[patch 26/34] powerpc: Use generic idle loop

Thomas Gleixner
2013-03-21T21:55:51Z

[-- Attachment #1: powerpc-use-generic-idle-loop.patch --]
[-- Type: text/plain, Size: 3120 bytes --]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
arch/powerpc/Kconfig | 1
arch/powerpc/kernel/idle.c | 78 ++++++++++++---------------------------------
arch/powerpc/kernel/smp.c | 2 -
3 files changed, 24 insertions(+), 57 deletions(-)

Index: linux-2.6/arch/powerpc/Kconfig
===================================================================
--- linux-2.6.orig/arch/powerpc/Kconfig
+++ linux-2.6/arch/powerpc/Kconfig
@@ -133,6 +133,7 @@ config PPC
select HAVE_ARCH_JUMP_LABEL
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select GENERIC_SMP_IDLE_THREAD
+ select GENERIC_IDLE_LOOP
select GENERIC_CMOS_UPDATE
select GENERIC_TIME_VSYSCALL_OLD
select GENERIC_CLOCKEVENTS
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
@@ -50,64 +50,30 @@ static int __init powersave_off(char *ar
}
__setup("powersave=off", powersave_off);

-/*
- * The body of the idle task.
- */
-void cpu_idle(void)
+void arch_cpu_idle(void)
{
- set_thread_flag(TIF_POLLING_NRFLAG);
- while (1) {
- tick_nohz_idle_enter();
- rcu_idle_enter();
-
- while (!need_resched() && !cpu_should_die()) {
- ppc64_runlatch_off();
-
- if (ppc_md.power_save) {
- clear_thread_flag(TIF_POLLING_NRFLAG);
- /*
- * smp_mb is so clearing of TIF_POLLING_NRFLAG
- * is ordered w.r.t. need_resched() test.
- */
- smp_mb();
- local_irq_disable();
-
- /* Don't trace irqs off for idle */
- stop_critical_timings();
-
- /* check again after disabling irqs */
- if (!need_resched() && !cpu_should_die())
- ppc_md.power_save();
-
- start_critical_timings();
-
- /* Some power_save functions return with
- * interrupts enabled, some don't.
- */
- if (irqs_disabled())
- local_irq_enable();
- set_thread_flag(TIF_POLLING_NRFLAG);
-
- } else {
- /*
- * Go into low thread priority and possibly
- * low power mode.
- */
- HMT_low();
- HMT_very_low();
- }
- }
-
- HMT_medium();
- ppc64_runlatch_on();
- rcu_idle_exit();
- tick_nohz_idle_exit();
- if (cpu_should_die()) {
- sched_preempt_enable_no_resched();
- cpu_die();
- }
- schedule_preempt_disabled();
+ ppc64_runlatch_off();
+
+ if (ppc_md.power_save) {
+ ppc_md.power_save();
+ /*
+ * Some power_save functions return with
+ * interrupts enabled, some don't.
+ */
+ if (irqs_disabled())
+ local_irq_enable();
+ } else {
+ local_irq_enable();
+ /*
+ * Go into low thread priority and possibly
+ * low power mode.
+ */
+ HMT_low();
+ HMT_very_low();
}
+
+ HMT_medium();
+ ppc64_runlatch_on();
}

int powersave_nap;
Index: linux-2.6/arch/powerpc/kernel/smp.c
===================================================================
--- linux-2.6.orig/arch/powerpc/kernel/smp.c
+++ linux-2.6/arch/powerpc/kernel/smp.c
@@ -669,7 +669,7 @@ __cpuinit void start_secondary(void *unu

local_irq_enable();

- cpu_idle();
+ cpu_startup_entry(CPUHP_ONLINE);

BUG();
}