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 #endif
  59 #ifdef CONFIG_SMP
  60         seq_printf(p, "RES: ");
  61         for_each_online_cpu(j)
  62                 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
  63         seq_printf(p, "  Rescheduling interrupts\n");
  64         seq_printf(p, "CAL: ");
  65         for_each_online_cpu(j)
  66                 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
  67         seq_printf(p, "  Function call interrupts\n");
  68         seq_printf(p, "TLB: ");
  69         for_each_online_cpu(j)
  70                 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
  71         seq_printf(p, "  TLB shootdowns\n");
  72 #endif
  73 #ifdef CONFIG_X86_MCE
  74         seq_printf(p, "TRM: ");
  75         for_each_online_cpu(j)
  76                 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
  77         seq_printf(p, "  Thermal event interrupts\n");
  78 # ifdef CONFIG_X86_64
  79         seq_printf(p, "THR: ");
  80         for_each_online_cpu(j)
  81                 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
  82         seq_printf(p, "  Threshold APIC interrupts\n");
  83 # endif
  84 #endif
  85 #ifdef CONFIG_X86_LOCAL_APIC
  86         seq_printf(p, "SPU: ");
  87         for_each_online_cpu(j)
  88                 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
  89         seq_printf(p, "  Spurious interrupts\n");
  90 #endif
  91         seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
  92 #if defined(CONFIG_X86_IO_APIC)
  93         seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count));
  94 #endif
  95         return 0;
  96 }
  97
  98 int show_interrupts(struct seq_file *p, void *v)
  99 {
 100         unsigned long flags, any_count = 0;
 101         int i = *(loff_t *) v, j;
 102         struct irqaction *action;
 103         struct irq_desc *desc;
 104
 105         if (i > nr_irqs)
 106                 return 0;
 107
 108         if (i == nr_irqs)
 109                 return show_other_interrupts(p);
 110
 111         /* print header */
 112         if (i == 0) {
 113                 seq_printf(p, "           ");
 114                 for_each_online_cpu(j)
 115                         seq_printf(p, "CPU%-8d", j);
 116                 seq_putc(p, '\n');
 117         }
 118
 119         desc = irq_to_desc(i);
 120         if (!desc)
 121                 return 0;
 122
 123         spin_lock_irqsave(&desc->lock, flags);
 124 #ifndef CONFIG_SMP
 125         any_count = kstat_irqs(i);
 126 #else
 127         for_each_online_cpu(j)
 128                 any_count |= kstat_irqs_cpu(i, j);
 129 #endif
 130         action = desc->action;
 131         if (!action && !any_count)
 132                 goto out;
 133
 134         seq_printf(p, "%3d: ", i);
 135 #ifndef CONFIG_SMP
 136         seq_printf(p, "%10u ", kstat_irqs(i));
 137 #else
 138         for_each_online_cpu(j)
 139                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 140 #endif
 141         seq_printf(p, " %8s", desc->chip->name);
 142         seq_printf(p, "-%-8s", desc->name);
 143
 144         if (action) {
 145                 seq_printf(p, "  %s", action->name);
 146                 while ((action = action->next) != NULL)
 147                         seq_printf(p, ", %s", action->name);
 148         }
 149
 150         seq_putc(p, '\n');
 151 out:
 152         spin_unlock_irqrestore(&desc->lock, flags);
 153         return 0;
 154 }
 155
 156 /*
 157  * /proc/stat helpers
 158  */
 159 u64 arch_irq_stat_cpu(unsigned int cpu)
 160 {
 161         u64 sum = irq_stats(cpu)->__nmi_count;
 162
 163 #ifdef CONFIG_X86_LOCAL_APIC
 164         sum += irq_stats(cpu)->apic_timer_irqs;
 165 #endif
 166 #ifdef CONFIG_SMP
 167         sum += irq_stats(cpu)->irq_resched_count;
 168         sum += irq_stats(cpu)->irq_call_count;
 169         sum += irq_stats(cpu)->irq_tlb_count;
 170 #endif
 171 #ifdef CONFIG_X86_MCE
 172         sum += irq_stats(cpu)->irq_thermal_count;
 173 # ifdef CONFIG_X86_64
 174         sum += irq_stats(cpu)->irq_threshold_count;
 175 #endif
 176 #endif
 177 #ifdef CONFIG_X86_LOCAL_APIC
 178         sum += irq_stats(cpu)->irq_spurious_count;
 179 #endif
 180         return sum;
 181 }
 182
 183 u64 arch_irq_stat(void)
 184 {
 185         u64 sum = atomic_read(&irq_err_count);
 186
 187 #ifdef CONFIG_X86_IO_APIC
 188         sum += atomic_read(&irq_mis_count);
 189 #endif
 190         return sum;
 191 }
 192
 193
 194 /*
 195  * do_IRQ handles all normal device IRQ's (the special
 196  * SMP cross-CPU interrupts have their own specific
 197  * handlers).
 198  */
 199 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 200 {
 201         struct pt_regs *old_regs = set_irq_regs(regs);
 202
 203         /* high bit used in ret_from_ code  */
 204         unsigned vector = ~regs->orig_ax;
 205         unsigned irq;
 206
 207         exit_idle();
 208         irq_enter();
 209
 210         irq = __get_cpu_var(vector_irq)[vector];
 211
 212         if (!handle_irq(irq, regs)) {
 213 #ifdef CONFIG_X86_64
 214                 if (!disable_apic)
 215                         ack_APIC_irq();
 216 #endif
 217
 218                 if (printk_ratelimit())
 219                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector (irq %d)\n",
 220                                __func__, smp_processor_id(), vector, irq);
 221         }
 222
 223         irq_exit();
 224
 225         set_irq_regs(old_regs);
 226         return 1;
 227 }
 228
 229 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);