[PATCH] Add a function to handle interrupt affinity setting

Provide funtions to:
 - check, whether an interrupt can set the affinity
 - pin the interrupt to a given cpu

Necessary for the ability to setup clocksources more flexible (e.g.  use the
different HPET channels per CPU)

[akpm@osdl.org: alpha build fix]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 8930fb0ac9c7..29f715e71bdd 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -238,11 +238,21 @@ static inline void set_pending_irq(unsigned int irq, cpumask_t mask)
 
 #endif /* CONFIG_GENERIC_PENDING_IRQ */
 
+extern int irq_set_affinity(unsigned int irq, cpumask_t cpumask);
+extern int irq_can_set_affinity(unsigned int irq);
+
 #else /* CONFIG_SMP */
 
 #define move_native_irq(x)
 #define move_masked_irq(x)
 
+static inline int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
+{
+        return -EINVAL;
+}
+
+static inline int irq_can_set_affinity(unsigned int irq) { return 0; }
+
 #endif /* CONFIG_SMP */
 
 #ifdef CONFIG_IRQBALANCE