arch/x86/kernel/irq.c

   1 /*
   2  * Common interrupt code for 32 and 64 bit
   3  */
   4 #include <linux/cpu.h>
   5 #include <linux/interrupt.h>
   6 #include <linux/kernel_stat.h>
   7 #include <linux/seq_file.h>
   8 #include <linux/smp.h>
   9 #include <linux/ftrace.h>
  10
  11 #include <asm/apic.h>
  12 #include <asm/io_apic.h>
  13 #include <asm/irq.h>
  14 #include <asm/idle.h>
  15 #include <asm/hw_irq.h>
  16
  17 atomic_t irq_err_count;
  18
  19 /* Function pointer for generic interrupt vector handling */
  20 void (*generic_interrupt_extension)(void) = NULL;
  21
  22 /*
  23  * 'what should we do if we get a hw irq event on an illegal vector'.
  24  * each architecture has to answer this themselves.
  25  */
  26 void ack_bad_irq(unsigned int irq)
  27 {
  28         printk(KERN_ERR "unexpected IRQ trap at vector %02x\n", irq);
  29
  30 #ifdef CONFIG_X86_LOCAL_APIC
  31         /*
  32          * Currently unexpected vectors happen only on SMP and APIC.
  33          * We _must_ ack these because every local APIC has only N
  34          * irq slots per priority level, and a 'hanging, unacked' IRQ
  35          * holds up an irq slot - in excessive cases (when multiple
  36          * unexpected vectors occur) that might lock up the APIC
  37          * completely.
  38          * But only ack when the APIC is enabled -AK
  39          */
  40         if (cpu_has_apic)
  41                 ack_APIC_irq();
  42 #endif
  43 }
  44
  45 #define irq_stats(x)            (&per_cpu(irq_stat, x))
  46 /*
  47  * /proc/interrupts printing:
  48  */
  49 static int show_other_interrupts(struct seq_file *p, int prec)
  50 {
  51         int j;
  52
  53         seq_printf(p, "%*s: ", prec, "NMI");
  54         for_each_online_cpu(j)
  55                 seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
  56         seq_printf(p, "  Non-maskable interrupts\n");
  57 #ifdef CONFIG_X86_LOCAL_APIC
  58         seq_printf(p, "%*s: ", prec, "LOC");
  59         for_each_online_cpu(j)
  60                 seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
  61         seq_printf(p, "  Local timer interrupts\n");
  62
  63         seq_printf(p, "%*s: ", prec, "SPU");
  64         for_each_online_cpu(j)
  65                 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
  66         seq_printf(p, "  Spurious interrupts\n");
  67 #endif
  68         if (generic_interrupt_extension) {
  69                 seq_printf(p, "PLT: ");
  70                 for_each_online_cpu(j)
  71                         seq_printf(p, "%10u ", irq_stats(j)->generic_irqs);
  72                 seq_printf(p, "  Platform interrupts\n");
  73         }
  74 #ifdef CONFIG_SMP
  75         seq_printf(p, "%*s: ", prec, "RES");
  76         for_each_online_cpu(j)
  77                 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
  78         seq_printf(p, "  Rescheduling interrupts\n");
  79         seq_printf(p, "%*s: ", prec, "CAL");
  80         for_each_online_cpu(j)
  81                 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
  82         seq_printf(p, "  Function call interrupts\n");
  83         seq_printf(p, "%*s: ", prec, "TLB");
  84         for_each_online_cpu(j)
  85                 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
  86         seq_printf(p, "  TLB shootdowns\n");
  87 #endif
  88 #ifdef CONFIG_X86_MCE
  89         seq_printf(p, "%*s: ", prec, "TRM");
  90         for_each_online_cpu(j)
  91                 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
  92         seq_printf(p, "  Thermal event interrupts\n");
  93 # ifdef CONFIG_X86_64
  94         seq_printf(p, "%*s: ", prec, "THR");
  95         for_each_online_cpu(j)
  96                 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
  97         seq_printf(p, "  Threshold APIC interrupts\n");
  98 # endif
  99 #endif
 100         seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
 101 #if defined(CONFIG_X86_IO_APIC)
 102         seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
 103 #endif
 104         return 0;
 105 }
 106
 107 int show_interrupts(struct seq_file *p, void *v)
 108 {
 109         unsigned long flags, any_count = 0;
 110         int i = *(loff_t *) v, j, prec;
 111         struct irqaction *action;
 112         struct irq_desc *desc;
 113
 114         if (i > nr_irqs)
 115                 return 0;
 116
 117         for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
 118                 j *= 10;
 119
 120         if (i == nr_irqs)
 121                 return show_other_interrupts(p, prec);
 122
 123         /* print header */
 124         if (i == 0) {
 125                 seq_printf(p, "%*s", prec + 8, "");
 126                 for_each_online_cpu(j)
 127                         seq_printf(p, "CPU%-8d", j);
 128                 seq_putc(p, '\n');
 129         }
 130
 131         desc = irq_to_desc(i);
 132         if (!desc)
 133                 return 0;
 134
 135         spin_lock_irqsave(&desc->lock, flags);
 136         for_each_online_cpu(j)
 137                 any_count |= kstat_irqs_cpu(i, j);
 138         action = desc->action;
 139         if (!action && !any_count)
 140                 goto out;
 141
 142         seq_printf(p, "%*d: ", prec, i);
 143         for_each_online_cpu(j)
 144                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 145         seq_printf(p, " %8s", desc->chip->name);
 146         seq_printf(p, "-%-8s", desc->name);
 147
 148         if (action) {
 149                 seq_printf(p, "  %s", action->name);
 150                 while ((action = action->next) != NULL)
 151                         seq_printf(p, ", %s", action->name);
 152         }
 153
 154         seq_putc(p, '\n');
 155 out:
 156         spin_unlock_irqrestore(&desc->lock, flags);
 157         return 0;
 158 }
 159
 160 /*
 161  * /proc/stat helpers
 162  */
 163 u64 arch_irq_stat_cpu(unsigned int cpu)
 164 {
 165         u64 sum = irq_stats(cpu)->__nmi_count;
 166
 167 #ifdef CONFIG_X86_LOCAL_APIC
 168         sum += irq_stats(cpu)->apic_timer_irqs;
 169         sum += irq_stats(cpu)->irq_spurious_count;
 170 #endif
 171         if (generic_interrupt_extension)
 172                 sum += irq_stats(cpu)->generic_irqs;
 173 #ifdef CONFIG_SMP
 174         sum += irq_stats(cpu)->irq_resched_count;
 175         sum += irq_stats(cpu)->irq_call_count;
 176         sum += irq_stats(cpu)->irq_tlb_count;
 177 #endif
 178 #ifdef CONFIG_X86_MCE
 179         sum += irq_stats(cpu)->irq_thermal_count;
 180 # ifdef CONFIG_X86_64
 181         sum += irq_stats(cpu)->irq_threshold_count;
 182 #endif
 183 #endif
 184         return sum;
 185 }
 186
 187 u64 arch_irq_stat(void)
 188 {
 189         u64 sum = atomic_read(&irq_err_count);
 190
 191 #ifdef CONFIG_X86_IO_APIC
 192         sum += atomic_read(&irq_mis_count);
 193 #endif
 194         return sum;
 195 }
 196
 197
 198 /*
 199  * do_IRQ handles all normal device IRQ's (the special
 200  * SMP cross-CPU interrupts have their own specific
 201  * handlers).
 202  */
 203 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 204 {
 205         struct pt_regs *old_regs = set_irq_regs(regs);
 206
 207         /* high bit used in ret_from_ code  */
 208         unsigned vector = ~regs->orig_ax;
 209         unsigned irq;
 210
 211         exit_idle();
 212         irq_enter();
 213
 214         irq = __get_cpu_var(vector_irq)[vector];
 215
 216         if (!handle_irq(irq, regs)) {
 217 #ifdef CONFIG_X86_64
 218                 if (!disable_apic)
 219                         ack_APIC_irq();
 220 #endif
 221
 222                 if (printk_ratelimit())
 223                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector (irq %d)\n",
 224                                __func__, smp_processor_id(), vector, irq);
 225         }
 226
 227         irq_exit();
 228
 229         set_irq_regs(old_regs);
 230         return 1;
 231 }
 232
 233 /*
 234  * Handler for GENERIC_INTERRUPT_VECTOR.
 235  */
 236 void smp_generic_interrupt(struct pt_regs *regs)
 237 {
 238         struct pt_regs *old_regs = set_irq_regs(regs);
 239
 240         ack_APIC_irq();
 241
 242         exit_idle();
 243
 244         irq_enter();
 245
 246         inc_irq_stat(generic_irqs);
 247
 248         if (generic_interrupt_extension)
 249                 generic_interrupt_extension();
 250
 251         irq_exit();
 252
 253         set_irq_regs(old_regs);
 254 }
 255
 256 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);