On 17-01-30 06:53 PM, Alexei Starovoitov wrote: > On 1/27/17 1:34 PM, John Fastabend wrote: >> + h2 = page_address(rx_buffer->page) + rx_buffer->page_offset - hdrlen; >> + eth = page_address(rx_buffer->page) + rx_buffer->page_offset, > > I don't think it compiles ;)
Well that is what I get for doing some last minute checkpatch fixes and not doing a build test before sending it out. Oh well just an RFC to get some general feedback. > >> + /* This indicates a bug in ixgbe leaving for testing purposes */ >> + WARN_ON(TP_STATUS_USER & h2->tp_status); >> + len = le16_to_cpu(rx_desc->wb.upper.length); >> + h2->tp_len = len; >> + h2->tp_snaplen = len; >> + h2->tp_mac = ALIGN(TPACKET_ALIGN(TPACKET2_HDRLEN), L1_CACHE_BYTES); >> + h2->tp_net = h2->tp_mac + ETH_HLEN; >> + h2->tp_sec = div_s64_rem(ns, NSEC_PER_SEC, &rem); >> + h2->tp_nsec = rem; >> + >> + sll = (void *)h2 + TPACKET_ALIGN(sizeof(struct tpacket2_hdr)); >> + sll->sll_halen = ETH_HLEN; >> + memcpy(sll->sll_addr, eth->h_source, ETH_ALEN); >> + sll->sll_family = AF_PACKET; >> + sll->sll_hatype = rx_ring->netdev->type; >> + sll->sll_protocol = eth->h_proto; >> + sll->sll_pkttype = PACKET_HOST; >> + sll->sll_ifindex = rx_ring->netdev->ifindex; > > performance wise it looks very expensive to do all these header copies > and integer divide for every packet. > I think unless we move to new dumb and simple header format > performance of this approach is not going to be satisfactory. > Sure I'm not opposed to moving to a v4 in fact I think it would help in a lot of ways. I'll try to fire off some benchmarks and then move to a v4 to see how that works out. .John
