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Date:	Mon, 20 Oct 2014 18:25:43 +0200
From:	Daniel Lezcano <daniel.lezcano@...aro.org>
To:	rjw@...ysocki.net
Cc:	peterz@...radead.org, nicolas.pitre@...aro.org,
	linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
	linaro-kernel@...ts.linaro.org
Subject: [PATCH 5/5] cpuidle: menu: Move the update function before its declaration

In order to prevent a pointless forward declaration, just move the function
at the beginning of the file.

This patch does not change the behavior of the governor, it is just code
reordering.

Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
---
 drivers/cpuidle/governors/menu.c | 149 +++++++++++++++++++--------------------
 1 file changed, 74 insertions(+), 75 deletions(-)

diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 6ae8390..0ac76b1 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -184,7 +184,6 @@ static inline int performance_multiplier(unsigned long nr_iowaiters, unsigned lo
 
 static DEFINE_PER_CPU(struct menu_device, menu_devices);
 
-static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev);
 
 /* This implements DIV_ROUND_CLOSEST but avoids 64 bit division */
 static u64 div_round64(u64 dividend, u32 divisor)
@@ -192,6 +191,80 @@ static u64 div_round64(u64 dividend, u32 divisor)
 	return div_u64(dividend + (divisor / 2), divisor);
 }
 
+/**
+ * menu_update - attempts to guess what happened after entry
+ * @drv: cpuidle driver containing state data
+ * @dev: the CPU
+ */
+static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
+{
+	struct menu_device *data = &__get_cpu_var(menu_devices);
+	int last_idx = data->last_state_idx;
+	struct cpuidle_state *target = &drv->states[last_idx];
+	unsigned int measured_us;
+	unsigned int new_factor;
+
+	/*
+	 * Try to figure out how much time passed between entry to low
+	 * power state and occurrence of the wakeup event.
+	 *
+	 * If the entered idle state didn't support residency measurements,
+	 * we are basically lost in the dark how much time passed.
+	 * As a compromise, assume we slept for the whole expected time.
+	 *
+	 * Any measured amount of time will include the exit latency.
+	 * Since we are interested in when the wakeup begun, not when it
+	 * was completed, we must subtract the exit latency. However, if
+	 * the measured amount of time is less than the exit latency,
+	 * assume the state was never reached and the exit latency is 0.
+	 */
+	if (unlikely(!(target->flags & CPUIDLE_FLAG_TIME_VALID))) {
+		/* Use timer value as is */
+		measured_us = data->next_timer_us;
+
+	} else {
+		/* Use measured value */
+		measured_us = cpuidle_get_last_residency(dev);
+
+		/* Deduct exit latency */
+		if (measured_us > target->exit_latency)
+			measured_us -= target->exit_latency;
+
+		/* Make sure our coefficients do not exceed unity */
+		if (measured_us > data->next_timer_us)
+			measured_us = data->next_timer_us;
+	}
+
+	/* Update our correction ratio */
+	new_factor = data->correction_factor[data->bucket];
+	new_factor -= new_factor / DECAY;
+
+	if (data->next_timer_us > 0 && measured_us < MAX_INTERESTING)
+		new_factor += RESOLUTION * measured_us / data->next_timer_us;
+	else
+		/*
+		 * we were idle so long that we count it as a perfect
+		 * prediction
+		 */
+		new_factor += RESOLUTION;
+
+	/*
+	 * We don't want 0 as factor; we always want at least
+	 * a tiny bit of estimated time. Fortunately, due to rounding,
+	 * new_factor will stay nonzero regardless of measured_us values
+	 * and the compiler can eliminate this test as long as DECAY > 1.
+	 */
+	if (DECAY == 1 && unlikely(new_factor == 0))
+		new_factor = 1;
+
+	data->correction_factor[data->bucket] = new_factor;
+
+	/* update the repeating-pattern data */
+	data->intervals[data->interval_ptr++] = measured_us;
+	if (data->interval_ptr >= INTERVALS)
+		data->interval_ptr = 0;
+}
+
 /*
  * Try detecting repeating patterns by keeping track of the last 8
  * intervals, and checking if the standard deviation of that set
@@ -378,80 +451,6 @@ static void menu_reflect(struct cpuidle_device *dev, int index)
 }
 
 /**
- * menu_update - attempts to guess what happened after entry
- * @drv: cpuidle driver containing state data
- * @dev: the CPU
- */
-static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
-{
-	struct menu_device *data = &__get_cpu_var(menu_devices);
-	int last_idx = data->last_state_idx;
-	struct cpuidle_state *target = &drv->states[last_idx];
-	unsigned int measured_us;
-	unsigned int new_factor;
-
-	/*
-	 * Try to figure out how much time passed between entry to low
-	 * power state and occurrence of the wakeup event.
-	 *
-	 * If the entered idle state didn't support residency measurements,
-	 * we are basically lost in the dark how much time passed.
-	 * As a compromise, assume we slept for the whole expected time.
-	 *
-	 * Any measured amount of time will include the exit latency.
-	 * Since we are interested in when the wakeup begun, not when it
-	 * was completed, we must subtract the exit latency. However, if
-	 * the measured amount of time is less than the exit latency,
-	 * assume the state was never reached and the exit latency is 0.
-	 */
-	if (unlikely(!(target->flags & CPUIDLE_FLAG_TIME_VALID))) {
-		/* Use timer value as is */
-		measured_us = data->next_timer_us;
-
-	} else {
-		/* Use measured value */
-		measured_us = cpuidle_get_last_residency(dev);
-
-		/* Deduct exit latency */
-		if (measured_us > target->exit_latency)
-			measured_us -= target->exit_latency;
-
-		/* Make sure our coefficients do not exceed unity */
-		if (measured_us > data->next_timer_us)
-			measured_us = data->next_timer_us;
-	}
-
-	/* Update our correction ratio */
-	new_factor = data->correction_factor[data->bucket];
-	new_factor -= new_factor / DECAY;
-
-	if (data->next_timer_us > 0 && measured_us < MAX_INTERESTING)
-		new_factor += RESOLUTION * measured_us / data->next_timer_us;
-	else
-		/*
-		 * we were idle so long that we count it as a perfect
-		 * prediction
-		 */
-		new_factor += RESOLUTION;
-
-	/*
-	 * We don't want 0 as factor; we always want at least
-	 * a tiny bit of estimated time. Fortunately, due to rounding,
-	 * new_factor will stay nonzero regardless of measured_us values
-	 * and the compiler can eliminate this test as long as DECAY > 1.
-	 */
-	if (DECAY == 1 && unlikely(new_factor == 0))
-		new_factor = 1;
-
-	data->correction_factor[data->bucket] = new_factor;
-
-	/* update the repeating-pattern data */
-	data->intervals[data->interval_ptr++] = measured_us;
-	if (data->interval_ptr >= INTERVALS)
-		data->interval_ptr = 0;
-}
-
-/**
  * menu_enable_device - scans a CPU's states and does setup
  * @drv: cpuidle driver
  * @dev: the CPU
-- 
1.9.1

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