On 2013/7/12 1:20, Tejun Heo wrote: >>From 705da98c48f39ebe565439353a5b35a0bab08b23 Mon Sep 17 00:00:00 2001 > From: Tejun Heo <tj@xxxxxxxxxx> > Date: Fri, 28 Jun 2013 17:07:30 -0700 > > Currently, creating and removing cgroup files in the root directory > are handled separately from the actual subsystem binding and unbinding > which happens in rebind_subsystems(). Also, rebind_subsystems() users > aren't handling file creation errors properly. Let's integrate > top_cgroup file handling into rebind_subsystems() so that it's simpler > to use and everyone handles file creation errors correctly. > > * On a successful return, rebind_subsystems() is guaranteed to have > created all files of the new subsystems and deleted the ones > belonging to the removed subsystems. After a failure, no file is > created or removed. > > * cgroup_remount() no longer needs to make explicit populate/clear > calls as it's all handled by rebind_subsystems(), and it gets proper > error handling automatically. > > * cgroup_mount() has been updated such that the root dentry and cgroup > are linked before rebind_subsystems(). Also, the init_cred dancing > and base file handling are moved right above rebind_subsystems() > call and proper error handling for the base files is added. While > at it, add a comment explaining what's going on with the cred thing. > > * cgroup_kill_sb() calls rebind_subsystems() to unbind all subsystems > which now implies removing all subsystem files which requires the > directory's i_mutex. Grab it. This means that files on the root > cgroup are removed earlier - they used to be deleted from generic > super_block cleanup from vfs. This doesn't lead to any functional > difference and it's cleaner to do the clean up explicitly for all > files. > > Combined with the previous changes, this makes all cgroup file > creation errors handled correctly. > > v2: Added comment on init_cred. > > v3: Li spotted that cgroup_mount() wasn't freeing tmp_links after base > file addition failure. Fix it by adding free_tmp_links error > handling label. > > Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Acked-by: Li Zefan <lizefan@xxxxxxxxxx> _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers
