/* * linux/arch/x86_64/kernel/irq.c * * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar * * This file contains the lowest level x86_64-specific interrupt * entry and irq statistics code. All the remaining irq logic is * done by the generic kernel/irq/ code and in the * x86_64-specific irq controller code. (e.g. i8259.c and * io_apic.c.) */ #include <linux/kernel_stat.h> #include <linux/interrupt.h> #include <linux/seq_file.h> #include <linux/module.h> #include <linux/delay.h> #include <asm/uaccess.h> #include <asm/io_apic.h> #include <asm/idle.h> #include <asm/smp.h> atomic_t irq_err_count; #ifdef CONFIG_DEBUG_STACKOVERFLOW /* * Probabilistic stack overflow check: * * Only check the stack in process context, because everything else * runs on the big interrupt stacks. Checking reliably is too expensive, * so we just check from interrupts. */ static inline void stack_overflow_check(struct pt_regs *regs) { u64 curbase = (u64)task_stack_page(current); static unsigned long warned = -60*HZ; if (regs->rsp >= curbase && regs->rsp <= curbase + THREAD_SIZE && regs->rsp < curbase + sizeof(struct thread_info) + 128 && time_after(jiffies, warned + 60*HZ)) { printk("do_IRQ: %s near stack overflow (cur:%Lx,rsp:%lx)\n", current->comm, curbase, regs->rsp); show_stack(NULL,NULL); warned = jiffies; } } #endif /* * Generic, controller-independent functions: */ int show_interrupts(struct seq_file *p, void *v) { int i = *(loff_t *) v, j; struct irqaction * action; unsigned long flags; if (i == 0) { seq_printf(p, " "); for_each_online_cpu(j) seq_printf(p, "CPU%-8d",j); seq_putc(p, '\n'); } if (i < NR_IRQS) { spin_lock_irqsave(&irq_desc[i].lock, flags); action = irq_desc[i].action; if (!action) goto skip; seq_printf(p, "%3d: ",i); #ifndef CONFIG_SMP seq_printf(p, "%10u ", kstat_irqs(i)); #else for_each_online_cpu(j) seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); #endif seq_printf(p, " %8s", irq_desc[i].chip->name); seq_printf(p, "-%-8s", irq_desc[i].name); seq_printf(p, " %s", action->name); for (action=action->next; action; action = action->next) seq_printf(p, ", %s", action->name); seq_putc(p, '\n'); skip: spin_unlock_irqrestore(&irq_desc[i].lock, flags); } else if (i == NR_IRQS) { seq_printf(p, "NMI: "); for_each_online_cpu(j) seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count); seq_putc(p, '\n'); seq_printf(p, "LOC: "); for_each_online_cpu(j) seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs); seq_putc(p, '\n'); seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); } return 0; } /* * do_IRQ handles all normal device IRQ's (the special * SMP cross-CPU interrupts have their own specific * handlers). */ asmlinkage unsigned int 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_rax; unsigned irq; exit_idle(); irq_enter(); irq = __get_cpu_var(vector_irq)[vector]; #ifdef CONFIG_DEBUG_STACKOVERFLOW stack_overflow_check(regs); #endif if (likely(irq < NR_IRQS)) generic_handle_irq(irq); else { if (!disable_apic) ack_APIC_irq(); if (printk_ratelimit()) printk(KERN_EMERG "%s: %d.%d No irq handler for vector\n", __func__, smp_processor_id(), vector); } irq_exit(); set_irq_regs(old_regs); return 1; } #ifdef CONFIG_HOTPLUG_CPU void fixup_irqs(cpumask_t map) { unsigned int irq; static int warned; for (irq = 0; irq < NR_IRQS; irq++) { cpumask_t mask; int break_affinity = 0; int set_affinity = 1; if (irq == 2) continue; /* interrupt's are disabled at this point */ spin_lock(&irq_desc[irq].lock); if (!irq_has_action(irq) || cpus_equal(irq_desc[irq].affinity, map)) { spin_unlock(&irq_desc[irq].lock); continue; } cpus_and(mask, irq_desc[irq].affinity, map); if (cpus_empty(mask)) { break_affinity = 1; mask = map; } if (irq_desc[irq].chip->mask) irq_desc[irq].chip->mask(irq); if (irq_desc[irq].chip->set_affinity) irq_desc[irq].chip->set_affinity(irq, mask); else if (!(warned++)) set_affinity = 0; if (irq_desc[irq].chip->unmask) irq_desc[irq].chip->unmask(irq); spin_unlock(&irq_desc[irq].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); } /* That doesn't seem sufficient. Give it 1ms. */ local_irq_enable(); mdelay(1); local_irq_disable(); } #endif extern void call_softirq(void); asmlinkage void do_softirq(void) { __u32 pending; unsigned long flags; if (in_interrupt()) return; local_irq_save(flags); pending = local_softirq_pending(); /* Switch to interrupt stack */ if (pending) { call_softirq(); WARN_ON_ONCE(softirq_count()); } local_irq_restore(flags); } EXPORT_SYMBOL(do_softirq);