[PATCH net 13/13] rxrpc: Don't request an ACK on the last DATA packet of a call's Tx phase
From: David Howells <dhowells@redhat.com>
Date: 2016-10-06 10:05:31
Also in:
lkml
Subsystem:
networking [general], rxrpc sockets (af_rxrpc), the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Howells, Marc Dionne, Linus Torvalds
Don't request an ACK on the last DATA packet of a call's Tx phase as for a client there will be a reply packet or some sort of ACK to shift phase. If the ACK is requested, OpenAFS sends a REQUESTED-ACK ACK with soft-ACKs in it and doesn't follow up with a hard-ACK. If we don't set the flag, OpenAFS will send a DELAY ACK that hard-ACKs the reply data, thereby allowing the call to terminate cleanly. Signed-off-by: David Howells <dhowells@redhat.com> --- net/rxrpc/output.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index a12cea0cbc05..5dab1ff3a6c2 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c@@ -307,11 +307,12 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb, /* If our RTT cache needs working on, request an ACK. Also request * ACKs if a DATA packet appears to have been lost. */ - if (retrans || - call->cong_mode == RXRPC_CALL_SLOW_START || - (call->peer->rtt_usage < 3 && sp->hdr.seq & 1) || - ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), - ktime_get_real())) + if (!(sp->hdr.flags & RXRPC_LAST_PACKET) && + (retrans || + call->cong_mode == RXRPC_CALL_SLOW_START || + (call->peer->rtt_usage < 3 && sp->hdr.seq & 1) || + ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), + ktime_get_real()))) whdr.flags |= RXRPC_REQUEST_ACK; if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {