/arch/x86/kernel/irq.c
C | 366 lines | 260 code | 57 blank | 49 comment | 39 complexity | cf231e3ca6955b67140e227df238f215 MD5 | raw file
- /*
- * Common interrupt code for 32 and 64 bit
- */
- #include <linux/cpu.h>
- #include <linux/interrupt.h>
- #include <linux/kernel_stat.h>
- #include <linux/seq_file.h>
- #include <linux/smp.h>
- #include <linux/ftrace.h>
- #include <asm/apic.h>
- #include <asm/io_apic.h>
- #include <asm/irq.h>
- #include <asm/idle.h>
- #include <asm/mce.h>
- #include <asm/hw_irq.h>
- 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:
- */
- static int show_other_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_printf(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_printf(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_printf(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_printf(p, " Performance monitoring interrupts\n");
- seq_printf(p, "%*s: ", prec, "PND");
- for_each_online_cpu(j)
- seq_printf(p, "%10u ", irq_stats(j)->apic_pending_irqs);
- seq_printf(p, " Performance pending work\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_printf(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_printf(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_printf(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_printf(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_printf(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_printf(p, " Threshold 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_printf(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_printf(p, " Machine check polls\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
- return 0;
- }
- int show_interrupts(struct seq_file *p, void *v)
- {
- unsigned long flags, any_count = 0;
- int i = *(loff_t *) v, j, prec;
- struct irqaction *action;
- struct irq_desc *desc;
- if (i > nr_irqs)
- return 0;
- for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
- j *= 10;
- if (i == nr_irqs)
- return show_other_interrupts(p, prec);
- /* print header */
- if (i == 0) {
- seq_printf(p, "%*s", prec + 8, "");
- for_each_online_cpu(j)
- seq_printf(p, "CPU%-8d", j);
- seq_putc(p, '\n');
- }
- desc = irq_to_desc(i);
- if (!desc)
- return 0;
- raw_spin_lock_irqsave(&desc->lock, flags);
- for_each_online_cpu(j)
- any_count |= kstat_irqs_cpu(i, j);
- action = desc->action;
- if (!action && !any_count)
- goto out;
- seq_printf(p, "%*d: ", prec, i);
- for_each_online_cpu(j)
- seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
- seq_printf(p, " %8s", desc->chip->name);
- seq_printf(p, "-%-8s", desc->name);
- if (action) {
- seq_printf(p, " %s", action->name);
- while ((action = action->next) != NULL)
- seq_printf(p, ", %s", action->name);
- }
- seq_putc(p, '\n');
- out:
- raw_spin_unlock_irqrestore(&desc->lock, flags);
- 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_pending_irqs;
- #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;
- sum += irq_stats(cpu)->irq_tlb_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);
- #ifdef CONFIG_X86_IO_APIC
- sum += atomic_read(&irq_mis_count);
- #endif
- return sum;
- }
- /*
- * do_IRQ handles all normal device IRQ's (the special
- * SMP cross-CPU interrupts have their own specific
- * handlers).
- */
- unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
- {
- struct pt_regs *old_regs = set_irq_regs(regs);
- /* high bit used in ret_from_ code */
- unsigned vector = ~regs->orig_ax;
- unsigned irq;
- exit_idle();
- irq_enter();
- irq = __get_cpu_var(vector_irq)[vector];
- if (!handle_irq(irq, regs)) {
- ack_APIC_irq();
- if (printk_ratelimit())
- pr_emerg("%s: %d.%d No irq handler for vector (irq %d)\n",
- __func__, smp_processor_id(), vector, irq);
- }
- irq_exit();
- set_irq_regs(old_regs);
- return 1;
- }
- /*
- * Handler for X86_PLATFORM_IPI_VECTOR.
- */
- void smp_x86_platform_ipi(struct pt_regs *regs)
- {
- struct pt_regs *old_regs = set_irq_regs(regs);
- ack_APIC_irq();
- exit_idle();
- irq_enter();
- inc_irq_stat(x86_platform_ipis);
- if (x86_platform_ipi_callback)
- x86_platform_ipi_callback();
- irq_exit();
- set_irq_regs(old_regs);
- }
- EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
- #ifdef CONFIG_HOTPLUG_CPU
- /* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
- void fixup_irqs(void)
- {
- unsigned int irq, vector;
- static int warned;
- struct irq_desc *desc;
- for_each_irq_desc(irq, desc) {
- int break_affinity = 0;
- int set_affinity = 1;
- const struct cpumask *affinity;
- if (!desc)
- continue;
- if (irq == 2)
- continue;
- /* interrupt's are disabled at this point */
- raw_spin_lock(&desc->lock);
- affinity = desc->affinity;
- if (!irq_has_action(irq) ||
- cpumask_equal(affinity, cpu_online_mask)) {
- raw_spin_unlock(&desc->lock);
- continue;
- }
- /*
- * Complete the irq move. This cpu is going down and for
- * non intr-remapping case, we can't wait till this interrupt
- * arrives at this cpu before completing the irq move.
- */
- irq_force_complete_move(irq);
- if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
- break_affinity = 1;
- affinity = cpu_all_mask;
- }
- if (!(desc->status & IRQ_MOVE_PCNTXT) && desc->chip->mask)
- desc->chip->mask(irq);
- if (desc->chip->set_affinity)
- desc->chip->set_affinity(irq, affinity);
- else if (!(warned++))
- set_affinity = 0;
- if (!(desc->status & IRQ_MOVE_PCNTXT) && desc->chip->unmask)
- desc->chip->unmask(irq);
- raw_spin_unlock(&desc->lock);
- if (break_affinity && set_affinity)
- printk("Broke affinity for irq %i\n", irq);
- else if (!set_affinity)
- printk("Cannot set affinity for irq %i\n", irq);
- }
- /*
- * 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);
- for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
- unsigned int irr;
- if (__get_cpu_var(vector_irq)[vector] < 0)
- continue;
- irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
- if (irr & (1 << (vector % 32))) {
- irq = __get_cpu_var(vector_irq)[vector];
- desc = irq_to_desc(irq);
- raw_spin_lock(&desc->lock);
- if (desc->chip->retrigger)
- desc->chip->retrigger(irq);
- raw_spin_unlock(&desc->lock);
- }
- }
- }
- #endif