kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

tcp_htcp: last_cong bug fix

Browse source 
This patch fixes a minor bug in tcp_htcp.c which has been
highlighted by Lachlan Andrew and Lawrence Stewart.  Currently, the
time since the last congestion event, which is stored in variable
last_cong, is reset whenever there is a state change into
TCP_CA_Open.  This includes transitions of the type
TCP_CA_Open->TCP_CA_Disorder->TCP_CA_Open which are not associated
with backoff of cwnd.  The patch changes last_cong to be updated
only on transitions into TCP_CA_Open that occur after experiencing
the congestion-related states TCP_CA_Loss, TCP_CA_Recovery,
TCP_CA_CWR.

Signed-off-by: Doug Leith <doug.leith@nuim.ie>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Doug Leith 2008-11-12 01:41:09 -08:00 committed by David S. Miller
parent d809a15956
commit 8f65b5354b
1 changed files with 10 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
net/ipv4/tcp_htcp.c
View file

@ -69,9 +69,12 @@ static u32 htcp_cwnd_undo(struct sock *sk)
const struct tcp_sock *tp = tcp_sk(sk);
struct htcp *ca = inet_csk_ca(sk);
ca->last_cong = ca->undo_last_cong;
ca->maxRTT = ca->undo_maxRTT;
ca->old_maxB = ca->undo_old_maxB;
if (ca->undo_last_cong) {
ca->last_cong = ca->undo_last_cong;
ca->maxRTT = ca->undo_maxRTT;
ca->old_maxB = ca->undo_old_maxB;
ca->undo_last_cong = 0;
}
return max(tp->snd_cwnd, (tp->snd_ssthresh << 7) / ca->beta);
}
@ -268,7 +271,10 @@ static void htcp_state(struct sock *sk, u8 new_state)
case TCP_CA_Open:
{
struct htcp *ca = inet_csk_ca(sk);
ca->last_cong = jiffies;
if (ca->undo_last_cong) {
ca->last_cong = jiffies;
ca->undo_last_cong = 0;
}
}
break;
case TCP_CA_CWR: