s390/irq: Only define synchronize_irq() on SMP

commit 690cec8e70c211d1f5f6e520b21a68d0306173b6 upstream.

In uniprocessor configurations, synchronize_irq() is defined in
<linux/hardirq.h> as a macro, and this function definition fails to
compile.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 2032846aff9168d43d8d028faa2b82404c249517..1d95be95855f22d3da5be40c58e9444df7f2830d 100644 (file)
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -314,6 +314,7 @@ void measurement_alert_subclass_unregister(void)
 }
 EXPORT_SYMBOL(measurement_alert_subclass_unregister);
 
+#ifdef CONFIG_SMP
 void synchronize_irq(unsigned int irq)
 {
        /*
@@ -322,6 +323,7 @@ void synchronize_irq(unsigned int irq)
         */
 }
 EXPORT_SYMBOL_GPL(synchronize_irq);
+#endif
 
 #ifndef CONFIG_PCI