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         int classid;
  31
  32         if (in_interrupt())
  33                 return 0;
  34
  35         rcu_read_lock();
  36         classid = container_of(task_subsys_state(p, net_cls_subsys_id),
  37                                struct cgroup_cls_state, css)->classid;
  38         rcu_read_unlock();
  39
  40         return classid;
  41 }
  42 #else
  43 extern int net_cls_subsys_id;
  44
  45 static inline u32 task_cls_classid(struct task_struct *p)
  46 {
  47         int id;
  48         u32 classid = 0;
  49
  50         if (in_interrupt())
  51                 return 0;
  52
  53         rcu_read_lock();
  54         id = rcu_dereference_index_check(net_cls_subsys_id,
  55                                          rcu_read_lock_held());
  56         if (id >= 0)
  57                 classid = container_of(task_subsys_state(p, id),
  58                                        struct cgroup_cls_state, css)->classid;
  59         rcu_read_unlock();
  60
  61         return classid;
  62 }
  63 #endif
  64 #else
  65 static inline u32 task_cls_classid(struct task_struct *p)
  66 {
  67         return 0;
  68 }
  69 #endif
  70 #endif  /* _NET_CLS_CGROUP_H */