linux-kernel - [PATCH] cpudile: optimize cpuidle_enable

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Date:   Fri, 1 Sep 2017 20:37:26 +0530
From:   gaurav jindal <gauravjindal1104@...il.com>
To:     rjw@...ysocki.net, daniel.lezcano@...aro.org
Cc:     linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] cpudile: optimize cpuidle_enable_device error handling

do not fetch per cpu drv id cpuidle_curr_governor is NULL.
if cpuidle_enable_device is NULL return -EIO. it prevents
the addtional per cpu processing

Signed-off-by: Gaurav Jindal<gauravjindal1104@...il.com>

---

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 1519716..6464e09 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -367,9 +367,12 @@ int cpuidle_enable_device(struct cpuidle_device *dev)
 	if (dev->enabled)
 		return 0;

+	if (!cpuidle_curr_governor)
+		return -EIO;
+
 	drv = cpuidle_get_cpu_driver(dev);

-	if (!drv || !cpuidle_curr_governor)
+	if (!drv)
 		return -EIO;

 	if (!dev->registered)