diff options
Diffstat (limited to 'arch/x86/kernel/irq.c')
| -rw-r--r-- | arch/x86/kernel/irq.c | 378 |
1 files changed, 378 insertions, 0 deletions
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c new file mode 100644 index 000000000..ce904c89c --- /dev/null +++ b/arch/x86/kernel/irq.c @@ -0,0 +1,378 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Common interrupt code for 32 and 64 bit + */ +#include <linux/cpu.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/of.h> +#include <linux/seq_file.h> +#include <linux/smp.h> +#include <linux/ftrace.h> +#include <linux/delay.h> +#include <linux/export.h> +#include <linux/irq.h> + +#include <asm/irq_stack.h> +#include <asm/apic.h> +#include <asm/io_apic.h> +#include <asm/irq.h> +#include <asm/mce.h> +#include <asm/hw_irq.h> +#include <asm/desc.h> +#include <asm/traps.h> + +#define CREATE_TRACE_POINTS +#include <asm/trace/irq_vectors.h> + +DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat); +EXPORT_PER_CPU_SYMBOL(irq_stat); + +atomic_t irq_err_count; + +/* + * 'what should we do if we get a hw irq event on an illegal vector'. + * each architecture has to answer this themselves. + */ +void ack_bad_irq(unsigned int irq) +{ + if (printk_ratelimit()) + pr_err("unexpected IRQ trap at vector %02x\n", irq); + + /* + * Currently unexpected vectors happen only on SMP and APIC. + * We _must_ ack these because every local APIC has only N + * irq slots per priority level, and a 'hanging, unacked' IRQ + * holds up an irq slot - in excessive cases (when multiple + * unexpected vectors occur) that might lock up the APIC + * completely. + * But only ack when the APIC is enabled -AK + */ + ack_APIC_irq(); +} + +#define irq_stats(x) (&per_cpu(irq_stat, x)) +/* + * /proc/interrupts printing for arch specific interrupts + */ +int arch_show_interrupts(struct seq_file *p, int prec) +{ + int j; + + seq_printf(p, "%*s: ", prec, "NMI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->__nmi_count); + seq_puts(p, " Non-maskable interrupts\n"); +#ifdef CONFIG_X86_LOCAL_APIC + seq_printf(p, "%*s: ", prec, "LOC"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs); + seq_puts(p, " Local timer interrupts\n"); + + seq_printf(p, "%*s: ", prec, "SPU"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count); + seq_puts(p, " Spurious interrupts\n"); + seq_printf(p, "%*s: ", prec, "PMI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs); + seq_puts(p, " Performance monitoring interrupts\n"); + seq_printf(p, "%*s: ", prec, "IWI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->apic_irq_work_irqs); + seq_puts(p, " IRQ work interrupts\n"); + seq_printf(p, "%*s: ", prec, "RTR"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->icr_read_retry_count); + seq_puts(p, " APIC ICR read retries\n"); + if (x86_platform_ipi_callback) { + seq_printf(p, "%*s: ", prec, "PLT"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis); + seq_puts(p, " Platform interrupts\n"); + } +#endif +#ifdef CONFIG_SMP + seq_printf(p, "%*s: ", prec, "RES"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count); + seq_puts(p, " Rescheduling interrupts\n"); + seq_printf(p, "%*s: ", prec, "CAL"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_call_count); + seq_puts(p, " Function call interrupts\n"); + seq_printf(p, "%*s: ", prec, "TLB"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count); + seq_puts(p, " TLB shootdowns\n"); +#endif +#ifdef CONFIG_X86_THERMAL_VECTOR + seq_printf(p, "%*s: ", prec, "TRM"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count); + seq_puts(p, " Thermal event interrupts\n"); +#endif +#ifdef CONFIG_X86_MCE_THRESHOLD + seq_printf(p, "%*s: ", prec, "THR"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count); + seq_puts(p, " Threshold APIC interrupts\n"); +#endif +#ifdef CONFIG_X86_MCE_AMD + seq_printf(p, "%*s: ", prec, "DFR"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count); + seq_puts(p, " Deferred Error APIC interrupts\n"); +#endif +#ifdef CONFIG_X86_MCE + seq_printf(p, "%*s: ", prec, "MCE"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(mce_exception_count, j)); + seq_puts(p, " Machine check exceptions\n"); + seq_printf(p, "%*s: ", prec, "MCP"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", per_cpu(mce_poll_count, j)); + seq_puts(p, " Machine check polls\n"); +#endif +#ifdef CONFIG_X86_HV_CALLBACK_VECTOR + if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) { + seq_printf(p, "%*s: ", prec, "HYP"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + irq_stats(j)->irq_hv_callback_count); + seq_puts(p, " Hypervisor callback interrupts\n"); + } +#endif +#if IS_ENABLED(CONFIG_HYPERV) + if (test_bit(HYPERV_REENLIGHTENMENT_VECTOR, system_vectors)) { + seq_printf(p, "%*s: ", prec, "HRE"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + irq_stats(j)->irq_hv_reenlightenment_count); + seq_puts(p, " Hyper-V reenlightenment interrupts\n"); + } + if (test_bit(HYPERV_STIMER0_VECTOR, system_vectors)) { + seq_printf(p, "%*s: ", prec, "HVS"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + irq_stats(j)->hyperv_stimer0_count); + seq_puts(p, " Hyper-V stimer0 interrupts\n"); + } +#endif + seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count)); +#if defined(CONFIG_X86_IO_APIC) + seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count)); +#endif +#ifdef CONFIG_HAVE_KVM + seq_printf(p, "%*s: ", prec, "PIN"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->kvm_posted_intr_ipis); + seq_puts(p, " Posted-interrupt notification event\n"); + + seq_printf(p, "%*s: ", prec, "NPI"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + irq_stats(j)->kvm_posted_intr_nested_ipis); + seq_puts(p, " Nested posted-interrupt event\n"); + + seq_printf(p, "%*s: ", prec, "PIW"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", + irq_stats(j)->kvm_posted_intr_wakeup_ipis); + seq_puts(p, " Posted-interrupt wakeup event\n"); +#endif + return 0; +} + +/* + * /proc/stat helpers + */ +u64 arch_irq_stat_cpu(unsigned int cpu) +{ + u64 sum = irq_stats(cpu)->__nmi_count; + +#ifdef CONFIG_X86_LOCAL_APIC + sum += irq_stats(cpu)->apic_timer_irqs; + sum += irq_stats(cpu)->irq_spurious_count; + sum += irq_stats(cpu)->apic_perf_irqs; + sum += irq_stats(cpu)->apic_irq_work_irqs; + sum += irq_stats(cpu)->icr_read_retry_count; + if (x86_platform_ipi_callback) + sum += irq_stats(cpu)->x86_platform_ipis; +#endif +#ifdef CONFIG_SMP + sum += irq_stats(cpu)->irq_resched_count; + sum += irq_stats(cpu)->irq_call_count; +#endif +#ifdef CONFIG_X86_THERMAL_VECTOR + sum += irq_stats(cpu)->irq_thermal_count; +#endif +#ifdef CONFIG_X86_MCE_THRESHOLD + sum += irq_stats(cpu)->irq_threshold_count; +#endif +#ifdef CONFIG_X86_MCE + sum += per_cpu(mce_exception_count, cpu); + sum += per_cpu(mce_poll_count, cpu); +#endif + return sum; +} + +u64 arch_irq_stat(void) +{ + u64 sum = atomic_read(&irq_err_count); + return sum; +} + +static __always_inline void handle_irq(struct irq_desc *desc, + struct pt_regs *regs) +{ + if (IS_ENABLED(CONFIG_X86_64)) + run_irq_on_irqstack_cond(desc->handle_irq, desc, regs); + else + __handle_irq(desc, regs); +} + +/* + * common_interrupt() handles all normal device IRQ's (the special SMP + * cross-CPU interrupts have their own entry points). + */ +DEFINE_IDTENTRY_IRQ(common_interrupt) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + struct irq_desc *desc; + + /* entry code tells RCU that we're not quiescent. Check it. */ + RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU"); + + desc = __this_cpu_read(vector_irq[vector]); + if (likely(!IS_ERR_OR_NULL(desc))) { + handle_irq(desc, regs); + } else { + ack_APIC_irq(); + + if (desc == VECTOR_UNUSED) { + pr_emerg_ratelimited("%s: %d.