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
  62         seq_printf(p, "%*s: ", prec, "SPU");
  63         for_each_online_cpu(j)
  64                 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
  65         seq_printf(p, "  Spurious interrupts\n");
  66 #endif
  67         if (generic_interrupt_extension) {
  68                 seq_printf(p, "%*s: ", prec, "PLT");
  69                 for_each_online_cpu(j)
  70                         seq_printf(p, "%10u ", irq_stats(j)->generic_irqs);
  71                 seq_printf(p, "  Platform interrupts\n");
  72         }
  73 #ifdef CONFIG_SMP
  74         seq_printf(p, "%*s: ", prec, "RES");
  75         for_each_online_cpu(j)
  76                 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
  77         seq_printf(p, "  Rescheduling interrupts\n");
  78         seq_printf(p, "%*s: ", prec, "CAL");
  79         for_each_online_cpu(j)
  80                 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
  81         seq_printf(p, "  Function call interrupts\n");
  82         seq_printf(p, "%*s: ", prec, "TLB");
  83         for_each_online_cpu(j)
  84                 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
  85         seq_printf(p, "  TLB shootdowns\n");
  86 #endif
  87 #ifdef CONFIG_X86_MCE
  88         seq_printf(p, "%*s: ", prec, "TRM");
  89         for_each_online_cpu(j)
  90                 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
  91         seq_printf(p, "  Thermal event interrupts\n");
  92 # ifdef CONFIG_X86_64
  93         seq_printf(p, "%*s: ", prec, "THR");
  94         for_each_online_cpu(j)
  95                 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
  96         seq_printf(p, "  Threshold APIC interrupts\n");
  97 # endif
  98 #endif
  99         seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
 100 #if defined(CONFIG_X86_IO_APIC)
 101         seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
 102 #endif
 103         return 0;
 104 }
 105
 106 int show_interrupts(struct seq_file *p, void *v)
 107 {
 108         unsigned long flags, any_count = 0;
 109         int i = *(loff_t *) v, j, prec;
 110         struct irqaction *action;
 111         struct irq_desc *desc;
 112
 113         if (i > nr_irqs)
 114                 return 0;
 115
 116         for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
 117                 j *= 10;
 118
 119         if (i == nr_irqs)
 120                 return show_other_interrupts(p, prec);
 121
 122         /* print header */
 123         if (i == 0) {
 124                 seq_printf(p, "%*s", prec + 8, "");
 125                 for_each_online_cpu(j)
 126                         seq_printf(p, "CPU%-8d", j);
 127                 seq_putc(p, '\n');
 128         }
 129
 130         desc = irq_to_desc(i);
 131         if (!desc)
 132                 return 0;
 133
 134         spin_lock_irqsave(&desc->lock, flags);
 135         for_each_online_cpu(j)
 136                 any_count |= kstat_irqs_cpu(i, j);
 137         action = desc->action;
 138         if (!action && !any_count)
 139                 goto out;
 140
 141         seq_printf(p, "%*d: ", prec, i);
 142         for_each_online_cpu(j)
 143                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 144         seq_printf(p, " %8s", desc->chip->name);
 145         seq_printf(p, "-%-8s", desc->name);
 146
 147         if (action) {
 148                 seq_printf(p, "  %s", action->name);
 149                 while ((action = action->next) != NULL)
 150                         seq_printf(p, ", %s", action->name);
 151         }
 152
 153         seq_putc(p, '\n');
 154 out:
 155         spin_unlock_irqrestore(&desc->lock, flags);
 156         return 0;
 157 }
 158
 159 /*
 160  * /proc/stat helpers
 161  */
 162 u64 arch_irq_stat_cpu(unsigned int cpu)
 163 {
 164         u64 sum = irq_stats(cpu)->__nmi_count;
 165
 166 #ifdef CONFIG_X86_LOCAL_APIC
 167         sum += irq_stats(cpu)->apic_timer_irqs;
 168         sum += irq_stats(cpu)->irq_spurious_count;
 169 #endif
 170         if (generic_interrupt_extension)
 171                 sum += irq_stats(cpu)->generic_irqs;
 172 #ifdef CONFIG_SMP
 173         sum += irq_stats(cpu)->irq_resched_count;
 174         sum += irq_stats(cpu)->irq_call_count;
 175         sum += irq_stats(cpu)->irq_tlb_count;
 176 #endif
 177 #ifdef CONFIG_X86_MCE
 178         sum += irq_stats(cpu)->irq_thermal_count;
 179 # ifdef CONFIG_X86_64
 180         sum += irq_stats(cpu)->irq_threshold_count;
 181 #endif
 182 #endif
 183         return sum;
 184 }
 185
 186 u64 arch_irq_stat(void)
 187 {
 188         u64 sum = atomic_read(&irq_err_count);
 189
 190 #ifdef CONFIG_X86_IO_APIC
 191         sum += atomic_read(&irq_mis_count);
 192 #endif
 193         return sum;
 194 }
 195
 196
 197 /*
 198  * do_IRQ handles all normal device IRQ's (the special
 199  * SMP cross-CPU interrupts have their own specific
 200  * handlers).
 201  */
 202 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 203 {
 204         struct pt_regs *old_regs = set_irq_regs(regs);
 205
 206         /* high bit used in ret_from_ code  */
 207         unsigned vector = ~regs->orig_ax;
 208         unsigned irq;
 209
 210         exit_idle();
 211         irq_enter();
 212
 213         irq = __get_cpu_var(vector_irq)[vector];
 214
 215         if (!handle_irq(irq, regs)) {
 216 #ifdef CONFIG_X86_64
 217                 if (!disable_apic)
 218                         ack_APIC_irq();
 219 #endif
 220
 221                 if (printk_ratelimit())
 222                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector (irq %d)\n",
 223                                __func__, smp_processor_id(), vector, irq);
 224         }
 225
 226         irq_exit();
 227
 228         set_irq_regs(old_regs);
 229         return 1;
 230 }
 231
 232 /*
 233  * Handler for GENERIC_INTERRUPT_VECTOR.
 234  */
 235 void smp_generic_interrupt(struct pt_regs *regs)
 236 {
 237         struct pt_regs *old_regs = set_irq_regs(regs);
 238
 239         ack_APIC_irq();
 240
 241         exit_idle();
 242
 243         irq_enter();
 244
 245         inc_irq_stat(generic_irqs);
 246
 247         if (generic_interrupt_extension)
 248                 generic_interrupt_extension();
 249
 250         irq_exit();
 251
 252         set_irq_regs(old_regs);
 253 }
 254
 255 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);