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
  16 atomic_t irq_err_count;
  17
  18 /* Function pointer for generic interrupt vector handling */
  19 void (*generic_interrupt_extension)(void) = NULL;
  20
  21 /*
  22  * 'what should we do if we get a hw irq event on an illegal vector'.
  23  * each architecture has to answer this themselves.
  24  */
  25 void ack_bad_irq(unsigned int irq)
  26 {
  27         printk(KERN_ERR "unexpected IRQ trap at vector %02x\n", irq);
  28
  29 #ifdef CONFIG_X86_LOCAL_APIC
  30         /*
  31          * Currently unexpected vectors happen only on SMP and APIC.
  32          * We _must_ ack these because every local APIC has only N
  33          * irq slots per priority level, and a 'hanging, unacked' IRQ
  34          * holds up an irq slot - in excessive cases (when multiple
  35          * unexpected vectors occur) that might lock up the APIC
  36          * completely.
  37          * But only ack when the APIC is enabled -AK
  38          */
  39         if (cpu_has_apic)
  40                 ack_APIC_irq();
  41 #endif
  42 }
  43
  44 #define irq_stats(x)            (&per_cpu(irq_stat, x))
  45 /*
  46  * /proc/interrupts printing:
  47  */
  48 static int show_other_interrupts(struct seq_file *p, int prec)
  49 {
  50         int j;
  51
  52         seq_printf(p, "%*s: ", prec, "NMI");
  53         for_each_online_cpu(j)
  54                 seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
  55         seq_printf(p, "  Non-maskable interrupts\n");
  56 #ifdef CONFIG_X86_LOCAL_APIC
  57         seq_printf(p, "%*s: ", prec, "LOC");
  58         for_each_online_cpu(j)
  59                 seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
  60         seq_printf(p, "  Local timer interrupts\n");
  61 #endif
  62         if (generic_interrupt_extension) {
  63                 seq_printf(p, "PLT: ");
  64                 for_each_online_cpu(j)
  65                         seq_printf(p, "%10u ", irq_stats(j)->generic_irqs);
  66                 seq_printf(p, "  Platform interrupts\n");
  67         }
  68 #ifdef CONFIG_SMP
  69         seq_printf(p, "%*s: ", prec, "RES");
  70         for_each_online_cpu(j)
  71                 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
  72         seq_printf(p, "  Rescheduling interrupts\n");
  73         seq_printf(p, "%*s: ", prec, "CAL");
  74         for_each_online_cpu(j)
  75                 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
  76         seq_printf(p, "  Function call interrupts\n");
  77         seq_printf(p, "%*s: ", prec, "TLB");
  78         for_each_online_cpu(j)
  79                 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
  80         seq_printf(p, "  TLB shootdowns\n");
  81 #endif
  82 #ifdef CONFIG_X86_MCE
  83         seq_printf(p, "%*s: ", prec, "TRM");
  84         for_each_online_cpu(j)
  85                 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
  86         seq_printf(p, "  Thermal event interrupts\n");
  87 # ifdef CONFIG_X86_64
  88         seq_printf(p, "%*s: ", prec, "THR");
  89         for_each_online_cpu(j)
  90                 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
  91         seq_printf(p, "  Threshold APIC interrupts\n");
  92 # endif
  93 #endif
  94 #ifdef CONFIG_X86_LOCAL_APIC
  95         seq_printf(p, "%*s: ", prec, "SPU");
  96         for_each_online_cpu(j)
  97                 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
  98         seq_printf(p, "  Spurious interrupts\n");
  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 #ifndef CONFIG_SMP
 137         any_count = kstat_irqs(i);
