This adds a macro to get the css of a tset (using task_get_css()) by just grabbing a ref to the first item in the tset (since there is a guarantee that all tasks in a tset share a css). This is in preparation for implementing the pids cgroup subsystem. Signed-off-by: Aleksa Sarai <cyphar@xxxxxxxxxx> --- include/linux/cgroup.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 886a883..773846d 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -639,6 +639,18 @@ struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset); for ((task) = cgroup_taskset_first((tset)); (task); \ (task) = cgroup_taskset_next((tset))) +/** + * tset_get_css - obtain and get css for (tset, subsys_id) + * @tset: target taskset + * @subsys_id: target subsystem id + * + * Since all of the tasks in a taskset are guaranteed to have the same css, it's + * safe to grab the ref of just the first task's css and treat it as though you + * have a ref on the taskset's "collective" css. + */ +#define tset_get_css(tset, subsys_id) \ + task_get_css(cgroup_taskset_first(tset), subsys_id) + /* * Control Group subsystem type. * See Documentation/cgroups/cgroups.txt for details -- 2.4.1 -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
