When a packet is received, the RSS hash is calculated if it is not already available. The Exact Match Cache (EMC) entry is then looked up using this RSS hash.
When a MPLSoGRE encapsulated packet is received, the GRE header is popped, the RSS hash is invalidated and the packet is recirculated for further processing. When the recirculated packet is processed, the MPLS header is popped and the packet is recirculated again. Since the RSS hash has not been invalidated here, the EMC lookup will hit the same entry as that after the first recirculation. This degrades performance severely. This patch invalides RSS hash after MPLS header is popped. Signed-off-by: Nitin Katiyar <nitin.kati...@ericsson.com> --- lib/packets.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/lib/packets.c b/lib/packets.c index ab0b1a3..35fa3c7 100644 --- a/lib/packets.c +++ b/lib/packets.c @@ -404,6 +404,11 @@ pop_mpls(struct dp_packet *packet, ovs_be16 ethtype) struct mpls_hdr *mh = dp_packet_l2_5(packet); size_t len = packet->l2_5_ofs; + /* Invalidate the hash so that it is recomputed using inner packet + * header after recirculation. Else it would cause EMC collision for + * packets recirculated after popping mpls header. */ + dp_packet_reset_offload(packet); + set_ethertype(packet, ethtype); if (get_16aligned_be32(&mh->mpls_lse) & htonl(MPLS_BOS_MASK)) { dp_packet_set_l2_5(packet, NULL); -- 1.9.1 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev