From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 3 Apr 2011 11:57:29 +0200
Subject: genirq: Force interrupt thread on RT
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git
Git-commit: ff7814734fd8d39045530d6e5c3d51ee07e36982
Patch-mainline: Queued in subsystem maintainer repository
References: SLE Realtime Extension

Force threaded_irqs and optimize the code (force_irqthreads) in regard
to this.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
---
 include/linux/interrupt.h |    6 +++++-
 kernel/irq/manage.c       |    2 ++
 2 files changed, 7 insertions(+), 1 deletion(-)

--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -418,9 +418,13 @@ extern int irq_set_irqchip_state(unsigne
 				 bool state);
 
 #ifdef CONFIG_IRQ_FORCED_THREADING
+# ifndef CONFIG_PREEMPT_RT_BASE
 extern bool force_irqthreads;
+# else
+#  define force_irqthreads	(true)
+# endif
 #else
-#define force_irqthreads	(0)
+#define force_irqthreads	(false)
 #endif
 
 #ifndef __ARCH_SET_SOFTIRQ_PENDING
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -24,6 +24,7 @@
 #include "internals.h"
 
 #ifdef CONFIG_IRQ_FORCED_THREADING
+# ifndef CONFIG_PREEMPT_RT_BASE
 __read_mostly bool force_irqthreads;
 
 static int __init setup_forced_irqthreads(char *arg)
@@ -32,6 +33,7 @@ static int __init setup_forced_irqthread
 	return 0;
 }
 early_param("threadirqs", setup_forced_irqthreads);
+# endif
 #endif
 
 static void __synchronize_hardirq(struct irq_desc *desc)