mn10300: Use generic idle loop

default_idle() boils down to safe_halt() and the other option is idle
polling. Use the core functionality.

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: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20130321215234.822656036@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig
index 428da175d0734abab132fbbbad57154b05530b1d..ae7158b69c9cc7d4f432858cf13f0ec1cbc10a98 100644 (file)
--- a/arch/mn10300/Kconfig
+++ b/arch/mn10300/Kconfig
@@ -13,6 +13,7 @@ config MN10300
        select MODULES_USE_ELF_RELA
        select OLD_SIGSUSPEND3
        select OLD_SIGACTION
+       select GENERIC_IDLE_LOOP
 
 config AM33_2
        def_bool n

diff --git a/arch/mn10300/kernel/process.c b/arch/mn10300/kernel/process.c
index 84f4e97e30745ad4d8e9b5d9e032dae5b775542b..2da39fb8b3b211351b7a4b402ebf7c4796d035d8 100644 (file)
--- a/arch/mn10300/kernel/process.c
+++ b/arch/mn10300/kernel/process.c
@@ -50,77 +50,19 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
 void (*pm_power_off)(void);
 EXPORT_SYMBOL(pm_power_off);
 
-#if !defined(CONFIG_SMP) || defined(CONFIG_HOTPLUG_CPU)
-/*
- * we use this if we don't have any better idle routine
- */
-static void default_idle(void)
-{
-       local_irq_disable();
-       if (!need_resched())
-               safe_halt();
-       else
-               local_irq_enable();
-}
-
-#else /* !CONFIG_SMP || CONFIG_HOTPLUG_CPU  */
 /*
  * On SMP it's slightly faster (but much more power-consuming!)
  * to poll the ->work.need_resched flag instead of waiting for the
  * cross-CPU IPI to arrive. Use this option with caution.
+ *
+ * tglx: No idea why this depends on HOTPLUG_CPU !?!
  */
-static inline void poll_idle(void)
-{
-       int oldval;
-
-       local_irq_enable();
-
-       /*
-        * Deal with another CPU just having chosen a thread to
-        * run here:
-        */
-       oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
-
-       if (!oldval) {
-               set_thread_flag(TIF_POLLING_NRFLAG);
-               while (!need_resched())
-                       cpu_relax();
-               clear_thread_flag(TIF_POLLING_NRFLAG);
-       } else {
-               set_need_resched();
-       }
-}
-#endif /* !CONFIG_SMP || CONFIG_HOTPLUG_CPU */
-
-/*
- * the idle thread
- * - there's no useful work to be done, so just try to conserve power and have
- *   a low exit latency (ie sit in a loop waiting for somebody to say that
- *   they'd like to reschedule)
- */
-void cpu_idle(void)
+#if !defined(CONFIG_SMP) || defined(CONFIG_HOTPLUG_CPU)
+void arch_cpu_idle(void)
 {
-       /* endless idle loop with no priority at all */
-       for (;;) {
-               rcu_idle_enter();
-               while (!need_resched()) {
-                       void (*idle)(void);
-
-                       smp_rmb();
-                       if (!idle) {
-#if defined(CONFIG_SMP) && !defined(CONFIG_HOTPLUG_CPU)
-                               idle = poll_idle;
-#else  /* CONFIG_SMP && !CONFIG_HOTPLUG_CPU */
-                               idle = default_idle;
-#endif /* CONFIG_SMP && !CONFIG_HOTPLUG_CPU */
-                       }
-                       idle();
-               }
-               rcu_idle_exit();
-
-               schedule_preempt_disabled();
-       }
+       safe_halt();
 }
+#endif
 
 void release_segments(struct mm_struct *mm)
 {

diff --git a/arch/mn10300/kernel/smp.c b/arch/mn10300/kernel/smp.c
index eaef5ad8e0ec061b090055c9da0963dfe67b274e..a17f9c9c14c9f3b7115d41f4ad765ee70de3ba2a 100644 (file)
--- a/arch/mn10300/kernel/smp.c
+++ b/arch/mn10300/kernel/smp.c
@@ -675,7 +675,7 @@ int __init start_secondary(void *unused)
 #ifdef CONFIG_GENERIC_CLOCKEVENTS
        init_clockevents();
 #endif
-       cpu_idle();
+       cpu_startup_entry(CPUHP_ONLINE);
        return 0;
 }