On Tue, Dec 20, 2016 at 11:12:17AM -0500, Tejun Heo wrote: > On cgroup v1, the pid listings in "cgroup.procs" and "tasks" are > sorted which adds a lot of complications and overhead. v2 doesn't > have such requirement and has been intentionally using a modified > sorting order so that the output doesn't look sorted to users. > > This patchset re-implements "cgroup.procs" reading for v2 which simply > keeps a css_task_iter open while the file is being read. Keeping the > iterator open makes it unnecessary to skip to the right position on > each read segment and associated errors - e.g. incorrectly skipping > over pids because earlier pids disappeared between the reads. > > Using persistent iterator across multiple read calls requires > ->release() callback to clean it up. kernfs operations > ->open/release() are added and piped through cftype.
Applied to cgroup/for-4.11. -- tejun
