linux-kernel - [PATCH 3/5] cpuidle: idle: menu: Don't reflect when a state selection failed

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Date:	Mon, 20 Oct 2014 18:25:41 +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 3/5] cpuidle: idle: menu: Don't reflect when a state selection failed

In the current code, the check to reflect or not the outcoming state is done
against the idle state which has been choose and its value.

Instead of doing a check in each of the reflect functions, just don't call reflect
if something went wrong in the idle path.

Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
---
 drivers/cpuidle/governors/ladder.c | 3 +--
 drivers/cpuidle/governors/menu.c   | 4 +---
 kernel/sched/idle.c                | 3 ++-
 3 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index fb396d6..c0b36a8 100644
--- a/drivers/cpuidle/governors/ladder.c
+++ b/drivers/cpuidle/governors/ladder.c
@@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv,
 static void ladder_reflect(struct cpuidle_device *dev, int index)
 {
 	struct ladder_device *ldev = &__get_cpu_var(ladder_devices);
-	if (index > 0)
-		ldev->last_state_idx = index;
+	ldev->last_state_idx = index;
 }
 
 static struct cpuidle_governor ladder_governor = {
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index a17515f..3907301 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 static void menu_reflect(struct cpuidle_device *dev, int index)
 {
 	struct menu_device *data = &__get_cpu_var(menu_devices);
-	data->last_state_idx = index;
-	if (index >= 0)
-		data->needs_update = 1;
+	data->needs_update = 1;
 }
 
 /**
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index f439161..9ac7322 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -162,7 +162,8 @@ use_default:
 	/*
 	 * Give the governor an opportunity to reflect on the outcome
 	 */
-	cpuidle_reflect(dev, entered_state);
+	if (entered_state >= 0)
+		cpuidle_reflect(dev, entered_state);
 
 exit_idle:
 	__current_set_polling();
-- 
1.9.1

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