linux-kernel - [PATCH 2/5] cpuidle/idle: Move the cpuidle_idle

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Message-Id: <1392131491-5265-2-git-send-email-daniel.lezcano@linaro.org>
Date:	Tue, 11 Feb 2014 16:11:28 +0100
From:	Daniel Lezcano <daniel.lezcano@...aro.org>
To:	mingo@...nel.org, peterz@...radead.org, tglx@...utronix.de,
	rjw@...ysocki.net
Cc:	nicolas.pitre@...aro.org, preeti@...ux.vnet.ibm.com,
	linux-kernel@...r.kernel.org
Subject: [PATCH 2/5] cpuidle/idle: Move the cpuidle_idle_call function to idle.c

The cpuidle_idle_call does nothing more than calling the three individuals
function and is no longer used by any arch specific code but only in the
cpuidle framework code.

We can move this function into the idle task code to ensure better
proximity to the scheduler code.

Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@...aro.org>
---
 drivers/cpuidle/cpuidle.c |   37 -------------------------------------
 include/linux/cpuidle.h   |    2 --
 kernel/sched/idle.c       |   44 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 39 deletions(-)

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 172ab6a..ae3078b 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -173,43 +173,6 @@ void cpuidle_reflect(struct cpuidle_device *dev, int index)
 }
 
 /**
- * cpuidle_idle_call - the main idle loop
- *
- * NOTE: no locks or semaphores should be used here
- * return non-zero on failure
- */
-int cpuidle_idle_call(void)
-{
-	struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
-	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
-	int next_state, entered_state;
-
-	/* ask the governor for the next state */
-	next_state = cpuidle_select(drv, dev);
-	if (next_state < 0)
-		return next_state;
-
-	if (need_resched()) {
-		dev->last_residency = 0;
-		/* give the governor an opportunity to reflect on the outcome */
-		cpuidle_reflect(dev, next_state);
-		local_irq_enable();
-		return 0;
-	}
-
-	trace_cpu_idle_rcuidle(next_state, dev->cpu);
-
-	entered_state = cpuidle_enter(drv, dev, next_state);
-
-	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
-
-	/* give the governor an opportunity to reflect on the outcome */
-	cpuidle_reflect(dev, entered_state);
-
-	return 0;
-}
-
-/**
  * cpuidle_install_idle_handler - installs the cpuidle idle loop handler
  */
 void cpuidle_install_idle_handler(void)
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index bf06f37..0befaff 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -126,7 +126,6 @@ extern int cpuidle_enter(struct cpuidle_driver *drv,
 			 struct cpuidle_device *dev, int index);
 extern void cpuidle_reflect(struct cpuidle_device *dev, int index);
 
-extern int cpuidle_idle_call(void);
 extern int cpuidle_register_driver(struct cpuidle_driver *drv);
 extern struct cpuidle_driver *cpuidle_get_driver(void);
 extern struct cpuidle_driver *cpuidle_driver_ref(void);
@@ -155,7 +154,6 @@ static inline int cpuidle_enter(struct cpuidle_driver *drv,
 				struct cpuidle_device *dev, int index)
 {return -ENODEV; }
 static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { }
-static inline int cpuidle_idle_call(void) { return -ENODEV; }
 static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
 {return -ENODEV; }
 static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; }
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 14ca434..6963822 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -63,6 +63,50 @@ void __weak arch_cpu_idle(void)
 	local_irq_enable();
 }
 
+#ifdef CONFIG_CPU_IDLE
+/**
+ * cpuidle_idle_call - the main idle function
+ *
+ * NOTE: no locks or semaphores should be used here
+ * return non-zero on failure
+ */
+static int cpuidle_idle_call(void)
+{
+	struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
+	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
+	int next_state, entered_state;
+
+	/* ask the governor for the next state */
+	next_state = cpuidle_select(drv, dev);
+	if (next_state < 0)
+		return next_state;
+
+	if (need_resched()) {
+		dev->last_residency = 0;
+		/* give the governor an opportunity to reflect on the outcome */
+		cpuidle_reflect(dev, next_state);
+		local_irq_enable();
+		return 0;
+	}
+
+	trace_cpu_idle_rcuidle(next_state, dev->cpu);
+
+	entered_state = cpuidle_enter(drv, dev, next_state);
+
+	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
+
+	/* give the governor an opportunity to reflect on the outcome */
+	cpuidle_reflect(dev, entered_state);
+
+	return 0;
+}
+#else
+static inline int cpuidle_idle_call(void)
+{
+	return -ENODEV;
+}
+#endif
+
 /*
  * Generic idle loop implementation
  */
-- 
1.7.9.5

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