Looks good to me. Some comments below
On Fri, Nov 09, 2018 at 04:58:27PM +0200, Yuri Benditovich wrote:
> This commit adds implementation of RX packets
> coalescing, compatible with requirements of Windows
> Hardware compatibility kit.
>
> The device enables feature VIRTIO_NET_F_RSC_EXT in
> host features if it supports extended RSC functionality
> as defined in the specification.
> This feature requires at least one of VIRTIO_NET_F_GUEST_TSO4,
> VIRTIO_NET_F_GUEST_TSO6. Windows guest driver acks
> this feature only if VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
> is also present.
>
> In case vhost is enabled the feature bit is cleared in
> host_features during device initialization.
>
> If the guest driver acks VIRTIO_NET_F_RSC_EXT feature,
> the device coalesces TCPv4 and TCPv6 packets (if
> respective VIRTIO_NET_F_GUEST_TSO feature is on,
> populates extended RSC information in virtio header
> and sets VIRTIO_NET_HDR_F_RSC_INFO bit in header flags.
> The device does not recalculate checksums in the coalesced
> packet, so they are not valid.
>
> In this case:
> All the data packets in a tcp connection are cached
> to a single buffer in every receive interval, and will
> be sent out via a timer, the 'virtio_net_rsc_timeout'
> controls the interval, this value may impact the
> performance and response time of tcp connection,
> 50000(50us) is an experience value to gain a performance
> improvement, since the whql test sends packets every 100us,
> so '300000(300us)' passes the test case, it is the default
> value as well, tune it via the command line parameter
> 'rsc_interval' within 'virtio-net-pci' device, for example,
> to launch a guest with interval set as '500000':
>
> 'virtio-net-pci,netdev=hostnet1,bus=pci.0,id=net1,mac=00,
> guest_rsc_ext=on,rsc_interval=500000'
>
> The timer will only be triggered if the packets pool is not empty,
> and it'll drain off all the cached packets.
>
> 'NetRscChain' is used to save the segments of IPv4/6 in a
> VirtIONet device.
>
> A new segment becomes a 'Candidate' as well as it passed sanity check,
> the main handler of TCP includes TCP window update, duplicated
> ACK check and the real data coalescing.
>
> An 'Candidate' segment means:
> 1. Segment is within current window and the sequence is the expected one.
> 2. 'ACK' of the segment is in the valid window.
>
> Sanity check includes:
> 1. Incorrect version in IP header
> 2. An IP options or IP fragment
> 3. Not a TCP packet
> 4. Sanity size check to prevent buffer overflow attack.
> 5. An ECN packet
>
> Even though, there might more cases should be considered such as
> ip identification other flags, while it breaks the test because
> windows set it to the same even it's not a fragment.
>
> Normally it includes 2 typical ways to handle a TCP control flag,
> 'bypass' and 'finalize', 'bypass' means should be sent out directly,
> while 'finalize' means the packets should also be bypassed, but this
> should be done after search for the same connection packets in the
> pool and drain all of them out, this is to avoid out of order fragment.
>
> All the 'SYN' packets will be bypassed since this always begin a new'
> connection, other flags such 'URG/FIN/RST/CWR/ECE' will trigger a
> finalization, because this normally happens upon a connection is going
> to be closed, an 'URG' packet also finalize current coalescing unit.
>
> Statistics can be used to monitor the basic coalescing status, the
> 'out of order' and 'out of window' means how many retransmitting packets,
> thus describe the performance intuitively.
>
> Difference between ip v4 and v6 processing:
> Fragment length in ipv4 header includes itself, while it's not
> included for ipv6, thus means ipv6 can carry a real 65535 payload.
>
> Signed-off-by: Wei Xu <address@hidden>
Pls put in the full address, QEMU doesn't accept anonymous
code donations.
> Signed-off-by: Yuri Benditovich <yuri.benditov...@daynix.com>
> ---
> hw/net/virtio-net.c | 648 +++++++++++++++++++-
> include/hw/virtio/virtio-net.h | 81 +++
> include/net/eth.h | 2 +
> include/standard-headers/linux/virtio_net.h | 8 +
> 4 files changed, 734 insertions(+), 5 deletions(-)
>
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index 385b1a03e9..43a7021409 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -41,6 +41,28 @@
> #define VIRTIO_NET_RX_QUEUE_MIN_SIZE VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE
> #define VIRTIO_NET_TX_QUEUE_MIN_SIZE VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE
>
> +#define VIRTIO_NET_IP4_ADDR_SIZE 8 /* ipv4 saddr + daddr */
> +
> +#define VIRTIO_NET_TCP_FLAG 0x3F
> +#define VIRTIO_NET_TCP_HDR_LENGTH 0xF000
> +
> +/* IPv4 max payload, 16 bits in the header */
> +#define VIRTIO_NET_MAX_IP4_PAYLOAD (65535 - sizeof(struct ip_header))
> +#define VIRTIO_NET_MAX_TCP_PAYLOAD 65535
> +
> +/* header length value in ip header without option */
> +#define VIRTIO_NET_IP4_HEADER_LENGTH 5
> +
> +#define ETH_IP6_HDR_SZ (ETH_HDR_SZ + IP6_HDR_SZ)
is this used anywhere?
