[PATCH] powerpc: re-enable dynticks

From: Paul Clarke
Date: Fri Feb 13 2015 - 14:39:37 EST


implement arch_irq_work_has_interrupt() for powerpc

Commit 9b01f5bf3 introduced a dependency on "IRQ work self-IPIs" for full dynamic ticks to be enabled, by expecting architectures to implement a suitable arch_irq_work_has_interrupt() routine.

Several arches have implemented this routine, including x86 (3010279f) and arm (09f6edd4), but powerpc was omitted.

This patch implements this routine for powerpc.

The symptom, at boot (on powerpc arch systems) with "nohz_full=<CPU list>" is displayed:
NO_HZ: Can't run full dynticks because arch doesn't support irq work self-IPIs

after this patch:
NO_HZ: Full dynticks CPUs: <CPU list>.

Tested against 3.19.

CC: Frederic Weisbecker <fweisbec@xxxxxxxxx>
CC: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Paul A. Clarke <pc@xxxxxxxxxx>

diff --git a/arch/powerpc/include/asm/irq_work.h b/arch/powerpc/include/asm/irq_work.h
new file mode 100644
index 0000000..18365ec
--- /dev/null
+++ b/arch/powerpc/include/asm/irq_work.h
@@ -0,0 +1,11 @@
+#ifndef _ASM_IRQ_WORK_H
+#define _ASM_IRQ_WORK_H
+
+#include <asm/processor.h>
+
+static inline bool arch_irq_work_has_interrupt(void)
+{
+ return 1;
+}
+
+#endif /* _ASM_IRQ_WORK_H */

--
Regards,
Paul Clarke, IBM

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/