summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/irq_64.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/irq_64.c')
-rw-r--r--arch/x86/kernel/irq_64.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
new file mode 100644
index 000000000000..39cb3fa83ebb
--- /dev/null
+++ b/arch/x86/kernel/irq_64.c
@@ -0,0 +1,213 @@
+/*
+ * linux/arch/x86_64/kernel/irq.c
+ *
+ * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains the lowest level x86_64-specific interrupt
+ * entry and irq statistics code. All the remaining irq logic is
+ * done by the generic kernel/irq/ code and in the
+ * x86_64-specific irq controller code. (e.g. i8259.c and
+ * io_apic.c.)
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <asm/uaccess.h>
+#include <asm/io_apic.h>
+#include <asm/idle.h>
+#include <asm/smp.h>
+
+atomic_t irq_err_count;
+
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+/*
+ * Probabilistic stack overflow check:
+ *
+ * Only check the stack in process context, because everything else
+ * runs on the big interrupt stacks. Checking reliably is too expensive,
+ * so we just check from interrupts.
+ */
+static inline void stack_overflow_check(struct pt_regs *regs)
+{
+ u64 curbase = (u64)task_stack_page(current);
+ static unsigned long warned = -60*HZ;
+
+ if (regs->rsp >= curbase && regs->rsp <= curbase + THREAD_SIZE &&
+ regs->rsp < curbase + sizeof(struct thread_info) + 128 &&
+ time_after(jiffies, warned + 60*HZ)) {
+ printk("do_IRQ: %s near stack overflow (cur:%Lx,rsp:%lx)\n",
+ current->comm, curbase, regs->rsp);
+ show_stack(NULL,NULL);
+ warned = jiffies;
+ }
+}
+#endif
+
+/*
+ * Generic, controller-independent functions:
+ */
+
+int show_interrupts(struct seq_file *p, void *v)
+{
+ int i = *(loff_t *) v, j;
+ struct irqaction * action;
+ unsigned long flags;
+
+ if (i == 0) {
+ seq_printf(p, " ");
+ for_each_online_cpu(j)
+ seq_printf(p, "CPU%-8d",j);
+ seq_putc(p, '\n');
+ }
+
+ if (i < NR_IRQS) {
+ spin_lock_irqsave(&irq_desc[i].lock, flags);
+ action = irq_desc[i].action;
+ if (!action)
+ goto skip;
+ seq_printf(p, "%3d: ",i);
+#ifndef CONFIG_SMP
+ seq_printf(p, "%10u ", kstat_irqs(i));
+#else
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+#endif
+ seq_printf(p, " %8s", irq_desc[i].chip->name);
+ seq_printf(p, "-%-8s", irq_desc[i].name);
+
+ seq_printf(p, " %s", action->name);
+ for (action=action->next; action; action = action->next)
+ seq_printf(p, ", %s", action->name);
+ seq_putc(p, '\n');
+skip:
+ spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+ } else if (i == NR_IRQS) {
+ seq_printf(p, "NMI: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
+ seq_putc(p, '\n');
+ seq_printf(p, "LOC: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
+ seq_putc(p, '\n');
+ seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
+ }
+ return 0;
+}
+
+/*
+ * do_IRQ handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
+ */
+asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ /* high bit used in ret_from_ code */
+ unsigned vector = ~regs->orig_rax;
+ unsigned irq;
+
+ exit_idle();
+ irq_enter();
+ irq = __get_cpu_var(vector_irq)[vector];
+
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+ stack_overflow_check(regs);
+#endif
+
+ if (likely(irq < NR_IRQS))
+ generic_handle_irq(irq);
+ else {
+ if (!disable_apic)
+ ack_APIC_irq();
+
+ if (printk_ratelimit())
+ printk(KERN_EMERG "%s: %d.%d No irq handler for vector\n",
+ __func__, smp_processor_id(), vector);
+ }
+
+ irq_exit();
+
+ set_irq_regs(old_regs);
+ return 1;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+void fixup_irqs(cpumask_t map)
+{
+ unsigned int irq;
+ static int warned;
+
+ for (irq = 0; irq < NR_IRQS; irq++) {
+ cpumask_t mask;
+ int break_affinity = 0;
+ int set_affinity = 1;
+
+ if (irq == 2)
+ continue;
+
+ /* interrupt's are disabled at this point */
+ spin_lock(&irq_desc[irq].lock);
+
+ if (!irq_has_action(irq) ||
+ cpus_equal(irq_desc[irq].affinity, map)) {
+ spin_unlock(&irq_desc[irq].lock);
+ continue;
+ }
+
+ cpus_and(mask, irq_desc[irq].affinity, map);
+ if (cpus_empty(mask)) {
+ break_affinity = 1;
+ mask = map;
+ }
+
+ if (irq_desc[irq].chip->mask)
+ irq_desc[irq].chip->mask(irq);
+
+ if (irq_desc[irq].chip->set_affinity)
+ irq_desc[irq].chip->set_affinity(irq, mask);
+ else if (!(warned++))
+ set_affinity = 0;
+
+ if (irq_desc[irq].chip->unmask)
+ irq_desc[irq].chip->unmask(irq);
+
+ spin_unlock(&irq_desc[irq].lock);
+
+ if (break_affinity && set_affinity)
+ printk("Broke affinity for irq %i\n", irq);
+ else if (!set_affinity)
+ printk("Cannot set affinity for irq %i\n", irq);
+ }
+
+ /* That doesn't seem sufficient. Give it 1ms. */
+ local_irq_enable();
+ mdelay(1);
+ local_irq_disable();
+}
+#endif
+
+extern void call_softirq(void);
+
+asmlinkage void do_softirq(void)
+{
+ __u32 pending;
+ unsigned long flags;
+
+ if (in_interrupt())
+ return;
+
+ local_irq_save(flags);
+ pending = local_softirq_pending();
+ /* Switch to interrupt stack */
+ if (pending) {
+ call_softirq();
+ WARN_ON_ONCE(softirq_count());
+ }
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(do_softirq);