linux_dsm_epyc7002/net/tipc/msg.h

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/*
* net/tipc/msg.h: Include file for TIPC message header routines
*
* Copyright (c) 2000-2007, 2014-2015 Ericsson AB
* Copyright (c) 2005-2008, 2010-2011, Wind River Systems
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _TIPC_MSG_H
#define _TIPC_MSG_H
#include <linux/tipc.h>
#include "core.h"
/*
* Constants and routines used to read and write TIPC payload message headers
*
* Note: Some items are also used with TIPC internal message headers
*/
#define TIPC_VERSION 2
tipc: resolve race problem at unicast message reception TIPC handles message cardinality and sequencing at the link layer, before passing messages upwards to the destination sockets. During the upcall from link to socket no locks are held. It is therefore possible, and we see it happen occasionally, that messages arriving in different threads and delivered in sequence still bypass each other before they reach the destination socket. This must not happen, since it violates the sequentiality guarantee. We solve this by adding a new input buffer queue to the link structure. Arriving messages are added safely to the tail of that queue by the link, while the head of the queue is consumed, also safely, by the receiving socket. Sequentiality is secured per socket by only allowing buffers to be dequeued inside the socket lock. Since there may be multiple simultaneous readers of the queue, we use a 'filter' parameter to reduce the risk that they peek the same buffer from the queue, hence also reducing the risk of contention on the receiving socket locks. This solves the sequentiality problem, and seems to cause no measurable performance degradation. A nice side effect of this change is that lock handling in the functions tipc_rcv() and tipc_bcast_rcv() now becomes uniform, something that will enable future simplifications of those functions. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 20:36:41 +07:00
struct plist;
/*
* Payload message users are defined in TIPC's public API:
* - TIPC_LOW_IMPORTANCE
* - TIPC_MEDIUM_IMPORTANCE
* - TIPC_HIGH_IMPORTANCE
* - TIPC_CRITICAL_IMPORTANCE
*/
tipc: clean up handling of message priorities Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-14 03:08:11 +07:00
#define TIPC_SYSTEM_IMPORTANCE 4
/*
* Payload message types
*/
#define TIPC_CONN_MSG 0
#define TIPC_MCAST_MSG 1
#define TIPC_NAMED_MSG 2
#define TIPC_DIRECT_MSG 3
tipc: clean up handling of message priorities Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-14 03:08:11 +07:00
/*
* Internal message users
*/
#define BCAST_PROTOCOL 5
#define MSG_BUNDLER 6
#define LINK_PROTOCOL 7
#define CONN_MANAGER 8
#define TUNNEL_PROTOCOL 10
tipc: clean up handling of message priorities Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-14 03:08:11 +07:00
#define NAME_DISTRIBUTOR 11
#define MSG_FRAGMENTER 12
#define LINK_CONFIG 13
#define SOCK_WAKEUP 14 /* pseudo user */
/*
* Message header sizes
*/
#define SHORT_H_SIZE 24 /* In-cluster basic payload message */
#define BASIC_H_SIZE 32 /* Basic payload message */
#define NAMED_H_SIZE 40 /* Named payload message */
#define MCAST_H_SIZE 44 /* Multicast payload message */
#define INT_H_SIZE 40 /* Internal messages */
#define MIN_H_SIZE 24 /* Smallest legal TIPC header size */
#define MAX_H_SIZE 60 /* Largest possible TIPC header size */
#define MAX_MSG_SIZE (MAX_H_SIZE + TIPC_MAX_USER_MSG_SIZE)
#define TIPC_MEDIA_INFO_OFFSET 5
/**
* TIPC message buffer code
*
* TIPC message buffer headroom reserves space for the worst-case
* link-level device header (in case the message is sent off-node).
