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 /*
  19  * 'what should we do if we get a hw irq event on an illegal vector'.
  20  * each architecture has to answer this themselves.
  21  */
  22 void ack_bad_irq(unsigned int irq)
  23 {
  24         printk(KERN_ERR "unexpected IRQ trap at vector %02x\n", irq);
  25
  26 #ifdef CONFIG_X86_LOCAL_APIC
  27         /*
  28          * Currently unexpected vectors happen only on SMP and APIC.
  29          * We _must_ ack these because every local APIC has only N
  30          * irq slots per priority level, and a 'hanging, unacked' IRQ
  31          * holds up an irq slot - in excessive cases (when multiple
  32          * unexpected vectors occur) that might lock up the APIC
  33          * completely.
  34          * But only ack when the APIC is enabled -AK
  35          */
  36         if (cpu_has_apic)
  37                 ack_APIC_irq();
  38 #endif
  39 }
  40
  41 #define irq_stats(x)            (&per_cpu(irq_stat, x))
  42 /*
  43  * /proc/interrupts printing:
  44  */
  45 static int show_other_interrupts(struct seq_file *p)
  46 {
  47         int j;
  48
  49         seq_printf(p, "NMI: ");
  50         for_each_online_cpu(j)
  51                 seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
  52         seq_printf(p, "  Non-maskable interrupts\n");
  53 #ifdef CONFIG_X86_LOCAL_APIC
  54         seq_printf(p, "LOC: ");
  55         for_each_online_cpu(j)
  56                 seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
  57         seq_printf(p, "  Local timer interrupts\n");
  58         seq_printf(p, "CNT: ");
  59         for_each_online_cpu(j)
  60                 seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
  61         seq_printf(p, "  Performance counter interrupts\n");
  62 #endif
  63 #ifdef CONFIG_SMP
  64         seq_printf(p, "RES: ");
  65         for_each_online_cpu(j)
  66                 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
  67         seq_printf(p, "  Rescheduling interrupts\n");
  68         seq_printf(p, "CAL: ");
  69         for_each_online_cpu(j)
  70                 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
  71         seq_printf(p, "  Function call interrupts\n");
  72         seq_printf(p, "TLB: ");
  73         for_each_online_cpu(j)
  74                 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
  75         seq_printf(p, "  TLB shootdowns\n");
  76 #endif
  77 #ifdef CONFIG_X86_MCE
  78         seq_printf(p, "TRM: ");
  79         for_each_online_cpu(j)
  80                 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
  81         seq_printf(p, "  Thermal event interrupts\n");
  82 # ifdef CONFIG_X86_64
  83         seq_printf(p, "THR: ");
  84         for_each_online_cpu(j)
  85                 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
  86         seq_printf(p, "  Threshold APIC interrupts\n");
  87 # endif
  88 #endif
  89 #ifdef CONFIG_X86_LOCAL_APIC
  90         seq_printf(p, "SPU: ");
  91         for_each_online_cpu(j)
  92                 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
  93         seq_printf(p, "  Spurious interrupts\n");
  94 #endif
  95         seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
  96 #if defined(CONFIG_X86_IO_APIC)
  97         seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count));
  98 #endif
  99         return 0;
 100 }
 101
 102 int show_interrupts(struct seq_file *p, void *v)
 103 {
 104         unsigned long flags, any_count = 0;
 105         int i = *(loff_t *) v, j;
 106         struct irqaction *action;
 107         struct irq_desc *desc;
 108
 109         if (i > nr_irqs)
 110                 return 0;
 111
 112         if (i == nr_irqs)
 113                 return show_other_interrupts(p);
 114
 115         /* print header */
 116         if (i == 0) {
 117                 seq_printf(p, "           ");
 118                 for_each_online_cpu(j)
 119                         seq_printf(p, "CPU%-8d", j);
 120                 seq_putc(p, '\n');
 121         }
 122
 123         desc = irq_to_desc(i);
 124         if (!desc)
 125                 return 0;
 126
 127         spin_lock_irqsave(&desc->lock, flags);
 128 #ifndef CONFIG_SMP
 129         any_count = kstat_irqs(i);
 130 #else
 131         for_each_online_cpu(j)
 132                 any_count |= kstat_irqs_cpu(i, j);
 133 #endif
 134         action = desc->action;
 135         if (!action && !any_count)
 136                 goto out;
 137
 138         seq_printf(p, "%3d: ", i);
 139 #ifndef CONFIG_SMP
 140         seq_printf(p, "%10u ", kstat_irqs(i));
 141 #else
 142         for_each_online_cpu(j)
 143                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 144 #endif
 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)->apic_perf_irqs;
 170 #endif
 171 #ifdef CONFIG_SMP
 172         sum += irq_stats(cpu)->irq_resched_count;
 173         sum += irq_stats(cpu)->irq_call_count;
 174         sum += irq_stats(cpu)->irq_tlb_count;
 175 #endif
 176 #ifdef CONFIG_X86_MCE
 177         sum += irq_stats(cpu)->irq_thermal_count;
 178 # ifdef CONFIG_X86_64
 179         sum += irq_stats(cpu)->irq_threshold_count;
 180 #endif
 181 #endif
 182 #ifdef CONFIG_X86_LOCAL_APIC
 183         sum += irq_stats(cpu)->irq_spurious_count;
 184 #endif
 185         return sum;
 186 }
 187
 188 u64 arch_irq_stat(void)
 189 {
 190         u64 sum = atomic_read(&irq_err_count);
 191
 192 #ifdef CONFIG_X86_IO_APIC
 193         sum += atomic_read(&irq_mis_count);
 194 #endif
 195         return sum;
 196 }
 197
 198
 199 /*
 200  * do_IRQ handles all normal device IRQ's (the special
 201  * SMP cross-CPU interrupts have their own specific
 202  * handlers).
 203  */
 204 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 205 {
 206         struct pt_regs *old_regs = set_irq_regs(regs);
 207
 208         /* high bit used in ret_from_ code  */
 209         unsigned vector = ~regs->orig_ax;
 210         unsigned irq;
 211
 212         exit_idle();
 213         irq_enter();
 214
 215         irq = __get_cpu_var(vector_irq)[vector];
 216
 217         if (!handle_irq(irq, regs)) {
 218 #ifdef CONFIG_X86_64
 219                 if (!disable_apic)
 220                         ack_APIC_irq();
 221 #endif
 222
 223                 if (printk_ratelimit())
 224                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector (irq %d)\n",
 225                                __func__, smp_processor_id(), vector, irq);
 226         }
 227
 228         irq_exit();
 229
 230         set_irq_regs(old_regs);
 231         return 1;
 232 }
 233
 234 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);