git.oblomov.eu Git - linux-2.6/blob - 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         if (printk_ratelimit())
  28                 pr_err("unexpected IRQ trap at vector %02x\n", irq);
  29
  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         ack_APIC_irq();
  40 }
  41
  42 #define irq_stats(x)            (&per_cpu(irq_stat, x))
  43 /*
  44  * /proc/interrupts printing:
  45  */
  46 static int show_other_interrupts(struct seq_file *p, int prec)
  47 {
  48         int j;
  49
  50         seq_printf(p, "%*s: ", prec, "NMI");
  51         for_each_online_cpu(j)
  52                 seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
  53         seq_printf(p, "  Non-maskable interrupts\n");
  54 #ifdef CONFIG_X86_LOCAL_APIC
  55         seq_printf(p, "%*s: ", prec, "LOC");
  56         for_each_online_cpu(j)
  57                 seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
  58         seq_printf(p, "  Local timer interrupts\n");
  59
  60         seq_printf(p, "%*s: ", prec, "SPU");
  61         for_each_online_cpu(j)
  62                 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
  63         seq_printf(p, "  Spurious interrupts\n");
  64 #endif
  65         if (generic_interrupt_extension) {
  66                 seq_printf(p, "%*s: ", prec, "PLT");
  67                 for_each_online_cpu(j)
  68                         seq_printf(p, "%10u ", irq_stats(j)->generic_irqs);
  69                 seq_printf(p, "  Platform interrupts\n");
  70         }
  71 #ifdef CONFIG_SMP
  72         seq_printf(p, "%*s: ", prec, "RES");
  73         for_each_online_cpu(j)
  74                 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
  75         seq_printf(p, "  Rescheduling interrupts\n");
  76         seq_printf(p, "%*s: ", prec, "CAL");
  77         for_each_online_cpu(j)
  78                 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
  79         seq_printf(p, "  Function call interrupts\n");
  80         seq_printf(p, "%*s: ", prec, "TLB");
  81         for_each_online_cpu(j)
  82                 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
  83         seq_printf(p, "  TLB shootdowns\n");
  84 #endif
  85 #ifdef CONFIG_X86_MCE
  86         seq_printf(p, "%*s: ", prec, "TRM");
  87         for_each_online_cpu(j)
  88                 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
  89         seq_printf(p, "  Thermal event interrupts\n");
  90 # ifdef CONFIG_X86_MCE_THRESHOLD
  91         seq_printf(p, "%*s: ", prec, "THR");
  92         for_each_online_cpu(j)
  93                 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
  94         seq_printf(p, "  Threshold APIC interrupts\n");
  95 # endif
  96 #endif
  97         seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
  98 #if defined(CONFIG_X86_IO_APIC)
  99         seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
 100 #endif
 101         return 0;
 102 }
 103
 104 int show_interrupts(struct seq_file *p, void *v)
 105 {
 106         unsigned long flags, any_count = 0;
 107         int i = *(loff_t *) v, j, prec;
 108         struct irqaction *action;
 109         struct irq_desc *desc;
 110
 111         if (i > nr_irqs)
 112                 return 0;
 113
 114         for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
 115                 j *= 10;
 116
 117         if (i == nr_irqs)
 118                 return show_other_interrupts(p, prec);
 119
 120         /* print header */
 121         if (i == 0) {
 122                 seq_printf(p, "%*s", prec + 8, "");
 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         for_each_online_cpu(j)
 134                 any_count |= kstat_irqs_cpu(i, j);
 135         action = desc->action;
 136         if (!action && !any_count)
 137                 goto out;
 138
 139         seq_printf(p, "%*d: ", prec, i);
 140         for_each_online_cpu(j)
 141                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 142         seq_printf(p, " %8s", desc->chip->name);
 143         seq_printf(p, "-%-8s", desc->name);
 144
 145         if (action) {
 146                 seq_printf(p, "  %s", action->name);
 147                 while ((action = action->next) != NULL)
 148                         seq_printf(p, ", %s", action->name);
 149         }
 150
 151         seq_putc(p, '\n');
 152 out:
 153         spin_unlock_irqrestore(&desc->lock, flags);
 154         return 0;
 155 }
 156
 157 /*
 158  * /proc/stat helpers
 159  */
 160 u64 arch_irq_stat_cpu(unsigned int cpu)
 161 {
 162         u64 sum = irq_stats(cpu)->__nmi_count;
 163
 164 #ifdef CONFIG_X86_LOCAL_APIC
 165         sum += irq_stats(cpu)->apic_timer_irqs;
 166         sum += irq_stats(cpu)->irq_spurious_count;
 167 #endif
 168         if (generic_interrupt_extension)
 169                 sum += irq_stats(cpu)->generic_irqs;
 170 #ifdef CONFIG_SMP
 171         sum += irq_stats(cpu)->irq_resched_count;
 172         sum += irq_stats(cpu)->irq_call_count;
 173         sum += irq_stats(cpu)->irq_tlb_count;
 174 #endif
 175 #ifdef CONFIG_X86_MCE
 176         sum += irq_stats(cpu)->irq_thermal_count;
 177 # ifdef CONFIG_X86_MCE_THRESHOLD
 178         sum += irq_stats(cpu)->irq_threshold_count;
 179 # endif
 180 #endif
 181         return sum;
 182 }
 183
 184 u64 arch_irq_stat(void)
 185 {
 186         u64 sum = atomic_read(&irq_err_count);
 187
 188 #ifdef CONFIG_X86_IO_APIC
 189         sum += atomic_read(&irq_mis_count);
 190 #endif
 191         return sum;
 192 }
 193
 194
 195 /*
 196  * do_IRQ handles all normal device IRQ's (the special
 197  * SMP cross-CPU interrupts have their own specific
 198  * handlers).
 199  */
 200 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
 201 {
 202         struct pt_regs *old_regs = set_irq_regs(regs);
 203
 204         /* high bit used in ret_from_ code  */
 205         unsigned vector = ~regs->orig_ax;
 206         unsigned irq;
 207
 208         exit_idle();
 209         irq_enter();
 210
 211         irq = __get_cpu_var(vector_irq)[vector];
 212
 213         if (!handle_irq(irq, regs)) {
 214                 ack_APIC_irq();
 215
 216                 if (printk_ratelimit())
 217                         pr_emerg("%s: %d.%d No irq handler for vector (irq %d)\n",
 218                                 __func__, smp_processor_id(), vector, irq);
 219         }
 220
 221         irq_exit();
 222
 223         set_irq_regs(old_regs);
 224         return 1;
 225 }
 226
 227 /*
 228  * Handler for GENERIC_INTERRUPT_VECTOR.
 229  */
 230 void smp_generic_interrupt(struct pt_regs *regs)
 231 {
 232         struct pt_regs *old_regs = set_irq_regs(regs);
 233
 234         ack_APIC_irq();
 235
 236         exit_idle();
 237
 238         irq_enter();
 239
 240         inc_irq_stat(generic_irqs);
 241
 242         if (generic_interrupt_extension)
 243                 generic_interrupt_extension();
 244
 245         irq_exit();
 246
 247         set_irq_regs(old_regs);
 248 }
 249
 250 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);