nbd: use TCP_CORK in nbd_co_send_request()

Use TCP_CORK to defer packet transmission until both the header and the
payload have been written.

Suggested-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2013-04-15 16:14:47 +02:00 committed by Paolo Bonzini
parent 6760c47aa4
commit 0fcece25c0

View File

@ -334,14 +334,24 @@ static int nbd_co_send_request(BDRVNBDState *s, struct nbd_request *request,
s->send_coroutine = qemu_coroutine_self();
qemu_aio_set_fd_handler(s->sock, nbd_reply_ready, nbd_restart_write,
nbd_have_request, s);
if (qiov) {
if (!s->is_unix) {
socket_set_cork(s->sock, 1);
}
rc = nbd_send_request(s->sock, request);
if (rc >= 0 && qiov) {
if (rc >= 0) {
ret = qemu_co_sendv(s->sock, qiov->iov, qiov->niov,
offset, request->len);
if (ret != request->len) {
rc = -EIO;
}
}
if (!s->is_unix) {
socket_set_cork(s->sock, 0);
}
} else {
rc = nbd_send_request(s->sock, request);
}
qemu_aio_set_fd_handler(s->sock, nbd_reply_ready, NULL,
nbd_have_request, s);
s->send_coroutine = NULL;