Hi Cheng, > -----Original Message----- > From: jiangheng (G) <jianghen...@huawei.com> > Sent: Saturday, April 15, 2023 10:46 PM > To: us...@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; dev@dpdk.org > Subject: [GRO] check whether ip_id continuity needs to be checked when > two TCP packets are merged. > > Hi jiayu.hu > > It cannot be guaranteed that 16bit identification field of ip packets in the > same tcp stream will be continuous. > Please help check whether ip_id continuity needs to be checked when two > TCP packets are merged? > Seems to modify the following code, gro will aggregate better, and work > better: > > diff --git a/lib/gro/gro_tcp4.h b/lib/gro/gro_tcp4.h index > 212f97a042..06faead7b5 100644 > --- a/lib/gro/gro_tcp4.h > +++ b/lib/gro/gro_tcp4.h > @@ -291,12 +291,10 @@ check_seq_option(struct gro_tcp4_item *item, > /* check if the two packets are neighbors */ > len = pkt_orig->pkt_len - l2_offset - pkt_orig->l2_len - > pkt_orig->l3_len - tcp_hl_orig; > - if ((sent_seq == item->sent_seq + len) && (is_atomic || > - (ip_id == item->ip_id + 1))) > + if (sent_seq == item->sent_seq + len)
For atomic packets, the IP ID field is ignored, as it can be set in various ways. For non-atomic packets, it follows Linux kernel tcp_gro_receive(). Is this change specific to your case? Can you give more details on why it helps? Thanks, Jiayu > /* append the new packet */ > return 1; > - else if ((sent_seq + tcp_dl == item->sent_seq) && (is_atomic || > - (ip_id + item->nb_merged == item->ip_id))) > + else if (sent_seq + tcp_dl == item->sent_seq) > /* pre-pend the new packet */ > return -1;
