* 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 try_one_irq(int irq, struct irq_desc *desc)
+{
+ struct irqaction *action;
+ int ok = 0, work = 0;
+
+ raw_spin_lock(&desc->lock);
+ /* 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 & 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 (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;
+ }
+ 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) {
+ /*
+ * Perform real IRQ processing for the IRQ we deferred
+ */
+ 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
*/
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;
printk(KERN_ERR "irq event %d: bogus return value %x\n",
irq, action_ret);
} else {
- printk(KERN_ERR "irq %d: nobody cared!\n", irq);
+ printk(KERN_ERR "irq %d: nobody cared (try booting with "
+ "the \"irqpoll\" option)\n", irq);
}
dump_stack();
printk(KERN_ERR "handlers:\n");
+
action = desc->action;
while (action) {
printk(KERN_ERR "[<%p>]", action->handler);
}
}
-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)
+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 (action_ret != IRQ_HANDLED) {
- desc->irqs_unhandled++;
- if (action_ret != IRQ_NONE)
+ if (unlikely(action_ret != IRQ_HANDLED)) {
+ /*
+ * 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(try_misrouted_irq(irq, desc, action_ret))) {
+ int ok = misrouted_irq(irq);
+ if (action_ret == IRQ_NONE)
+ desc->irqs_unhandled -= ok;
+ }
+
desc->irq_count++;
- if (desc->irq_count < 100000)
+ if (likely(desc->irq_count < 100000))
return;
desc->irq_count = 0;
- if (desc->irqs_unhandled > 99900) {
+ if (unlikely(desc->irqs_unhandled > 99900)) {
/*
* The interrupt is stuck
*/
* Now kill the IRQ
*/
printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
- desc->status |= IRQ_DISABLED;
- desc->handler->disable(irq);
+ 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;
+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)
+{
+ irqfixup = 2;
+ printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
+ "enabled\n");
+ printk(KERN_WARNING "This may significantly impact system "
+ "performance\n");
+ return 1;
+}
+__setup("irqpoll", irqpoll_setup);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff