Eric Lee / smarc-fsl-linux-kernel

10 Mar, 2011

1 commit

29 Jan, 2008

1 commit

18 Jul, 2007

1 commit

04 May, 2007

1 commit

11 Feb, 2007

1 commit

23 Sep, 2006

1 commit

13 Jul, 2006

1 commit

  • 6150c22e2   [TCP] tcp_highspeed: Fix AI updates. ... Browse Code »

    I think there is still a problem with the AIMD parameter update in
    HighSpeed TCP code.

    Line 125~138 of the code (net/ipv4/tcp_highspeed.c):

    /* Update AIMD parameters */
    if (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd) {
    while (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd &&
    ca->ai < HSTCP_AIMD_MAX - 1)
    ca->ai++;
    } else if (tp->snd_cwnd < hstcp_aimd_vals[ca->ai].cwnd) {
    while (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd &&
    ca->ai > 0)
    ca->ai--;

    In fact, the second part (decreasing ca->ai) never decreases since the
    while loop's inequality is in the reverse direction. This leads to
    unfairness with multiple flows (once a flow happens to enjoy a higher
    ca->ai, it keeps enjoying that even its cwnd decreases)

    Here is a tentative fix (I also added a comment, trying to keep the
    change clear):

    Acked-by: Stephen Hemminger
    Signed-off-by: David S. Miller

    Xiaoliang (David) Wei
     

01 Jul, 2006

1 commit

18 Jun, 2006

1 commit

03 Jun, 2006

1 commit

06 May, 2006

1 commit

  • 5528e568a   [TCP]: Fix snd_cwnd adjustments in tcp_highspeed.c ... Browse Code »

    Xiaoliang (David) Wei wrote:
    > Hi gurus,
    >
    > I am reading the code of tcp_highspeed.c in the kernel and have a
    > question on the hstcp_cong_avoid function, specifically the following
    > AI part (line 136~143 in net/ipv4/tcp_highspeed.c ):
    >
    > /* Do additive increase */
    > if (tp->snd_cwnd < tp->snd_cwnd_clamp) {
    > tp->snd_cwnd_cnt += ca->ai;
    > if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
    > tp->snd_cwnd++;
    > tp->snd_cwnd_cnt -= tp->snd_cwnd;
    > }
    > }
    >
    > In this part, when (tp->snd_cwnd_cnt == tp->snd_cwnd),
    > snd_cwnd_cnt will be -1... snd_cwnd_cnt is defined as u16, will this
    > small chance of getting -1 becomes a problem?
    > Shall we change it by reversing the order of the cwnd++ and cwnd_cnt -=
    > cwnd?

    Absolutely correct. Thanks.

    Signed-off-by: John Heffner
    Signed-off-by: David S. Miller

    John Heffner
     

13 Mar, 2006

1 commit

18 Nov, 2005

1 commit

11 Nov, 2005

2 commits

  • 7faffa1c7   [TCP]: add tcp_slow_start helper ... Browse Code »

    Move all the code that does linear TCP slowstart to one
    inline function to ease later patch to add ABC support.

    Signed-off-by: Stephen Hemminger
    Signed-off-by: David S. Miller

    Stephen Hemminger
     
  • f4805eded   [TCP]: fix congestion window update when using TSO deferal ... Browse Code »

    TCP peformance with TSO over networks with delay is awful.
    On a 100Mbit link with 150ms delay, we get 4Mbits/sec with TSO and
    50Mbits/sec without TSO.

    The problem is with TSO, we intentionally do not keep the maximum
    number of packets in flight to fill the window, we hold out to until
    we can send a MSS chunk. But, we also don't update the congestion window
    unless we have filled, as per RFC2861.

    This patch replaces the check for the congestion window being full
    with something smarter that accounts for TSO.

    Signed-off-by: Stephen Hemminger
    Signed-off-by: David S. Miller

    Stephen Hemminger
     

30 Aug, 2005

1 commit

  • 6687e988d   [ICSK]: Move TCP congestion avoidance members to icsk ... Browse Code »

    This changeset basically moves tcp_sk()->{ca_ops,ca_state,etc} to inet_csk(),
    minimal renaming/moving done in this changeset to ease review.

    Most of it is just changes of struct tcp_sock * to struct sock * parameters.

    With this we move to a state closer to two interesting goals:

    1. Generalisation of net/ipv4/tcp_diag.c, becoming inet_diag.c, being used
    for any INET transport protocol that has struct inet_hashinfo and are
    derived from struct inet_connection_sock. Keeps the userspace API, that will
    just not display DCCP sockets, while newer versions of tools can support
    DCCP.

    2. INET generic transport pluggable Congestion Avoidance infrastructure, using
    the current TCP CA infrastructure with DCCP.

    Signed-off-by: Arnaldo Carvalho de Melo
    Signed-off-by: David S. Miller

    Arnaldo Carvalho de Melo
     

24 Jun, 2005

1 commit