1. 12 May, 2015 18 commits
  2. 11 May, 2015 20 commits
  3. 10 May, 2015 2 commits
    • Eric Dumazet's avatar
      codel: add ce_threshold attribute · 80ba92fa
      Eric Dumazet authored
      For DCTCP or similar ECN based deployments on fabrics with shallow
      buffers, hosts are responsible for a good part of the buffering.
      
      This patch adds an optional ce_threshold to codel & fq_codel qdiscs,
      so that DCTCP can have feedback from queuing in the host.
      
      A DCTCP enabled egress port simply have a queue occupancy threshold
      above which ECT packets get CE mark.
      
      In codel language this translates to a sojourn time, so that one doesn't
      have to worry about bytes or bandwidth but delays.
      
      This makes the host an active participant in the health of the whole
      network.
      
      This also helps experimenting DCTCP in a setup without DCTCP compliant
      fabric.
      
      On following example, ce_threshold is set to 1ms, and we can see from
      'ldelay xxx us' that TCP is not trying to go around the 5ms codel
      target.
      
      Queue has more capacity to absorb inelastic bursts (say from UDP
      traffic), as queues are maintained to an optimal level.
      
      lpaa23:~# ./tc -s -d qd sh dev eth1
      qdisc mq 1: dev eth1 root
       Sent 87910654696 bytes 58065331 pkt (dropped 0, overlimits 0 requeues 42961)
       backlog 3108242b 364p requeues 42961
      qdisc codel 8063: dev eth1 parent 1:1 limit 1000p target 5.0ms ce_threshold 1.0ms interval 100.0ms
       Sent 7363778701 bytes 4863809 pkt (dropped 0, overlimits 0 requeues 5503)
       rate 2348Mbit 193919pps backlog 255866b 46p requeues 5503
        count 0 lastcount 0 ldelay 1.0ms drop_next 0us
        maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 72384
      qdisc codel 8064: dev eth1 parent 1:2 limit 1000p target 5.0ms ce_threshold 1.0ms interval 100.0ms
       Sent 7636486190 bytes 5043942 pkt (dropped 0, overlimits 0 requeues 5186)
       rate 2319Mbit 191538pps backlog 207418b 64p requeues 5186
        count 0 lastcount 0 ldelay 694us drop_next 0us
        maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 69873
      qdisc codel 8065: dev eth1 parent 1:3 limit 1000p target 5.0ms ce_threshold 1.0ms interval 100.0ms
       Sent 11569360142 bytes 7641602 pkt (dropped 0, overlimits 0 requeues 5554)
       rate 3041Mbit 251096pps backlog 210446b 59p requeues 5554
        count 0 lastcount 0 ldelay 889us drop_next 0us
        maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 37780
      ...
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Florian Westphal <fw@strlen.de>
      Cc: Daniel Borkmann <daniel@iogearbox.net>
      Cc: Glenn Judd <glenn.judd@morganstanley.com>
      Cc: Nandita Dukkipati <nanditad@google.com>
      Cc: Neal Cardwell <ncardwell@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Acked-by: default avatarNeal Cardwell <ncardwell@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      80ba92fa
    • Varka Bhadram's avatar
      ethernet: qualcomm: use spi instead of spi_device · cf9d0dcc
      Varka Bhadram authored
      All spi based drivers have an instance of struct spi_device
      as spi. This patch renames spi_device to spi to synchronize
      with all the drivers.
      Signed-off-by: default avatarVarka Bhadram <varkab@cdac.in>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      cf9d0dcc