> >> int
> >> rte_gso_segment(struct rte_mbuf *pkt,
> >> @@ -41,12 +46,53 @@
> >> struct rte_mbuf **pkts_out,
> >> uint16_t nb_pkts_out)
> >> {
> >> + struct rte_mempool *direct_pool, *indirect_pool;
> >> + struct rte_mbuf *pkt_seg;
> >> + uint64_t ol_flags;
> >> + uint16_t gso_size;
> >> + uint8_t ipid_delta;
> >> + int ret = 1;
> >> +
> >> if (pkt == NULL || pkts_out == NULL || gso_ctx == NULL ||
> >> nb_pkts_out < 1)
> >> return -EINVAL;
> >>
> >> - pkt->ol_flags &= (~PKT_TX_TCP_SEG);
> >> - pkts_out[0] = pkt;
> >> + if ((gso_ctx->gso_size >= pkt->pkt_len) || (gso_ctx->gso_types &
> >> + DEV_TX_OFFLOAD_TCP_TSO) !=
> >> + gso_ctx->gso_types) {
> >> + pkt->ol_flags &= (~PKT_TX_TCP_SEG);
> >> + pkts_out[0] = pkt;
> >> + return 1;
> >> + }
> >> +
> >> + direct_pool = gso_ctx->direct_pool;
> >> + indirect_pool = gso_ctx->indirect_pool;
> >> + gso_size = gso_ctx->gso_size;
> >> + ipid_delta = (gso_ctx->ipid_flag != RTE_GSO_IPID_FIXED);
> >> + ol_flags = pkt->ol_flags;
> >> +
> >> + if (IS_IPV4_TCP(pkt->ol_flags)) {
> >> + pkt->ol_flags &= (~PKT_TX_TCP_SEG);
> >> + ret = gso_tcp4_segment(pkt, gso_size, ipid_delta,
> >> + direct_pool, indirect_pool,
> >> + pkts_out, nb_pkts_out);
> >> + } else {
> >> + pkt->ol_flags &= (~PKT_TX_TCP_SEG);
> >
> >Not sure why do you clean this flag if you don't support that packet type
> >and no action was perfomed?
> >Suppose you have a mix ipv4 and ipv6 packets - gso lib would do ipv4 and
> >someone else
> >(HW?) can do ipv4 segmentation.
>
> I can't say for definite, since I didn't implement this change. However, I
> can only presume that the assumption here is that since
> segmentation is being done in S/W that the underlying H/W does not support
> TSO.
> Since the underlying HW can't segment the packet in HW, we should clear the
> flag; otherwise, if an mbuf marked for TCP segmentation is
> passed to the driver of a NIC that does not support/understand that feature,
> the behavior is undefined.
> Is this a fair assumption in your opinion, or is it the case that the packet
> would simply be transmitted un-segmented in that case, and so we
> shouldn't clear the flag?
Yes, I think if we shouldn't clear the flag if we didn't do any segmentation
(we just encounter a packet type that we don't support).
Konstantin
>
> Thanks again,
> Mark
>
> >BTW, did you notice that building of shared target fails?
> >Konstantin
>
> I didn't, but I'll take a look right now - thanks for the catch!
>
> >
> >
> >> + pkts_out[0] = pkt;
> >> + RTE_LOG(WARNING, GSO, "Unsupported packet type\n");
> >> + return 1;
> >> + }
> >> +
> >> + if (ret > 1) {
> >> + pkt_seg = pkt;
> >> + while (pkt_seg) {
> >> + rte_mbuf_refcnt_update(pkt_seg, -1);
> >> + pkt_seg = pkt_seg->next;
> >> + }
> >> + } else if (ret < 0) {
> >> + /* Revert the ol_flags in the event of failure. */
> >> + pkt->ol_flags = ol_flags;
> >> + }
> >>
> >> - return 1;
> >> + return ret;
> >> }
> >> --
> >> 1.9.3
