Reduces the maximum size of messages sent during the initial exchange
of name table information between two nodes to be no larger than the
MTU of the first link established between the nodes. This ensures that
messages will never need to be fragmented, which would add unnecessary
overhead to the name table synchronization mechanism.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reduces the number of bearers a node can support to 2, which can use
identical or non-identical media. This change won't impact users,
since they are currently limited to a maximum of 2 Ethernet bearers,
and will save memory by eliminating a number of unused entries in
TIPC's media and bearer arrays.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Removes obsolete code that searches for an Ethernet bearer structure entry
to use for a newly enabled bearer, since this search is now performed
at the start of the enabling algorithm.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensures that the device list lock is held while trying to locate
the Ethernet device used by a newly enabled bearer, so that the
addition or removal of a device does not cause problems.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Enhances TIPC to ensure that a node that loses contact with a
neighboring node does not allow contact to be re-established until
it sees that its peer has also recognized the loss of contact.
Previously, nodes that were connected by two or more links could
encounter a situation in which node A would lose contact with node B
on all of its links, purge its name table of names published by B,
and then fail to repopulate those names once contact with B was restored.
This would happen because B was able to re-establish one or more links
so quickly that it never reached a point where it had no links to A --
meaning that B never saw a loss of contact with A, and consequently
didn't re-publish its names to A.
This problem is now prevented by enhancing the cleanup done by TIPC
following a loss of contact with a neighboring node to ensure that
node A ignores all messages sent by B until it receives a LINK_PROTOCOL
message that indicates B has lost contact with A, thereby preventing
the (re)establishment of links between the nodes. The loss of contact
is recognized when a RESET or ACTIVATE message is received that has
a "redundant link exists" field of 0, indicating that B's sending link
endpoint is in a reset state and that B has no other working links.
Additionally, TIPC now suppresses the sending of (most) link protocol
messages to a neighboring node while it is cleaning up after an earlier
loss of contact with that node. This stops the peer node from prematurely
activating its link endpoint, which would prevent TIPC from later
activating its own end. TIPC still allows outgoing RESET messages to
occur during cleanup, to avoid problems if its own node recognizes
the loss of contact first and tries to notify the peer of the situation.
Finally, TIPC now recognizes an impending loss of contact with a peer node
as soon as it receives a RESET message on a working link that is the
peer's only link to the node, and ensures that the link protocol
suppression mentioned above goes into effect right away -- that is,
even before its own link endpoints have failed. This is necessary to
ensure correct operation when there are redundant links between the nodes,
since otherwise TIPC would send an ACTIVATE message upon receiving a RESET
on its first link and only begin suppressing when a RESET on its second
link was received, instead of initiating suppression with the first RESET
message as it needs to.
Note: The reworked cleanup code also eliminates a check that prevented
a link endpoint's discovery object from responding to incoming messages
while stale name table entries are being purged. This check is now
unnecessary and would have slowed down re-establishment of communication
between the nodes in some situations.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies code that disables a bearer to ensure that all of its links
are deleted, not just its uncongested links. Similarly, modifies code
that blocks a bearer to ensure that all of its links are reset, not
just its uncongested links.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Saves a socket's TIPC_CONN_TIMEOUT socket option value in its original
form (milliseconds), rather than jiffies. This ensures that the exact
value set using setsockopt() is always returned by getsockopt(), without
being subject to rounding issues introduced by a ms->jiffies->ms
conversion sequence.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates code in tipc_send_buf_fast() that handles messages
sent to a destination on the current node, since the only caller
of the routine only passes in messages destined for other nodes.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates obsolete code that handles broadcast bearer congestion when
the broadast link sends a NACK message, since the broadcast pseudo-bearer
never becomes blocked.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies TIPC's incoming broadcast packet handler to discard messages
that cannot legally be sent over the broadcast link, including:
- broadcast protocol messages that do no contain state information
- payload messages that are not named multicast messages
- any other form of message except for bundled messages, fragmented
messages, and name distribution messages.
These checks are needed to prevent TIPC from handing an unexpected
message to a routine that isn't prepared to handle it, which could
lead to incorrect processing (up to and including invalid memory
references caused by attempts to access message fields that aren't
present in the message).
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies TIPC's incoming broadcast packet handler so that it no longer
pre-reads information about the deferred packet queue, since the cached
value is unreliable once the associated node lock has been released.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies TIPC's incoming broadcast packet handler to ensure that the
node lock associated with the sender of the packet is held whenever
node-related data structure fields are accessed. The routine is also
restructured with a single exit point, making it easier to ensure
the node lock is properly released and the incoming packet is properly
disposed of.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensure that broadcast link messages that have not been acknowledged
by a newly failed node do not get an implied acknowledgement until the
failed node is removed from the broadcast link's map of reachable nodes.
Previously, a race condition allowed a new broadcast link message to be
sent after the implicit acknowledgement processing was completed, but
before the map of reachable nodes was updated, resulting in the message
having an expected acknowledgement count that required the failed node
to explicitly acknowledge the message. Since this would never occur
the new message would remain in the broadcast link's transmit queue
forever, eventually causing the link to become congested and "stall".
