS) continue; rc = cpu_down(cpu); if (rc == 0) { /* * Reset vcpu_info so this cpu cannot be onlined again. */ xen_vcpu_info_reset(cpu); count++; } else { pr_warn("%s: failed to bring CPU %d down, error %d\n", __func__, cpu, rc); } } WARN(count, "%s: brought %d CPUs offline\n", __func__, count); } void xen_smp_send_reschedule(int cpu) { xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR); } static void __xen_send_IPI_mask(const struct cpumask *mask, int vector) { unsigned cpu; for_each_cpu_and(cpu, mask, cpu_online_mask) xen_send_IPI_one(cpu, vector); } void xen_smp_send_call_function_ipi(const struct cpumask *mask) { int cpu; __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR); /* Make sure other vcpus get a chance to run if they need to. */ for_each_cpu(cpu, mask) { if (xen_vcpu_stolen(cpu)) { HYPERVISOR_sched_op(SCHEDOP_yield, NULL); break; } } } void xen_smp_send_call_function_single_ipi(int cpu) { __xen_send_IPI_mask(cpumask_of(cpu), XEN_CALL_FUNCTION_SINGLE_VECTOR); } static inline int xen_map_vector(int vector) { int xen_vector; switch (vector) { case RESCHEDULE_VECTOR: xen_vector = XEN_RESCHEDULE_VECTOR; break; case CALL_FUNCTION_VECTOR: xen_vector = XEN_CALL_FUNCTION_VECTOR; break; case CALL_FUNCTION_SINGLE_VECTOR: xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR; break; case IRQ_WORK_VECTOR: xen_vector = XEN_IRQ_WORK_VECTOR; break; #ifdef CONFIG_X86_64 case NMI_VECTOR: case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */ xen_vector = XEN_NMI_VECTOR; break; #endif default: xen_vector = -1; printk(KERN_ERR "xen: vector 0x%x is not implemented\n", vector); } return xen_vector; } void xen_send_IPI_mask(const struct cpumask *mask, int vector) { int xen_vector = xen_map_vector(vector); if (xen_vector >= 0) __xen_send_IPI_mask(mask, xen_vector); } void xen_send_IPI_all(int vector) { int xen_vector = xen_map_vector(vector); if (xen_vector >= 0) __xen_send_IPI_mask(cpu_online_mask, xen_vector); } void xen_send_IPI_self(int vector) { int xen_vector = xen_map_vector(vector); if (xen_vector >= 0) xen_send_IPI_one(smp_processor_id(), xen_vector); } void xen_send_IPI_mask_allbutself(const struct cpumask *mask, int vector) { unsigned cpu; unsigned int this_cpu = smp_processor_id(); int xen_vector = xen_map_vector(vector); if (!(num_online_cpus() > 1) || (xen_vector < 0)) return; for_each_cpu_and(cpu, mask, cpu_online_mask) { if (this_cpu == cpu) continue; xen_send_IPI_one(cpu, xen_vector); } } void xen_send_IPI_allbutself(int vector) { xen_send_IPI_mask_allbutself(cpu_online_mask, vector); } static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id) { irq_enter(); generic_smp_call_function_interrupt(); inc_irq_stat(irq_call_count); irq_exit(); return IRQ_HANDLED; } static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id) { irq_enter(); generic_smp_call_function_single_interrupt(); inc_irq_stat(irq_call_count); irq_exit(); return IRQ_HANDLED; }