powerpc: Use generic idle loop

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Link: http://lkml.kernel.org/r/20130321215235.026838003@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index ea5bb04..19de32c 100644 (file)
--- a/arch/powerpc/Kconfig
+++ b/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

diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c
index ea78761..939ea7e 100644 (file)
--- a/arch/powerpc/kernel/idle.c
+++ b/arch/powerpc/kernel/idle.c
@@ -33,11 +33,6 @@
 #include <asm/runlatch.h>
 #include <asm/smp.h>
 
-#ifdef CONFIG_HOTPLUG_CPU
-#define cpu_should_die()       cpu_is_offline(smp_processor_id())
-#else
-#define cpu_should_die()       0
-#endif
 
 unsigned long cpuidle_disable = IDLE_NO_OVERRIDE;
 EXPORT_SYMBOL(cpuidle_disable);
@@ -50,64 +45,38 @@ static int __init powersave_off(char *arg)
 }
 __setup("powersave=off", powersave_off);
 
-/*
- * The body of the idle task.
- */
-void cpu_idle(void)
+#ifdef CONFIG_HOTPLUG_CPU
+void arch_cpu_idle_dead(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();
-                       }
-               }
+       sched_preempt_enable_no_resched();
+       cpu_die();
+}
+#endif
 
-               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();
+void arch_cpu_idle(void)
+{
+       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;

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 76bd9da..ee7ac5e 100644 (file)
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -669,7 +669,7 @@ __cpuinit void start_secondary(void *unused)
 
        local_irq_enable();
 
-       cpu_idle();
+       cpu_startup_entry(CPUHP_ONLINE);
 
        BUG();
 }