diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/xen/smp.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c new file mode 100644 index 000000000..7a43b2ae1 --- /dev/null +++ b/arch/x86/xen/smp.c @@ -0,0 +1,284 @@ +// 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; +} |