1. 15 8月, 2012 15 次提交
  2. 23 7月, 2012 1 次提交
    • N
      sctp: Implement quick failover draft from tsvwg · 5aa93bcf
      Neil Horman 提交于
      I've seen several attempts recently made to do quick failover of sctp transports
      by reducing various retransmit timers and counters.  While its possible to
      implement a faster failover on multihomed sctp associations, its not
      particularly robust, in that it can lead to unneeded retransmits, as well as
      false connection failures due to intermittent latency on a network.
      
      Instead, lets implement the new ietf quick failover draft found here:
      http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05
      
      This will let the sctp stack identify transports that have had a small number of
      errors, and avoid using them quickly until their reliability can be
      re-established.  I've tested this out on two virt guests connected via multiple
      isolated virt networks and believe its in compliance with the above draft and
      works well.
      Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
      CC: Vlad Yasevich <vyasevich@gmail.com>
      CC: Sridhar Samudrala <sri@us.ibm.com>
      CC: "David S. Miller" <davem@davemloft.net>
      CC: linux-sctp@vger.kernel.org
      CC: joe@perches.com
      Acked-by: NVlad Yasevich <vyasevich@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5aa93bcf
  3. 16 7月, 2012 1 次提交
  4. 12 7月, 2012 1 次提交
  5. 01 7月, 2012 1 次提交
    • N
      sctp: be more restrictive in transport selection on bundled sacks · 4244854d
      Neil Horman 提交于
      It was noticed recently that when we send data on a transport, its possible that
      we might bundle a sack that arrived on a different transport.  While this isn't
      a major problem, it does go against the SHOULD requirement in section 6.4 of RFC
      2960:
      
       An endpoint SHOULD transmit reply chunks (e.g., SACK, HEARTBEAT ACK,
         etc.) to the same destination transport address from which it
         received the DATA or control chunk to which it is replying.  This
         rule should also be followed if the endpoint is bundling DATA chunks
         together with the reply chunk.
      
      This patch seeks to correct that.  It restricts the bundling of sack operations
      to only those transports which have moved the ctsn of the association forward
      since the last sack.  By doing this we guarantee that we only bundle outbound
      saks on a transport that has received a chunk since the last sack.  This brings
      us into stricter compliance with the RFC.
      
      Vlad had initially suggested that we strictly allow only sack bundling on the
      transport that last moved the ctsn forward.  While this makes sense, I was
      concerned that doing so prevented us from bundling in the case where we had
      received chunks that moved the ctsn on multiple transports.  In those cases, the
      RFC allows us to select any of the transports having received chunks to bundle
      the sack on.  so I've modified the approach to allow for that, by adding a state
      variable to each transport that tracks weather it has moved the ctsn since the
      last sack.  This I think keeps our behavior (and performance), close enough to
      our current profile that I think we can do this without a sysctl knob to
      enable/disable it.
      Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
      CC: Vlad Yaseivch <vyasevich@gmail.com>
      CC: David S. Miller <davem@davemloft.net>
      CC: linux-sctp@vger.kernel.org
      Reported-by: NMichele Baldessari <michele@redhat.com>
      Reported-by: Nsorin serban <sserban@redhat.com>
      Acked-by: NVlad Yasevich <vyasevich@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4244854d
  6. 11 5月, 2012 1 次提交
  7. 16 4月, 2012 1 次提交
  8. 09 3月, 2012 1 次提交
  9. 20 12月, 2011 2 次提交
  10. 12 12月, 2011 1 次提交
  11. 09 11月, 2011 1 次提交
  12. 17 9月, 2011 1 次提交
    • M
      sctp: deal with multiple COOKIE_ECHO chunks · d5ccd496
      Max Matveev 提交于
      Attempt to reduce the number of IP packets emitted in response to single
      SCTP packet (2e3216cd) introduced a complication - if a packet contains
      two COOKIE_ECHO chunks and nothing else then SCTP state machine corks the
      socket while processing first COOKIE_ECHO and then loses the association
      and forgets to uncork the socket. To deal with the issue add new SCTP
      command which can be used to set association explictly. Use this new
      command when processing second COOKIE_ECHO chunk to restore the context
      for SCTP state machine.
      Signed-off-by: NMax Matveev <makc@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d5ccd496
  13. 25 8月, 2011 1 次提交
  14. 27 7月, 2011 1 次提交
  15. 09 7月, 2011 1 次提交
  16. 08 7月, 2011 1 次提交
    • T
      sctp: Enforce retransmission limit during shutdown · f8d96052
      Thomas Graf 提交于
      When initiating a graceful shutdown while having data chunks
      on the retransmission queue with a peer which is in zero
      window mode the shutdown is never completed because the
      retransmission error count is reset periodically by the
      following two rules:
      
       - Do not timeout association while doing zero window probe.
       - Reset overall error count when a heartbeat request has
         been acknowledged.
      
      The graceful shutdown will wait for all outstanding TSN to
      be acknowledged before sending the SHUTDOWN request. This
      never happens due to the peer's zero window not acknowledging
      the continuously retransmitted data chunks. Although the
      error counter is incremented for each failed retransmission,
      the receiving of the SACK announcing the zero window clears
      the error count again immediately. Also heartbeat requests
      continue to be sent periodically. The peer acknowledges these
      requests causing the error counter to be reset as well.
      
      This patch changes behaviour to only reset the overall error
      counter for the above rules while not in shutdown. After
      reaching the maximum number of retransmission attempts, the
      T5 shutdown guard timer is scheduled to give the receiver
      some additional time to recover. The timer is stopped as soon
      as the receiver acknowledges any data.
      
      The issue can be easily reproduced by establishing a sctp
      association over the loopback device, constantly queueing
      data at the sender while not reading any at the receiver.
      Wait for the window to reach zero, then initiate a shutdown
      by killing both processes simultaneously. The association
      will never be freed and the chunks on the retransmission
      queue will be retransmitted indefinitely.
      Signed-off-by: NThomas Graf <tgraf@infradead.org>
      Acked-by: NVlad Yasevich <vladislav.yasevich@hp.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f8d96052
  17. 06 6月, 2011 1 次提交
  18. 02 6月, 2011 4 次提交
  19. 01 6月, 2011 1 次提交
  20. 09 5月, 2011 1 次提交
  21. 08 5月, 2011 1 次提交
  22. 28 4月, 2011 1 次提交