*
* Note: Headroom should be a multiple of 4 to ensure the TIPC header fields
* are word aligned for quicker access
*/
#define BUF_HEADROOM (LL_MAX_HEADER + 48)
struct tipc_skb_cb {
void *handle;
struct sk_buff *tail;
bool validated;
bool wakeup_pending;
u16 chain_sz;
u16 chain_imp;
u16 ackers;
};
#define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
struct tipc_msg {
__be32 hdr[15];
};
static inline struct tipc_msg *buf_msg(struct sk_buff *skb)
{
return (struct tipc_msg *)skb->data;
}
static inline u32 msg_word(struct tipc_msg *m, u32 pos)
{
return ntohl(m->hdr[pos]);
}
static inline void msg_set_word(struct tipc_msg *m, u32 w, u32 val)
{
m->hdr[w] = htonl(val);
}
static inline u32 msg_bits(struct tipc_msg *m, u32 w, u32 pos, u32 mask)
{
return (msg_word(m, w) >> pos) & mask;
}
static inline void msg_set_bits(struct tipc_msg *m, u32 w,
u32 pos, u32 mask, u32 val)
{
val = (val & mask) << pos;
mask = mask << pos;
m->hdr[w] &= ~htonl(mask);
m->hdr[w] |= htonl(val);
}
static inline void msg_swap_words(struct tipc_msg *msg, u32 a, u32 b)
{
u32 temp = msg->hdr[a];
msg->hdr[a] = msg->hdr[b];
msg->hdr[b] = temp;
}
/*
* Word 0
*/
static inline u32 msg_version(struct tipc_msg *m)
{
return msg_bits(m, 0, 29, 7);
}
static inline void msg_set_version(struct tipc_msg *m)
{
msg_set_bits(m, 0, 29, 7, TIPC_VERSION);
}
static inline u32 msg_user(struct tipc_msg *m)
{
return msg_bits(m, 0, 25, 0xf);
}
static inline u32 msg_isdata(struct tipc_msg *m)
{
return msg_user(m) <= TIPC_CRITICAL_IMPORTANCE;
}
static inline void msg_set_user(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 0, 25, 0xf, n);
}
static inline u32 msg_hdr_sz(struct tipc_msg *m)
{
return msg_bits(m, 0, 21, 0xf) << 2;
}
static inline void msg_set_hdr_sz(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 0, 21, 0xf, n>>2);
}
static inline u32 msg_size(struct tipc_msg *m)
{
return msg_bits(m, 0, 0, 0x1ffff);
}
static inline u32 msg_data_sz(struct tipc_msg *m)
{
return msg_size(m) - msg_hdr_sz(m);
}
static inline int msg_non_seq(struct tipc_msg *m)
{
return msg_bits(m, 0, 20, 1);
}
static inline void msg_set_non_seq(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 0, 20, 1, n);
}
static inline int msg_dest_droppable(struct tipc_msg *m)
{
return msg_bits(m, 0, 19, 1);
}
static inline void msg_set_dest_droppable(struct tipc_msg *m, u32 d)
{
msg_set_bits(m, 0, 19, 1, d);
}
static inline int msg_src_droppable(struct tipc_msg *m)
{
return msg_bits(m, 0, 18, 1);
}
static inline void msg_set_src_droppable(struct tipc_msg *m, u32 d)
{
msg_set_bits(m, 0, 18, 1, d);
}
static inline void msg_set_size(struct tipc_msg *m, u32 sz)
{
m->hdr[0] = htonl((msg_word(m, 0) & ~0x1ffff) | sz);
}
static inline unchar *msg_data(struct tipc_msg *m)
{
return ((unchar *)m) + msg_hdr_sz(m);
}
static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m)
{
return (struct tipc_msg *)msg_data(m);
}
/*
* Word 1
*/
static inline u32 msg_type(struct tipc_msg *m)
{
return msg_bits(m, 1, 29, 0x7);
}
static inline void msg_set_type(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 29, 0x7, n);
}
static inline u32 msg_named(struct tipc_msg *m)
{
return msg_type(m) == TIPC_NAMED_MSG;
}
static inline u32 msg_mcast(struct tipc_msg *m)
{
return msg_type(m) == TIPC_MCAST_MSG;
}
static inline u32 msg_connected(struct tipc_msg *m)
{
return msg_type(m) == TIPC_CONN_MSG;
}
static inline u32 msg_errcode(struct tipc_msg *m)
{
return msg_bits(m, 1, 25, 0xf);
}
static inline void msg_set_errcode(struct tipc_msg *m, u32 err)
{
msg_set_bits(m, 1, 25, 0xf, err);
}
static inline u32 msg_reroute_cnt(struct tipc_msg *m)
{
return msg_bits(m, 1, 21, 0xf);
}
static inline void msg_incr_reroute_cnt(struct tipc_msg *m)
{
msg_set_bits(m, 1, 21, 0xf, msg_reroute_cnt(m) + 1);
}
static inline void msg_reset_reroute_cnt(struct tipc_msg *m)
{
msg_set_bits(m, 1, 21, 0xf, 0);
}
static inline u32 msg_lookup_scope(struct tipc_msg *m)
{
return msg_bits(m, 1, 19, 0x3);
}
static inline void msg_set_lookup_scope(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 19, 0x3, n);
}
static inline u16 msg_bcast_ack(struct tipc_msg *m)
{
return msg_bits(m, 1, 0, 0xffff);
}
static inline void msg_set_bcast_ack(struct tipc_msg *m, u16 n)
{
msg_set_bits(m, 1, 0, 0xffff, n);
}
/*
* Word 2
*/
static inline u16 msg_ack(struct tipc_msg *m)
{
return msg_bits(m, 2, 16, 0xffff);
}
static inline void msg_set_ack(struct tipc_msg *m, u16 n)
{
msg_set_bits(m, 2, 16, 0xffff, n);
}
static inline u16 msg_seqno(struct tipc_msg *m)
{
return msg_bits(m, 2, 0, 0xffff);
}
static inline void msg_set_seqno(struct tipc_msg *m, u16 n)
{
msg_set_bits(m, 2, 0, 0xffff, n);
}
/*
* Words 3-10
*/
tipc: clean up handling of message priorities Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-14 03:08:11 +07:00
static inline u32 msg_importance(struct tipc_msg *m)
{
