* This file contains spurious interrupt handling.
*/
+#include <linux/jiffies.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
+#include <linux/moduleparam.h>
+#include <linux/timer.h>
static int irqfixup __read_mostly;
+#define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10)
+static void poll_spurious_irqs(unsigned long dummy);
+static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs, 0, 0);
+
/*
* Recovery handler for misrouted interrupts.
*/
-
-static int misrouted_irq(int irq, struct pt_regs *regs)
+static int try_one_irq(int irq, struct irq_desc *desc)
{
- int i;
- irq_desc_t *desc;
- int ok = 0;
- int work = 0; /* Did we do work for a real IRQ */
-
- for(i = 1; i < NR_IRQS; i++) {
- struct irqaction *action;
-
- if (i == irq) /* Already tried */
- continue;
- desc = &irq_desc[i];
- spin_lock(&desc->lock);
- action = desc->action;
- /* Already running on another processor */
- if (desc->status & IRQ_INPROGRESS) {
- /*
- * Already running: If it is shared get the other
- * CPU to go looking for our mystery interrupt too
- */
- if (desc->action && (desc->action->flags & SA_SHIRQ))
- desc->status |= IRQ_PENDING;
- spin_unlock(&desc->lock);
- continue;
- }
- /* Honour the normal IRQ locking */
- desc->status |= IRQ_INPROGRESS;
- spin_unlock(&desc->lock);
- while (action) {
- /* Only shared IRQ handlers are safe to call */
- if (action->flags & SA_SHIRQ) {
- if (action->handler(i, action->dev_id, regs) ==
- IRQ_HANDLED)
- ok = 1;
- }
- action = action->next;
- }
- local_irq_disable();
- /* Now clean up the flags */
- spin_lock(&desc->lock);
- action = desc->action;
+ struct irqaction *action;
+ int ok = 0, work = 0;
+ raw_spin_lock(&desc->lock);
+ /* Already running on another processor */
+ if (desc->status & IRQ_INPROGRESS) {
/*
- * While we were looking for a fixup someone queued a real
- * IRQ clashing with our walk
+ * Already running: If it is shared get the other
+ * CPU to go looking for our mystery interrupt too
*/
+ if (desc->action && (desc->action->flags & IRQF_SHARED))
+ desc->status |= IRQ_PENDING;
+ raw_spin_unlock(&desc->lock);
+ return ok;
+ }
+ /* Honour the normal IRQ locking */
+ desc->status |= IRQ_INPROGRESS;
+ action = desc->action;
+ raw_spin_unlock(&desc->lock);
- while ((desc->status & IRQ_PENDING) && action) {
- /*
- * Perform real IRQ processing for the IRQ we deferred
- */
- work = 1;
- spin_unlock(&desc->lock);
- handle_IRQ_event(i, regs, action);
- spin_lock(&desc->lock);
- desc->status &= ~IRQ_PENDING;
+ while (action) {
+ /* Only shared IRQ handlers are safe to call */
+ if (action->flags & IRQF_SHARED) {
+ if (action->handler(irq, action->dev_id) ==
+ IRQ_HANDLED)
+ ok = 1;
}
- desc->status &= ~IRQ_INPROGRESS;
+ action = action->next;
+ }
+ local_irq_disable();
+ /* Now clean up the flags */
+ raw_spin_lock(&desc->lock);
+ action = desc->action;
+
+ /*
+ * While we were looking for a fixup someone queued a real
+ * IRQ clashing with our walk:
+ */
+ while ((desc->status & IRQ_PENDING) && action) {
/*
- * If we did actual work for the real IRQ line we must let the
- * IRQ controller clean up too
+ * Perform real IRQ processing for the IRQ we deferred
*/
- if(work)
- desc->chip->end(i);
- spin_unlock(&desc->lock);
+ work = 1;
+ raw_spin_unlock(&desc->lock);
+ handle_IRQ_event(irq, action);
+ raw_spin_lock(&desc->lock);
+ desc->status &= ~IRQ_PENDING;
+ }
+ desc->status &= ~IRQ_INPROGRESS;
+ /*
+ * If we did actual work for the real IRQ line we must let the
+ * IRQ controller clean up too
+ */
+ if (work && desc->chip && desc->chip->end)
+ desc->chip->end(irq);
+ raw_spin_unlock(&desc->lock);
+
+ return ok;
+}
+
+static int misrouted_irq(int irq)
+{
+ struct irq_desc *desc;
+ int i, ok = 0;
+
+ for_each_irq_desc(i, desc) {
+ if (!i)
+ continue;
+
+ if (i == irq) /* Already tried */
+ continue;
+
+ if (try_one_irq(i, desc))
+ ok = 1;
}
/* So the caller can adjust the irq error counts */
return ok;
}
+static void poll_spurious_irqs(unsigned long dummy)
+{
