Re: [PATCH] cgroup_rm_file: don't delete the uncreated files

[Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2012/12/6 11:09, Gao feng wrote:
> in cgroup_add_file,when creating files for cgroup,
> some of creation may be skipped. So we need to avoid
> deleting these uncreated files in cgroup_rm_file,
> otherwise the warning msg will be triggered.
> 
> "cgroup_addrm_files: failed to remove memory_pressure_enabled, err=-2"
> 
> Signed-off-by: Gao feng <gaofeng-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
> ---
>  kernel/cgroup.c |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 5cc3724..6928b3e 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -932,6 +932,12 @@ static int cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft)
>  	lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex);
>  	lockdep_assert_held(&cgroup_mutex);
>  
> +	/* does @cft->flags tell us this file isn't created on @cgrp? */
> +	if ((cft->flags & CFTYPE_NOT_ON_ROOT) && !cgrp->parent)
> +		return 0;
> +	if ((cft->flags & CFTYPE_ONLY_ON_ROOT) && cgrp->parent)
> +		return 0;
> +

We should move those checks to cgroup_addrm_files() to avoid code duplication.

>  	list_for_each_entry(cfe, &cgrp->files, node) {
>  		struct dentry *d = cfe->dentry;
>  
>