tipc: improve link congestion algorithm The link congestion algorithm used until now implies two problems. - It is too generous towards lower-level messages in situations of high load by giving "absolute" bandwidth guarantees to the different priority levels. LOW traffic is guaranteed 10%, MEDIUM is guaranted 20%, HIGH is guaranteed 30%, and CRITICAL is guaranteed 40% of the available bandwidth. But, in the absence of higher level traffic, the ratio between two distinct levels becomes unreasonable. E.g. if there is only LOW and MEDIUM traffic on a system, the former is guaranteed 1/3 of the bandwidth, and the latter 2/3. This again means that if there is e.g. one LOW user and 10 MEDIUM users, the former will have 33.3% of the bandwidth, and the others will have to compete for the remainder, i.e. each will end up with 6.7% of the capacity. - Packets of type MSG_BUNDLER are created at SYSTEM importance level, but only after the packets bundled into it have passed the congestion test for their own respective levels. Since bundled packets don't result in incrementing the level counter for their own importance, only occasionally for the SYSTEM level counter, they do in practice obtain SYSTEM level importance. Hence, the current implementation provides a gap in the congestion algorithm that in the worst case may lead to a link reset. We now refine the congestion algorithm as follows: - A message is accepted to the link backlog only if its own level counter, and all superior level counters, permit it. - The importance of a created bundle packet is set according to its contents. A bundle packet created from messges at levels LOW to CRITICAL is given importance level CRITICAL, while a bundle created from a SYSTEM level message is given importance SYSTEM. In the latter case only subsequent SYSTEM level messages are allowed to be bundled into it. This solves the first problem described above, by making the bandwidth guarantee relative to the total number of users at all levels; only the upper limit for each level remains absolute. In the example described above, the single LOW user would use 1/11th of the bandwidth, the same as each of the ten MEDIUM users, but he still has the same guarantee against starvation as the latter ones. The fix also solves the second problem. If the CRITICAL level is filled up by bundle packets of that level, no lower level packets will be accepted any more. Suggested-by: Gergely Kiss <gergely.kiss@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14 21:46:17 +07:00
int usr = msg_user(m);
if (likely((usr <= TIPC_CRITICAL_IMPORTANCE) && !msg_errcode(m)))
return usr;
if ((usr == MSG_FRAGMENTER) || (usr == MSG_BUNDLER))
return msg_bits(m, 9, 0, 0x7);
tipc: clean up handling of message priorities Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-14 03:08:11 +07:00
return TIPC_SYSTEM_IMPORTANCE;
}
static inline void msg_set_importance(struct tipc_msg *m, u32 i)
{
tipc: improve link congestion algorithm The link congestion algorithm used until now implies two problems. - It is too generous towards lower-level messages in situations of high load by giving "absolute" bandwidth guarantees to the different priority levels. LOW traffic is guaranteed 10%, MEDIUM is guaranted 20%, HIGH is guaranteed 30%, and CRITICAL is guaranteed 40% of the available bandwidth. But, in the absence of higher level traffic, the ratio between two distinct levels becomes unreasonable. E.g. if there is only LOW and MEDIUM traffic on a system, the former is guaranteed 1/3 of the bandwidth, and the latter 2/3. This again means that if there is e.g. one LOW user and 10 MEDIUM users, the former will have 33.3% of the bandwidth, and the others will have to compete for the remainder, i.e. each will end up with 6.7% of the capacity. - Packets of type MSG_BUNDLER are created at SYSTEM importance level, but only after the packets bundled into it have passed the congestion test for their own respective levels. Since bundled packets don't result in incrementing the level counter for their own importance, only occasionally for the SYSTEM level counter, they do in practice obtain SYSTEM level importance. Hence, the current implementation provides a gap in the congestion algorithm that in the worst case may lead to a link reset. We now refine the congestion algorithm as follows: - A message is accepted to the link backlog only if its own level counter, and all superior level counters, permit it. - The importance of a created bundle packet is set according to its contents. A bundle packet created from messges at levels LOW to CRITICAL is given importance level CRITICAL, while a bundle created from a SYSTEM level message is given importance SYSTEM. In the latter case only subsequent SYSTEM level messages are allowed to be bundled into it. This solves the first problem described above, by making the bandwidth guarantee relative to the total number of users at all levels; only the upper limit for each level remains absolute. In the example described above, the single LOW user would use 1/11th of the bandwidth, the same as each of the ten MEDIUM users, but he still has the same guarantee against starvation as the latter ones. The fix also solves the second problem. If the CRITICAL level is filled up by bundle packets of that level, no lower level packets will be accepted any more. Suggested-by: Gergely Kiss <gergely.kiss@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14 21:46:17 +07:00