Delaying the implicit acknowledgement processing until after the update
of the map of reachable nodes eliminates this race condition and prevents
stalling.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Enhances cleanup of broadcast link-related information when contact
with a node is lost.
1) All broadcast link-related cleanup now occurs only if the lost node
was capable of communicating over the broadcast link.
2) Following cleanup, the lost node is marked as no longer supporting
the broadcast link, ensuring that any remaining broadcast messages
received from that node prior to the re-establishment of a normal
communication link are ignored.
Thanks to Surya [Suryanarayana.Garlapati@emerson.com] for contributing
a prototype version of this patch.
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>
Updates the comments in the broadcast bearer send routine to more
accurately describe the processing done by the routine. Also replaces
the improper use of a TIPC payload message error status symbol (in a place
that has nothing to do with such errors) with its numeric equivalent.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Updates TIPC's broadcast link in a couple of places that were missed
during the transition from its former name ("multicast-link") to its
current name ("broadcast-link"). These changes are essentially cosmetic
and do not affect the overall operation of TIPC.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensure TIPC ignores an out-dated link reset message whose session
number predates the current session number. (Previously, TIPC only
ignored an out-date reset message whose session number was equal
to the current link session number.)
Out-dated link reset messages should not occur under normal circumstances;
however, they can be generated if a link endpoint is unable to send a
link reset message right away and queues it for later delivery, but the
queued message is not sent until after the link is established.
Thanks to Laser [gotolaser@gmail.com] for diagnosing the problem and
contributing a prototype patch.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Initializes the peer session number field of a newly created link
endpoint to an invalid value. This eliminates the remote possibility
that it will accidentally match the session number used by the peer
the first time the link is activated, and cause the link to ignore
a valid RESET message.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Sets the peer interface portion of the name of a newly created link
endpoint to "unknown". This ensures that state and statistics information
can be properly displayed during the time between the link endpoint's
creation and the time handshaking with its peer is completed.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Removes a test that ensures unicast link endpoints discard an incoming
message if it will not be consumed by the node itself and cannot be
forwarded to another node, since the preceding test already ensures that
the message is destined for this node and single-cluster TIPC no longer
performs message forwarding.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates code that increments and validates the re-route count field
of payload messages, since the elimination of multi-cluster support
means that it is no longer necessary for TIPC to forward incoming messages
to another node. (The obsolete code was incorrect anyway, since it
incorrectly incremented the re-route count field of messages that
originated on the node that forwarded the message.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Simplifies the creation of connection protocol messages by eliminating
the passing of information that is no longer required, is constant,
or is contained within the port structure that is issuing the message.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies the logic that creates a connection termination payload
message so that it no longer (mis)uses a routine that creates a
connection protocol message. The revised code is now more easily
understood, and avoids setting several fields that are either not
present in payload messages or were being set more than once.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Restructures the logic used in tipc_port_recv_proto_msg() to ensure
that incoming connection protocol messages are handled properly. The
routine now uses a two-stage process that first ensures the message
applies on an existing connection and then processes the request.
This corrects a loophole that allowed a connection probe request to
be processed if it was sent to an unconnected port that had no names
bound to it.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Speeds up the creation of the FIN message that terminates a TIPC
connection. The typical peer termination message is now created by
duplicating the terminating port's standard payload message header
and adjusting the message size, importance, and error code fields,
rather than building all fields of the message from scratch. A FIN
message that is directed to the port itself is created the same way.
but also requires swapping the origin and destination address fields.
In addition to reducing the work required to create FIN messages,
these changes eliminate several instances of duplicated code,
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Performs cosmetic cleanup of the symbolic names used to specify TIPC
payload message header sizes. The revised names now more accurately
reflect the payload messages in which they can appear. In addition,
several places where these payload message symbol names were being used
to create non-payload messages have been updated to use the proper
internal message symbolic name.
No functional changes are introduced by this rework.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of code that allows tipc_msg_init() to create a short
payload message header. This optimization is possible because
there are no longer any callers who require this capability.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates a pair of #include statements for files that are brought in
automatically by including core.h.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of counter that records the number of times a bearer has
resumed after congestion or blocking, since the value is never
referenced anywhere.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fixes a minor error in the title of one of the message size profiling
values printed as part of TIPC's link statistics.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of a pair of checks to see if a name sequence entry in
TIPC's name table has an empty zone list. These checks are pointless
since the zone list can never be empty (i.e. as soon as the list
becomes empty the associated name sequence entry is deleted).
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies the main circular linked lists of publications used in TIPC's
name table to use the standard kernel linked list type. This change
simplifies the deletion of an existing publication by eliminating
the need to search up to three lists to locate the publication.
The use of standard list routines also helps improve the readability
of the name table code by make it clearer what each list operation
being performed is actually doing.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies the name table array structure that contains the name
sequence instances for a given name type so that the publication
lists associated with a given instance are stored in a dynamically
allocated structure, rather than being embedded within the array
entry itself. This change is being done for several reasons:
1) It reduces the amount of data that needs to be copied whenever
a given array is expanded or contracted to accommodate the first
publication of a new name sequence or the removal of the last
publication of an existing name sequence.
