diff options
Diffstat (limited to 'include/linux/cgroup.h')
| -rw-r--r-- | include/linux/cgroup.h | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 2357733a0a80..88e863460726 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -141,15 +141,36 @@ enum { CGRP_WAIT_ON_RMDIR, }; +/* which pidlist file are we talking about? */ +enum cgroup_filetype { + CGROUP_FILE_PROCS, + CGROUP_FILE_TASKS, +}; + +/* + * A pidlist is a list of pids that virtually represents the contents of one + * of the cgroup files ("procs" or "tasks"). We keep a list of such pidlists, + * a pair (one each for procs, tasks) for each pid namespace that's relevant + * to the cgroup. + */ struct cgroup_pidlist { - /* protects the other fields */ - struct rw_semaphore mutex; + /* + * used to find which pidlist is wanted. doesn't change as long as + * this particular list stays in the list. + */ + struct { enum cgroup_filetype type; struct pid_namespace *ns; } key; /* array of xids */ pid_t *list; /* how many elements the above list has */ int length; /* how many files are using the current array */ int use_count; + /* each of these stored in a list by its cgroup */ + struct list_head links; + /* pointer to the cgroup we belong to, for list removal purposes */ + struct cgroup *owner; + /* protects the other fields */ + struct rw_semaphore mutex; }; struct cgroup { @@ -190,9 +211,12 @@ struct cgroup { */ struct list_head release_list; - /* we will have two separate pidlists, one for pids (the tasks file) - * and one for tgids (the procs file). */ - struct cgroup_pidlist tasks, procs; + /* + * list of pidlists, up to two for each namespace (one for procs, one + * for tasks); created on demand. + */ + struct list_head pidlists; + struct mutex pidlist_mutex; /* For RCU-protected deletion */ struct rcu_head rcu_head; |