int usr = msg_user(m);
if (likely((usr == MSG_FRAGMENTER) || (usr == MSG_BUNDLER)))
msg_set_bits(m, 9, 0, 0x7, i);
tipc: improve link congestion algorithm The link congestion algorithm used until now implies two problems. - It is too generous towards lower-level messages in situations of high load by giving "absolute" bandwidth guarantees to the different priority levels. LOW traffic is guaranteed 10%, MEDIUM is guaranted 20%, HIGH is guaranteed 30%, and CRITICAL is guaranteed 40% of the available bandwidth. But, in the absence of higher level traffic, the ratio between two distinct levels becomes unreasonable. E.g. if there is only LOW and MEDIUM traffic on a system, the former is guaranteed 1/3 of the bandwidth, and the latter 2/3. This again means that if there is e.g. one LOW user and 10 MEDIUM users, the former will have 33.3% of the bandwidth, and the others will have to compete for the remainder, i.e. each will end up with 6.7% of the capacity. - Packets of type MSG_BUNDLER are created at SYSTEM importance level, but only after the packets bundled into it have passed the congestion test for their own respective levels. Since bundled packets don't result in incrementing the level counter for their own importance, only occasionally for the SYSTEM level counter, they do in practice obtain SYSTEM level importance. Hence, the current implementation provides a gap in the congestion algorithm that in the worst case may lead to a link reset. We now refine the congestion algorithm as follows: - A message is accepted to the link backlog only if its own level counter, and all superior level counters, permit it. - The importance of a created bundle packet is set according to its contents. A bundle packet created from messges at levels LOW to CRITICAL is given importance level CRITICAL, while a bundle created from a SYSTEM level message is given importance SYSTEM. In the latter case only subsequent SYSTEM level messages are allowed to be bundled into it. This solves the first problem described above, by making the bandwidth guarantee relative to the total number of users at all levels; only the upper limit for each level remains absolute. In the example described above, the single LOW user would use 1/11th of the bandwidth, the same as each of the ten MEDIUM users, but he still has the same guarantee against starvation as the latter ones. The fix also solves the second problem. If the CRITICAL level is filled up by bundle packets of that level, no lower level packets will be accepted any more. Suggested-by: Gergely Kiss <gergely.kiss@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14 21:46:17 +07:00
else if (i < TIPC_SYSTEM_IMPORTANCE)
tipc: clean up handling of message priorities Messages transferred by TIPC are assigned an "importance priority", -an integer value indicating how to treat the message when there is link or destination socket congestion. There is no separate header field for this value. Instead, the message user values have been chosen in ascending order according to perceived importance, so that the message user field can be used for this. This is not a good solution. First, we have many more users than the needed priority levels, so we end up with treating more priority levels than necessary. Second, the user field cannot always accurately reflect the priority of the message. E.g., a message fragment packet should really have the priority of the enveloped user data message, and not the priority of the MSG_FRAGMENTER user. Until now, we have been working around this problem in different ways, but it is now time to implement a consistent way of handling such priorities, although still within the constraint that we cannot allocate any more bits in the regular data message header for this. In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE, that will be the only one used apart from the four (lower) user data levels. All non-data messages map down to this priority. Furthermore, we take some free bits from the MSG_FRAGMENTER header and allocate them to store the priority of the enveloped message. We then adjust the functions msg_importance()/msg_set_importance() so that they read/set the correct header fields depending on user type. This small protocol change is fully compatible, because the code at the receiving end of a link currently reads the importance level only from user data messages, where there is no change. Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-14 03:08:11 +07:00
msg_set_user(m, i);
else
pr_warn("Trying to set illegal importance in message\n");
}
static inline u32 msg_prevnode(struct tipc_msg *m)
{
return msg_word(m, 3);
}
