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)
  49 {
  50         int j;
  51
  52         seq_printf(p, "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, "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, "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, "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, "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, "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, "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, "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, "ERR: %10u\n", atomic_read(&irq_err_count));
 101 #if defined(CONFIG_X86_IO_APIC)
 102         seq_printf(p, "MIS: %10u\n", 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;
 111         struct irqaction *action;
 112         struct irq_desc *desc;
 113
 114         if (i > nr_irqs)
 115                 return 0;
 116
 117         if (i == nr_irqs)
 118                 return show_other_interrupts(p);
 119
 120         /* print header */
 121         if (i == 0) {
 122                 seq_printf(p, "           ");
 123                 for_each_online_cpu(j)
 124                         seq_printf(p, "CPU%-8d", j);
 125                 seq_putc(p, '\n');
 126         }
 127
 128         desc = irq_to_desc(i);
 129         if (!desc)
 130                 return 0;
 131
 132         spin_lock_irqsave(&desc->lock, flags);
 133 #ifndef CONFIG_SMP
 134         any_count = kstat_irqs(i);
 135 #else
 136         for_each_online_cpu(j)
 137                 any_count |= kstat_irqs_cpu(i, j);
 138 #endif
 139         action = desc->action;
 140         if (!action && !any_count)
 141                 goto out;
 142
 143         seq_printf(p, "%3d: ", i);
 144 #ifndef CONFIG_SMP
 145         seq_printf(p, "%10u ", kstat_irqs(i));
 146 #else
 147         for_each_online_cpu(j)
 148                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 149 #endif
 150         seq_printf(p, " %8s", desc->chip->name);
 151         seq_printf(p, "-%-8s", desc->name);
 152
 153         if (action) {
 154                 seq_printf(p, "  %s", action->name);
 155                 while ((action = action->next) != NULL)
 156                         seq_printf(p, ", %s", action->name);
 157         }
 158
 159         seq_putc(p, '\n');
 160 out:
 161         spin_unlock_irqrestore(&desc->lock, flags);
 162         return 0;
 163 }
 164
 165 /*
 166  * /proc/stat helpers
 167  */
 168 u64 arch_irq_stat_cpu(unsigned int cpu)
 169 {
 170         u64 sum = irq_stats(cpu)->__nmi_count;
 171
 172 #ifdef CONFIG_X86_LOCAL_APIC
 173         sum += irq_stats(cpu)->apic_timer_irqs;
 174 #endif
 175         if (generic_interrupt_extension)
 176                 sum += irq_stats(cpu)->generic_irqs;
 177 #ifdef CONFIG_SMP
 178         sum += irq_stats(cpu)->irq_resched_count;
 179         sum += irq_stats(cpu)->irq_call_count;
 180         sum += irq_stats(cpu)->irq_tlb_count;
 181 #endif
 182 #ifdef CONFIG_X86_MCE
 183         sum += irq_stats(cpu)->irq_thermal_count;
 184 # ifdef CONFIG_X86_64
 185         sum += irq_stats(cpu)->irq_threshold_count;
 186 #endif
 187 #endif
 188 #ifdef CONFIG_X86_LOCAL_APIC
 189         sum += irq_stats(cpu)->irq_spurious_count;
 190 #endif
 191         return sum;
 192 }
 193
 194 u64 arch_irq_stat(void)
 195 {
 196         u64 sum = atomic_read(&irq_err_count);
 197
 198 #ifdef CONFIG_X86_IO_APIC
 199         sum += atomic_read(&irq_mis_count);
 200 #endif
 201         return sum;
 202 }
 203
 204
 205 /*
 206  * do_IRQ handles all normal device IRQ's (the special
 207  * SMP cross-CPU interrupts have their own specific
 208  * handlers).
 209  */
 210 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 211 {
 212         struct pt_regs *old_regs = set_irq_regs(regs);
 213
 214         /* high bit used in ret_from_ code  */
 215         unsigned vector = ~regs->orig_ax;
 216         unsigned irq;
 217
 218         exit_idle();
 219         irq_enter();
 220
 221         irq = __get_cpu_var(vector_irq)[vector];
 222
 223         if (!handle_irq(irq, regs)) {
 224 #ifdef CONFIG_X86_64
 225                 if (!disable_apic)
 226                         ack_APIC_irq();
 227 #endif
 228
 229                 if (printk_ratelimit())
 230                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector (irq %d)\n",
 231                                __func__, smp_processor_id(), vector, irq);
 232         }
 233
 234         irq_exit();
 235
 236         set_irq_regs(old_regs);
 237         return 1;
 238 }
 239
 240 /*
 241  * Handler for GENERIC_INTERRUPT_VECTOR.
 242  */
 243 void smp_generic_interrupt(struct pt_regs *regs)
 244 {
 245         struct pt_regs *old_regs = set_irq_regs(regs);
 246
 247         ack_APIC_irq();
 248
 249         exit_idle();
 250
 251         irq_enter();
 252
 253         inc_irq_stat(generic_irqs);
 254
 255         if (generic_interrupt_extension)
 256                 generic_interrupt_extension();
 257
 258         irq_exit();
 259
 260         set_irq_regs(old_regs);
 261 }
 262
 263 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);