Re: [PATCH 09/20] blkio: Porpogate blkio cgroup weight or ioprio class updation to cfq groups

[Gui Jianfeng <guijianfeng@cn.fujitsu.com>]

Vivek Goyal wrote:
> o If a user decides the change the weight or ioprio class of a cgroup, this
>   information needs to be passed on to io controlling policy module also so
>   that new information can take effect.
> 
> Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
> ---
>  block/blk-cgroup.c  |   16 ++++++++++++++++
>  block/cfq-iosched.c |   18 ++++++++++++++++++
>  2 files changed, 34 insertions(+), 0 deletions(-)
> 
> diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
> index 7bde5c4..0d52a2c 100644
> --- a/block/blk-cgroup.c
> +++ b/block/blk-cgroup.c
> @@ -13,6 +13,10 @@
>  #include <linux/ioprio.h>
>  #include "blk-cgroup.h"
>  
> +extern void cfq_update_blkio_group_weight(struct blkio_group *, unsigned int);
> +extern void cfq_update_blkio_group_ioprio_class(struct blkio_group *,
> +		unsigned short);
> +
>  struct blkio_cgroup blkio_root_cgroup = {
>  	.weight = BLKIO_WEIGHT_DEFAULT,
>  	.ioprio_class = IOPRIO_CLASS_BE,
> @@ -75,12 +79,18 @@ static int
>  blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
>  {
>  	struct blkio_cgroup *blkcg;
> +	struct blkio_group *blkg;
> +	struct hlist_node *n;
>  
>  	if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX)
>  		return -EINVAL;
>  
>  	blkcg = cgroup_to_blkio_cgroup(cgroup);
> +	spin_lock_irq(&blkcg->lock);
>  	blkcg->weight = (unsigned int)val;
> +	hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node)
> +		cfq_update_blkio_group_weight(blkg, blkcg->weight);
> +	spin_unlock_irq(&blkcg->lock);
>  	return 0;
>  }
>  
> @@ -88,12 +98,18 @@ static int blkiocg_ioprio_class_write(struct cgroup *cgroup,
>  					struct cftype *cftype, u64 val)
>  {
>  	struct blkio_cgroup *blkcg;
> +	struct blkio_group *blkg;
> +	struct hlist_node *n;
>  
>  	if (val < IOPRIO_CLASS_RT || val > IOPRIO_CLASS_IDLE)
>  		return -EINVAL;
>  
>  	blkcg = cgroup_to_blkio_cgroup(cgroup);
> +	spin_lock_irq(&blkcg->lock);
>  	blkcg->ioprio_class = (unsigned int)val;
> +	hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node)
> +		cfq_update_blkio_group_weight(blkg, blkcg->weight);

  Here should be cfq_update_blkio_group_ioprio_class()

Thanks 
Gui