[RFC V2 1/3] cpuidle: Remove pm_idle pointer for x86

[Trinabh Gupta <trinabh@linux.vnet.ibm.com>]

This patch reomves pm_idle function pointer and directly calls
cpuidle_idle_call from the idle loop on x86. CPUIdle has to be
built into the kernel.

Archs that still use pm_idle can continue to set
pm_idle=cpuidle_idle_call() and co-exist.  This will need #ifdefs
in cpuidle.c and has not been implemented yet in this RFC.

Signed-off-by: Trinabh Gupta <trinabh@linux.vnet.ibm.com>
---

 arch/x86/kernel/process_32.c |    4 +++-
 arch/x86/kernel/process_64.c |    4 +++-
 drivers/cpuidle/Kconfig      |    2 +-
 drivers/cpuidle/cpuidle.c    |    2 +-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 96586c3..d487ff8 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -76,6 +76,8 @@ static inline void play_dead(void)
 }
 #endif
 
+extern void cpuidle_idle_call(void);
+
 /*
  * The idle thread. There's no useful work to be
  * done, so just try to conserve power and have a
@@ -111,7 +113,7 @@ void cpu_idle(void)
 			local_irq_disable();
 			/* Don't trace irqs off for idle */
 			stop_critical_timings();
-			pm_idle();
+			cpuidle_idle_call();
 			start_critical_timings();
 
 			trace_power_end(smp_processor_id());
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index b3d7a3a..768cd23 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -101,6 +101,8 @@ static inline void play_dead(void)
 }
 #endif
 
+extern void cpuidle_idle_call(void);
+
 /*
  * The idle thread. There's no useful work to be
  * done, so just try to conserve power and have a
@@ -138,7 +140,7 @@ void cpu_idle(void)
 			enter_idle();
 			/* Don't trace irqs off for idle */
 			stop_critical_timings();
-			pm_idle();
+			cpuidle_idle_call();
 			start_critical_timings();
 
 			trace_power_end(smp_processor_id());
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index 7dbc4a8..57ad7bd 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -1,7 +1,7 @@
 
 config CPU_IDLE
 	bool "CPU idle PM support"
-	default ACPI
+	default y
 	help
 	  CPU idle is a generic framework for supporting software-controlled
 	  idle processor power management.  It includes modular cross-platform
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index a507108..9bf4640 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -47,7 +47,7 @@ static int __cpuidle_register_device(struct cpuidle_device *dev);
  *
  * NOTE: no locks or semaphores should be used here
  */
-static void cpuidle_idle_call(void)
+void cpuidle_idle_call(void)
 {
 	struct cpuidle_device *dev = __get_cpu_var(cpuidle_devices);
 	struct cpuidle_state *target_state;