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   1 /*
   2  *      linux/arch/x86_64/kernel/irq.c
   3  *
   4  *      Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
   5  *
   6  * This file contains the lowest level x86_64-specific interrupt
   7  * entry and irq statistics code. All the remaining irq logic is
   8  * done by the generic kernel/irq/ code and in the
   9  * x86_64-specific irq controller code. (e.g. i8259.c and
  10  * io_apic.c.)
  11  */
  12
  13 #include <linux/kernel_stat.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/seq_file.h>
  16 #include <linux/module.h>
  17 #include <linux/delay.h>
  18 #include <asm/uaccess.h>
  19 #include <asm/io_apic.h>
  20 #include <asm/idle.h>
  21
  22 atomic_t irq_err_count;
  23 #ifdef CONFIG_X86_IO_APIC
  24 #ifdef APIC_MISMATCH_DEBUG
  25 atomic_t irq_mis_count;
  26 #endif
  27 #endif
  28
  29 /*
  30  * Generic, controller-independent functions:
  31  */
  32
  33 int show_interrupts(struct seq_file *p, void *v)
  34 {
  35         int i = *(loff_t *) v, j;
  36         struct irqaction * action;
  37         unsigned long flags;
  38
  39         if (i == 0) {
  40                 seq_printf(p, "           ");
  41                 for (j=0; j<NR_CPUS; j++)
  42                         if (cpu_online(j))
  43                                 seq_printf(p, "CPU%d       ",j);
  44                 seq_putc(p, '\n');
  45         }
  46
  47         if (i < NR_IRQS) {
  48                 spin_lock_irqsave(&irq_desc[i].lock, flags);
  49                 action = irq_desc[i].action;
  50                 if (!action)
  51                         goto skip;
  52                 seq_printf(p, "%3d: ",i);
  53 #ifndef CONFIG_SMP
  54                 seq_printf(p, "%10u ", kstat_irqs(i));
  55 #else
  56                 for (j=0; j<NR_CPUS; j++)
  57                         if (cpu_online(j))
  58                         seq_printf(p, "%10u ",
  59                                 kstat_cpu(j).irqs[i]);
  60 #endif
  61                 seq_printf(p, " %14s", irq_desc[i].handler->typename);
  62
  63                 seq_printf(p, "  %s", action->name);
  64                 for (action=action->next; action; action = action->next)
  65                         seq_printf(p, ", %s", action->name);
  66                 seq_putc(p, '\n');
  67 skip:
  68                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
  69         } else if (i == NR_IRQS) {
  70                 seq_printf(p, "NMI: ");
  71                 for (j = 0; j < NR_CPUS; j++)
  72                         if (cpu_online(j))
  73                                 seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
  74                 seq_putc(p, '\n');
  75 #ifdef CONFIG_X86_LOCAL_APIC
  76                 seq_printf(p, "LOC: ");
  77                 for (j = 0; j < NR_CPUS; j++)
  78                         if (cpu_online(j))
  79                                 seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
  80                 seq_putc(p, '\n');
  81 #endif
  82                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
  83 #ifdef CONFIG_X86_IO_APIC
  84 #ifdef APIC_MISMATCH_DEBUG
  85                 seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count));
  86 #endif
  87 #endif
  88         }
  89         return 0;
  90 }
  91
  92 /*
  93  * do_IRQ handles all normal device IRQ's (the special
  94  * SMP cross-CPU interrupts have their own specific
  95  * handlers).
  96  */
  97 asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
  98 {
  99         /* high bits used in ret_from_ code  */
 100         unsigned irq = regs->orig_rax & 0xff;
 101
 102         exit_idle();
 103         irq_enter();
 104
 105         __do_IRQ(irq, regs);
 106         irq_exit();
 107
 108         return 1;
 109 }
 110
 111 #ifdef CONFIG_HOTPLUG_CPU
 112 void fixup_irqs(cpumask_t map)
 113 {
 114         unsigned int irq;
 115         static int warned;
 116
 117         for (irq = 0; irq < NR_IRQS; irq++) {
 118                 cpumask_t mask;
 119                 if (irq == 2)
 120                         continue;
 121
 122                 cpus_and(mask, irq_affinity[irq], map);
 123                 if (any_online_cpu(mask) == NR_CPUS) {
 124                         printk("Breaking affinity for irq %i\n", irq);
 125                         mask = map;
 126                 }
 127                 if (irq_desc[irq].handler->set_affinity)
 128                         irq_desc[irq].handler->set_affinity(irq, mask);
 129                 else if (irq_desc[irq].action && !(warned++))
 130                         printk("Cannot set affinity for irq %i\n", irq);
 131         }
 132
 133         /* That doesn't seem sufficient.  Give it 1ms. */
 134         local_irq_enable();
 135         mdelay(1);
 136         local_irq_disable();
 137 }
 138 #endif
 139
 140 extern void call_softirq(void);
 141
 142 asmlinkage void do_softirq(void)
 143 {
 144         __u32 pending;
 145         unsigned long flags;
 146
 147         if (in_interrupt())
 148                 return;
 149
 150         local_irq_save(flags);
 151         pending = local_softirq_pending();
 152         /* Switch to interrupt stack */
 153         if (pending)
 154                 call_softirq();
 155         local_irq_restore(flags);
 156 }
 157 EXPORT_SYMBOL(do_softirq);