static inline void msg_set_prevnode(struct tipc_msg *m, u32 a)
{
msg_set_word(m, 3, a);
}
static inline u32 msg_origport(struct tipc_msg *m)
{
if (msg_user(m) == MSG_FRAGMENTER)
m = msg_get_wrapped(m);
return msg_word(m, 4);
}
static inline void msg_set_origport(struct tipc_msg *m, u32 p)
{
msg_set_word(m, 4, p);
}
static inline u32 msg_destport(struct tipc_msg *m)
{
return msg_word(m, 5);
}
static inline void msg_set_destport(struct tipc_msg *m, u32 p)
{
msg_set_word(m, 5, p);
}
static inline u32 msg_mc_netid(struct tipc_msg *m)
{
return msg_word(m, 5);
}
static inline void msg_set_mc_netid(struct tipc_msg *m, u32 p)
{
msg_set_word(m, 5, p);
}
static inline int msg_short(struct tipc_msg *m)
{
return msg_hdr_sz(m) == SHORT_H_SIZE;
}
static inline u32 msg_orignode(struct tipc_msg *m)
{
if (likely(msg_short(m)))
return msg_prevnode(m);
return msg_word(m, 6);
}
static inline void msg_set_orignode(struct tipc_msg *m, u32 a)
{
msg_set_word(m, 6, a);
}
static inline u32 msg_destnode(struct tipc_msg *m)
{
return msg_word(m, 7);
}
static inline void msg_set_destnode(struct tipc_msg *m, u32 a)
{
msg_set_word(m, 7, a);
}
static inline u32 msg_nametype(struct tipc_msg *m)
{
return msg_word(m, 8);
}
static inline void msg_set_nametype(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 8, n);
}
static inline u32 msg_nameinst(struct tipc_msg *m)
{
return msg_word(m, 9);
}
static inline u32 msg_namelower(struct tipc_msg *m)
{
return msg_nameinst(m);
}
static inline void msg_set_namelower(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 9, n);
}
static inline void msg_set_nameinst(struct tipc_msg *m, u32 n)
{
msg_set_namelower(m, n);
}
static inline u32 msg_nameupper(struct tipc_msg *m)
{
return msg_word(m, 10);
}
static inline void msg_set_nameupper(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 10, n);
}
/*
* Constants and routines used to read and write TIPC internal message headers
*/
/*
* Connection management protocol message types
*/
#define CONN_PROBE 0
#define CONN_PROBE_REPLY 1
#define CONN_ACK 2
/*
* Name distributor message types
*/
#define PUBLICATION 0
#define WITHDRAWAL 1
/*
* Segmentation message types
*/
#define FIRST_FRAGMENT 0
#define FRAGMENT 1
#define LAST_FRAGMENT 2
/*
* Link management protocol message types
*/
#define STATE_MSG 0
#define RESET_MSG 1
#define ACTIVATE_MSG 2
/*
* Changeover tunnel message types
*/
#define SYNCH_MSG 0
#define FAILOVER_MSG 1
/*
* Config protocol message types
*/
#define DSC_REQ_MSG 0
#define DSC_RESP_MSG 1
/*
* Word 1
*/
static inline u32 msg_seq_gap(struct tipc_msg *m)
{
return msg_bits(m, 1, 16, 0x1fff);
}
static inline void msg_set_seq_gap(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 16, 0x1fff, n);
}
static inline u32 msg_node_sig(struct tipc_msg *m)
{
return msg_bits(m, 1, 0, 0xffff);
}
static inline void msg_set_node_sig(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 0, 0xffff, n);
}
static inline u32 msg_node_capabilities(struct tipc_msg *m)
{
return msg_bits(m, 1, 15, 0x1fff);
}
static inline void msg_set_node_capabilities(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 1, 15, 0x1fff, n);
}
/*
* Word 2
*/
static inline u32 msg_dest_domain(struct tipc_msg *m)
{
return msg_word(m, 2);
}
static inline void msg_set_dest_domain(struct tipc_msg *m, u32 n)
{
msg_set_word(m, 2, n);
}
static inline u32 msg_bcgap_after(struct tipc_msg *m)
{
return msg_bits(m, 2, 16, 0xffff);
}
static inline void msg_set_bcgap_after(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 2, 16, 0xffff, n);
}
static inline u32 msg_bcgap_to(struct tipc_msg *m)
{
return msg_bits(m, 2, 0, 0xffff);
}
static inline void msg_set_bcgap_to(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 2, 0, 0xffff, n);
}
/*
* Word 4
*/
static inline u32 msg_last_bcast(struct tipc_msg *m)
{
return msg_bits(m, 4, 16, 0xffff);
}
static inline u32 msg_bc_snd_nxt(struct tipc_msg *m)
{
return msg_last_bcast(m) + 1;
}
static inline void msg_set_last_bcast(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 16, 0xffff, n);
}
static inline void msg_set_fragm_no(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 16, 0xffff, n);
}
static inline u16 msg_next_sent(struct tipc_msg *m)
{
return msg_bits(m, 4, 0, 0xffff);
}
static inline void msg_set_next_sent(struct tipc_msg *m, u16 n)
{
msg_set_bits(m, 4, 0, 0xffff, n);
}
static inline void msg_set_long_msgno(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 0, 0xffff, n);
}
static inline u32 msg_bc_netid(struct tipc_msg *m)
{
return msg_word(m, 4);
}
static inline void msg_set_bc_netid(struct tipc_msg *m, u32 id)
{
msg_set_word(m, 4, id);
}
static inline u32 msg_link_selector(struct tipc_msg *m)
{
return msg_bits(m, 4, 0, 1);
}
static inline void msg_set_link_selector(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 4, 0, 1, n);
}
/*
* Word 5
*/
static inline u16 msg_session(struct tipc_msg *m)
{
return msg_bits(m, 5, 16, 0xffff);
}
static inline void msg_set_session(struct tipc_msg *m, u16 n)
{
msg_set_bits(m, 5, 16, 0xffff, n);