%u No irq handler for vector\n", + __func__, smp_processor_id(), + vector); + } else { + __this_cpu_write(vector_irq[vector], VECTOR_UNUSED); + } + } + + set_irq_regs(old_regs); +} + +#ifdef CONFIG_X86_LOCAL_APIC +/* Function pointer for generic interrupt vector handling */ +void (*x86_platform_ipi_callback)(void) = NULL; +/* + * Handler for X86_PLATFORM_IPI_VECTOR. + */ +DEFINE_IDTENTRY_SYSVEC(sysvec_x86_platform_ipi) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + ack_APIC_irq(); + trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR); + inc_irq_stat(x86_platform_ipis); + if (x86_platform_ipi_callback) + x86_platform_ipi_callback(); + trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR); + set_irq_regs(old_regs); +} +#endif + +#ifdef CONFIG_HAVE_KVM +static void dummy_handler(void) {} +static void (*kvm_posted_intr_wakeup_handler)(void) = dummy_handler; + +void kvm_set_posted_intr_wakeup_handler(void (*handler)(void)) +{ + if (handler) + kvm_posted_intr_wakeup_handler = handler; + else { + kvm_posted_intr_wakeup_handler = dummy_handler; + synchronize_rcu(); + } +} +EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler); + +/* + * Handler for POSTED_INTERRUPT_VECTOR. + */ +DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_ipi) +{ + ack_APIC_irq(); + inc_irq_stat(kvm_posted_intr_ipis); +} + +/* + * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR. + */ +DEFINE_IDTENTRY_SYSVEC(sysvec_kvm_posted_intr_wakeup_ipi) +{ + ack_APIC_irq(); + inc_irq_stat(kvm_posted_intr_wakeup_ipis); + kvm_posted_intr_wakeup_handler(); +} + +/* + * Handler for POSTED_INTERRUPT_NESTED_VECTOR. + */ +DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_nested_ipi) +{ + ack_APIC_irq(); + inc_irq_stat(kvm_posted_intr_nested_ipis); +} +#endif + + +#ifdef CONFIG_HOTPLUG_CPU +/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */ +void fixup_irqs(void) +{ + unsigned int irr, vector; + struct irq_desc *desc; + struct irq_data *data; + struct irq_chip *chip; + + irq_migrate_all_off_this_cpu(); + + /* + * We can remove mdelay() and then send spuriuous interrupts to + * new cpu targets for all the irqs that were handled previously by + * this cpu. While it works, I have seen spurious interrupt messages + * (nothing wrong but still...). + * + * So for now, retain mdelay(1) and check the IRR and then send those + * interrupts to new targets as this cpu is already offlined... + */ + mdelay(1); + + /* + * We can walk the vector array of this cpu without holding + * vector_lock because the cpu is already marked !online, so + * nothing else will touch it. + */ + for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) { + if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector]))) + continue; + + irr = apic_read(APIC_IRR + (vector / 32 * 0x10)); + if (irr & (1 << (vector % 32))) { + desc = __this_cpu_read(vector_irq[vector]); + + raw_spin_lock(&desc->lock); + data = irq_desc_get_irq_data(desc); + chip = irq_data_get_irq_chip(data); + if (chip->irq_retrigger) { + chip->irq_retrigger(data); + __this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED); + } + raw_spin_unlock(&desc->lock); + } + if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED) + __this_cpu_write(vector_irq[vector], VECTOR_UNUSED); + } +} +#endif |