Hi, I just realized I've missed the "[PATCH]" tag from the subject. Did anyone had time to review this?
Regards, Zoltan On 01/09/15 20:17, Zoltan Kiss wrote: > The lack of this prefetch causes a significant performance drop in > OVS-DPDK: 13.3 Mpps instead of 14 when forwarding 64 byte packets. Even > though OVS prefetches the next packet's header before it starts processing > the current one, it doesn't get there fast enough. This aligns with the > behaviour of other receive functions. > > Signed-off-by: Zoltan Kiss <zoltan.kiss at linaro.org> > --- > diff --git a/drivers/net/ixgbe/ixgbe_rxtx_vec.c > b/drivers/net/ixgbe/ixgbe_rxtx_vec.c > index cf25a53..51299fa 100644 > --- a/drivers/net/ixgbe/ixgbe_rxtx_vec.c > +++ b/drivers/net/ixgbe/ixgbe_rxtx_vec.c > @@ -502,6 +502,15 @@ _recv_raw_pkts_vec(struct ixgbe_rx_queue *rxq, struct > rte_mbuf **rx_pkts, > _mm_storeu_si128((void > *)&rx_pkts[pos]->rx_descriptor_fields1, > pkt_mb1); > > + rte_packet_prefetch((char*)(rx_pkts[pos]->buf_addr) + > + RTE_PKTMBUF_HEADROOM); > + rte_packet_prefetch((char*)(rx_pkts[pos + 1]->buf_addr) + > + RTE_PKTMBUF_HEADROOM); > + rte_packet_prefetch((char*)(rx_pkts[pos + 2]->buf_addr) + > + RTE_PKTMBUF_HEADROOM); > + rte_packet_prefetch((char*)(rx_pkts[pos + 3]->buf_addr) + > + RTE_PKTMBUF_HEADROOM); > + > /* C.4 calc avaialbe number of desc */ > var = __builtin_popcountll(_mm_cvtsi128_si64(staterr)); > nb_pkts_recd += var; >
