linux/include/net/netns/packet.h

/*
 * Packet network namespace
 */
#ifndef __NETNS_PACKET_H__
#define __NETNS_PACKET_H__

#include <linux/rculist.h>
#include <linux/mutex.h>

struct netns_packet {
	struct mutex		sklist_lock;
	struct hlist_head	sklist;
};

#endif /* __NETNS_PACKET_H__ */
[NETNS]: separate af_packet netns data Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> 2007-12-11 12:19:54 +00:00			`/*`
			`* Packet network namespace`
			`*/`
			`#ifndef __NETNS_PACKET_H__`
			`#define __NETNS_PACKET_H__`

packet: convert socket list to RCU (v3) Convert AF_PACKET to use RCU, eliminating one more reader/writer lock. There is no need for a real sk_del_node_init_rcu(), because sk_del_node_init is doing the equivalent thing to hlst_del_init_rcu already; but added some comments to try and make that obvious. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2010-02-22 07:57:18 +00:00			`#include <linux/rculist.h>`
packet: fix broken build. This patch fixes a broken build due to a missing header: ... CC net/ipv4/proc.o In file included from include/net/net_namespace.h:15, from net/ipv4/proc.c:35: include/net/netns/packet.h:11: error: field 'sklist_lock' has incomplete type ... The lock of netns_packet has been replaced by a recent patch to be a mutex instead of a spinlock, but we need to replace the header file to be linux/mutex.h instead of linux/spinlock.h as well. See commit 0fa7fa98dbcc2789409ed24e885485e645803d7f: packet: Protect packet sk list with mutex (v2) patch, Signed-off-by: Rami Rosen <rosenr@marvell.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2012-08-23 02:55:41 +00:00			`#include <linux/mutex.h>`
[NETNS]: separate af_packet netns data Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> 2007-12-11 12:19:54 +00:00
			`struct netns_packet {`
packet: Protect packet sk list with mutex (v2) Change since v1: * Fixed inuse counters access spotted by Eric In patch eea68e2f (packet: Report socket mclist info via diag module) I've introduced a "scheduling in atomic" problem in packet diag module -- the socket list is traversed under rcu_read_lock() while performed under it sk mclist access requires rtnl lock (i.e. -- mutex) to be taken. [152363.820563] BUG: scheduling while atomic: crtools/12517/0x10000002 [152363.820573] 4 locks held by crtools/12517: [152363.820581] #0: (sock_diag_mutex){+.+.+.}, at: [<ffffffff81a2dcb5>] sock_diag_rcv+0x1f/0x3e [152363.820613] #1: (sock_diag_table_mutex){+.+.+.}, at: [<ffffffff81a2de70>] sock_diag_rcv_msg+0xdb/0x11a [152363.820644] #2: (nlk->cb_mutex){+.+.+.}, at: [<ffffffff81a67d01>] netlink_dump+0x23/0x1ab [152363.820693] #3: (rcu_read_lock){.+.+..}, at: [<ffffffff81b6a049>] packet_diag_dump+0x0/0x1af Similar thing was then re-introduced by further packet diag patches (fanount mutex and pgvec mutex for rings) :( Apart from being terribly sorry for the above, I propose to change the packet sk list protection from spinlock to mutex. This lock currently protects two modifications: * sklist * prot inuse counters The sklist modifications can be just reprotected with mutex since they already occur in a sleeping context. The inuse counters modifications are trickier -- the __this_cpu_-s are used inside, thus requiring the caller to handle the potential issues with contexts himself. Since packet sockets' counters are modified in two places only (packet_create and packet_release) we only need to protect the context from being preempted. BH disabling is not required in this case. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2012-08-21 01:06:47 +00:00			`struct mutex sklist_lock;`
[NETNS]: separate af_packet netns data Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> 2007-12-11 12:19:54 +00:00			`struct hlist_head sklist;`
			`};`

			`#endif /* __NETNS_PACKET_H__ */`