> +#define VIRTIO_NET_IP6_ADDR_SIZE 32 /* ipv6 saddr + daddr */
> +#define VIRTIO_NET_MAX_IP6_PAYLOAD VIRTIO_NET_MAX_TCP_PAYLOAD
> +
> +/* Purge coalesced packets timer interval, This value affects the performance
> + a lot, and should be tuned carefully, '300000'(300us) is the recommended
> + value to pass the WHQL test, '50000' can gain 2x netperf throughput with
> + tso/gso/gro 'off'. */
> +#define VIRTIO_NET_RSC_INTERVAL 300000
Maybe _DEFAULT_INTERVAL ?
> +
> /*
> * Calculate the number of bytes up to and including the given 'field' of
> * 'container'.
> @@ -628,6 +650,9 @@ static uint64_t virtio_net_get_features(VirtIODevice
> *vdev, uint64_t features,
> if (!get_vhost_net(nc->peer)) {
> return features;
> }
> + /* clear RSC_EXT feature in case of VHOST*/
space before *
> + virtio_clear_feature(&features, VIRTIO_NET_F_RSC_EXT);
> +
why is vhost special?
> features = vhost_net_get_features(get_vhost_net(nc->peer), features);
> vdev->backend_features = features;
>
> @@ -701,6 +726,11 @@ static void virtio_net_set_features(VirtIODevice *vdev,
> uint64_t features)
> virtio_has_feature(features,
> VIRTIO_F_VERSION_1));
>
> + n->rsc4_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT) &&
> + virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO4);
> + n->rsc6_enabled = virtio_has_feature(features, VIRTIO_NET_F_RSC_EXT) &&
> + virtio_has_feature(features, VIRTIO_NET_F_GUEST_TSO6);
> +
> if (n->has_vnet_hdr) {
> n->curr_guest_offloads =
> virtio_net_guest_offloads_by_features(features);
> @@ -781,6 +811,12 @@ static int virtio_net_handle_offloads(VirtIONet *n,
> uint8_t cmd,
> return VIRTIO_NET_ERR;
> }
>
> + n->rsc4_enabled = virtio_has_feature(offloads, VIRTIO_NET_F_RSC_EXT)
> &&
> + virtio_has_feature(offloads, VIRTIO_NET_F_GUEST_TSO4);
> + n->rsc6_enabled = virtio_has_feature(offloads, VIRTIO_NET_F_RSC_EXT)
> &&
> + virtio_has_feature(offloads, VIRTIO_NET_F_GUEST_TSO6);
> + virtio_clear_feature(&offloads, VIRTIO_NET_F_RSC_EXT);
> +
> supported_offloads = virtio_net_supported_guest_offloads(n);
> if (offloads & ~supported_offloads) {
> return VIRTIO_NET_ERR;
> @@ -1253,6 +1289,7 @@ static ssize_t virtio_net_receive_rcu(NetClientState
> *nc, const uint8_t *buf,
> }
>
> receive_header(n, sg, elem->in_num, buf, size);
> +
> offset = n->host_hdr_len;
> total += n->guest_hdr_len;
> guest_offset = n->guest_hdr_len;
let's not do unrelated whitespace tweaks pls
> @@ -1292,7 +1329,7 @@ static ssize_t virtio_net_receive_rcu(NetClientState
> *nc, const uint8_t *buf,
> return size;
> }
>
> -static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf,
> +static ssize_t virtio_net_do_receive(NetClientState *nc, const uint8_t *buf,
> size_t size)
> {
> ssize_t r;
> @@ -1303,6 +1340,601 @@ static ssize_t virtio_net_receive(NetClientState *nc,
> const uint8_t *buf,
> return r;
> }
>
> +static void virtio_net_rsc_extract_unit4(NetRscChain *chain,
> + const uint8_t *buf, NetRscUnit*
> unit)
space before * not after
> +{
> + uint16_t ip_hdrlen;
> + struct ip_header *ip;
> +
> + ip = (struct ip_header *)(buf + chain->n->guest_hdr_len
> + + sizeof(struct eth_header));
> + unit->ip = (void *)ip;
> + ip_hdrlen = (ip->ip_ver_len & 0xF) << 2;
> + unit->ip_plen = &ip->ip_len;
> + unit->tcp = (struct tcp_header *)(((uint8_t *)unit->ip) + ip_hdrlen);
> + unit->tcp_hdrlen = (htons(unit->tcp->th_offset_flags) & 0xF000) >> 10;
> + unit->payload = htons(*unit->ip_plen) - ip_hdrlen - unit->tcp_hdrlen;
> +}
> +
> +static void virtio_net_rsc_extract_unit6(NetRscChain *chain,
> + const uint8_t *buf, NetRscUnit*
> unit)
> +{
> + struct ip6_header *ip6;
> +
> + ip6 = (struct ip6_header *)(buf + chain->n->guest_hdr_len
> + + sizeof(struct eth_header));
> + unit->ip = ip6;
> + unit->ip_plen = &(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen);
> + unit->tcp = (struct tcp_header *)(((uint8_t *)unit->ip)\
> + + sizeof(struct ip6_header));
> + unit->tcp_hdrlen = (htons(unit->tcp->th_offset_flags) & 0xF000) >> 10;
> +
> + /* There is a difference between payload lenght in ipv4 and v6,
> + ip header is excluded in ipv6 */
> + unit->payload = htons(*unit->ip_plen) - unit->tcp_hdrlen;
> +}
> +
> +static size_t virtio_net_rsc_drain_seg(NetRscChain *chain, NetRscSeg *seg)
> +{
> + int ret;
> + struct virtio_net_hdr *h;
> +
> + h = (struct virtio_net_hdr *)seg->buf;
> + h->flags = 0;
> + h->gso_type = VIRTIO_NET_HDR_GSO_NONE;
> +
> + if (seg->is_coalesced) {
> + h->rsc_ext_num_packets = seg->packets;
> + h->rsc_ext_num_dupacks = seg->dup_ack;
> + h->flags = VIRTIO_NET_HDR_F_RSC_INFO;
> + if (chain->proto == ETH_P_IP) {
> + h->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
> + } else {
> + h->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
> + }
> + }
> +
> + ret = virtio_net_do_receive(seg->nc, seg->buf, seg->size);
> + QTAILQ_REMOVE(&chain->buffers, seg, next);
> + g_free(seg->buf);
> + g_free(seg);
> +
> + return ret;
> +}
> +
> +static void virtio_net_rsc_purge(void *opq)
> +{
> + NetRscSeg *seg, *rn;
> + NetRscChain *chain = (NetRscChain *)opq;
> +
> + QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, rn) {
> + if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
> + chain->stat.purge_failed++;
> + continue;
> + }
> + }
> +
> + chain->stat.timer++;
> + if (!QTAILQ_EMPTY(&chain->buffers)) {
> + timer_mod(chain->drain_timer,
> + qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
> + }
> +}
> +
> +static void virtio_net_rsc_cleanup(VirtIONet *n)
> +{
> + NetRscChain *chain, *rn_chain;
> + NetRscSeg *seg, *rn_seg;
> +
> + QTAILQ_FOREACH_SAFE(chain, &n->rsc_chains, next, rn_chain) {
> + QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, rn_seg) {
> + QTAILQ_REMOVE(&chain->buffers, seg, next);
> + g_free(seg->buf);
> + g_free(seg);
> + }
> +
> + timer_del(chain->drain_timer);
> + timer_free(chain->drain_timer);
> + QTAILQ_REMOVE(&n->rsc_chains, chain, next);
> + g_free(chain);
> + }
> +}
> +
> +static void virtio_net_rsc_cache_buf(NetRscChain *chain, NetClientState *nc,
> + const uint8_t *buf, size_t size)
> +{
> + uint16_t hdr_len;
> + NetRscSeg *seg;
> +
> + hdr_len = chain->n->guest_hdr_len;
> + seg = g_malloc(sizeof(NetRscSeg));
> + seg->buf = g_malloc(hdr_len + sizeof(struct eth_header)
> + + sizeof(struct ip6_header) + VIRTIO_NET_MAX_TCP_PAYLOAD);
> + memcpy(seg->buf, buf, size);
> + seg->size = size;
> + seg->packets = 1;
> + seg->dup_ack = 0;
> + seg->is_coalesced = 0;
> + seg->nc = nc;
> +
> + QTAILQ_INSERT_TAIL(&chain->buffers, seg, next);
> + chain->stat.cache++;
> +
> + switch (chain->proto) {
> + case ETH_P_IP:
> + virtio_net_rsc_extract_unit4(chain, seg->buf, &seg->unit);
> + break;
> + case ETH_P_IPV6:
> + virtio_net_rsc_extract_unit6(chain, seg->buf, &seg->unit);
> + break;
> + default:
> + g_assert_not_reached();
> + }
> +}
> +
> +static int32_t virtio_net_rsc_handle_ack(NetRscChain *chain,
> + NetRscSeg *seg, const uint8_t *buf,
> + struct tcp_header *n_tcp,
> + struct tcp_header *o_tcp)
> +{
> + uint32_t nack, oack;
> + uint16_t nwin, owin;
> +
> + nack = htonl(n_tcp->th_ack);
> + nwin = htons(n_tcp->th_win);
> + oack = htonl(o_tcp->th_ack);
> + owin = htons(o_tcp->th_win);
> +
> + if ((nack - oack) >= VIRTIO_NET_MAX_TCP_PAYLOAD) {
> + chain->stat.ack_out_of_win++;
> + return RSC_FINAL;
> + } else if (nack == oack) {
> + /* duplicated ack or window probe */
> + if (nwin == owin) {
> + /* duplicated ack, add dup ack count due to whql test up to 1 */
> + chain->stat.dup_ack++;
> + return RSC_FINAL;
> + } else {
> + /* Coalesce window update */
> + o_tcp->th_win = n_tcp->th_win;
> + chain->stat.win_update++;
> + return RSC_COALESCE;
> + }
> + } else {
> + /* pure ack, go to 'C', finalize*/
> + chain->stat.pure_ack++;
> + return RSC_FINAL;
> + }
> +}
> +
> +static int32_t virtio_net_rsc_coalesce_data(NetRscChain *chain,