 138 #else
 139         for_each_online_cpu(j)
 140                 any_count |= kstat_irqs_cpu(i, j);
 141 #endif
 142         action = desc->action;
 143         if (!action && !any_count)
 144                 goto out;
 145
 146         seq_printf(p, "%*d: ", prec, i);
 147 #ifndef CONFIG_SMP
 148         seq_printf(p, "%10u ", kstat_irqs(i));
 149 #else
 150         for_each_online_cpu(j)
 151                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 152 #endif
 153         seq_printf(p, " %8s", desc->chip->name);
 154         seq_printf(p, "-%-8s", desc->name);
 155
 156         if (action) {
 157                 seq_printf(p, "  %s", action->name);
 158                 while ((action = action->next) != NULL)
 159                         seq_printf(p, ", %s", action->name);
 160         }
 161
 162         seq_putc(p, '\n');
 163 out:
 164         spin_unlock_irqrestore(&desc->lock, flags);
 165         return 0;
 166 }
 167
 168 /*
 169  * /proc/stat helpers
 170  */
 171 u64 arch_irq_stat_cpu(unsigned int cpu)
 172 {
 173         u64 sum = irq_stats(cpu)->__nmi_count;
 174
 175 #ifdef CONFIG_X86_LOCAL_APIC
 176         sum += irq_stats(cpu)->apic_timer_irqs;
 177 #endif
 178         if (generic_interrupt_extension)
 179                 sum += irq_stats(cpu)->generic_irqs;
 180 #ifdef CONFIG_SMP
 181         sum += irq_stats(cpu)->irq_resched_count;
 182         sum += irq_stats(cpu)->irq_call_count;
 183         sum += irq_stats(cpu)->irq_tlb_count;
 184 #endif
 185 #ifdef CONFIG_X86_MCE
 186         sum += irq_stats(cpu)->irq_thermal_count;
 187 # ifdef CONFIG_X86_64
 188         sum += irq_stats(cpu)->irq_threshold_count;
 189 #endif
 190 #endif
 191 #ifdef CONFIG_X86_LOCAL_APIC
 192         sum += irq_stats(cpu)->irq_spurious_count;
 193 #endif
 194         return sum;
 195 }
 196
 197 u64 arch_irq_stat(void)
 198 {
 199         u64 sum = atomic_read(&irq_err_count);
 200
 201 #ifdef CONFIG_X86_IO_APIC
 202         sum += atomic_read(&irq_mis_count);
 203 #endif
 204         return sum;
 205 }
 206
 207
 208 /*
 209  * do_IRQ handles all normal device IRQ's (the special
 210  * SMP cross-CPU interrupts have their own specific
 211  * handlers).
 212  */
 213 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 214 {
 215         struct pt_regs *old_regs = set_irq_regs(regs);
 216
 217         /* high bit used in ret_from_ code  */
 218         unsigned vector = ~regs->orig_ax;
 219         unsigned irq;
 220
 221         exit_idle();
 222         irq_enter();
 223
 224         irq = __get_cpu_var(vector_irq)[vector];
 225
 226         if (!handle_irq(irq, regs)) {
 227 #ifdef CONFIG_X86_64
 228                 if (!disable_apic)
 229                         ack_APIC_irq();
 230 #endif
 231
 232                 if (printk_ratelimit())
 233                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector (irq %d)\n",
 234                                __func__, smp_processor_id(), vector, irq);
 235         }
 236
 237         irq_exit();
 238
 239         set_irq_regs(old_regs);
 240         return 1;
 241 }
 242
 243 /*
 244  * Handler for GENERIC_INTERRUPT_VECTOR.
 245  */
 246 void smp_generic_interrupt(struct pt_regs *regs)
 247 {
 248         struct pt_regs *old_regs = set_irq_regs(regs);
 249
 250         ack_APIC_irq();
 251
 252         exit_idle();
 253
 254         irq_enter();
 255
 256         inc_irq_stat(generic_irqs);
 257
 258         if (generic_interrupt_extension)
 259                 generic_interrupt_extension();
 260
 261         irq_exit();
 262
 263         set_irq_regs(old_regs);
 264 }
 265
 266 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);