[PATCH 2.6.21-rt2] PowerPC: enable HRT and dynticks support

From: Sergei Shtylyov
Date: Thu May 17 2007 - 13:45:27 EST


Enable HRT and dynamic ticks support for PowerPC.

Signed-off-by: Sergei Shtylyov <sshtylyov@xxxxxxxxxxxxx>

---
This patch has been reworked against the 2.6.21 clockevents framework.
It has only been tested on the Book E 32-bit CPU this time, so re-testing on
"classic" PowerPC CPUs is needed (there have been issues as of 2.6.18-rt7 but
those should now be fixed)...

arch/powerpc/Kconfig | 1 +
arch/powerpc/kernel/idle.c | 3 +++
2 files changed, 4 insertions(+)

Index: linux-2.6/arch/powerpc/Kconfig
===================================================================
--- linux-2.6.orig/arch/powerpc/Kconfig
+++ linux-2.6/arch/powerpc/Kconfig
@@ -770,6 +770,7 @@ config GENERIC_CLOCKEVENTS
NOTE: This is not compatible with the deterministic time accounting
option on PPC64.

+source kernel/time/Kconfig
source kernel/Kconfig.preempt

config RWSEM_GENERIC_SPINLOCK
Index: linux-2.6/arch/powerpc/kernel/idle.c
===================================================================
--- linux-2.6.orig/arch/powerpc/kernel/idle.c
+++ linux-2.6/arch/powerpc/kernel/idle.c
@@ -24,6 +24,7 @@
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/sysctl.h>
+#include <linux/tick.h>

#include <asm/system.h>
#include <asm/processor.h>
@@ -56,6 +57,7 @@ void cpu_idle(void)

set_thread_flag(TIF_POLLING_NRFLAG);
while (1) {
+ tick_nohz_stop_sched_tick();
while (!need_resched() && !need_resched_delayed() &&
!cpu_should_die()) {
ppc64_runlatch_off();
@@ -92,6 +94,7 @@ void cpu_idle(void)
ppc64_runlatch_on();
if (cpu_should_die())
cpu_die();
+ tick_nohz_restart_sched_tick();
__preempt_enable_no_resched();
schedule();
preempt_disable();

-
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/