1. 29 4月, 2017 1 次提交
  2. 08 4月, 2017 1 次提交
  3. 18 2月, 2017 1 次提交
  4. 08 2月, 2017 1 次提交
  5. 04 2月, 2017 2 次提交
  6. 02 2月, 2017 1 次提交
  7. 30 1月, 2017 1 次提交
  8. 26 1月, 2017 1 次提交
  9. 14 1月, 2017 3 次提交
    • Y
      tcp: remove early retransmit · bec41a11
      Yuchung Cheng 提交于
      This patch removes the support of RFC5827 early retransmit (i.e.,
      fast recovery on small inflight with <3 dupacks) because it is
      subsumed by the new RACK loss detection. More specifically when
      RACK receives DUPACKs, it'll arm a reordering timer to start fast
      recovery after a quarter of (min)RTT, hence it covers the early
      retransmit except RACK does not limit itself to specific inflight
      or dupack numbers.
      Signed-off-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NNeal Cardwell <ncardwell@google.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bec41a11
    • Y
      tcp: remove forward retransmit feature · 840a3cbe
      Yuchung Cheng 提交于
      Forward retransmit is an esoteric feature in RFC3517 (condition(3)
      in the NextSeg()). Basically if a packet is not considered lost by
      the current criteria (# of dupacks etc), but the congestion window
      has room for more packets, then retransmit this packet.
      
      However it actually conflicts with the rest of recovery design. For
      example, when reordering is detected we want to be conservative
      in retransmitting packets but forward-retransmit feature would
      break that to force more retransmission. Also the implementation is
      fairly complicated inside the retransmission logic inducing extra
      iterations in the write queue. With RACK losses are being detected
      timely and this heuristic is no longer necessary. There this patch
      removes the feature.
      Signed-off-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NNeal Cardwell <ncardwell@google.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      840a3cbe
    • Y
      tcp: add reordering timer in RACK loss detection · 57dde7f7
      Yuchung Cheng 提交于
      This patch makes RACK install a reordering timer when it suspects
      some packets might be lost, but wants to delay the decision
      a little bit to accomodate reordering.
      
      It does not create a new timer but instead repurposes the existing
      RTO timer, because both are meant to retransmit packets.
      Specifically it arms a timer ICSK_TIME_REO_TIMEOUT when
      the RACK timing check fails. The wait time is set to
      
        RACK.RTT + RACK.reo_wnd - (NOW - Packet.xmit_time) + fudge
      
      This translates to expecting a packet (Packet) should take
      (RACK.RTT + RACK.reo_wnd + fudge) to deliver after it was sent.
      
      When there are multiple packets that need a timer, we use one timer
      with the maximum timeout. Therefore the timer conservatively uses
      the maximum window to expire N packets by one timeout, instead of
      N timeouts to expire N packets sent at different times.
      
      The fudge factor is 2 jiffies to ensure when the timer fires, all
      the suspected packets would exceed the deadline and be marked lost
      by tcp_rack_detect_loss(). It has to be at least 1 jiffy because the
      clock may tick between calling icsk_reset_xmit_timer(timeout) and
      actually hang the timer. The next jiffy is to lower-bound the timeout
      to 2 jiffies when reo_wnd is < 1ms.
      
      When the reordering timer fires (tcp_rack_reo_timeout): If we aren't
      in Recovery we'll enter fast recovery and force fast retransmit.
      This is very similar to the early retransmit (RFC5827) except RACK
      is not constrained to only enter recovery for small outstanding
      flights.
      Signed-off-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NNeal Cardwell <ncardwell@google.com>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      57dde7f7
  10. 26 12月, 2016 1 次提交
    • T
      ktime: Get rid of the union · 2456e855
      Thomas Gleixner 提交于
      ktime is a union because the initial implementation stored the time in
      scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
      variant for 32bit machines. The Y2038 cleanup removed the timespec variant
      and switched everything to scalar nanoseconds. The union remained, but
      become completely pointless.
      
      Get rid of the union and just keep ktime_t as simple typedef of type s64.
      
      The conversion was done with coccinelle and some manual mopping up.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      2456e855
  11. 22 12月, 2016 1 次提交
  12. 06 12月, 2016 7 次提交
  13. 03 12月, 2016 1 次提交
    • F
      tcp: randomize tcp timestamp offsets for each connection · 95a22cae
      Florian Westphal 提交于
      jiffies based timestamps allow for easy inference of number of devices
      behind NAT translators and also makes tracking of hosts simpler.
      
      commit ceaa1fef ("tcp: adding a per-socket timestamp offset")
      added the main infrastructure that is needed for per-connection ts
      randomization, in particular writing/reading the on-wire tcp header
      format takes the offset into account so rest of stack can use normal
      tcp_time_stamp (jiffies).
      
