1. 24 Mar, 2013 1 commit
    • Eric Dumazet's avatar
      net: remove a WARN_ON() in net_enable_timestamp() · 9979a55a
      Eric Dumazet authored
      The WARN_ON(in_interrupt()) in net_enable_timestamp() can get false
      positive, in socket clone path, run from softirq context :
      
      [ 3641.624425] WARNING: at net/core/dev.c:1532 net_enable_timestamp+0x7b/0x80()
      [ 3641.668811] Call Trace:
      [ 3641.671254]  <IRQ>  [<ffffffff80286817>] warn_slowpath_common+0x87/0xc0
      [ 3641.677871]  [<ffffffff8028686a>] warn_slowpath_null+0x1a/0x20
      [ 3641.683683]  [<ffffffff80742f8b>] net_enable_timestamp+0x7b/0x80
      [ 3641.689668]  [<ffffffff80732ce5>] sk_clone_lock+0x425/0x450
      [ 3641.695222]  [<ffffffff8078db36>] inet_csk_clone_lock+0x16/0x170
      [ 3641.701213]  [<ffffffff807ae449>] tcp_create_openreq_child+0x29/0x820
      [ 3641.707663]  [<ffffffff807d62e2>] ? ipt_do_table+0x222/0x670
      [ 3641.713354]  [<ffffffff807aaf5b>] tcp_v4_syn_recv_sock+0xab/0x3d0
      [ 3641.719425]  [<ffffffff807af63a>] tcp_check_req+0x3da/0x530
      [ 3641.724979]  [<ffffffff8078b400>] ? inet_hashinfo_init+0x60/0x80
      [ 3641.730964]  [<ffffffff807ade6f>] ? tcp_v4_rcv+0x79f/0xbe0
      [ 3641.736430]  [<ffffffff807ab9bd>] tcp_v4_do_rcv+0x38d/0x4f0
      [ 3641.741985]  [<ffffffff807ae14a>] tcp_v4_rcv+0xa7a/0xbe0
      
      Its safe at this point because the parent socket owns a reference
      on the netstamp_needed, so we cant have a 0 -> 1 transition, which
      requires to lock a mutex.
      
      Instead of refining the check, lets remove it, as all known callers
      are safe. If it ever changes in the future, static_key_slow_inc()
      will complain anyway.
      Reported-by: default avatarLaurent Chavey <chavey@google.com>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9979a55a
  2. 22 Mar, 2013 1 commit
    • Eric Dumazet's avatar
      tcp: preserve ACK clocking in TSO · f4541d60
      Eric Dumazet authored
      A long standing problem with TSO is the fact that tcp_tso_should_defer()
      rearms the deferred timer, while it should not.
      
      Current code leads to following bad bursty behavior :
      
      20:11:24.484333 IP A > B: . 297161:316921(19760) ack 1 win 119
      20:11:24.484337 IP B > A: . ack 263721 win 1117
      20:11:24.485086 IP B > A: . ack 265241 win 1117
      20:11:24.485925 IP B > A: . ack 266761 win 1117
      20:11:24.486759 IP B > A: . ack 268281 win 1117
      20:11:24.487594 IP B > A: . ack 269801 win 1117
      20:11:24.488430 IP B > A: . ack 271321 win 1117
      20:11:24.489267 IP B > A: . ack 272841 win 1117
      20:11:24.490104 IP B > A: . ack 274361 win 1117
      20:11:24.490939 IP B > A: . ack 275881 win 1117
      20:11:24.491775 IP B > A: . ack 277401 win 1117
      20:11:24.491784 IP A > B: . 316921:332881(15960) ack 1 win 119
      20:11:24.492620 IP B > A: . ack 278921 win 1117
      20:11:24.493448 IP B > A: . ack 280441 win 1117
      20:11:24.494286 IP B > A: . ack 281961 win 1117
      20:11:24.495122 IP B > A: . ack 283481 win 1117
      20:11:24.495958 IP B > A: . ack 285001 win 1117
      20:11:24.496791 IP B > A: . ack 286521 win 1117
      20:11:24.497628 IP B > A: . ack 288041 win 1117
      20:11:24.498459 IP B > A: . ack 289561 win 1117
      20:11:24.499296 IP B > A: . ack 291081 win 1117
      20:11:24.500133 IP B > A: . ack 292601 win 1117
      20:11:24.500970 IP B > A: . ack 294121 win 1117
      20:11:24.501388 IP B > A: . ack 295641 win 1117
      20:11:24.501398 IP A > B: . 332881:351881(19000) ack 1 win 119
      
      While the expected behavior is more like :
      
      20:19:49.259620 IP A > B: . 197601:202161(4560) ack 1 win 119
      20:19:49.260446 IP B > A: . ack 154281 win 1212
      20:19:49.261282 IP B > A: . ack 155801 win 1212
      20:19:49.262125 IP B > A: . ack 157321 win 1212
      20:19:49.262136 IP A > B: . 202161:206721(4560) ack 1 win 119
      20:19:49.262958 IP B > A: . ack 158841 win 1212
      20:19:49.263795 IP B > A: . ack 160361 win 1212
      20:19:49.264628 IP B > A: . ack 161881 win 1212
      20:19:49.264637 IP A > B: . 206721:211281(4560) ack 1 win 119
      20:19:49.265465 IP B > A: . ack 163401 win 1212
      20:19:49.265886 IP B > A: . ack 164921 win 1212
      20:19:49.266722 IP B > A: . ack 166441 win 1212
      20:19:49.266732 IP A > B: . 211281:215841(4560) ack 1 win 119
      20:19:49.267559 IP B > A: . ack 167961 win 1212
      20:19:49.268394 IP B > A: . ack 169481 win 1212
      20:19:49.269232 IP B > A: . ack 171001 win 1212
      20:19:49.269241 IP A > B: . 215841:221161(5320) ack 1 win 119
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Cc: Van Jacobson <vanj@google.com>
      Cc: Neal Cardwell <ncardwell@google.com>
      Cc: Nandita Dukkipati <nanditad@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f4541d60
  3. 21 Mar, 2013 9 commits
  4. 20 Mar, 2013 26 commits
  5. 19 Mar, 2013 3 commits