> + NetRscSeg *seg, const uint8_t
> *buf,
> + NetRscUnit *n_unit)
> +{
> + void *data;
> + uint16_t o_ip_len;
> + uint32_t nseq, oseq;
> + NetRscUnit *o_unit;
> +
> + o_unit = &seg->unit;
> + o_ip_len = htons(*o_unit->ip_plen);
> + nseq = htonl(n_unit->tcp->th_seq);
> + oseq = htonl(o_unit->tcp->th_seq);
> +
> + /* out of order or retransmitted. */
> + if ((nseq - oseq) > VIRTIO_NET_MAX_TCP_PAYLOAD) {
> + chain->stat.data_out_of_win++;
> + return RSC_FINAL;
> + }
> +
> + data = ((uint8_t *)n_unit->tcp) + n_unit->tcp_hdrlen;
> + if (nseq == oseq) {
> + if ((o_unit->payload == 0) && n_unit->payload) {
> + /* From no payload to payload, normal case, not a dup ack or etc
> */
> + chain->stat.data_after_pure_ack++;
> + goto coalesce;
> + } else {
> + return virtio_net_rsc_handle_ack(chain, seg, buf,
> + n_unit->tcp, o_unit->tcp);
> + }
> + } else if ((nseq - oseq) != o_unit->payload) {
> + /* Not a consistent packet, out of order */
> + chain->stat.data_out_of_order++;
> + return RSC_FINAL;
> + } else {
> +coalesce:
> + if ((o_ip_len + n_unit->payload) > chain->max_payload) {
> + chain->stat.over_size++;
> + return RSC_FINAL;
> + }
> +
> + /* Here comes the right data, the payload length in v4/v6 is
> different,
> + so use the field value to update and record the new data len */
> + o_unit->payload += n_unit->payload; /* update new data len */
> +
> + /* update field in ip header */
> + *o_unit->ip_plen = htons(o_ip_len + n_unit->payload);
> +
> + /* Bring 'PUSH' big, the whql test guide says 'PUSH' can be coalesced
> + for windows guest, while this may change the behavior for linux
> + guest (only if it uses RSC feature). */
> + o_unit->tcp->th_offset_flags = n_unit->tcp->th_offset_flags;
> +
> + o_unit->tcp->th_ack = n_unit->tcp->th_ack;
> + o_unit->tcp->th_win = n_unit->tcp->th_win;
> +
> + memmove(seg->buf + seg->size, data, n_unit->payload);
> + seg->size += n_unit->payload;
> + seg->packets++;
> + chain->stat.coalesced++;
> + return RSC_COALESCE;
> + }
> +}
> +
> +static int32_t virtio_net_rsc_coalesce4(NetRscChain *chain, NetRscSeg *seg,
> + const uint8_t *buf, size_t size,
> + NetRscUnit *unit)
> +{
> + struct ip_header *ip1, *ip2;
> +
> + ip1 = (struct ip_header *)(unit->ip);
> + ip2 = (struct ip_header *)(seg->unit.ip);
> + if ((ip1->ip_src ^ ip2->ip_src) || (ip1->ip_dst ^ ip2->ip_dst)
> + || (unit->tcp->th_sport ^ seg->unit.tcp->th_sport)
> + || (unit->tcp->th_dport ^ seg->unit.tcp->th_dport)) {
> + chain->stat.no_match++;
> + return RSC_NO_MATCH;
> + }
> +
> + return virtio_net_rsc_coalesce_data(chain, seg, buf, unit);
> +}
> +
> +static int32_t virtio_net_rsc_coalesce6(NetRscChain *chain, NetRscSeg *seg,
> + const uint8_t *buf, size_t size, NetRscUnit *unit)
> +{
> + struct ip6_header *ip1, *ip2;
> +
> + ip1 = (struct ip6_header *)(unit->ip);
> + ip2 = (struct ip6_header *)(seg->unit.ip);
> + if (memcmp(&ip1->ip6_src, &ip2->ip6_src, sizeof(struct in6_address))
> + || memcmp(&ip1->ip6_dst, &ip2->ip6_dst, sizeof(struct in6_address))
> + || (unit->tcp->th_sport ^ seg->unit.tcp->th_sport)
> + || (unit->tcp->th_dport ^ seg->unit.tcp->th_dport)) {
> + chain->stat.no_match++;
> + return RSC_NO_MATCH;
> + }
> +
> + return virtio_net_rsc_coalesce_data(chain, seg, buf, unit);
> +}
> +
> +/* Packets with 'SYN' should bypass, other flag should be sent after drain
> + * to prevent out of order */
> +static int virtio_net_rsc_tcp_ctrl_check(NetRscChain *chain,
> + struct tcp_header *tcp)
> +{
> + uint16_t tcp_hdr;
> + uint16_t tcp_flag;
> +
> + tcp_flag = htons(tcp->th_offset_flags);
> + tcp_hdr = (tcp_flag & VIRTIO_NET_TCP_HDR_LENGTH) >> 10;
> + tcp_flag &= VIRTIO_NET_TCP_FLAG;
> + tcp_flag = htons(tcp->th_offset_flags) & 0x3F;
> + if (tcp_flag & TH_SYN) {
> + chain->stat.tcp_syn++;
> + return RSC_BYPASS;
> + }
> +
> + if (tcp_flag & (TH_FIN | TH_URG | TH_RST | TH_ECE | TH_CWR)) {
> + chain->stat.tcp_ctrl_drain++;
> + return RSC_FINAL;