2) It reduces the amount of memory associated with array entries that
are currently unused.
3) It facilitates the upcoming conversion of the publication lists
from TIPC-specific circular lists to standard kernel lists. (Standard
lists cannot be used with the former array structure because the
relocation of array entries during array expansion and contraction
would corrupt the lists.)
Note that, aside from introducing a small amount of code to dynamically
allocate and free the structure that now holds publication list info,
this change is largely a simple renaming exercise that replaces
references to "sseq->LIST" with "sseq->info->LIST" (or "info->LIST").
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of unnecessary masking in two routines that set TIPC message
header fields. (The msg_set_bits() routine already takes care of
masking the new value to the correct size.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of a pair of routines that provide support for temporarily
caching the destination node for a message in the associated message
buffer's application handle, since this capability is no longer used.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Optimizes the creation of a returned payload message by duplicating
the original message and then updating the small number of fields
that need to be adjusted, rather than building the new message header
from scratch. In addition, certain operations that are not always
required are relocated so that they are only done if needed.
These optimizations also have the effect of addressing other issues
that were present previously:
1) Fixes a bug that caused the socket send routines to return the
size of the returned message, rather than the size of the sent
message, when a returnable payload message was sent to a non-existent
destination port.
2) The message header of the returned message now matches that of
the original message more closely. The header is now always the same
size as the original header, and some message header fields that
weren't being initialized in the returned message header are now
populated correctly -- namely the "d" and "s" bits, and the upper
bound of a multicast name instance (where present).
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reduces the work involved in transmitting a returned payload message
by doing only the work necessary to route such a message directly to
the specified destination port, rather than invoking the code used
to route an arbitrary message to an arbitrary destination.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Introduces an internal sanity check to ensure that the only undeliverable
messages TIPC attempts to return to their origin are application payload
messages.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies the routine that handles the rejection of payload messages
so that it has a single exit point that frees up the rejected message,
thereby eliminating some duplicated code.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Eliminates a TIPC-specific assert() macro that is no longer used.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies the existing broadcast link sanity check that detects an
attempt to send a message off-node when there are no available
destinations so that it no longer causes a kernel panic; instead,
the check now issues a warning and stack trace and then returns
without sending the message anywhere.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Revises the algorithm governing the sending of link request messages
to take into account the number of nodes each bearer is currently in
contact with, and to ensure more rapid rediscovery of neighboring nodes
if a bearer fails and then recovers.
The discovery object now sends requests at least once a second if it
is not in contact with any other nodes, and at least once a minute if
it has at least one neighbor; if contact with the only neighbor is
lost, the object immediately reverts to its initial rapid-fire search
timing to accelerate the rediscovery process.
In addition, the discovery object now stops issuing link request
messages if it is in contact with the only neighboring node it is
configured to communicate with, since further searching is unnecessary.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Augments TIPC's discovery object to track the number of neighboring nodes
having an active link to the associated bearer.
This means tipc_disc_update_link_req() becomes either one of:
tipc_disc_add_dest()
or:
tipc_disc_remove_dest()
depending on the code flow direction of things.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Augments TIPC's discovery object to send its initial neighbor discovery
request message as soon as the associated bearer is created, rather than
waiting for its first periodic timeout to occur, thereby speeding up the
discovery process. Also adds a check to suppress the initial request or
subsequent requests if the bearer is blocked at the time the request is
scheduled for transmission.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies bearer creation and deletion code to improve handling of
scenarios when a neighbor discovery object cannot be created. The
creation routine now aborts the creation of a bearer if its discovery
object cannot be created, and deletes the newly created bearer, rather
than failing quietly and leaving an unusable bearer hanging around.
Since the exit via the goto label really isn't a definitive failure
in all cases, relabel it appropriately.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Create a helper routine to enqueue a chain of sk_buffs to a link's
transmit queue. It improves readability and the new function is
anticipated to be used more than just once in the future as well.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Rework TIPC's message sending routines to take advantage of the total
amount of data value passed to it by the kernel socket infrastructure.
This change eliminates the need for TIPC to compute the size of outgoing
messages itself, as well as the check for an oversize message in
tipc_msg_build(). In addition, this change warrants an explanation:
- res = send_packet(NULL, sock, &my_msg, 0);
+ res = send_packet(NULL, sock, &my_msg, bytes_to_send);
Previously, the final argument to send_packet() was ignored (since the
amount of data being sent was recalculated by a lower-level routine)
and we could just pass in a dummy value (0). Now that the
recalculation is being eliminated, the argument value being passed to
send_packet() is significant and we have to supply the actual amount
of data we want to send.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Adds checks to TIPC's socket send routines to promptly detect and
abort attempts to send more than 66,000 bytes in a single TIPC
message or more than 2**31-1 bytes in a single TIPC byte stream request.
In addition, this ensures that the number of iovecs in a send request
does not exceed the limits of a standard integer variable.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>