alistair23-linux/include/net/cls_cgroup.h
Tejun Heo 2a56a1fec2 net: wrap sock->sk_cgrp_prioidx and ->sk_classid inside a struct
Introduce sock->sk_cgrp_data which is a struct sock_cgroup_data.
->sk_cgroup_prioidx and ->sk_classid are moved into it.  The struct
and its accessors are defined in cgroup-defs.h.  This is to prepare
for overloading the fields with a cgroup pointer.

This patch mostly performs equivalent conversions but the followings
are noteworthy.

* Equality test before updating classid is removed from
  sock_update_classid().  This shouldn't make any noticeable
  difference and a similar test will be implemented on the helper side
  later.

* sock_update_netprioidx() now takes struct sock_cgroup_data and can
  be moved to netprio_cgroup.h without causing include dependency
  loop.  Moved.

* The dummy version of sock_update_netprioidx() converted to a static
  inline function while at it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-08 22:02:33 -05:00

86 lines
2.1 KiB
C

/*
* cls_cgroup.h Control Group Classifier
*
* Authors: Thomas Graf <tgraf@suug.ch>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#ifndef _NET_CLS_CGROUP_H
#define _NET_CLS_CGROUP_H
#include <linux/cgroup.h>
#include <linux/hardirq.h>
#include <linux/rcupdate.h>
#include <net/sock.h>
#ifdef CONFIG_CGROUP_NET_CLASSID
struct cgroup_cls_state {
struct cgroup_subsys_state css;
u32 classid;
};
struct cgroup_cls_state *task_cls_state(struct task_struct *p);
static inline u32 task_cls_classid(struct task_struct *p)
{
u32 classid;
if (in_interrupt())
return 0;
rcu_read_lock();
classid = container_of(task_css(p, net_cls_cgrp_id),
struct cgroup_cls_state, css)->classid;
rcu_read_unlock();
return classid;
}
static inline void sock_update_classid(struct sock_cgroup_data *skcd)
{
u32 classid;
classid = task_cls_classid(current);
sock_cgroup_set_classid(skcd, classid);
}
static inline u32 task_get_classid(const struct sk_buff *skb)
{
u32 classid = task_cls_state(current)->classid;
/* Due to the nature of the classifier it is required to ignore all
* packets originating from softirq context as accessing `current'
* would lead to false results.
*
* This test assumes that all callers of dev_queue_xmit() explicitly
* disable bh. Knowing this, it is possible to detect softirq based
* calls by looking at the number of nested bh disable calls because
* softirqs always disables bh.
*/
if (in_serving_softirq()) {
/* If there is an sock_cgroup_classid we'll use that. */
if (!skb->sk)
return 0;
classid = sock_cgroup_classid(&skb->sk->sk_cgrp_data);
}
return classid;
}
#else /* !CONFIG_CGROUP_NET_CLASSID */
static inline void sock_update_classid(struct sock_cgroup_data *skcd)
{
}
static inline u32 task_get_classid(const struct sk_buff *skb)
{
return 0;
}
#endif /* CONFIG_CGROUP_NET_CLASSID */
#endif /* _NET_CLS_CGROUP_H */