}
static inline u32 msg_probe(struct tipc_msg *m)
{
return msg_bits(m, 5, 0, 1);
}
static inline void msg_set_probe(struct tipc_msg *m, u32 val)
{
msg_set_bits(m, 5, 0, 1, val);
}
static inline char msg_net_plane(struct tipc_msg *m)
{
return msg_bits(m, 5, 1, 7) + 'A';
}
static inline void msg_set_net_plane(struct tipc_msg *m, char n)
{
msg_set_bits(m, 5, 1, 7, (n - 'A'));
}
static inline u32 msg_linkprio(struct tipc_msg *m)
{
return msg_bits(m, 5, 4, 0x1f);
}
static inline void msg_set_linkprio(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 5, 4, 0x1f, n);
}
static inline u32 msg_bearer_id(struct tipc_msg *m)
{
return msg_bits(m, 5, 9, 0x7);
}
static inline void msg_set_bearer_id(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 5, 9, 0x7, n);
}
static inline u32 msg_redundant_link(struct tipc_msg *m)
{
return msg_bits(m, 5, 12, 0x1);
}
static inline void msg_set_redundant_link(struct tipc_msg *m, u32 r)
{
msg_set_bits(m, 5, 12, 0x1, r);
}
static inline char *msg_media_addr(struct tipc_msg *m)
{
return (char *)&m->hdr[TIPC_MEDIA_INFO_OFFSET];
}
/*
* Word 9
*/
static inline u16 msg_msgcnt(struct tipc_msg *m)
{
return msg_bits(m, 9, 16, 0xffff);
}
static inline void msg_set_msgcnt(struct tipc_msg *m, u16 n)
{
msg_set_bits(m, 9, 16, 0xffff, n);
}
static inline u32 msg_bcast_tag(struct tipc_msg *m)
{
return msg_bits(m, 9, 16, 0xffff);
}
static inline void msg_set_bcast_tag(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 16, 0xffff, n);
}
static inline u32 msg_max_pkt(struct tipc_msg *m)
{
return msg_bits(m, 9, 16, 0xffff) * 4;
}
static inline void msg_set_max_pkt(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 16, 0xffff, (n / 4));
}
static inline u32 msg_link_tolerance(struct tipc_msg *m)
{
return msg_bits(m, 9, 0, 0xffff);
}
static inline void msg_set_link_tolerance(struct tipc_msg *m, u32 n)
{
msg_set_bits(m, 9, 0, 0xffff, n);
}
static inline bool msg_peer_link_is_up(struct tipc_msg *m)
tipc: introduce node contact FSM The logics for determining when a node is permitted to establish and maintain contact with its peer node becomes non-trivial in the presence of multiple parallel links that may come and go independently. A known failure scenario is that one endpoint registers both its links to the peer lost, cleans up it binding table, and prepares for a table update once contact is re-establihed, while the other endpoint may see its links reset and re-established one by one, hence seeing no need to re-synchronize the binding table. To avoid this, a node must not allow re-establishing contact until it has confirmation that even the peer has lost both links. Currently, the mechanism for handling this consists of setting and resetting two state flags from different locations in the code. This solution is hard to understand and maintain. A closer analysis even reveals that it is not completely safe. In this commit we do instead introduce an FSM that keeps track of the conditions for when the node can establish and maintain links. It has six states and four events, and is strictly based on explicit knowledge about the own node's and the peer node's contact states. Only events leading to state change are shown as edges in the figure below. +--------------+ | SELF_UP/ | +---------------->| PEER_COMING |-----------------+ SELF_ | +--------------+ |PEER_ ESTBL_ | | |ESTBL_ CONTACT| SELF_LOST_CONTACT | |CONTACT | v | | +--------------+ | | PEER_ | SELF_DOWN/ | SELF_ | | LOST_ +--| PEER_LEAVING |<--+ LOST_ v +-------------+ CONTACT | +--------------+ | CONTACT +-----------+ | SELF_DOWN/ |<----------+ +----------| SELF_UP/ | | PEER_DOWN |<----------+ +----------| PEER_UP | +-------------+ SELF_ | +--------------+ | PEER_ +-----------+ | LOST_ +--| SELF_LEAVING/|<--+ LOST_ A | CONTACT | PEER_DOWN | CONTACT | | +--------------+ | | A | PEER_ | PEER_LOST_CONTACT | |SELF_ ESTBL_ | | |ESTBL_ CONTACT| +--------------+ |CONTACT +---------------->| PEER_UP/ |-----------------+ | SELF_COMING | +--------------+ Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-17 03:54:30 +07:00
{
if (likely(msg_user(m) != LINK_PROTOCOL))
tipc: introduce node contact FSM The logics for determining when a node is permitted to establish and maintain contact with its peer node becomes non-trivial in the presence of multiple parallel links that may come and go independently. A known failure scenario is that one endpoint registers both its links to the peer lost, cleans up it binding table, and prepares for a table update once contact is re-establihed, while the other endpoint may see its links reset and re-established one by one, hence seeing no need to re-synchronize the binding table. To avoid this, a node must not allow re-establishing contact until it has confirmation that even the peer has lost both links. Currently, the mechanism for handling this consists of setting and resetting two state flags from different locations in the code. This solution is hard to understand and maintain. A closer