On Fri, Jun 27, 2014 at 09:03:06PM -0400, Tejun Heo wrote: > Hello, guys. > > Currently, the blkio subsystem attributes all of writeback IOs to the > root. One of the issues is that there's no way to tell who originated > a writeback IO from block layer. Those IOs are usually issued > asynchronously from a task which didn't have anything to do with > actually generating the dirty pages. The memory subsystem, when > enabled, already keeps track of the ownership of each dirty page and > it's desirable for blkio to piggyback instead of adding its own > per-page tag. > > This can be achieved on the unified hierarchy without too much > difficulty. This patchset implements a dependency mechanism in the > cgroup such that a subsystem can depends on other subsystems. If > available, the depended-upon subsystems are enabled together > implicitly when the subsystem is turned on. Implicitly enabled > subsystems are invisible and the dependencies are transparent to > userland. > > This patchset implements the dependency mechanism in cgroup core and > make blkcg depend on memcg. This doesn't actually solve the writeback > problem yet but is an important step. > > This patchset contains the following six patches. > > 0001-cgroup-reorganize-cgroup_subtree_control_write.patch > 0002-cgroup-introduce-cgroup-subtree_control.patch > 0003-cgroup-make-interface-files-visible-iff-enabled-on-c.patch > 0004-cgroup-implement-cgroup_subsys-css_reset.patch > 0005-cgroup-implement-cgroup_subsys-depends_on.patch > 0006-blkcg-memcg-make-blkcg-depend-on-memcg-on-the-defaul.patch These look good to me. Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> We can update memcg's ->css_reset() as we re-populate the interface in the default hierarchy. -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
