Re: [PATCHv1 3/8] cgroup: add function to get task's cgroup on default hierarchy
From: Serge E. Hallyn <hidden>
Date: 2014-10-16 16:13:28
Also in:
cgroups, lkml
Quoting Aditya Kali (adityakali-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org):
get_task_cgroup() returns the (reference counted) cgroup of the given task on the default hierarchy. Signed-off-by: Aditya Kali <redacted>
Acked-by: Serge Hallyn <redacted>
quoted hunk ↗ jump to hunk
--- include/linux/cgroup.h | 1 + kernel/cgroup.c | 25 +++++++++++++++++++++++++ 2 files changed, 26 insertions(+)diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 1d51968..80ed6e0 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h@@ -579,6 +579,7 @@ static inline void pr_cont_cgroup_path(struct cgroup *cgrp) } char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen); +struct cgroup *get_task_cgroup(struct task_struct *task); int cgroup_add_dfl_cftypes(struct cgroup_subsys *ss, struct cftype *cfts); int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);diff --git a/kernel/cgroup.c b/kernel/cgroup.c index cab7dc4..56d507b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c@@ -1916,6 +1916,31 @@ char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen) } EXPORT_SYMBOL_GPL(task_cgroup_path); +/* + * get_task_cgroup - returns the cgroup of the task in the default cgroup + * hierarchy. + * + * @task: target task + * This function returns the @task's cgroup on the default cgroup hierarchy. The + * returned cgroup has its reference incremented (by calling cgroup_get()). So + * the caller must cgroup_put() the obtained reference once it is done with it. + */ +struct cgroup *get_task_cgroup(struct task_struct *task) +{ + struct cgroup *cgrp; + + mutex_lock(&cgroup_mutex); + down_read(&css_set_rwsem); + + cgrp = task_cgroup_from_root(task, &cgrp_dfl_root); + cgroup_get(cgrp); + + up_read(&css_set_rwsem); + mutex_unlock(&cgroup_mutex); + return cgrp; +} +EXPORT_SYMBOL_GPL(get_task_cgroup); + /* used to track tasks and other necessary states during migration */ struct cgroup_taskset { /* the src and dst cset list running through cset->mg_node */-- 2.1.0.rc2.206.gedb03e5 _______________________________________________ Containers mailing list Containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org https://lists.linuxfoundation.org/mailman/listinfo/containers