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/*
* 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;
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
*/
void ack_bad_irq(unsigned int irq)
{
printk(KERN_WARNING "unexpected IRQ trap at vector %02x\n", irq);
/*
* Currently unexpected vectors happen only on SMP and APIC.
* We _must_ ack these because every local APIC has only N
* irq slots per priority level, and a 'hanging, unacked' IRQ
* holds up an irq slot - in excessive cases (when multiple
* unexpected vectors occur) that might lock up the APIC
* completely.
* But don't ack when the APIC is disabled. -AK
*/
if (!disable_apic)
ack_APIC_irq();
}
#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->sp >= curbase && regs->sp <= curbase + THREAD_SIZE &&
regs->sp < curbase + sizeof(struct thread_info) + 128 &&
time_after(jiffies, warned + 60*HZ)) {
printk("do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n",
current->comm, curbase, regs->sp);
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) {
unsigned any_count = 0;
struct irq_desc *desc = __irq_to_desc(i);
if (!desc)
return 0;
spin_lock_irqsave(&desc->lock, flags);
#ifndef CONFIG_SMP
any_count = kstat_irqs(i);
#else
for_each_online_cpu(j)
any_count |= kstat_irqs_cpu(i, j);
#endif
action = desc->action;
if (!action && !any_count)
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_irqs_cpu(i, j));
#endif
seq_printf(p, " %8s", desc->chip->name);
seq_printf(p, "-%-8s", desc->name);
if (action) {
seq_printf(p, " %s", action->name);
while ((action = action->next) != NULL)
seq_printf(p, ", %s", action->name);
}
seq_putc(p, '\n');
skip:
spin_unlock_irqrestore(&desc->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_printf(p, " Non-maskable interrupts\n");
seq_printf(p, "LOC: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
seq_printf(p, " Local timer interrupts\n");
#ifdef CONFIG_SMP
seq_printf(p, "RES: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->irq_resched_count);
seq_printf(p, " Rescheduling interrupts\n");
seq_printf(p, "CAL: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->irq_call_count);
seq_printf(p, " Function call interrupts\n");
seq_printf(p, "TLB: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->irq_tlb_count);
seq_printf(p, " TLB shootdowns\n");
#endif
#ifdef CONFIG_X86_MCE
seq_printf(p, "TRM: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->irq_thermal_count);
seq_printf(p, " Thermal event interrupts\n");
seq_printf(p, "THR: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->irq_threshold_count);
seq_printf(p, " Threshold APIC interrupts\n");
#endif
seq_printf(p, "SPU: ");
for_each_online_cpu(j)
seq_printf(p, "%10u ", cpu_pda(j)->irq_spurious_count);
seq_printf(p, " Spurious interrupts\n");
seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
}
return 0;
}
/*
* /proc/stat helpers
*/
u64 arch_irq_stat_cpu(unsigned int cpu)
{
u64 sum = cpu_pda(cpu)->__nmi_count;
sum += cpu_pda(cpu)->apic_timer_irqs;
#ifdef CONFIG_SMP
sum += cpu_pda(cpu)->irq_resched_count;
sum += cpu_pda(cpu)->irq_call_count;
sum += cpu_pda(cpu)->irq_tlb_count;
#endif
#ifdef CONFIG_X86_MCE
sum += cpu_pda(cpu)->irq_thermal_count;
sum += cpu_pda(cpu)->irq_threshold_count;
#endif
sum += cpu_pda(cpu)->irq_spurious_count;
return sum;
}
u64 arch_irq_stat(void)
{
return atomic_read(&irq_err_count);
}
/*
* 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);
struct irq_desc *desc;
/* high bit used in ret_from_ code */
unsigned vector = ~regs->orig_ax;
unsigned irq;
exit_idle();
irq_enter();
irq = __get_cpu_var(vector_irq)[vector];
#ifdef CONFIG_DEBUG_STACKOVERFLOW
stack_overflow_check(regs);
#endif
desc = __irq_to_desc(irq);
if (likely(desc))
generic_handle_irq_desc(irq, desc);
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;
struct irq_desc *desc;
for_each_irq_desc(irq, desc) {
cpumask_t mask;
int break_affinity = 0;
int set_affinity = 1;
if (irq == 2)
continue;
/* interrupt's are disabled at this point */
spin_lock(&desc->lock);
if (!irq_has_action(irq) ||
cpus_equal(desc->affinity, map)) {
spin_unlock(&desc->lock);
continue;
}
cpus_and(mask, desc->affinity, map);
if (cpus_empty(mask)) {
break_affinity = 1;
mask = map;
}
if (desc->chip->mask)
desc->chip->mask(irq);
if (desc->chip->set_affinity)
desc->chip->set_affinity(irq, mask);
else if (!(warned++))
set_affinity = 0;
if (desc->chip->unmask)
desc->chip->unmask(irq);
spin_unlock(&desc->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);
}
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