path: root/arch/x86/kernel/irq.c

/*
 * 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 <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>

#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);

DEFINE_PER_CPU(struct pt_regs *, irq_regs);
EXPORT_PER_CPU_SYMBOL(irq_regs);

atomic_t irq_err_count;

/* Function pointer for generic interrupt vector handling */
void (*x86_platform_ipi_callback)(void) = NULL;

/*
 * '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");
#endif
	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");
	}
#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
#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, used_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
	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, "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;
#endif
	if (x86_platform_ipi_callback)
		sum += irq_stats(cpu)->x86_platform_ipis;
#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;
}


/*
 * do_IRQ handles all normal device IRQ's (the special
 * SMP cross-CPU interrupts have their own specific
 * handlers).
 */
__visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
{
	struct pt_regs *old_regs = set_irq_regs(regs);
	struct irq_desc * desc;
	/* high bit used in ret_from_ code  */