No one interested in this one? I have another bridge speedup diff after
this.
On Fri, 28 Oct 2011, Camiel Dobbelaar wrote:
> M_PROTO1 is used by if_bridge on the input path. On the output path it's
> used now only by if_bridge for if_gif. I think we can use it generically
> to mark packets as "processed by bridge" in the output path.
>
> The diff simplifies things and avoids mtag checking and allocation so is
> more efficient too.
>
> The old code checks if a packet has passed the _same_ bridge already, but
> as an interface can only be a member of one bridge I think the flag is
> sufficient.
>
> It looks like the only other user of M_PROTO1 is netbt/hci_link.c, but
> that can be fixed if the diff is acceptable otherwise.
>
> Tested lightly in a bridge/gif setup, but could use some more testing.
> (especially with ipsec in the mix too)
>
>
> Index: if_bridge.c
> ===================================================================
> RCS file: /cvs/src/sys/net/if_bridge.c,v
> retrieving revision 1.193
> diff -u -p -r1.193 if_bridge.c
> --- if_bridge.c 4 Jul 2011 06:54:49 -0000 1.193
> +++ if_bridge.c 28 Oct 2011 17:55:04 -0000
> @@ -2813,9 +2813,8 @@ bridge_ifenqueue(struct bridge_softc *sc
> #if NGIF > 0
> /* Packet needs etherip encapsulation. */
> if (ifp->if_type == IFT_GIF) {
> - m->m_flags |= M_PROTO1;
> -
> /* Count packets input into the gif from outside */
> + /* XXX do this in if_gif? */
> ifp->if_ipackets++;
> ifp->if_ibytes += m->m_pkthdr.len;
> }
> @@ -2844,6 +2843,7 @@ bridge_ifenqueue(struct bridge_softc *sc
> }
> #endif
> len = m->m_pkthdr.len;
> + m->m_flags |= M_PROTO1;
> mflags = m->m_flags;
> IFQ_ENQUEUE(&ifp->if_snd, m, NULL, error);
> if (error) {
> Index: if_ethersubr.c
> ===================================================================
> RCS file: /cvs/src/sys/net/if_ethersubr.c,v
> retrieving revision 1.151
> diff -u -p -r1.151 if_ethersubr.c
> --- if_ethersubr.c 9 Jul 2011 00:47:18 -0000 1.151
> +++ if_ethersubr.c 28 Oct 2011 17:55:04 -0000
> @@ -382,40 +382,8 @@ ether_output(ifp0, m0, dst, rt0)
> * Interfaces that are bridge members need special handling
> * for output.
> */
> - if (ifp->if_bridge) {
> - struct m_tag *mtag;
> -
> - /*
> - * Check if this packet has already been sent out through
> - * this bridge, in which case we simply send it out
> - * without further bridge processing.
> - */
> - for (mtag = m_tag_find(m, PACKET_TAG_BRIDGE, NULL); mtag;
> - mtag = m_tag_find(m, PACKET_TAG_BRIDGE, mtag)) {
> -#ifdef DEBUG
> - /* Check that the information is there */
> - if (mtag->m_tag_len != sizeof(caddr_t)) {
> - error = EINVAL;
> - goto bad;
> - }
> -#endif
> - if (!bcmp(&ifp->if_bridge, mtag + 1, sizeof(caddr_t)))
> - break;
> - }
> - if (mtag == NULL) {
> - /* Attach a tag so we can detect loops */
> - mtag = m_tag_get(PACKET_TAG_BRIDGE, sizeof(caddr_t),
> - M_NOWAIT);
> - if (mtag == NULL) {
> - error = ENOBUFS;
> - goto bad;
> - }
> - bcopy(&ifp->if_bridge, mtag + 1, sizeof(caddr_t));
> - m_tag_prepend(m, mtag);
> - error = bridge_output(ifp, m, NULL, NULL);
> - return (error);
> - }
> - }
> + if (ifp->if_bridge && !(m->m_flags & M_PROTO1))
> + return (bridge_output(ifp, m, NULL, NULL));
> #endif
> mflags = m->m_flags;
> len = m->m_pkthdr.len;