> + }
> +
> + if (tcp_hdr > sizeof(struct tcp_header)) {
> + chain->stat.tcp_all_opt++;
> + return RSC_FINAL;
> + }
> +
> + return RSC_CANDIDATE;
> +}
> +
> +static size_t virtio_net_rsc_do_coalesce(NetRscChain *chain,
> + NetClientState *nc,
> + const uint8_t *buf, size_t size,
> + NetRscUnit *unit)
> +{
> + int ret;
> + NetRscSeg *seg, *nseg;
> +
> + if (QTAILQ_EMPTY(&chain->buffers)) {
> + chain->stat.empty_cache++;
> + virtio_net_rsc_cache_buf(chain, nc, buf, size);
> + timer_mod(chain->drain_timer,
> + qemu_clock_get_ns(QEMU_CLOCK_HOST) + chain->n->rsc_timeout);
> + return size;
> + }
> +
> + QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
> + if (chain->proto == ETH_P_IP) {
> + ret = virtio_net_rsc_coalesce4(chain, seg, buf, size, unit);
> + } else {
> + ret = virtio_net_rsc_coalesce6(chain, seg, buf, size, unit);
> + }
> +
> + if (ret == RSC_FINAL) {
> + if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
> + /* Send failed */
> + chain->stat.final_failed++;
> + return 0;
> + }
> +
> + /* Send current packet */
> + return virtio_net_do_receive(nc, buf, size);
> + } else if (ret == RSC_NO_MATCH) {
> + continue;
> + } else {
> + /* Coalesced, mark coalesced flag to tell calc cksum for ipv4 */
> + seg->is_coalesced = 1;
> + return size;
> + }
> + }
> +
> + chain->stat.no_match_cache++;
> + virtio_net_rsc_cache_buf(chain, nc, buf, size);
> + return size;
> +}
> +
> +/* Drain a connection data, this is to avoid out of order segments */
> +static size_t virtio_net_rsc_drain_flow(NetRscChain *chain, NetClientState
> *nc,
> + const uint8_t *buf, size_t size,
> + uint16_t ip_start, uint16_t ip_size,
> + uint16_t tcp_port)
> +{
> + NetRscSeg *seg, *nseg;
> + uint32_t ppair1, ppair2;
> +
> + ppair1 = *(uint32_t *)(buf + tcp_port);
> + QTAILQ_FOREACH_SAFE(seg, &chain->buffers, next, nseg) {
> + ppair2 = *(uint32_t *)(seg->buf + tcp_port);
> + if (memcmp(buf + ip_start, seg->buf + ip_start, ip_size)
> + || (ppair1 != ppair2)) {
> + continue;
> + }
> + if (virtio_net_rsc_drain_seg(chain, seg) == 0) {
> + chain->stat.drain_failed++;
> + }
> +
> + break;
> + }
> +
> + return virtio_net_do_receive(nc, buf, size);
> +}
> +
> +static int32_t virtio_net_rsc_sanity_check4(NetRscChain *chain,
> + struct ip_header *ip,
> + const uint8_t *buf, size_t size)
> +{
> + uint16_t ip_len;
> +
> + /* Not an ipv4 packet */
> + if (((ip->ip_ver_len & 0xF0) >> 4) != IP_HEADER_VERSION_4) {
> + chain->stat.ip_option++;
> + return RSC_BYPASS;
> + }
> +
> + /* Don't handle packets with ip option */
> + if ((ip->ip_ver_len & 0xF) != VIRTIO_NET_IP4_HEADER_LENGTH) {
> + chain->stat.ip_option++;
> + return RSC_BYPASS;
> + }
> +
> + if (ip->ip_p != IPPROTO_TCP) {
> + chain->stat.bypass_not_tcp++;
> + return RSC_BYPASS;
> + }
> +
> + /* Don't handle packets with ip fragment */
> + if (!(htons(ip->ip_off) & IP_DF)) {
> + chain->stat.ip_frag++;
> + return RSC_BYPASS;
> + }
> +
> + /* Don't handle packets with ecn flag */
> + if (IPTOS_ECN(ip->ip_tos)) {
> + chain->stat.ip_ecn++;
> + return RSC_BYPASS;
> + }
> +
> + ip_len = htons(ip->ip_len);
> + if (ip_len < (sizeof(struct ip_header) + sizeof(struct tcp_header))
> + || ip_len > (size - chain->n->guest_hdr_len -
> + sizeof(struct eth_header))) {
> + chain->stat.ip_hacked++;
> + return RSC_BYPASS;
> + }
> +
> + return RSC_CANDIDATE;
> +}
> +
> +static size_t virtio_net_rsc_receive4(NetRscChain *chain, NetClientState* nc,
> + const uint8_t *buf, size_t size)
> +{
> + int32_t ret;
> + uint16_t hdr_len;
> + NetRscUnit unit;
> +
> + hdr_len = ((VirtIONet *)(chain->n))->guest_hdr_len;
> +
> + if (size < (hdr_len + sizeof(struct eth_header) + sizeof(struct
> ip_header)
> + + sizeof(struct tcp_header))) {
> + chain->stat.bypass_not_tcp++;
> + return virtio_net_do_receive(nc, buf, size);
> + }
> +
> + virtio_net_rsc_extract_unit4(chain, buf, &unit);
> + if (virtio_net_rsc_sanity_check4(chain, unit.ip, buf, size)
