Subject: [PATCH RFC 1/3] PM / Domains: Allocate memory outside domain locks

From: [email-masked] (Krzysztof Kozlowski)
Date: Sun, 07 Jun 2015 17:35:10 +0900

W dniu 05.06.2015 o 07:29, Lina Iyer pisze:
> In order for domains to be powered on/off in irq locked context, the
> domain locks could either be a spinlock or a mutex, depending on the
> domain. In preparation for atomic support, allocate domain data outside
> the domain locks, so the allocation calls dont have to be context
> sensitive.
> 
> Cc: Ulf Hansson <[email-masked]>
> Cc: Rafael J. Wysocki <[email-masked]>
> Cc: Kevin Hilman <[email-masked]>
> Signed-off-by: Lina Iyer <[email-masked]>
> ---
>  drivers/base/power/domain.c | 25 ++++++++++++-------------
>  1 file changed, 12 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 3b3367b..dfd7595 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -1367,13 +1367,17 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
>  int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
>  			   struct generic_pm_domain *subdomain)
>  {
> -	struct gpd_link *link;
> +	struct gpd_link *link, *itr;
>  	int ret = 0;
>  
>  	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
>  	    || genpd == subdomain)
>  		return -EINVAL;
>  
> +	link = kzalloc(sizeof(*link), GFP_KERNEL);
> +	if (!link)
> +		return -ENOMEM;
> +
>  	mutex_lock(&genpd->lock);
>  	mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
>  
> @@ -1383,18 +1387,13 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
>  		goto out;
>  	}
>  
> -	list_for_each_entry(link, &genpd->master_links, master_node) {
> -		if (link->slave == subdomain && link->master == genpd) {
> +	list_for_each_entry(itr, &genpd->master_links, master_node) {
> +		if (itr->slave == subdomain && itr->master == genpd) {
>  			ret = -EINVAL;
>  			goto out;
>  		}
>  	}
>  
> -	link = kzalloc(sizeof(*link), GFP_KERNEL);
> -	if (!link) {
> -		ret = -ENOMEM;
> -		goto out;
> -	}
>  	link->master = genpd;
>  	list_add_tail(&link->master_node, &genpd->master_links);
>  	link->slave = subdomain;
> @@ -1496,17 +1495,17 @@ int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
>  	if (IS_ERR_OR_NULL(genpd) || state < 0)
>  		return -EINVAL;
>  
> +	cpuidle_data = kzalloc(sizeof(*cpuidle_data), GFP_KERNEL);
> +	if (!cpuidle_data)
> +		return -ENOMEM;
> +
>  	mutex_lock(&genpd->lock);
>  
>  	if (genpd->cpuidle_data) {
>  		ret = -EEXIST;
>  		goto out;

I think you must update the error paths. In this case the kfree() is
missing.

Best regards,
Krzysztof

>  	}
> -	cpuidle_data = kzalloc(sizeof(*cpuidle_data), GFP_KERNEL);
> -	if (!cpuidle_data) {
> -		ret = -ENOMEM;
> -		goto out;
> -	}
> +
>  	cpuidle_drv = cpuidle_driver_ref();
>  	if (!cpuidle_drv) {
>  		ret = -ENODEV;
>