analysis even reveals that it is not completely safe. In this commit we do instead introduce an FSM that keeps track of the conditions for when the node can establish and maintain links. It has six states and four events, and is strictly based on explicit knowledge about the own node's and the peer node's contact states. Only events leading to state change are shown as edges in the figure below. +--------------+ | SELF_UP/ | +---------------->| PEER_COMING |-----------------+ SELF_ | +--------------+ |PEER_ ESTBL_ | | |ESTBL_ CONTACT| SELF_LOST_CONTACT | |CONTACT | v | | +--------------+ | | PEER_ | SELF_DOWN/ | SELF_ | | LOST_ +--| PEER_LEAVING |<--+ LOST_ v +-------------+ CONTACT | +--------------+ | CONTACT +-----------+ | SELF_DOWN/ |<----------+ +----------| SELF_UP/ | | PEER_DOWN |<----------+ +----------| PEER_UP | +-------------+ SELF_ | +--------------+ | PEER_ +-----------+ | LOST_ +--| SELF_LEAVING/|<--+ LOST_ A | CONTACT | PEER_DOWN | CONTACT | | +--------------+ | | A | PEER_ | PEER_LOST_CONTACT | |SELF_ ESTBL_ | | |ESTBL_ CONTACT| +--------------+ |CONTACT +---------------->| PEER_UP/ |-----------------+ | SELF_COMING | +--------------+ Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-17 03:54:30 +07:00
return true;
if (msg_type(m) == STATE_MSG)
return true;
return false;
}
static inline bool msg_peer_node_is_up(struct tipc_msg *m)
{
if (msg_peer_link_is_up(m))
return true;
tipc: introduce node contact FSM The logics for determining when a node is permitted to establish and maintain contact with its peer node becomes non-trivial in the presence of multiple parallel links that may come and go independently. A known failure scenario is that one endpoint registers both its links to the peer lost, cleans up it binding table, and prepares for a table update once contact is re-establihed, while the other endpoint may see its links reset and re-established one by one, hence seeing no need to re-synchronize the binding table. To avoid this, a node must not allow re-establishing contact until it has confirmation that even the peer has lost both links. Currently, the mechanism for handling this consists of setting and resetting two state flags from different locations in the code. This solution is hard to understand and maintain. A closer analysis even reveals that it is not completely safe. In this commit we do instead introduce an FSM that keeps track of the conditions for when the node can establish and maintain links. It has six states and four events, and is strictly based on explicit knowledge about the own node's and the peer node's contact states. Only events leading to state change are shown as edges in the figure below. +--------------+ | SELF_UP/ | +---------------->| PEER_COMING |-----------------+ SELF_ | +--------------+ |PEER_ ESTBL_ | | |ESTBL_ CONTACT| SELF_LOST_CONTACT | |CONTACT | v | | +--------------+ | | PEER_ | SELF_DOWN/ | SELF_ | | LOST_ +--| PEER_LEAVING |<--+ LOST_ v +-------------+ CONTACT | +--------------+ | CONTACT +-----------+ | SELF_DOWN/ |<----------+ +----------| SELF_UP/ | | PEER_DOWN |<----------+ +----------| PEER_UP | +-------------+ SELF_ | +--------------+ | PEER_ +-----------+ | LOST_ +--| SELF_LEAVING/|<--+ LOST_ A | CONTACT | PEER_DOWN | CONTACT | | +--------------+ | | A | PEER_ | PEER_LOST_CONTACT | |SELF_ ESTBL_ | | |ESTBL_ CONTACT| +--------------+ |CONTACT +---------------->| PEER_UP/ |-----------------+ | SELF_COMING | +--------------+ Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-17 03:54:30 +07:00
return msg_redundant_link(m);
}
struct sk_buff *tipc_buf_acquire(u32 size);
bool tipc_msg_validate(struct sk_buff *skb);
bool tipc_msg_reverse(u32 own_addr, struct sk_buff **skb, int err);
2015-02-05 20:36:36 +07:00
void tipc_msg_init(u32 own_addr, struct tipc_msg *m, u32 user, u32 type,
u32 hsize, u32 destnode);
struct sk_buff *tipc_msg_create(uint user, uint type, uint hdr_sz,
uint data_sz, u32 dnode, u32 onode,
u32 dport, u32 oport, int errcode);
int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf);
bool tipc_msg_bundle(struct sk_buff *skb, struct tipc_msg *msg, u32 mtu);
bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg,
u32 mtu, u32 dnode);
tipc: resolve race problem at unicast message reception TIPC handles message cardinality and sequencing at the link layer, before passing messages upwards to the destination sockets. During the upcall from link to socket no locks are held. It is therefore possible, and we see it happen occasionally, that messages arriving in different threads and delivered in sequence still bypass each other before they reach the destination socket. This must not happen, since it violates the sequentiality guarantee. We solve this by adding a new input buffer queue to the link structure. Arriving messages are added safely to the tail of that queue by the link, while the head of the queue is consumed, also safely, by the receiving socket. Sequentiality is secured per socket by only allowing buffers to be dequeued inside the socket lock. Since there may be multiple simultaneous readers of the queue, we use a 'filter' parameter to reduce the risk that they peek the same buffer from the queue, hence also reducing the risk of contention on the receiving socket locks. This solves the sequentiality problem, and seems to cause no measurable performance degradation. A nice side effect of this change is that lock handling in the functions tipc_rcv() and tipc_bcast_rcv() now becomes uniform, something that will enable future simplifications of those functions. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 20:36:41 +07:00
bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos);
2015-02-05 20:36:36 +07:00
int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
int offset, int dsz, int mtu, struct sk_buff_head *list);
bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err);
bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq);
void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
struct sk_buff *skb);
static inline u16 buf_seqno(struct sk_buff *skb)
{
return msg_seqno(buf_msg(skb));
}
/* tipc_skb_peek(): peek and reserve first buffer in list
* @list: list to be peeked in
* Returns pointer to first buffer in list, if any
*/
static inline struct sk_buff *tipc_skb_peek(struct sk_buff_head *list,
spinlock_t *lock)
{
struct sk_buff *skb;
spin_lock_bh(lock);
skb = skb_peek(list);
if (skb)
skb_get(skb);
spin_unlock_bh(lock);
return skb;
}
tipc: resolve race problem at unicast message reception TIPC handles message cardinality and sequencing at the link layer, before passing messages upwards to the destination sockets. During the upcall from link to socket no locks are held. It is therefore possible, and we see it happen occasionally, that messages arriving in different threads and delivered in sequence still bypass each other before they reach the destination socket. This must not happen, since it violates the sequentiality guarantee. We solve this by adding a new input buffer queue to the link structure. Arriving messages are added safely to the tail of that queue by the link, while the head of the queue is consumed, also safely, by the receiving socket. Sequentiality is secured per socket by only allowing buffers to be dequeued inside the socket lock. Since there may be multiple simultaneous readers of the queue, we use a 'filter' parameter to reduce the risk that they peek the same buffer from the queue, hence also reducing the risk of contention on the receiving socket locks. This solves the sequentiality problem, and seems to cause no measurable performance degradation. A nice side effect of this change is that lock handling in the functions tipc_rcv() and tipc_bcast_rcv() now becomes uniform, something that will enable future simplifications of those functions. Reviewed-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 20:36:41 +07:00
/* tipc_skb_peek_port(): find a destination port, ignoring all destinations
* up to and including 'filter'.
* Note: ignoring previously tried destinations minimizes the risk of
* contention on the socket lock
* @list: list to be peeked in
* @filter: last destination to be ignored from search
* Returns a destination port number, of applicable.
*/
static inline u32 tipc_skb_peek_port(struct sk_buff_head *list, u32 filter)
{
struct sk_buff *skb;
u32 dport = 0;
bool ignore = true;
spin_lock_bh(&list->lock);
skb_queue_walk(list, skb) {
dport = msg_destport(buf_msg(skb));
if (!filter || skb_queue_is_last(list, skb))
break;
if (dport == filter)
ignore = false;
else if (!ignore)
break;
}
spin_unlock_bh(&list->lock);
return dport;
}
/* tipc_skb_dequeue(): unlink first buffer with dest 'dport' from list
* @list: list to be unlinked from
* @dport: selection criteria for buffer to unlink
*/
static inline struct sk_buff *tipc_skb_dequeue(struct sk_buff_head *list,
u32 dport)
{
struct sk_buff *_skb, *tmp, *skb = NULL;
spin_lock_bh(&list->lock);
skb_queue_walk_safe(list, _skb, tmp) {
if (msg_destport(buf_msg(_skb)) == dport) {
__skb_unlink(_skb, list);
skb = _skb;
break;
}
}
spin_unlock_bh(&list->lock);
return skb;
}
/* tipc_skb_queue_splice_tail - append an skb list to lock protected list
* @list: the new list to append. Not lock protected
* @head: target list. Lock protected.
*/
static inline void tipc_skb_queue_splice_tail(struct sk_buff_head *list,
struct sk_buff_head *head)
{
spin_lock_bh(&head->lock);
skb_queue_splice_tail(list, head);
spin_unlock_bh(&head->lock);
}
/* tipc_skb_queue_splice_tail_init - merge two lock protected skb lists
* @list: the new list to add. Lock protected. Will be reinitialized
* @head: target list. Lock protected.
*/
static inline void tipc_skb_queue_splice_tail_init(struct sk_buff_head *list,
struct sk_buff_head *head)
{
struct sk_buff_head tmp;
__skb_queue_head_init(&tmp);
spin_lock_bh(&list->lock);
skb_queue_splice_tail_init(list, &tmp);
spin_unlock_bh(&list->lock);
tipc_skb_queue_splice_tail(&tmp, head);
}
#endif