> + != RSC_CANDIDATE) {
> + return virtio_net_do_receive(nc, buf, size);
> + }
> +
> + ret = virtio_net_rsc_tcp_ctrl_check(chain, unit.tcp);
> + if (ret == RSC_BYPASS) {
> + return virtio_net_do_receive(nc, buf, size);
> + } else if (ret == RSC_FINAL) {
> + return virtio_net_rsc_drain_flow(chain, nc, buf, size,
> + ((hdr_len + sizeof(struct eth_header)) + 12),
> + VIRTIO_NET_IP4_ADDR_SIZE,
> + hdr_len + sizeof(struct eth_header) + sizeof(struct
> ip_header));
> + }
> +
> + return virtio_net_rsc_do_coalesce(chain, nc, buf, size, &unit);
> +}
> +
> +static int32_t virtio_net_rsc_sanity_check6(NetRscChain *chain,
> + struct ip6_header *ip6,
> + const uint8_t *buf, size_t size)
> +{
> + uint16_t ip_len;
> +
> + if (((ip6->ip6_ctlun.ip6_un1.ip6_un1_flow & 0xF0) >> 4)
> + != IP_HEADER_VERSION_6) {
> + return RSC_BYPASS;
> + }
> +
> + /* Both option and protocol is checked in this */
> + if (ip6->ip6_ctlun.ip6_un1.ip6_un1_nxt != IPPROTO_TCP) {
> + chain->stat.bypass_not_tcp++;
> + return RSC_BYPASS;
> + }
> +
> + ip_len = htons(ip6->ip6_ctlun.ip6_un1.ip6_un1_plen);
> + if (ip_len < sizeof(struct tcp_header) ||
> + ip_len > (size - chain->n->guest_hdr_len - sizeof(struct eth_header)
> + - sizeof(struct ip6_header))) {
> + chain->stat.ip_hacked++;
> + return RSC_BYPASS;
> + }
> +
> + /* Don't handle packets with ecn flag */
> + if (IP6_ECN(ip6->ip6_ctlun.ip6_un3.ip6_un3_ecn)) {
> + chain->stat.ip_ecn++;
> + return RSC_BYPASS;
> + }
> +
> + return RSC_CANDIDATE;
> +}
> +
> +static size_t virtio_net_rsc_receive6(void *opq, NetClientState* nc,
> + const uint8_t *buf, size_t size)
> +{
> + int32_t ret;
> + uint16_t hdr_len;
> + NetRscChain *chain;
> + NetRscUnit unit;
> +
> + chain = (NetRscChain *)opq;
> + hdr_len = ((VirtIONet *)(chain->n))->guest_hdr_len;
> +
> + if (size < (hdr_len + sizeof(struct eth_header) + sizeof(struct
> ip6_header)
> + + sizeof(tcp_header))) {
> + return virtio_net_do_receive(nc, buf, size);
> + }
> +
> + virtio_net_rsc_extract_unit6(chain, buf, &unit);
> + if (RSC_CANDIDATE != virtio_net_rsc_sanity_check6(chain,
> + unit.ip, buf, size)) {
> + return virtio_net_do_receive(nc, buf, size);
> + }
> +
> + ret = virtio_net_rsc_tcp_ctrl_check(chain, unit.tcp);
> + if (ret == RSC_BYPASS) {
> + return virtio_net_do_receive(nc, buf, size);
> + } else if (ret == RSC_FINAL) {
> + return virtio_net_rsc_drain_flow(chain, nc, buf, size,
> + ((hdr_len + sizeof(struct eth_header)) + 8),
> + VIRTIO_NET_IP6_ADDR_SIZE,
> + hdr_len + sizeof(struct eth_header)
> + + sizeof(struct ip6_header));
> + }
> +
> + return virtio_net_rsc_do_coalesce(chain, nc, buf, size, &unit);
> +}
> +
> +static NetRscChain *virtio_net_rsc_lookup_chain(VirtIONet * n,
> + NetClientState *nc,
> + uint16_t proto)
> +{
> + NetRscChain *chain;
> +
> + if ((proto != (uint16_t)ETH_P_IP) && (proto != (uint16_t)ETH_P_IPV6)) {
> + return NULL;
> + }
> +
> + QTAILQ_FOREACH(chain, &n->rsc_chains, next) {
> + if (chain->proto == proto) {
> + return chain;
> + }
> + }
> +
> + chain = g_malloc(sizeof(*chain));
> + chain->n = n;
> + chain->proto = proto;
> + if (proto == (uint16_t)ETH_P_IP) {
> + chain->max_payload = VIRTIO_NET_MAX_IP4_PAYLOAD;
> + chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
> + } else {
> + chain->max_payload = VIRTIO_NET_MAX_IP6_PAYLOAD;
> + chain->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
> + }
> + chain->drain_timer = timer_new_ns(QEMU_CLOCK_HOST,
> + virtio_net_rsc_purge, chain);
> + memset(&chain->stat, 0, sizeof(chain->stat));
> +
> + QTAILQ_INIT(&chain->buffers);
> + QTAILQ_INSERT_TAIL(&n->rsc_chains, chain, next);
> +
> + return chain;
> +}
> +
> +static ssize_t virtio_net_rsc_receive(NetClientState *nc,
> + const uint8_t *buf,
> + size_t size)
> +{
> + uint16_t proto;
> + NetRscChain *chain;
> + struct eth_header *eth;
> + VirtIONet *n;
> +
> + n = qemu_get_nic_opaque(nc);
