[PATCH v3 09/10] tcp: Send a duplicate ACK also on complete sendmsg() failure

...in order to trigger a fast retransmit as soon as possible. There's no benefit in forcing the sender to wait for a longer time than that. We already do this on partial failures (short socket writes), but for historical reason not on complete failures. Make these two cases consistent between each other. Signed-off-by: Stefano Brivio Reviewed-by: David Gibson --- tcp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tcp.c b/tcp.c index 07ef5f0..9c0fe42 100644 --- a/tcp.c +++ b/tcp.c @@ -2019,7 +2019,7 @@ eintr: goto eintr; if (errno == EAGAIN || errno == EWOULDBLOCK) { - tcp_send_flag(c, conn, ACK_IF_NEEDED); + tcp_send_flag(c, conn, ACK | DUP_ACK); return p->count - idx; } -- 2.43.0