+ struct irq_desc *desc;
+ int i;
+
+ for_each_irq_desc(i, desc) {
+ unsigned int status;
+
+ if (!i)
+ continue;
+
+ /* Racy but it doesn't matter */
+ status = desc->status;
+ barrier();
+ if (!(status & IRQ_SPURIOUS_DISABLED))
+ continue;
+
+ local_irq_disable();
+ try_one_irq(i, desc);
+ local_irq_enable();
+ }
+
+ mod_timer(&poll_spurious_irq_timer,
+ jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
+}
+
/*
* If 99,900 of the previous 100,000 interrupts have not been handled
* then assume that the IRQ is stuck in some manner. Drop a diagnostic
*/
static void
-__report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+__report_bad_irq(unsigned int irq, struct irq_desc *desc,
+ irqreturn_t action_ret)
{
struct irqaction *action;
}
dump_stack();
printk(KERN_ERR "handlers:\n");
+
action = desc->action;
while (action) {
printk(KERN_ERR "[<%p>]", action->handler);
}
}
-static void report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+static void
+report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret)
{
static int count = 100;
}
}
-void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret,
- struct pt_regs *regs)
+static inline int
+try_misrouted_irq(unsigned int irq, struct irq_desc *desc,
+ irqreturn_t action_ret)
+{
+ struct irqaction *action;
+
+ if (!irqfixup)
+ return 0;
+
+ /* We didn't actually handle the IRQ - see if it was misrouted? */
+ if (action_ret == IRQ_NONE)
+ return 1;
+
+ /*
+ * But for 'irqfixup == 2' we also do it for handled interrupts if
+ * they are marked as IRQF_IRQPOLL (or for irq zero, which is the
+ * traditional PC timer interrupt.. Legacy)
+ */
+ if (irqfixup < 2)
+ return 0;
+
+ if (!irq)
+ return 1;
+
+ /*
+ * Since we don't get the descriptor lock, "action" can
+ * change under us. We don't really care, but we don't
+ * want to follow a NULL pointer. So tell the compiler to
+ * just load it once by using a barrier.
+ */
+ action = desc->action;
+ barrier();
+ return action && (action->flags & IRQF_IRQPOLL);
+}
+
+void note_interrupt(unsigned int irq, struct irq_desc *desc,
+ irqreturn_t action_ret)
{
if (unlikely(action_ret != IRQ_HANDLED)) {
- desc->irqs_unhandled++;
+ /*
+ * If we are seeing only the odd spurious IRQ caused by
+ * bus asynchronicity then don't eventually trigger an error,
+ * otherwise the counter becomes a doomsday timer for otherwise
+ * working systems
+ */
+ if (time_after(jiffies, desc->last_unhandled + HZ/10))
+ desc->irqs_unhandled = 1;
+ else
+ desc->irqs_unhandled++;
+ desc->last_unhandled = jiffies;
if (unlikely(action_ret != IRQ_NONE))
report_bad_irq(irq, desc, action_ret);
}
- if (unlikely(irqfixup)) {
- /* Don't punish working computers */
- if ((irqfixup == 2 && irq == 0) || action_ret == IRQ_NONE) {
- int ok = misrouted_irq(irq, regs);
- if (action_ret == IRQ_NONE)
- desc->irqs_unhandled -= ok;
- }
+ if (unlikely(try_misrouted_irq(irq, desc, action_ret))) {
+ int ok = misrouted_irq(irq);
+ if (action_ret == IRQ_NONE)
+ desc->irqs_unhandled -= ok;
}
desc->irq_count++;
* Now kill the IRQ
*/
printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
- desc->status |= IRQ_DISABLED;
+ desc->status |= IRQ_DISABLED | IRQ_SPURIOUS_DISABLED;
+ desc->depth++;
desc->chip->disable(irq);
+
+ mod_timer(&poll_spurious_irq_timer,
+ jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
}
desc->irqs_unhandled = 0;
}
int noirqdebug __read_mostly;
-int __init noirqdebug_setup(char *str)
+int noirqdebug_setup(char *str)
{
noirqdebug = 1;
printk(KERN_INFO "IRQ lockup detection disabled\n");
+
return 1;
}
__setup("noirqdebug", noirqdebug_setup);
+module_param(noirqdebug, bool, 0644);
+MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
static int __init irqfixup_setup(char *str)
{
irqfixup = 1;
printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
printk(KERN_WARNING "This may impact system performance.\n");
+
return 1;
}
__setup("irqfixup", irqfixup_setup);
+module_param(irqfixup, int, 0644);
static int __init irqpoll_setup(char *str)
{