      So only two items are left:
       - add a tsoffset for request sockets
       - extend the tcp isn generator to also return another 32bit number
         in addition to the ISN.
      
      Re-use of ISN generator also means timestamps are still monotonically
      increasing for same connection quadruple, i.e. PAWS will still work.
      
      Includes fixes from Eric Dumazet.
      Signed-off-by: NFlorian Westphal <fw@strlen.de>
      Acked-by: NEric Dumazet <edumazet@google.com>
      Acked-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      95a22cae
  14. 30 11月, 2016 4 次提交
  15. 25 11月, 2016 1 次提交
    • E
      tcp: enhance tcp_collapse_retrans() with skb_shift() · f8071cde
      Eric Dumazet 提交于
      In commit 2331ccc5 ("tcp: enhance tcp collapsing"),
      we made a first step allowing copying right skb to left skb head.
      
      Since all skbs in socket write queue are headless (but possibly the very
      first one), this strategy often does not work.
      
      This patch extends tcp_collapse_retrans() to perform frag shifting,
      thanks to skb_shift() helper.
      
      This helper needs to not BUG on non headless skbs, as callers are ok
      with that.
      
      Tested:
      
      Following packetdrill test now passes :
      
      0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
         +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
         +0 bind(3, ..., ...) = 0
         +0 listen(3, 1) = 0
      
         +0 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 8>
         +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
      +.100 < . 1:1(0) ack 1 win 257
         +0 accept(3, ..., ...) = 4
      
         +0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0
         +0 write(4, ..., 200) = 200
         +0 > P. 1:201(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 201:401(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 401:601(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 601:801(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 801:1001(200) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1001:1101(100) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1101:1201(100) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1201:1301(100) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1301:1401(100) ack 1
      
      +.099 < . 1:1(0) ack 201 win 257
      +.001 < . 1:1(0) ack 201 win 257 <nop,nop,sack 1001:1401>
         +0 > P. 201:1001(800) ack 1
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Neal Cardwell <ncardwell@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Acked-by: NYuchung Cheng <ycheng@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f8071cde
  16. 03 11月, 2016 1 次提交
    • E
      tcp: enhance tcp collapsing · 2331ccc5
      Eric Dumazet 提交于
      As Ilya Lesokhin suggested, we can collapse two skbs at retransmit
      time even if the skb at the right has fragments.
      
      We simply have to use more generic skb_copy_bits() instead of
      skb_copy_from_linear_data() in tcp_collapse_retrans()
      
      Also need to guard this skb_copy_bits() in case there is nothing to
      copy, otherwise skb_put() could panic if left skb has frags.
      
      Tested:
      
      Used following packetdrill test
      
      // Establish a connection.
      0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
         +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
         +0 bind(3, ..., ...) = 0
         +0 listen(3, 1) = 0
      
         +0 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 8>
         +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
      +.100 < . 1:1(0) ack 1 win 257
         +0 accept(3, ..., ...) = 4
      
         +0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0
         +0 write(4, ..., 200) = 200
         +0 > P. 1:201(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 201:401(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 401:601(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 601:801(200) ack 1
      +.001 write(4, ..., 200) = 200
         +0 > P. 801:1001(200) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1001:1101(100) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1101:1201(100) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1201:1301(100) ack 1
      +.001 write(4, ..., 100) = 100
         +0 > P. 1301:1401(100) ack 1
      
      +.100 < . 1:1(0) ack 1 win 257 <nop,nop,sack 1001:1401>
      // Check that TCP collapse works :
         +0 > P. 1:1001(1000) ack 1
      Reported-by: NIlya Lesokhin <ilyal@mellanox.com>
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Neal Cardwell <ncardwell@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
      Acked-by: NNeal Cardwell <ncardwell@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2331ccc5
  17. 23 9月, 2016 1 次提交
    • D
      tcp: fix wrong checksum calculation on MTU probing · 2fe664f1
      Douglas Caetano dos Santos 提交于
      With TCP MTU probing enabled and offload TX checksumming disabled,
      tcp_mtu_probe() calculated the wrong checksum when a fragment being copied
      into the probe's SKB had an odd length. This was caused by the direct use
      of skb_copy_and_csum_bits() to calculate the checksum, as it pads the
      fragment being copied, if needed. When this fragment was not the last, a
      subsequent call used the previous checksum without considering this
      padding.
      
      The effect was a stale connection in one way, as even retransmissions
      wouldn't solve the problem, because the checksum was never recalculated for
      the full SKB length.
      Signed-off-by: NDouglas Caetano dos Santos <douglascs@taghos.com.br>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2fe664f1
  18. 22 9月, 2016 3 次提交
  19. 21 9月, 2016 4 次提交
  20. 17 9月, 2016 1 次提交
  21. 19 8月, 2016 1 次提交
  22. 31 7月, 2016 1 次提交
  23. 29 6月, 2016 1 次提交