linux/kernel/sched
Tejun Heo 6387698699 cgroup: add css_parent()
Currently, controllers have to explicitly follow the cgroup hierarchy
to find the parent of a given css.  cgroup is moving towards using
cgroup_subsys_state as the main controller interface construct, so
let's provide a way to climb the hierarchy using just csses.

This patch implements css_parent() which, given a css, returns its
parent.  The function is guarnateed to valid non-NULL parent css as
long as the target css is not at the top of the hierarchy.

freezer, cpuset, cpu, cpuacct, hugetlb, memory, net_cls and devices
are converted to use css_parent() instead of accessing cgroup->parent
directly.

* __parent_ca() is dropped from cpuacct and its usage is replaced with
  parent_ca().  The only difference between the two was NULL test on
  cgroup->parent which is now embedded in css_parent() making the
  distinction moot.  Note that eventually a css->parent field will be
  added to css and the NULL check in css_parent() will go away.

This patch shouldn't cause any behavior differences.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-08 20:11:23 -04:00
..
Makefile sched: Factor out load calculation code from sched/core.c --> sched/proc.c 2013-05-07 13:14:50 +02:00
auto_group.c sched/autogroup: Fix race with task_groups list 2013-05-28 09:40:22 +02:00
auto_group.h Revert "sched/autogroup: Fix crash on reboot when autogroup is disabled" 2012-12-11 10:23:45 +01:00
clock.c sched_clock: Prevent 64bit inatomicity on 32bit systems 2013-04-08 11:50:44 +02:00
core.c cgroup: add css_parent() 2013-08-08 20:11:23 -04:00
cpuacct.c cgroup: add css_parent() 2013-08-08 20:11:23 -04:00
cpuacct.h sched/cpuacct: Initialize root cpuacct earlier 2013-04-10 13:54:20 +02:00
cpupri.c sched/rt: Move rt specific bits into new header file 2013-02-07 20:51:08 +01:00
cpupri.h
cputime.c Linux 3.10 2013-07-01 11:18:53 +02:00
debug.c sched/debug: Remove CONFIG_FAIR_GROUP_SCHED mask 2013-06-28 13:17:17 +02:00
fair.c sched/fair: Fix typo describing flags in enqueue_entity 2013-06-27 10:18:25 +02:00
features.h mutex: Move mutex spinning code from sched/core.c back to mutex.c 2013-04-19 09:33:34 +02:00
idle_task.c sched: Keep at least 1 tick per second for active dynticks tasks 2013-05-04 08:32:02 +02:00
proc.c sched: Change get_rq_runnable_load() to static and inline 2013-06-27 10:07:44 +02:00
rt.c sched/rt: Simplify pull_rt_task() logic and remove .leaf_rt_rq_list 2013-06-19 12:58:40 +02:00
sched.h cgroup: s/cgroup_subsys_state/cgroup_css/ s/task_subsys_state/task_css/ 2013-08-08 20:11:22 -04:00
stats.c fix a leak in /proc/schedstats 2013-04-29 15:41:45 -04:00
stats.h Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-07-06 14:09:38 -07:00
stop_task.c sched: Use an accessor to read the rq clock 2013-05-28 09:40:27 +02:00