[PATCH 05/23] cgroup: add subsystem pointer to cgroup_subsys_state
From: Tejun Heo <hidden>
Date: 2013-08-01 21:50:20
Also in:
lkml
Subsystem:
control group (cgroup), the rest · Maintainers:
Tejun Heo, Johannes Weiner, Michal Koutný, Linus Torvalds
Currently, given a cgroup_subsys_state, there's no way to find out which subsystem the css is for, which we'll need to convert the cgroup controller API to primarily use @css instead of @cgroup. This patch adds cgroup_subsys_state->ss which points to the subsystem the @css belongs to. While at it, remove the comment about accessing @css->cgroup to determine the hierarchy. cgroup core will provide API to traverse hierarchy of css'es and we don't want subsystems to directly walk cgroup hierarchies anymore. Signed-off-by: Tejun Heo <redacted> --- include/linux/cgroup.h | 9 ++++----- kernel/cgroup.c | 1 + 2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 1938292..9c2f9d7 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h@@ -66,13 +66,12 @@ enum cgroup_subsys_id { /* Per-subsystem/per-cgroup state maintained by the system. */ struct cgroup_subsys_state { - /* - * The cgroup that this subsystem is attached to. Useful - * for subsystems that want to know about the cgroup - * hierarchy structure - */ + /* the cgroup that this css is attached to */ struct cgroup *cgroup; + /* the cgroup subsystem that this css is attached to */ + struct cgroup_subsys *ss; + /* reference count - access via css_[try]get() and css_put() */ struct percpu_ref refcnt;
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 9d5af91..fad5498 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c@@ -4179,6 +4179,7 @@ static void init_cgroup_css(struct cgroup_subsys_state *css, struct cgroup *cgrp) { css->cgroup = cgrp; + css->ss = ss; css->flags = 0; css->id = NULL; if (cgrp == cgroup_dummy_top)
--
1.8.3.1