From 6803c006282768ec850760766a6e4eb1a6ff87df Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 23 Apr 2014 11:13:16 -0400 Subject: [PATCH] cgroup: add css_set->dfl_cgrp To implement the unified hierarchy behavior, we'll need to be able to determine the associated cgroup on the default hierarchy from css_set. Let's add css_set->dfl_cgrp so that it can be accessed conveniently and efficiently. Signed-off-by: Tejun Heo Acked-by: Li Zefan --- include/linux/cgroup.h | 3 +++ kernel/cgroup.c | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 18fcae3..c49d161 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -354,6 +354,9 @@ struct css_set { */ struct list_head cgrp_links; + /* the default cgroup associated with this css_set */ + struct cgroup *dfl_cgrp; + /* * Set of subsystem states, one for each subsystem. This array is * immutable after creation apart from the init_css_set during diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 2a4f88d..c66bfc8 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -651,6 +651,10 @@ static void link_css_set(struct list_head *tmp_links, struct css_set *cset, struct cgrp_cset_link *link; BUG_ON(list_empty(tmp_links)); + + if (cgroup_on_dfl(cgrp)) + cset->dfl_cgrp = cgrp; + link = list_first_entry(tmp_links, struct cgrp_cset_link, cset_link); link->cset = cset; link->cgrp = cgrp; -- 1.9.1