anyone?
On Fri, Jun 23, 2023 at 06:06:16PM +0200, Alexander Bluhm wrote:
> Hi,
>
> Claudio@ mentioned the idea to use TSO and LRO on the loopback
> interface to transfer TCP faster.
>
> I see a performance effect with this diff, but more importantly it
> gives us more test coverage. Currently LRO on lo(4) is default
> off.
>
> Future plan is:
> - Fix some corner cases for LRO/TSO with TCP path-MTU discovery
> and IP forwarding when LRO is enabled.
> - Enable LRO/TSO for lo(4) and ix(4) per default.
> - Jan@ commits his ixl(4) TSO diff.
>
> ok for lo(4) LRO/TSO with default off?
>
> bluhm
>
> Index: sys/net/if.c
> ===================================================================
> RCS file: /data/mirror/openbsd/cvs/src/sys/net/if.c,v
> retrieving revision 1.700
> diff -u -p -r1.700 if.c
> --- sys/net/if.c 12 Jun 2023 21:19:54 -0000 1.700
> +++ sys/net/if.c 23 Jun 2023 15:48:27 -0000
> @@ -106,6 +106,9 @@
> #ifdef MROUTING
> #include <netinet/ip_mroute.h>
> #endif
> +#include <netinet/tcp.h>
> +#include <netinet/tcp_timer.h>
> +#include <netinet/tcp_var.h>
>
> #ifdef INET6
> #include <netinet6/in6_var.h>
> @@ -802,12 +805,29 @@ if_input_local(struct ifnet *ifp, struct
> * is now incorrect, will be calculated before sending.
> */
> keepcksum = m->m_pkthdr.csum_flags & (M_IPV4_CSUM_OUT |
> - M_TCP_CSUM_OUT | M_UDP_CSUM_OUT | M_ICMP_CSUM_OUT);
> + M_TCP_CSUM_OUT | M_UDP_CSUM_OUT | M_ICMP_CSUM_OUT |
> + M_TCP_TSO);
> m_resethdr(m);
> m->m_flags |= M_LOOP | keepflags;
> m->m_pkthdr.csum_flags = keepcksum;
> m->m_pkthdr.ph_ifidx = ifp->if_index;
> m->m_pkthdr.ph_rtableid = ifp->if_rdomain;
> +
> + if (ISSET(keepcksum, M_TCP_TSO) && m->m_pkthdr.len > ifp->if_mtu) {
> + if (ifp->if_mtu > 0 &&
> + ((af == AF_INET &&
> + ISSET(ifp->if_capabilities, IFCAP_TSOv4)) ||
> + (af == AF_INET6 &&
> + ISSET(ifp->if_capabilities, IFCAP_TSOv6)))) {
> + tcpstat_inc(tcps_inswlro);
> + tcpstat_add(tcps_inpktlro,
> + (m->m_pkthdr.len + ifp->if_mtu - 1) / ifp->if_mtu);
> + } else {
> + tcpstat_inc(tcps_inbadlro);
> + m_freem(m);
> + return (EPROTONOSUPPORT);
> + }
> + }
>
> if (ISSET(keepcksum, M_TCP_CSUM_OUT))
> m->m_pkthdr.csum_flags |= M_TCP_CSUM_IN_OK;
> Index: sys/net/if_loop.c
> ===================================================================
> RCS file: /data/mirror/openbsd/cvs/src/sys/net/if_loop.c,v
> retrieving revision 1.94
> diff -u -p -r1.94 if_loop.c
> --- sys/net/if_loop.c 5 Jun 2023 11:35:46 -0000 1.94
> +++ sys/net/if_loop.c 23 Jun 2023 15:48:27 -0000
> @@ -175,7 +175,8 @@ loop_clone_create(struct if_clone *ifc,
> ifp->if_xflags = IFXF_CLONED;
> ifp->if_capabilities = IFCAP_CSUM_IPv4 |
> IFCAP_CSUM_TCPv4 | IFCAP_CSUM_UDPv4 |
> - IFCAP_CSUM_TCPv6 | IFCAP_CSUM_UDPv6;
> + IFCAP_CSUM_TCPv6 | IFCAP_CSUM_UDPv6 |
> + IFCAP_LRO;
> ifp->if_rtrequest = lortrequest;
> ifp->if_ioctl = loioctl;
> ifp->if_input = loinput;
> @@ -281,6 +282,10 @@ loioctl(struct ifnet *ifp, u_long cmd, c
>
> switch (cmd) {
> case SIOCSIFFLAGS:
