arch/xen/x86_64/kernel/irq.c

   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 #include <asm/uaccess.h>
  13 #include <linux/module.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/kernel_stat.h>
  17
  18 /*
  19  * Interrupt statistics:
  20  */
  21
  22 atomic_t irq_err_count;
  23
  24
  25 /*
  26  * Generic, controller-independent functions:
  27  */
  28
  29 int show_interrupts(struct seq_file *p, void *v)
  30 {
  31         int i = *(loff_t *) v, j;
  32         struct irqaction * action;
  33         unsigned long flags;
  34
  35         if (i == 0) {
  36                 seq_printf(p, "           ");
  37                 for (j=0; j<NR_CPUS; j++)
  38                         if (cpu_online(j))
  39                                 seq_printf(p, "CPU%d       ",j);
  40                 seq_putc(p, '\n');
  41         }
  42
  43         if (i < NR_IRQS) {
  44                 spin_lock_irqsave(&irq_desc[i].lock, flags);
  45                 action = irq_desc[i].action;
  46                 if (!action)
  47                         goto skip;
  48                 seq_printf(p, "%3d: ",i);
  49 #ifndef CONFIG_SMP
  50                 seq_printf(p, "%10u ", kstat_irqs(i));
  51 #else
  52                 for (j=0; j<NR_CPUS; j++)
  53                         if (cpu_online(j))
  54                         seq_printf(p, "%10u ",
  55                                 kstat_cpu(j).irqs[i]);
  56 #endif
  57                 seq_printf(p, " %14s", irq_desc[i].handler->typename);
  58
  59                 seq_printf(p, "  %s", action->name);
  60                 for (action=action->next; action; action = action->next)
  61                         seq_printf(p, ", %s", action->name);
  62                 seq_putc(p, '\n');
  63 skip:
  64                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
  65         } else if (i == NR_IRQS) {
  66                 seq_printf(p, "NMI: ");
  67                 for (j = 0; j < NR_CPUS; j++)
  68                         if (cpu_online(j))
  69                                 seq_printf(p, "%10u ", cpu_pda[j].__nmi_count);
  70                 seq_putc(p, '\n');
  71 #ifdef CONFIG_X86_LOCAL_APIC
  72                 seq_printf(p, "LOC: ");
  73                 for (j = 0; j < NR_CPUS; j++)
  74                         if (cpu_online(j))
  75                                 seq_printf(p, "%10u ", cpu_pda[j].apic_timer_irqs);
  76                 seq_putc(p, '\n');
  77 #endif
  78                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
  79 #ifdef CONFIG_X86_IO_APIC
  80 #ifdef APIC_MISMATCH_DEBUG
  81                 seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count));
  82 #endif
  83 #endif
  84         }
  85         return 0;
  86 }
  87
  88 /*
  89  * do_IRQ handles all normal device IRQ's (the special
  90  * SMP cross-CPU interrupts have their own specific
  91  * handlers).
  92  */
  93 asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
  94 {
  95         /* high bits used in ret_from_ code  */
  96         int irq = regs->orig_rax & __IRQ_MASK(HARDIRQ_BITS);
  97
  98         irq_enter();
  99
 100         __do_IRQ(irq, regs);
 101         irq_exit();
 102
 103         return 1;
 104 }
 105