include/net/cls_cgroup.h

   1 /*
   2  * cls_cgroup.h                 Control Group Classifier
   3  *
   4  * Authors:     Thomas Graf <tgraf@suug.ch>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  */
  12
  13 #ifndef _NET_CLS_CGROUP_H
  14 #define _NET_CLS_CGROUP_H
  15
  16 #include <linux/cgroup.h>
  17 #include <linux/hardirq.h>
  18 #include <linux/rcupdate.h>
  19
  20 #ifdef CONFIG_CGROUPS
  21 struct cgroup_cls_state
  22 {
  23         struct cgroup_subsys_state css;
  24         u32 classid;
  25 };
  26
  27 #ifdef CONFIG_NET_CLS_CGROUP
  28 static inline u32 task_cls_classid(struct task_struct *p)
  29 {
  30         if (in_interrupt())
  31                 return 0;
  32
  33         return container_of(task_subsys_state(p, net_cls_subsys_id),
  34                             struct cgroup_cls_state, css)->classid;
  35 }
  36 #else
  37 extern int net_cls_subsys_id;
  38
  39 static inline u32 task_cls_classid(struct task_struct *p)
  40 {
  41         int id;
  42         u32 classid = 0;
  43
  44         if (in_interrupt())
  45                 return 0;
  46
  47         rcu_read_lock();
  48         id = rcu_dereference(net_cls_subsys_id);
  49         if (id >= 0)
  50                 classid = container_of(task_subsys_state(p, id),
  51                                        struct cgroup_cls_state, css)->classid;
  52         rcu_read_unlock();
  53
  54         return classid;
  55 }
  56 #endif
  57 #else
  58 static inline u32 task_cls_classid(struct task_struct *p)
  59 {
  60         return 0;
  61 }
  62 #endif
  63 #endif  /* _NET_CLS_CGROUP_H */