[TCP]: Add two new spurious RTO responses to FRTO
New sysctl tcp_frto_response is added to select amongst these
responses:
- Rate halving based; reuses CA_CWR state (default)
- Very conservative; used to be the only one available (=1)
- Undo cwr; undoes ssthresh and cwnd reductions (=2)
The response with rate halving requires a new parameter to
tcp_enter_cwr because FRTO has already reduced ssthresh and
doing a second reduction there has to be prevented. In addition,
to keep things nice on 80 cols screen, a local variable was
added.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index d68effe..6817d64 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -647,6 +647,14 @@
.proc_handler = &proc_dointvec
},
{
+ .ctl_name = NET_TCP_FRTO_RESPONSE,
+ .procname = "tcp_frto_response",
+ .data = &sysctl_tcp_frto_response,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec
+ },
+ {
.ctl_name = NET_TCP_LOW_LATENCY,
.procname = "tcp_low_latency",
.data = &sysctl_tcp_low_latency,