Hi Andrea, > Implementing bio-cgroup functionality as pure infrastructure framework > instead of a cgroup subsystem would remove all this oddity and > complexity. > > For example, the actual functionality that I need for the io-throttle > controller is just an interface to set and get the cgroup owner of a > page. I think it should be the same also for other potential users of > bio-cgroup. > > So, what about implementing the bio-cgroup functionality as cgroup "page > tracking" infrastructure and provide the following interfaces: > > /* > * Encode the cgrp->css.id in page_group->flags > */ > void set_cgroup_page_owner(struct page *page, struct cgroup *cgrp); > > /* > * Returns the cgroup owner of a page, decoding the cgroup id from > * page_cgroup->flags. > */ > struct cgroup *get_cgroup_page_owner(struct page *page); > > This also wouldn't increase the size of page_cgroup because we can > encode the cgroup id in the unused bits of page_cgroup->flags, as > originally suggested by Kame. > > And I think it could be used also by dm-ioband, even if it's not a > cgroup-based subsystem... but I may be wrong. Ryo what's your opinion? I looked your page_cgroup patch in io-throttle v14, It can also be used by dm-ioband. But I'd like to eliminate lock_page_cgroup() to minimize overhead. I'll rearrange the bio-cgroup patch according to the functions. Thanks, Ryo Tsuruta _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