> + if (size < (n->host_hdr_len + sizeof(struct eth_header))) {
> + return virtio_net_do_receive(nc, buf, size);
> + }
> +
> + eth = (struct eth_header *)(buf + n->guest_hdr_len);
> + proto = htons(eth->h_proto);
> +
> + chain = virtio_net_rsc_lookup_chain(n, nc, proto);
> + if (chain) {
> + chain->stat.received++;
> + if (proto == (uint16_t)ETH_P_IP && n->rsc4_enabled) {
> + return virtio_net_rsc_receive4(chain, nc, buf, size);
> + } else if (proto == (uint16_t)ETH_P_IPV6 && n->rsc6_enabled) {
> + return virtio_net_rsc_receive6(chain, nc, buf, size);
> + }
> + }
> + return virtio_net_do_receive(nc, buf, size);
> +}
> +
> +static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf,
> + size_t size)
> +{
> + VirtIONet *n = qemu_get_nic_opaque(nc);
> + if ((n->rsc4_enabled || n->rsc6_enabled)) {
> + return virtio_net_rsc_receive(nc, buf, size);
> + } else {
> + return virtio_net_do_receive(nc, buf, size);
> + }
> +}
> +
> static int32_t virtio_net_flush_tx(VirtIONetQueue *q);
>
> static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
> @@ -1342,7 +1974,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
> ssize_t ret;
> unsigned int out_num;
> struct iovec sg[VIRTQUEUE_MAX_SIZE], sg2[VIRTQUEUE_MAX_SIZE + 1],
> *out_sg;
> - struct virtio_net_hdr_mrg_rxbuf mhdr;
> + struct virtio_net_hdr_mrg_rxbuf hdr;
>
> elem = virtqueue_pop(q->tx_vq, sizeof(VirtQueueElement));
> if (!elem) {
> @@ -1359,7 +1991,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
> }
>
> if (n->has_vnet_hdr) {
> - if (iov_to_buf(out_sg, out_num, 0, &mhdr, n->guest_hdr_len) <
> + if (iov_to_buf(out_sg, out_num, 0, &hdr, n->guest_hdr_len) <
> n->guest_hdr_len) {
> virtio_error(vdev, "virtio-net header incorrect");
> virtqueue_detach_element(q->tx_vq, elem, 0);
> @@ -1367,8 +1999,8 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
> return -EINVAL;
> }
> if (n->needs_vnet_hdr_swap) {
> - virtio_net_hdr_swap(vdev, (void *) &mhdr);
> - sg2[0].iov_base = &mhdr;
> + virtio_net_hdr_swap(vdev, (void *) &hdr);
> + sg2[0].iov_base = &hdr;
> sg2[0].iov_len = n->guest_hdr_len;
> out_num = iov_copy(&sg2[1], ARRAY_SIZE(sg2) - 1,
> out_sg, out_num,
> @@ -2075,6 +2707,7 @@ static void virtio_net_device_realize(DeviceState *dev,
> Error **errp)
> nc = qemu_get_queue(n->nic);
> nc->rxfilter_notify_enabled = 1;
>
> + QTAILQ_INIT(&n->rsc_chains);
> n->qdev = dev;
> }
>
> @@ -2104,6 +2737,7 @@ static void virtio_net_device_unrealize(DeviceState
> *dev, Error **errp)
> timer_free(n->announce_timer);
> g_free(n->vqs);
> qemu_del_nic(n->nic);
> + virtio_net_rsc_cleanup(n);
> virtio_cleanup(vdev);
> }
>
> @@ -2184,6 +2818,10 @@ static Property virtio_net_properties[] = {
> DEFINE_PROP_BIT64("ctrl_guest_offloads", VirtIONet, host_features,
> VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, true),
> DEFINE_PROP_BIT64("mq", VirtIONet, host_features, VIRTIO_NET_F_MQ,
> false),
> + DEFINE_PROP_BIT64("guest_rsc_ext", VirtIONet, host_features,
> + VIRTIO_NET_F_RSC_EXT, false),
> + DEFINE_PROP_UINT32("rsc_interval", VirtIONet, rsc_timeout,
> + VIRTIO_NET_RSC_INTERVAL),
what if interval is set without guest_rsc_ext? should init fail?
> DEFINE_NIC_PROPERTIES(VirtIONet, nic_conf),
> DEFINE_PROP_UINT32("x-txtimer", VirtIONet, net_conf.txtimer,
> TX_TIMER_INTERVAL),
> diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h
> index 4d7f3c82ca..0da99dcfa0 100644
> --- a/include/hw/virtio/virtio-net.h
> +++ b/include/hw/virtio/virtio-net.h
> @@ -44,6 +44,83 @@ typedef struct virtio_net_conf
> uint8_t duplex;
> } virtio_net_conf;
>
> +/* Coalesced packets type & status */
> +typedef enum {
> + RSC_COALESCE, /* Data been coalesced */
> + RSC_FINAL, /* Will terminate current connection */
> + RSC_NO_MATCH, /* No matched in the buffer pool */
> + RSC_BYPASS, /* Packet to be bypass, not tcp, tcp ctrl, etc */
> + RSC_CANDIDATE /* Data want to be coalesced */
> +} COALESCE_STATUS;
Should be CoalesceStatus.
