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Diffstat (limited to 'kernel/irq/manage.c')
-rw-r--r--kernel/irq/manage.c101
1 files changed, 81 insertions, 20 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index eb6078ca60c7..3164ba7ce151 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -138,6 +138,22 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
return 0;
}
+int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ unsigned long flags;
+
+ if (!desc)
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ desc->affinity_hint = m;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
+
#ifndef CONFIG_AUTO_IRQ_AFFINITY
/*
* Generic version of the affinity autoselector.
@@ -382,6 +398,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
{
struct irq_desc *desc = irq_to_desc(irq);
struct irqaction *action;
+ unsigned long flags;
if (!desc)
return 0;
@@ -389,11 +406,14 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
if (desc->status & IRQ_NOREQUEST)
return 0;
+ raw_spin_lock_irqsave(&desc->lock, flags);
action = desc->action;
if (action)
if (irqflags & action->flags & IRQF_SHARED)
action = NULL;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
return !action;
}
@@ -483,8 +503,26 @@ static int irq_wait_for_interrupt(struct irqaction *action)
*/
static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
{
+again:
chip_bus_lock(irq, desc);
raw_spin_lock_irq(&desc->lock);
+
+ /*
+ * Implausible though it may be we need to protect us against
+ * the following scenario:
+ *
+ * The thread is faster done than the hard interrupt handler
+ * on the other CPU. If we unmask the irq line then the
+ * interrupt can come in again and masks the line, leaves due
+ * to IRQ_INPROGRESS and the irq line is masked forever.
+ */
+ if (unlikely(desc->status & IRQ_INPROGRESS)) {
+ raw_spin_unlock_irq(&desc->lock);
+ chip_bus_sync_unlock(irq, desc);
+ cpu_relax();
+ goto again;
+ }
+
if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
desc->status &= ~IRQ_MASKED;
desc->chip->unmask(irq);
@@ -884,6 +922,12 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
desc->chip->disable(irq);
}
+#ifdef CONFIG_SMP
+ /* make sure affinity_hint is cleaned up */
+ if (WARN_ON_ONCE(desc->affinity_hint))
+ desc->affinity_hint = NULL;
+#endif
+
raw_spin_unlock_irqrestore(&desc->lock, flags);
unregister_handler_proc(irq, action);
@@ -995,7 +1039,6 @@ EXPORT_SYMBOL(free_irq);
* Flags:
*
* IRQF_SHARED Interrupt is shared
- * IRQF_DISABLED Disable local interrupts while processing
* IRQF_SAMPLE_RANDOM The interrupt can be used for entropy
* IRQF_TRIGGER_* Specify active edge(s) or level
*
@@ -1009,25 +1052,6 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
int retval;
/*
- * handle_IRQ_event() always ignores IRQF_DISABLED except for
- * the _first_ irqaction (sigh). That can cause oopsing, but
- * the behavior is classified as "will not fix" so we need to
- * start nudging drivers away from using that idiom.
- */
- if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
- (IRQF_SHARED|IRQF_DISABLED)) {
- pr_warning(
- "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
- irq, devname);
- }
-
-#ifdef CONFIG_LOCKDEP
- /*
- * Lockdep wants atomic interrupt handlers:
- */
- irqflags |= IRQF_DISABLED;
-#endif
- /*
* Sanity-check: shared interrupts must pass in a real dev-ID,
* otherwise we'll have trouble later trying to figure out
* which interrupt is which (messes up the interrupt freeing
@@ -1088,3 +1112,40 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
return retval;
}
EXPORT_SYMBOL(request_threaded_irq);
+
+/**
+ * request_any_context_irq - allocate an interrupt line
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs.
+ * Threaded handler for threaded interrupts.
+ * @flags: Interrupt type flags
+ * @name: An ascii name for the claiming device
+ * @dev_id: A cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources and enables the
+ * interrupt line and IRQ handling. It selects either a
+ * hardirq or threaded handling method depending on the
+ * context.
+ *
+ * On failure, it returns a negative value. On success,
+ * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
+ */
+int request_any_context_irq(unsigned int irq, irq_handler_t handler,
+ unsigned long flags, const char *name, void *dev_id)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ int ret;
+
+ if (!desc)
+ return -EINVAL;
+
+ if (desc->status & IRQ_NESTED_THREAD) {
+ ret = request_threaded_irq(irq, NULL, handler,
+ flags, name, dev_id);
+ return !ret ? IRQC_IS_NESTED : ret;
+ }
+
+ ret = request_irq(irq, handler, flags, name, dev_id);
+ return !ret ? IRQC_IS_HARDIRQ : ret;
+}
+EXPORT_SYMBOL_GPL(request_any_context_irq);