Messages in this thread | | | Date | Fri, 17 Apr 2009 12:41:35 +0200 | From | Andrea Righi <> | Subject | Re: [PATCH 1/9] io-throttle documentation |
| |
On Fri, Apr 17, 2009 at 12:25:40PM +0200, Andrea Righi wrote: > 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
sorry, I meant css_id(struct cgroup_subsys_state *css) here.
> */ > 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);
Or better, even more generic:
/* * Encode id in page_group->flags. */ void set_page_id(struct page *page, unsigned short id);
/* * Returns the id of a page, decoding it from page_cgroup->flags. */ unsigned short get_page_id(struct page *page);
Then we can use css_id() for cgroups, or any kind of ID for other potential users (dm-ioband, etc.).
-Andrea
> > 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?
| |