> +
> +typedef struct NetRscStat {
> + uint32_t received;
> + uint32_t coalesced;
> + uint32_t over_size;
> + uint32_t cache;
> + uint32_t empty_cache;
> + uint32_t no_match_cache;
> + uint32_t win_update;
> + uint32_t no_match;
> + uint32_t tcp_syn;
> + uint32_t tcp_ctrl_drain;
> + uint32_t dup_ack;
> + uint32_t dup_ack1;
> + uint32_t dup_ack2;
> + uint32_t pure_ack;
> + uint32_t ack_out_of_win;
> + uint32_t data_out_of_win;
> + uint32_t data_out_of_order;
> + uint32_t data_after_pure_ack;
> + uint32_t bypass_not_tcp;
> + uint32_t tcp_option;
> + uint32_t tcp_all_opt;
> + uint32_t ip_frag;
> + uint32_t ip_ecn;
> + uint32_t ip_hacked;
> + uint32_t ip_option;
> + uint32_t purge_failed;
> + uint32_t drain_failed;
> + uint32_t final_failed;
> + int64_t timer;
> +} NetRscStat;
> +
> +/* Rsc unit general info used to checking if can coalescing */
> +typedef struct NetRscUnit {
> + void *ip; /* ip header */
> + uint16_t *ip_plen; /* data len pointer in ip header field */
> + struct tcp_header *tcp; /* tcp header */
> + uint16_t tcp_hdrlen; /* tcp header len */
> + uint16_t payload; /* pure payload without virtio/eth/ip/tcp */
> +} NetRscUnit;
> +
> +/* Coalesced segmant */
> +typedef struct NetRscSeg {
> + QTAILQ_ENTRY(NetRscSeg) next;
> + void *buf;
> + size_t size;
> + uint16_t packets;
> + uint16_t dup_ack;
> + bool is_coalesced; /* need recal ipv4 header checksum, mark here */
> + NetRscUnit unit;
> + NetClientState *nc;
> +} NetRscSeg;
If these structs are generic and not virtio specific,
pls put them and code for handling them in generic files
under net/. OTOH if they are virtio specific, please
prefix names with Virtio.
> +
> +struct VirtIONet;
> +typedef struct VirtIONet VirtIONet;
> +
> +/* Chain is divided by protocol(ipv4/v6) and NetClientInfo */
> +typedef struct NetRscChain {
> + QTAILQ_ENTRY(NetRscChain) next;
> + VirtIONet *n; /* VirtIONet */
> + uint16_t proto;
> + uint8_t gso_type;
> + uint16_t max_payload;
> + QEMUTimer *drain_timer;
> + QTAILQ_HEAD(, NetRscSeg) buffers;
> + NetRscStat stat;
> +} NetRscChain;
> +
> /* Maximum packet size we can receive from tap device: header + 64k */
> #define VIRTIO_NET_MAX_BUFSIZE (sizeof(struct virtio_net_hdr) + (64 * KiB))
>
> @@ -66,12 +143,16 @@ typedef struct VirtIONet {
> VirtIONetQueue *vqs;
> VirtQueue *ctrl_vq;
> NICState *nic;
> + QTAILQ_HEAD(, NetRscChain) rsc_chains;
what exactly happens with these chains on migration?
> uint32_t tx_timeout;
> int32_t tx_burst;
> uint32_t has_vnet_hdr;
> size_t host_hdr_len;
> size_t guest_hdr_len;
> uint64_t host_features;
> + uint32_t rsc_timeout;
> + uint8_t rsc4_enabled;
> + uint8_t rsc6_enabled;
> uint8_t has_ufo;
> uint32_t mergeable_rx_bufs;
> uint8_t promisc;
> diff --git a/include/net/eth.h b/include/net/eth.h
> index e6dc8a7ba0..7f45c678e7 100644
> --- a/include/net/eth.h
> +++ b/include/net/eth.h
> @@ -177,6 +177,8 @@ struct tcp_hdr {
> #define TH_PUSH 0x08
> #define TH_ACK 0x10
> #define TH_URG 0x20
> +#define TH_ECE 0x40
> +#define TH_CWR 0x80
> u_short th_win; /* window */
> u_short th_sum; /* checksum */
> u_short th_urp; /* urgent pointer */
> diff --git a/include/standard-headers/linux/virtio_net.h
> b/include/standard-headers/linux/virtio_net.h
> index 260c3681d7..0d8658c06a 100644
> --- a/include/standard-headers/linux/virtio_net.h
> +++ b/include/standard-headers/linux/virtio_net.h
> @@ -57,6 +57,10 @@
> * Steering */
> #define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */
>
> +#define VIRTIO_NET_F_RSC_EXT 38
Should it be VIRTIO_NET_F_GUEST_RSC_EXT ?
> +#define VIRTIO_NET_F_GUEST_RSC4_DONT_USE 41 /* reserved */
> +#define VIRTIO_NET_F_GUEST_RSC6_DONT_USE 42 /* reserved */
> +
> #define VIRTIO_NET_F_STANDBY 62 /* Act as standby for another device
> * with the same MAC.
> */
> @@ -104,6 +108,7 @@ struct virtio_net_config {
> struct virtio_net_hdr_v1 {
> #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 /* Use csum_start, csum_offset
> */
> #define VIRTIO_NET_HDR_F_DATA_VALID 2 /* Csum is valid */
> +#define VIRTIO_NET_HDR_F_RSC_INFO 4 /* rsc_ext data in csum_ fields
> */
> uint8_t flags;
> #define VIRTIO_NET_HDR_GSO_NONE 0 /* Not a GSO frame */
> #define VIRTIO_NET_HDR_GSO_TCPV4 1 /* GSO frame, IPv4 TCP (TSO) */
> @@ -118,6 +123,9 @@ struct virtio_net_hdr_v1 {
> __virtio16 num_buffers; /* Number of merged rx buffers */
> };
>
> +#define rsc_ext_num_packets csum_start
> +#define rsc_ext_num_dupacks csum_offset
I would prefer an inline function to set the field, or a union.
> +
> #ifndef VIRTIO_NET_NO_LEGACY
> /* This header comes first in the scatter-gather list.
> * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must
This part needs to get into the Linux header. Pls post there.
Until it does you can put it in virtio-net.c
> --
> 2.17.1
