Completely redesigns broadcast link ACK and NACK mechanisms to prevent
spurious retransmit requests in dual LAN networks, and to prevent the
broadcast link from stalling due to the failure of a receiving node to
acknowledge receiving a broadcast message or request its retransmission.
Note: These changes only impact the timing of when ACK and NACK messages
are sent, and not the basic broadcast link protocol itself, so inter-
operability with nodes using the "classic" algorithms is maintained.
The revised algorithms are as follows:
1) An explicit ACK message is still sent after receiving 16 in-sequence
messages, and implicit ACK information continues to be carried in other
unicast link message headers (including link state messages). However,
the timing of explicit ACKs is now based on the receiving node's absolute
network address rather than its relative network address to ensure that
the failure of another node does not delay the ACK beyond its 16 message
target.
2) A NACK message is now typically sent only when a message gap persists
for two consecutive incoming link state messages; this ensures that a
suspected gap is not confirmed until both LANs in a dual LAN network have
had an opportunity to deliver the message, thereby preventing spurious NACKs.
A NACK message can also be generated by the arrival of a single link state
message, if the deferred queue is so big that the current message gap
cannot be the result of "normal" mis-ordering due to the use of dual LANs
(or one LAN using a bonded interface). Since link state messages typically
arrive at different nodes at different times the problem of multiple nodes
issuing identical NACKs simultaneously is inherently avoided.
3) Nodes continue to "peek" at NACK messages sent by other nodes. If
another node requests retransmission of a message gap suspected (but not
yet confirmed) by the peeking node, the peeking node forgets about the
gap and does not generate a duplicate retransmit request. (If the peeking
node subsequently fails to receive the lost message, later link state
messages will cause it to rediscover and confirm the gap and send another
NACK.)
4) Message gap "equality" is now determined by the start of the gap only.
This is sufficient to deal with the most common cases of message loss,
and eliminates the need for complex end of gap computations.
5) A peeking node no longer tries to determine whether it should send a
complementary NACK, since the most common cases of message loss don't
require it to be sent. Consequently, the node no longer examines the
"broadcast tag" field of a NACK message when peeking.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Make this rename so that it is consistent with the majority
of the other tipc structs and to assist in removing any
ambiguity with other similar names in other subsystems.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fixes oversight that allowed broadcast link node map to be updated without
first taking the broadcast link spinlock that protects the map. As part
of this fix the node map has been incorporated into the broadcast link
structure to make the need for such protection more evident.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Creates global variables to hold the broadcast link's pseudo-bearer and
pseudo-link structures, rather than allocating them dynamically. There
is only a single instance of each structure, and changing over to static
allocation allows elimination of code to handle the cases where dynamic
allocation was unsuccessful.
The memset in the teardown code may look like they aren't used, but
the same teardown code is run when there is a non-fatal error at
init-time, so that stale data isn't present when the user fixes the
cause of the soft error.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates code associated with the sending of unsent broadcast link
traffic when the broadcast pseudo-bearer becomes unblocked following a
temporary congestion situation. This code is non-executable because the
broadcast pseudo-bearer never becomes blocked [see tipc_bcbearer_send()].
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Allows the broadcast link to track the node that is requesting a retransmit
in a new field dedicated to that purpose. This replaces the existing
mechanism that (ab)uses an existing node structure linked list field to do
the tracking.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates routines, data structures, and files that were intended
to allow TIPC to support a network containing multiple clusters.
Currently, TIPC supports only networks consisting of a single cluster
within a single zone, so this code is unnecessary.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do some cleanups of TIPC based on make namespacecheck
1. Don't export unused symbols
2. Eliminate dead code
3. Make functions and variables local
4. Rename buf_acquire to tipc_buf_acquire since it is used in several files
Compile tested only.
This make break out of tree kernel modules that depend on TIPC routines.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Converts port list inline routines that are more than one line into
standard functions, thereby eliminating a significant amount of
repeated code.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Converts nmap inline routines that are more than one line into standard
functions, thereby eliminating a significant amount of repeated code.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These functions have enough code in them such that they
seem like sensible targets for un-inlining. Prior to doing
that, this adds the tipc_ prefix to the functions, so that
in the event of a panic dump or similar, the subsystem from
which the functions come from is immediately clear.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix warnings from current gcc about using non-const strings as printf
args in TIPC. Compile tested only (not a TIPC user).
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ARRAY_SIZE is more concise to use when the size of an array is divided by
the size of its type or the size of its first element.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@i@
@@
#include <linux/kernel.h>
@depends on i using "paren.iso"@
type T;
T[] E;
@@
- (sizeof(E)/sizeof(T))
+ ARRAY_SIZE(E)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrew Morton reported a build failure on sparc32, because TIPC
uses names like "struct node" and there is a like named data
structure defined in linux/node.h
This just regexp replaces "struct node*" to "struct tipc_node*"
to avoid this and any future similar problems.
Signed-off-by: David S. Miller <davem@davemloft.net>
All these static inlines are unused:
in_own_zone 1 (net/tipc/addr.h)
msg_dataoctet 1 (net/tipc/msg.h)
msg_direct 1 (include/net/tipc/tipc_msg.h)
msg_options 1 (include/net/tipc/tipc_msg.h)
tipc_nmap_get 1 (net/tipc/bcast.h)
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Per Liden <per.liden@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The license header in each file now more clearly state that this
code is licensed under a dual BSD/GPL. Before this was only
evident if you looked at the MODULE_LICENSE line in core.c.
Signed-off-by: Per Liden <per.liden@nospam.ericsson.com>
TIPC (Transparent Inter Process Communication) is a protocol designed for
intra cluster communication. For more information see
http://tipc.sourceforge.net
Signed-off-by: Per Liden <per.liden@nospam.ericsson.com>
Allan Stephens