4 files changed, 81 insertions, 22 deletions

diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 131ca176b497..bfec453557b4 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -51,7 +51,7 @@ static void warn_no_thread(unsigned int irq, struct irqaction *action)
 	       "but no thread function available.", irq, action->name);
 }
 
-static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
+void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
 {
 	/*
 	 * In case the thread crashed and was killed we just pretend that
@@ -157,7 +157,7 @@ handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
 				break;
 			}
 
-			irq_wake_thread(desc, action);
+			__irq_wake_thread(desc, action);
 
 			/* Fall through to add to randomness */
 		case IRQ_HANDLED:
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 001fa5bab490..d61ac29e32d0 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -82,6 +82,7 @@ irqreturn_t handle_irq_event(struct irq_desc *desc);
 /* Resending of interrupts :*/
 void check_irq_resend(struct irq_desc *desc, unsigned int irq);
 bool irq_wait_for_poll(struct irq_desc *desc);
+void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
 
 #ifdef CONFIG_PROC_FS
 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 192a302d6cfd..8ab8e9390297 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -274,6 +274,7 @@ struct irq_desc *irq_to_desc(unsigned int irq)
 {
 	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 }
+EXPORT_SYMBOL(irq_to_desc);
 
 static void free_desc(unsigned int irq)
 {
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 481a13c43b17..54eb5c99351b 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -32,24 +32,10 @@ static int __init setup_forced_irqthreads(char *arg)
 early_param("threadirqs", setup_forced_irqthreads);
 #endif
 
-/**
- *	synchronize_irq - wait for pending IRQ handlers (on other CPUs)
- *	@irq: interrupt number to wait for
- *
- *	This function waits for any pending IRQ handlers for this interrupt
- *	to complete before returning. If you use this function while
- *	holding a resource the IRQ handler may need you will deadlock.
- *
- *	This function may be called - with care - from IRQ context.
- */
-void synchronize_irq(unsigned int irq)
+static void __synchronize_hardirq(struct irq_desc *desc)
 {
-	struct irq_desc *desc = irq_to_desc(irq);
 	bool inprogress;
 
-	if (!desc)
-		return;
-
 	do {
 		unsigned long flags;
 
@@ -67,12 +53,56 @@ void synchronize_irq(unsigned int irq)
 
 		/* Oops, that failed? */
 	} while (inprogress);
+}
 
-	/*
-	 * We made sure that no hardirq handler is running. Now verify
-	 * that no threaded handlers are active.
-	 */
-	wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active));
+/**
+ *	synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
+ *	@irq: interrupt number to wait for
+ *
+ *	This function waits for any pending hard IRQ handlers for this
+ *	interrupt to complete before returning. If you use this
+ *	function while holding a resource the IRQ handler may need you
+ *	will deadlock. It does not take associated threaded handlers
+ *	into account.
+ *
+ *	Do not use this for shutdown scenarios where you must be sure
+ *	that all parts (hardirq and threaded handler) have completed.
+ *
+ *	This function may be called - with care - from IRQ context.
+ */
+void synchronize_hardirq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	if (desc)
+		__synchronize_hardirq(desc);
+}
+EXPORT_SYMBOL(synchronize_hardirq);
+
+/**
+ *	synchronize_irq - wait for pending IRQ handlers (on other CPUs)
+ *	@irq: interrupt number to wait for
+ *
+ *	This function waits for any pending IRQ handlers for this interrupt
+ *	to complete before returning. If you use this function while
+ *	holding a resource the IRQ handler may need you will deadlock.
+ *
+ *	This function may be called - with care - from IRQ context.
+ */
+void synchronize_irq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	if (desc) {
+		__synchronize_hardirq(desc);
+		/*
+		 * We made sure that no hardirq handler is
+		 * running. Now verify that no threaded handlers are
+		 * active.
+		 */
+		wait_event(desc->wait_for_threads,
+			   !atomic_read(&desc->threads_active));
+	}
 }
 EXPORT_SYMBOL(synchronize_irq);
 
@@ -881,6 +911,33 @@ static int irq_thread(void *data)
 	return 0;
 }
 
+/**
+ *	irq_wake_thread - wake the irq thread for the action identified by dev_id
+ *	@irq:		Interrupt line
+ *	@dev_id:	Device identity for which the thread should be woken
+ *
+ */
+void irq_wake_thread(unsigned int irq, void *dev_id)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irqaction *action;
+	unsigned long flags;
+
+	if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
+		return;
+
+	raw_spin_lock_irqsave(&desc->lock, flags);
+	for (action = desc->action; action; action = action->next) {
+		if (action->dev_id == dev_id) {
+			if (action->thread)
+				__irq_wake_thread(desc, action);
+			break;
+		}
+	}
+	raw_spin_unlock_irqrestore(&desc->lock, flags);
+}
+EXPORT_SYMBOL_GPL(irq_wake_thread);
+
 static void irq_setup_forced_threading(struct irqaction *new)
 {
 	if (!force_irqthreads)