My main purpose of this patch is for memory controller.. This patch adds a handler "pre_destroy" to cgroup_subsys. It is called before cgroup_rmdir() checks all subsys's refcnt. I think this is useful for subsyses which have some extra refs even if there are no tasks in cgroup. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> include/linux/cgroup.h | 1 + kernel/cgroup.c | 7 +++++++ 2 files changed, 8 insertions(+) Index: devel-2.6.23-mm1/include/linux/cgroup.h =================================================================== --- devel-2.6.23-mm1.orig/include/linux/cgroup.h +++ devel-2.6.23-mm1/include/linux/cgroup.h @@ -233,6 +233,7 @@ int cgroup_is_descendant(const struct cg struct cgroup_subsys { struct cgroup_subsys_state *(*create)(struct cgroup_subsys *ss, struct cgroup *cont); + void (*pre_destroy)(struct cgroup_subsys *ss, struct cgroup *cont); void (*destroy)(struct cgroup_subsys *ss, struct cgroup *cont); int (*can_attach)(struct cgroup_subsys *ss, struct cgroup *cont, struct task_struct *tsk); Index: devel-2.6.23-mm1/kernel/cgroup.c =================================================================== --- devel-2.6.23-mm1.orig/kernel/cgroup.c +++ devel-2.6.23-mm1/kernel/cgroup.c @@ -2158,6 +2158,13 @@ static int cgroup_rmdir(struct inode *un parent = cont->parent; root = cont->root; sb = root->sb; + /* + * Notify subsyses that rmdir() request comes. + */ + for_each_subsys(root, ss) { + if ((cont->subsys[ss->subsys_id]) && ss->pre_destroy) + ss->pre_destroy(ss, cont); + } if (cgroup_has_css_refs(cont)) { mutex_unlock(&cgroup_mutex); _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers