diff options
author | Tejun Heo <tj@kernel.org> | 2014-11-18 02:49:51 -0500 |
---|---|---|
committer | Tejun Heo <tj@kernel.org> | 2014-11-18 02:49:51 -0500 |
commit | 56c807ba4e91f0980567b6a69de239677879b17f (patch) | |
tree | 509bdb009fdd4cbc87c75b2138e07600afc357ac /kernel/cgroup.c | |
parent | 7d172cc89b8589e4173d0c73a1ddaae408f29c9d (diff) |
cgroup: add cgroup_subsys->css_e_css_changed()
Add a new cgroup_subsys operatoin ->css_e_css_changed(). This is
invoked if any of the effective csses seen from the css's cgroup may
have changed. This will be used to implement cgroup writeback
support.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Zefan Li <lizefan@huawei.com>
Diffstat (limited to 'kernel/cgroup.c')
-rw-r--r-- | kernel/cgroup.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index c8558693102b..69f033582a1a 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c | |||
@@ -2836,6 +2836,24 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of, | |||
2836 | } | 2836 | } |
2837 | } | 2837 | } |
2838 | 2838 | ||
2839 | /* | ||
2840 | * The effective csses of all the descendants (excluding @cgrp) may | ||
2841 | * have changed. Subsystems can optionally subscribe to this event | ||
2842 | * by implementing ->css_e_css_changed() which is invoked if any of | ||
2843 | * the effective csses seen from the css's cgroup may have changed. | ||
2844 | */ | ||
2845 | for_each_subsys(ss, ssid) { | ||
2846 | struct cgroup_subsys_state *this_css = cgroup_css(cgrp, ss); | ||
2847 | struct cgroup_subsys_state *css; | ||
2848 | |||
2849 | if (!ss->css_e_css_changed || !this_css) | ||
2850 | continue; | ||
2851 | |||
2852 | css_for_each_descendant_pre(css, this_css) | ||
2853 | if (css != this_css) | ||
2854 | ss->css_e_css_changed(css); | ||
2855 | } | ||
2856 | |||
2839 | kernfs_activate(cgrp->kn); | 2857 | kernfs_activate(cgrp->kn); |
2840 | ret = 0; | 2858 | ret = 0; |
2841 | out_unlock: | 2859 | out_unlock: |