exit
fi
done
+From 30927520dbae297182990bb21d08762bcc35ce1d Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Wed, 9 Sep 2015 21:55:07 -0700
+Subject: [PATCH] tcp_cubic: better follow cubic curve after idle period
-diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
-index 7a0c800..ec5ebbb 100644
---- a/drivers/net/ethernet/realtek/r8169.c
-+++ b/drivers/net/ethernet/realtek/r8169.c
-@@ -4103,6 +4103,14 @@ rtl8169_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
- /* Get MAC address */
- for (i = 0; i < ETH_ALEN; i++)
- dev->dev_addr[i] = RTL_R8(MAC0 + i);
-+
-+ if (!is_valid_ether_addr(dev->dev_addr)) {
-+ /* Report it and use a random ethernet address instead */
-+ netdev_err(dev, "Invalid MAC address: %pM\n", dev->dev_addr);
-+ random_ether_addr(dev->dev_addr);
-+ netdev_info(dev, "Using random MAC address: %pM\n",
-+ dev->dev_addr);
-+ }
- memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
-
- SET_ETHTOOL_OPS(dev, &rtl8169_ethtool_ops);
---
-1.7.7.3
+Jana Iyengar found an interesting issue on CUBIC :
-
---- linux-3.4/fs/unionfs/commonfops.c.org 2012-05-29 20:40:20.756489877 +0200
-+++ linux-3.4/fs/unionfs/commonfops.c 2012-05-29 21:07:12.021252743 +0200
-@@ -766,7 +766,7 @@
- unsigned int cmd, unsigned long arg)
- {
- int err = 0;
-- fd_set branchlist;
-+ unsigned long branchlist = 0;
- int bstart = 0, bend = 0, bindex = 0;
- int orig_bstart, orig_bend;
- struct dentry *dentry, *lower_dentry;
-@@ -781,14 +781,12 @@
- bstart = dbstart(dentry);
- bend = dbend(dentry);
-
-- FD_ZERO(&branchlist);
--
- for (bindex = bstart; bindex <= bend; bindex++) {
- lower_dentry = unionfs_lower_dentry_idx(dentry, bindex);
- if (!lower_dentry)
- continue;
- if (likely(lower_dentry->d_inode))
-- FD_SET(bindex, &branchlist);
-+ __set_bit(bindex, &branchlist);
- /* purge any lower objects after partial_lookup */
- if (bindex < orig_bstart || bindex > orig_bend) {
- dput(lower_dentry);
---- linux-3.4.orig/drivers/acpi/apei/apei-base.c 2012-06-08 10:02:06.000000000 +0200
-+++ linux-3.4/drivers/acpi/apei/apei-base.c 2012-06-08 10:04:16.503779775 +0200
-@@ -586,6 +586,11 @@ static int apei_check_gar(struct acpi_ge
- }
- *access_bit_width = 1UL << (access_size_code + 2);
+The epoch is only updated/reset initially and when experiencing losses.
+The delta "t" of now - epoch_start can be arbitrary large after app idle
+as well as the bic_target. Consequentially the slope (inverse of
+ca->cnt) would be really large, and eventually ca->cnt would be
+lower-bounded in the end to 2 to have delayed-ACK slow-start behavior.
+
+This particularly shows up when slow_start_after_idle is disabled
+as a dangerous cwnd inflation (1.5 x RTT) after few seconds of idle
+time.
+
+Jana initial fix was to reset epoch_start if app limited,
+but Neal pointed out it would ask the CUBIC algorithm to recalculate the
+curve so that we again start growing steeply upward from where cwnd is
+now (as CUBIC does just after a loss). Ideally we'd want the cwnd growth
+curve to be the same shape, just shifted later in time by the amount of
+the idle period.
+
+Reported-by: Jana Iyengar <jri@google.com>
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Signed-off-by: Yuchung Cheng <ycheng@google.com>
+Signed-off-by: Neal Cardwell <ncardwell@google.com>
+Cc: Stephen Hemminger <stephen@networkplumber.org>
+Cc: Sangtae Ha <sangtae.ha@gmail.com>
+Cc: Lawrence Brakmo <lawrence@brakmo.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ net/ipv4/tcp_cubic.c | 16 ++++++++++++++++
+ 1 file changed, 16 insertions(+)
+
+diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
+index 28011fb1..c6ded6b 100644
+--- a/net/ipv4/tcp_cubic.c
++++ b/net/ipv4/tcp_cubic.c
+@@ -151,6 +151,21 @@ static void bictcp_init(struct sock *sk)
+ tcp_sk(sk)->snd_ssthresh = initial_ssthresh;
+ }
-+ /* Fixup common BIOS bug */
-+ if (bit_width == 32 && bit_offset == 0 && (*paddr & 0x03) == 0 &&
-+ *access_bit_width < 32)
-+ *access_bit_width = 32;
++static void bictcp_cwnd_event(struct sock *sk, enum tcp_ca_event event)
++{
++ if (event == CA_EVENT_TX_START) {
++ s32 delta = tcp_time_stamp - tcp_sk(sk)->lsndtime;
++ struct bictcp *ca = inet_csk_ca(sk);
++
++ /* We were application limited (idle) for a while.
++ * Shift epoch_start to keep cwnd growth to cubic curve.
++ */
++ if (ca->epoch_start && delta > 0)
++ ca->epoch_start += delta;
++ return;
++ }
++}
+
- if ((bit_width + bit_offset) > *access_bit_width) {
- pr_warning(FW_BUG APEI_PFX
- "Invalid bit width + offset in GAR [0x%llx/%u/%u/%u/%u]\n",
+ /* calculate the cubic root of x using a table lookup followed by one
+ * Newton-Raphson iteration.
+ * Avg err ~= 0.195%
+@@ -450,6 +465,7 @@ static struct tcp_congestion_ops cubictcp __read_mostly = {
+ .cong_avoid = bictcp_cong_avoid,
+ .set_state = bictcp_state,
+ .undo_cwnd = bictcp_undo_cwnd,
++ .cwnd_event = bictcp_cwnd_event,
+ .pkts_acked = bictcp_acked,
+ .owner = THIS_MODULE,
+ .name = "cubic",
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