Unlike tcp_transmit_skb, sctp_packet_transmit does not set ooo_okay explicitly, causing unwanted Tx queue switching when multiqueue is in use; Tx queue switching may cause out-of-order packets. Change sctp_packet_transmit to allow Tx queue switching only for the first in flight packet, to avoid unwanted Tx queue switching. Signed-off-by: Wally Zhao <wallyzhao@xxxxxxxxx> --- net/sctp/output.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/sctp/output.c b/net/sctp/output.c index dbda7e7..5ff75cc 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -626,6 +626,10 @@ int sctp_packet_transmit(struct sctp_packet *packet, gfp_t gfp) /* neighbour should be confirmed on successful transmission or * positive error */ + + /* allow switch tx queue only for the first in flight pkt */ + head->ooo_okay = asoc->outqueue.outstanding_bytes == 0; + if (tp->af_specific->sctp_xmit(head, tp) >= 0 && tp->dst_pending_confirm) tp->dst_pending_confirm = 0; -- 1.8.3.1
