diff options
| author | Gerrit Renker <gerrit@erg.abdn.ac.uk> | 2007-11-24 21:44:30 -0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-01-28 14:54:55 -0800 |
| commit | b00d2bbc45a287c9a72374582ce42205f3412419 (patch) | |
| tree | 22a301fc6d05fe98b142cf53ec75967e847ac02e /net/dccp | |
| parent | e18d7a9857cb620a8f70622c4e400be477c264cf (diff) | |
| download | linux-b00d2bbc45a287c9a72374582ce42205f3412419.tar.bz2 | |
[CCID2]: Larger initial windows also for CCID2
RFC 4341, sec. 5 states that "The cwnd parameter is initialized to at most
four packets for new connections, following the rules from [RFC3390]", which
is implemented by this patch.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dccp')
| -rw-r--r-- | net/dccp/ccids/ccid2.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c index ef19fb834299..9c5b6c73f7c9 100644 --- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -741,15 +741,25 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk) { struct ccid2_hc_tx_sock *hctx = ccid_priv(ccid); + struct dccp_sock *dp = dccp_sk(sk); + u32 max_ratio; - ccid2_change_cwnd(hctx, 1); - /* Initialize ssthresh to infinity. This means that we will exit the - * initial slow-start after the first packet loss. This is what we - * want. - */ + /* RFC 4341, 5: initialise ssthresh to arbitrarily high (max) value */ hctx->ccid2hctx_ssthresh = ~0; hctx->ccid2hctx_numdupack = 3; + /* + * RFC 4341, 5: "The cwnd parameter is initialized to at most four + * packets for new connections, following the rules from [RFC3390]". + * We need to convert the bytes of RFC3390 into the packets of RFC 4341. + */ + hctx->ccid2hctx_cwnd = min(4U, max(2U, 4380U / dp->dccps_mss_cache)); + + /* Make sure that Ack Ratio is enabled and within bounds. */ + max_ratio = DIV_ROUND_UP(hctx->ccid2hctx_cwnd, 2); + if (dp->dccps_l_ack_ratio == 0 || dp->dccps_l_ack_ratio > max_ratio) + dp->dccps_l_ack_ratio = max_ratio; + /* XXX init ~ to window size... */ if (ccid2_hc_tx_alloc_seq(hctx)) return -ENOMEM; |