Re: [PATCH 12/21] cpuidle: call cpuidle_get_driver() from after takingcpuidle_driver_lock

From: Daniel Lezcano
Date: Wed Sep 25 2013 - 18:04:46 EST


On 09/22/2013 03:21 AM, Viresh Kumar wrote:
> cpuidle_driver_lock is taken correctly at most of the places but at few places
> calls to cpuidle_get_driver() are done from outside of this lock.
>
> Fix them by calling cpuidle_get_driver() after taking cpuidle_driver_lock.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>

> ---
> drivers/cpuidle/driver.c | 3 ++-
> drivers/cpuidle/sysfs.c | 3 ++-
> 2 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
> index 6279e1c..7b2510a 100644
> --- a/drivers/cpuidle/driver.c
> +++ b/drivers/cpuidle/driver.c
> @@ -340,10 +340,11 @@ struct cpuidle_driver *cpuidle_driver_ref(void)
> */
> void cpuidle_driver_unref(void)
> {
> - struct cpuidle_driver *drv = cpuidle_get_driver();
> + struct cpuidle_driver *drv;
>
> spin_lock(&cpuidle_driver_lock);
>
> + drv = cpuidle_get_driver();
> if (drv && !WARN_ON(drv->refcnt <= 0))
> drv->refcnt--;
>
> diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
> index 8739cc0..a022393 100644
> --- a/drivers/cpuidle/sysfs.c
> +++ b/drivers/cpuidle/sysfs.c
> @@ -52,9 +52,10 @@ static ssize_t show_current_driver(struct device *dev,
> char *buf)
> {
> ssize_t ret;
> - struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
> + struct cpuidle_driver *cpuidle_driver;
>
> spin_lock(&cpuidle_driver_lock);
> + cpuidle_driver = cpuidle_get_driver();
> if (cpuidle_driver)
> ret = sprintf(buf, "%s\n", cpuidle_driver->name);
> else
>


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