在 2022/5/14 21:35, Chengguang Xu 写道:
Hello Folks,
There is a logic(below code) in check_ack() in rxe_comp.c, the case
(AETH_NAK_PSN_SEQ_ERROR)
indicates sending side received a nak ack which means opposite side
had an psn seq error(expected psn < received psn).
I don't fully understand the comment(/* a nak implicitly acks all
packets with psns before */) here,
could someone give me a hint for this?
Carefully checking rxe_resp.c and found the psn in the ack (with
AETH_NAK_PSN_SEQ_ERROR) is resp.psn not received pkt->psn. :-)
Also, set qp->comp.psn as pkt->psn will skip some psns(from
qp->comp.psn to pkt->psn) in the retry, is it correct?
Many thanks in advance!
Chengguang
-------------------------
case AETH_NAK:
switch (syn) {
case AETH_NAK_PSN_SEQ_ERROR:
/* a nak implicitly acks all packets with psns
* before
*/
if (psn_compare(pkt->psn, qp->comp.psn) > 0) {
rxe_counter_inc(rxe,
RXE_CNT_RCV_SEQ_ERR);
qp->comp.psn = pkt->psn;
if (qp->req.wait_psn) {
qp->req.wait_psn = 0;
rxe_run_task(&qp->req.task, 0);
}
}
return COMPST_ERROR_RETRY;
