kernel-small_fixes.patch

   1 --- linux-2.6.33/scripts/mod/modpost.c~ 2010-02-24 19:52:17.000000000 +0100
   2 +++ linux-2.6.33/scripts/mod/modpost.c  2010-03-07 14:26:47.242168558 +0100
   3 @@ -15,7 +15,8 @@
   4  #include <stdio.h>
   5  #include <ctype.h>
   6  #include "modpost.h"
   7 -#include "../../include/generated/autoconf.h"
   8 +// PLD architectures don't use CONFIG_SYMBOL_PREFIX
   9 +//#include "../../include/generated/autoconf.h"
  10  #include "../../include/linux/license.h"
  11
  12  /* Some toolchains use a `_' prefix for all user symbols. */
  13
  14 --- linux-3.0/scripts/kconfig/lxdialog/check-lxdialog.sh~       2011-07-22 04:17:23.000000000 +0200
  15 +++ linux-3.0/scripts/kconfig/lxdialog/check-lxdialog.sh        2011-08-25 21:26:04.799150642 +0200
  16 @@ -9,6 +9,12 @@
  17                         $cc -print-file-name=lib${lib}.${ext} | grep -q /
  18                         if [ $? -eq 0 ]; then
  19                                 echo "-l${lib}"
  20 +                               for libt in tinfow tinfo ; do
  21 +                                       $cc -print-file-name=lib${libt}.${ext} | grep -q /
  22 +                                       if [ $? -eq 0 ]; then
  23 +                                               echo "-l${libt}"
  24 +                                       fi
  25 +                               done
  26                                 exit
  27                         fi
  28                 done
  29 From 30927520dbae297182990bb21d08762bcc35ce1d Mon Sep 17 00:00:00 2001
  30 From: Eric Dumazet <edumazet@google.com>
  31 Date: Wed, 9 Sep 2015 21:55:07 -0700
  32 Subject: [PATCH] tcp_cubic: better follow cubic curve after idle period
  33
  34 Jana Iyengar found an interesting issue on CUBIC :
  35
  36 The epoch is only updated/reset initially and when experiencing losses.
  37 The delta "t" of now - epoch_start can be arbitrary large after app idle
  38 as well as the bic_target. Consequentially the slope (inverse of
  39 ca->cnt) would be really large, and eventually ca->cnt would be
  40 lower-bounded in the end to 2 to have delayed-ACK slow-start behavior.
  41
  42 This particularly shows up when slow_start_after_idle is disabled
  43 as a dangerous cwnd inflation (1.5 x RTT) after few seconds of idle
  44 time.
  45
  46 Jana initial fix was to reset epoch_start if app limited,
  47 but Neal pointed out it would ask the CUBIC algorithm to recalculate the
  48 curve so that we again start growing steeply upward from where cwnd is
  49 now (as CUBIC does just after a loss). Ideally we'd want the cwnd growth
  50 curve to be the same shape, just shifted later in time by the amount of
  51 the idle period.
  52
  53 Reported-by: Jana Iyengar <jri@google.com>
  54 Signed-off-by: Eric Dumazet <edumazet@google.com>
  55 Signed-off-by: Yuchung Cheng <ycheng@google.com>
  56 Signed-off-by: Neal Cardwell <ncardwell@google.com>
  57 Cc: Stephen Hemminger <stephen@networkplumber.org>
  58 Cc: Sangtae Ha <sangtae.ha@gmail.com>
  59 Cc: Lawrence Brakmo <lawrence@brakmo.org>
  60 Signed-off-by: David S. Miller <davem@davemloft.net>
  61 ---
  62  net/ipv4/tcp_cubic.c | 16 ++++++++++++++++
  63  1 file changed, 16 insertions(+)
  64
  65 diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
  66 index 28011fb1..c6ded6b 100644
  67 --- a/net/ipv4/tcp_cubic.c
  68 +++ b/net/ipv4/tcp_cubic.c
  69 @@ -151,6 +151,21 @@ static void bictcp_init(struct sock *sk)
  70                 tcp_sk(sk)->snd_ssthresh = initial_ssthresh;
  71  }
  72
  73 +static void bictcp_cwnd_event(struct sock *sk, enum tcp_ca_event event)
  74 +{
  75 +       if (event == CA_EVENT_TX_START) {
  76 +               s32 delta = tcp_time_stamp - tcp_sk(sk)->lsndtime;
  77 +               struct bictcp *ca = inet_csk_ca(sk);
  78 +
  79 +               /* We were application limited (idle) for a while.
  80 +                * Shift epoch_start to keep cwnd growth to cubic curve.
  81 +                */
  82 +               if (ca->epoch_start && delta > 0)
  83 +                       ca->epoch_start += delta;
  84 +               return;
  85 +       }
  86 +}
  87 +
  88  /* calculate the cubic root of x using a table lookup followed by one
  89   * Newton-Raphson iteration.
  90   * Avg err ~= 0.195%
  91 @@ -450,6 +465,7 @@ static struct tcp_congestion_ops cubictcp __read_mostly = {
  92         .cong_avoid     = bictcp_cong_avoid,
  93         .set_state      = bictcp_state,
  94         .undo_cwnd      = bictcp_undo_cwnd,
  95 +       .cwnd_event     = bictcp_cwnd_event,
  96         .pkts_acked     = bictcp_acked,
  97         .owner          = THIS_MODULE,
  98         .name           = "cubic",