From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Goyal Subject: Re: [PATCH 18/21] blkcg: move blkio_group_conf->weight to cfq Date: Sun, 1 Apr 2012 17:09:56 -0400 Message-ID: <20120401210955.GE6116@redhat.com> References: <1332975091-10950-1-git-send-email-tj@kernel.org> <1332975091-10950-19-git-send-email-tj@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1332975091-10950-19-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Tejun Heo Cc: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, ctalbott-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, rni-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Fengguang Wu On Wed, Mar 28, 2012 at 03:51:28PM -0700, Tejun Heo wrote: > blkio_group_conf->weight is owned by cfq and has no reason to be > defined in blkcg core. Replace it with cfq_group->dev_weight and let > conf setting functions directly set it. If dev_weight is zero, the > cfqg doesn't have device specific weight configured. > > Also, rename BLKIO_WEIGHT_* constants to CFQ_WEIGHT_* and rename > blkio_cgroup->weight to blkio_cgroup->cfq_weight. We eventually want > per-policy storage in blkio_cgroup but just mark the ownership of the > field for now. Hi Tejun, blkio_cgroup->weight can be thought of in a more generic manner and that is sytem wide cgroup weight. And more than one policy should be allowed to make use of it. That's a differnt thing that currently only CFQ makes use of it. For example, Fengguang posted RFC patches to try to make use of blkcg->weight and differentiate between buffered write bandwidth. https://lkml.org/lkml/2012/3/28/275 Thanks Vivek