> + if (ISSET(ifp->if_xflags, IFXF_LRO))
> + SET(ifp->if_capabilities, IFCAP_TSOv4 | IFCAP_TSOv6);
> + else
> + CLR(ifp->if_capabilities, IFCAP_TSOv4 | IFCAP_TSOv6);
> break;
>
> case SIOCSIFADDR:
> Index: sys/netinet/tcp_usrreq.c
> ===================================================================
> RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/tcp_usrreq.c,v
> retrieving revision 1.219
> diff -u -p -r1.219 tcp_usrreq.c
> --- sys/netinet/tcp_usrreq.c 23 May 2023 09:16:16 -0000 1.219
> +++ sys/netinet/tcp_usrreq.c 23 Jun 2023 15:48:27 -0000
> @@ -1340,6 +1340,7 @@ tcp_sysctl_tcpstat(void *oldp, size_t *o
> ASSIGN(tcps_outhwtso);
> ASSIGN(tcps_outpkttso);
> ASSIGN(tcps_outbadtso);
> + ASSIGN(tcps_inswlro);
> ASSIGN(tcps_inhwlro);
> ASSIGN(tcps_inpktlro);
> ASSIGN(tcps_inbadlro);
> Index: sys/netinet/tcp_var.h
> ===================================================================
> RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/tcp_var.h,v
> retrieving revision 1.167
> diff -u -p -r1.167 tcp_var.h
> --- sys/netinet/tcp_var.h 23 May 2023 09:16:16 -0000 1.167
> +++ sys/netinet/tcp_var.h 23 Jun 2023 15:48:27 -0000
> @@ -447,6 +447,7 @@ struct tcpstat {
> u_int32_t tcps_outhwtso; /* output tso processed by hardware */
> u_int32_t tcps_outpkttso; /* packets generated by tso */
> u_int32_t tcps_outbadtso; /* output tso failed, packet dropped */
> + u_int32_t tcps_inswlro; /* input lro on pseudo device */
> u_int32_t tcps_inhwlro; /* input lro from hardware */
> u_int32_t tcps_inpktlro; /* packets coalesced by hardware lro */
> u_int32_t tcps_inbadlro; /* input bad lro packets */
> @@ -628,6 +629,7 @@ enum tcpstat_counters {
> tcps_outhwtso,
> tcps_outpkttso,
> tcps_outbadtso,
> + tcps_inswlro,
> tcps_inhwlro,
> tcps_inpktlro,
> tcps_inbadlro,
> Index: usr.bin/netstat/inet.c
> ===================================================================
> RCS file: /data/mirror/openbsd/cvs/src/usr.bin/netstat/inet.c,v
> retrieving revision 1.176
> diff -u -p -r1.176 inet.c
> --- usr.bin/netstat/inet.c 23 May 2023 09:16:16 -0000 1.176
> +++ usr.bin/netstat/inet.c 23 Jun 2023 15:55:55 -0000
> @@ -439,9 +439,12 @@ tcp_stats(char *name)
> p(tcps_inswcsum, "\t\t%u packet%s software-checksummed\n");
> p(tcps_rcvbadsig, "\t\t%u bad/missing md5 checksum%s\n");
> p(tcps_rcvgoodsig, "\t\t%llu good md5 checksum%s\n");
> + p(tcps_inswlro,
> + "\t\t%u input LRO packet%s passed through pseudo device\n");
> p(tcps_inhwlro, "\t\t%u input LRO generated packet%s from hardware\n");
> - p(tcps_inpktlro, "\t\t%u input LRO coalesced packet%s by hardware\n");
> - p(tcps_inbadlro, "\t\t%u input bad LRO packet%s\n");
> + p(tcps_inpktlro,
> + "\t\t%u input LRO coalesced packet%s by network device\n");
> + p(tcps_inbadlro, "\t\t%u input bad LRO packet%s dropped\n");
> p(tcps_connattempt, "\t%u connection request%s\n");
> p(tcps_accepts, "\t%u connection accept%s\n");
> p(tcps_connects, "\t%u connection%s established (including accepts)\n");
