android_kernel_xiaomi_sm8350/arch/alpha/kernel/irq.c
Ivan Kokshaysky eff2c2f6f5 [PATCH] alpha: fix IRQ handling lockup
Fix a lockup which was introduced during the conversion to the generic IRQ
framework.

Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-09 19:47:37 -08:00

164 lines
3.9 KiB
C

/*
* linux/arch/alpha/kernel/irq.c
*
* Copyright (C) 1995 Linus Torvalds
*
* This file contains the code used by various IRQ handling routines:
* asking for different IRQ's should be done through these routines
* instead of just grabbing them. Thus setups with different IRQ numbers
* shouldn't result in any weird surprises, and installing new handlers
* should be easier.
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel_stat.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/profile.h>
#include <linux/bitops.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/uaccess.h>
volatile unsigned long irq_err_count;
void ack_bad_irq(unsigned int irq)
{
irq_err_count++;
printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq);
}
#ifdef CONFIG_SMP
static char irq_user_affinity[NR_IRQS];
int
select_smp_affinity(unsigned int irq)
{
static int last_cpu;
int cpu = last_cpu + 1;
if (!irq_desc[irq].handler->set_affinity || irq_user_affinity[irq])
return 1;
while (!cpu_possible(cpu))
cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);
last_cpu = cpu;
irq_affinity[irq] = cpumask_of_cpu(cpu);
irq_desc[irq].handler->set_affinity(irq, cpumask_of_cpu(cpu));
return 0;
}
#endif /* CONFIG_SMP */
int
show_interrupts(struct seq_file *p, void *v)
{
#ifdef CONFIG_SMP
int j;
#endif
int irq = *(loff_t *) v;
struct irqaction * action;
unsigned long flags;
#ifdef CONFIG_SMP
if (irq == 0) {
seq_puts(p, " ");
for_each_online_cpu(j)
seq_printf(p, "CPU%d ", j);
seq_putc(p, '\n');
}
#endif
if (irq < ACTUAL_NR_IRQS) {
spin_lock_irqsave(&irq_desc[irq].lock, flags);
action = irq_desc[irq].action;
if (!action)
goto unlock;
seq_printf(p, "%3d: ", irq);
#ifndef CONFIG_SMP
seq_printf(p, "%10u ", kstat_irqs(irq));
#else
for_each_online_cpu(j)
seq_printf(p, "%10u ", kstat_cpu(j).irqs[irq]);
#endif
seq_printf(p, " %14s", irq_desc[irq].handler->typename);
seq_printf(p, " %c%s",
(action->flags & SA_INTERRUPT)?'+':' ',
action->name);
for (action=action->next; action; action = action->next) {
seq_printf(p, ", %c%s",
(action->flags & SA_INTERRUPT)?'+':' ',
action->name);
}
seq_putc(p, '\n');
unlock:
spin_unlock_irqrestore(&irq_desc[irq].lock, flags);
} else if (irq == ACTUAL_NR_IRQS) {
#ifdef CONFIG_SMP
seq_puts(p, "IPI: ");
for_each_online_cpu(j)
seq_printf(p, "%10lu ", cpu_data[j].ipi_count);
seq_putc(p, '\n');
#endif
seq_printf(p, "ERR: %10lu\n", irq_err_count);
}
return 0;
}
/*
* handle_irq handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*/
#define MAX_ILLEGAL_IRQS 16
void
handle_irq(int irq, struct pt_regs * regs)
{
/*
* We ack quickly, we don't want the irq controller
* thinking we're snobs just because some other CPU has
* disabled global interrupts (we have already done the
* INT_ACK cycles, it's too late to try to pretend to the
* controller that we aren't taking the interrupt).
*
* 0 return value means that this irq is already being
* handled by some other CPU. (or is disabled)
*/
static unsigned int illegal_count=0;
if ((unsigned) irq > ACTUAL_NR_IRQS && illegal_count < MAX_ILLEGAL_IRQS ) {
irq_err_count++;
illegal_count++;
printk(KERN_CRIT "device_interrupt: invalid interrupt %d\n",
irq);
return;
}
irq_enter();
/*
* __do_IRQ() must be called with IPL_MAX. Note that we do not
* explicitly enable interrupts afterwards - some MILO PALcode
* (namely LX164 one) seems to have severe problems with RTI
* at IPL 0.
*/
local_irq_disable();
__do_IRQ(irq, regs);
irq_exit();
}