Re: [PATCH blktests 1/2] blktests: split out cgroup2 controller and file check

[Omar Sandoval <osandov@osandov.com>]

On Wed, Dec 12, 2018 at 06:09:58PM -0500, Dennis Zhou wrote:
> This is a prep patch for a new test that will race blkg association and
> request_queue cleanup. As blkg association is a underlying cgroup io
> controller feature, we need the ability to check if the controller is
> available.
> 
> Signed-off-by: Dennis Zhou <dennis@kernel.org>
> ---
>  common/cgroup | 18 +++++++++++++-----
>  1 file changed, 13 insertions(+), 5 deletions(-)
> 
> diff --git a/common/cgroup b/common/cgroup
> index d445093..3481458 100644
> --- a/common/cgroup
> +++ b/common/cgroup
> @@ -37,19 +37,27 @@ _have_cgroup2()
>  	return 0
>  }
>  
> -_have_cgroup2_controller_file()
> +_have_cgroup2_controller()
>  {
> -	_have_cgroup2 || return 1
> -
>  	local controller="$1"
> -	local file="$2"
> -	local dir
> +
> +	_have_cgroup2 || return 1
>  
>  	dir="$(_cgroup2_base_dir)"
> +
>  	if ! grep -q "$controller" "$dir/cgroup.controllers"; then
>  		SKIP_REASON="no support for $controller cgroup controller; if it is enabled, you may need to boot with cgroup_no_v1=$controller"
>  		return 1
>  	fi
> +}
> +
> +_have_cgroup2_controller_file()
> +{
> +	local controller="$1"
> +	local file="$2"
> +	local dir
> +
> +	_have_cgroup_2_controller "$controller" || return 1

This should be _have_cgroup2_controller. I'll fix it when I apply it.

>  
>  	mkdir "$dir/blktests"
>  	echo "+$controller" > "$dir/cgroup.subtree_control"
> -- 
> 2.17.1
>