[Devel] [PATCH rh7 07/11] ub: cleanup cgroup attaching code

[Konstantin Khorenko]

Kirill, please review.

--
Best regards,

Konstantin Khorenko,
Virtuozzo Linux Kernel Team

On 05/20/2015 03:09 PM, Vladimir Davydov wrote:
> Signed-off-by: Vladimir Davydov <vdavydov at parallels.com>
> ---
>  kernel/bc/beancounter.c |   52 +++++++++++------------------------------------
>  1 file changed, 12 insertions(+), 40 deletions(-)
> 
> diff --git a/kernel/bc/beancounter.c b/kernel/bc/beancounter.c
> index b865f930bcb5..ee888d093583 100644
> --- a/kernel/bc/beancounter.c
> +++ b/kernel/bc/beancounter.c
> @@ -107,70 +107,42 @@ static void ub_cgroup_close(struct cgroup *root, struct cgroup *cg)
>  		cgroup_kernel_close(cg);
>  }
>  
> -static int ub_mem_cgroup_attach_task(struct user_beancounter *ub,
> -				     struct task_struct *tsk)
> +static int ub_cgroup_attach_task(struct cgroup *root,
> +		struct user_beancounter *ub, struct task_struct *tsk)
>  {
>  	struct cgroup *cg;
>  	int ret;
>  
> -	cg = ub_cgroup_open(mem_cgroup_root, ub);
> +	cg = ub_cgroup_open(root, ub);
>  	if (IS_ERR(cg))
>  		return PTR_ERR(cg);
>  	ret = cgroup_kernel_attach(cg, tsk);
> -	ub_cgroup_close(mem_cgroup_root, cg);
> -	return ret;
> -}
> -
> -static int ub_blkio_cgroup_attach_task(struct user_beancounter *ub,
> -				       struct task_struct *tsk)
> -{
> -	struct cgroup *cg;
> -	int ret;
> -
> -	cg = ub_cgroup_open(blkio_cgroup_root, ub);
> -	if (IS_ERR(cg))
> -		return PTR_ERR(cg);
> -	ret = cgroup_kernel_attach(cg, tsk);
> -	ub_cgroup_close(blkio_cgroup_root, cg);
> -	return ret;
> -}
> - 
> -static int ub_cgroup_attach_task(struct user_beancounter *ub,
> -				 struct task_struct *tsk)
> -{
> -	struct cgroup *cg;
> -	int ret;
> -
> -	cg = ub_cgroup_open(ub_cgroup_root, ub);
> -	if (IS_ERR(cg))
> -		return PTR_ERR(cg);
> -	ret = cgroup_kernel_attach(cg, tsk);
> -	ub_cgroup_close(ub_cgroup_root, cg);
> +	ub_cgroup_close(root, cg);
>  	return ret;
>  }
>  
>  int ub_attach_task(struct user_beancounter *ub, struct task_struct *tsk)
>  {
> -	int ret;
> +	int ret = 0;
>  	struct user_beancounter *old_ub = tsk->task_bc.exec_ub;
>  
> -	ret = ub_mem_cgroup_attach_task(ub, tsk);
> +	if (ub == old_ub)
> +		goto out;
> +	ret = ub_cgroup_attach_task(mem_cgroup_root, ub, tsk);
>  	if (ret)
>  		goto out;
> -	ret = ub_blkio_cgroup_attach_task(ub, tsk);
> +	ret = ub_cgroup_attach_task(blkio_cgroup_root, ub, tsk);
>  	if (ret)
>  		goto fail_blkio;
> -	ret = ub_cgroup_attach_task(ub, tsk);
> +	ret = ub_cgroup_attach_task(ub_cgroup_root, ub, tsk);
>  	if (ret)
>  		goto fail_ub;
>  out:
>  	return ret;
>  fail_ub:
> -	if (ub != old_ub)
> -		ub_blkio_cgroup_attach_task(old_ub, tsk);
> +	ub_cgroup_attach_task(blkio_cgroup_root, old_ub, tsk);
>  fail_blkio:
> -	if (ub != old_ub)
> -		ub_mem_cgroup_attach_task(old_ub, tsk);
> +	ub_cgroup_attach_task(mem_cgroup_root, old_ub, tsk);
>  	goto out;
>  }
>  
>