diff options
Diffstat (limited to 'arch/x86_64/kernel/irq_64.c')
| -rw-r--r-- | arch/x86_64/kernel/irq_64.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/irq_64.c b/arch/x86_64/kernel/irq_64.c new file mode 100644 index 00000000000..39cb3fa83eb --- /dev/null +++ b/arch/x86_64/kernel/irq_64.c @@ -0,0 +1,213 @@ +/* + * 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); |