linux-kernel - [PATCH V3 4/6] cpuidle: idle: menu: Don't reflect when a state selection failed

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Date:	Fri,  7 Nov 2014 15:31:25 +0100
From:	Daniel Lezcano <daniel.lezcano@...aro.org>
To:	rjw@...ysocki.net
Cc:	preeti@...ux.vnet.ibm.com, nicolas.pitre@...aro.org,
	linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
	peterz@...radead.org, linaro-kernel@...ts.linaro.org,
	patches@...aro.org, lenb@...nel.org
Subject: [PATCH V3 4/6] 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 chosen 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>
Acked-by: Nicolas Pitre <nico@...aro.org>
---
 drivers/cpuidle/governors/ladder.c | 3 +--
 drivers/cpuidle/governors/menu.c   | 3 +--
 kernel/sched/idle.c                | 3 ++-
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index 51c9ccd..86e4d49 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 = this_cpu_ptr(&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 91b3000..2e4a315 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -366,8 +366,7 @@ static void menu_reflect(struct cpuidle_device *dev, int index)
 {
 	struct menu_device *data = this_cpu_ptr(&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 0a7a1d1..0ae1cc8 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -173,7 +173,8 @@ 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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