On Tue, Jun 23, 2015 at 03:01:54PM +0200, Martin Pieuchot wrote:
> When an interface is detached or destroyed the CPU executing if_detach()
> removes all the mbufs received by this interface on three queues:
> ARP, IPv4 and IPv6 protocol queues.
>
> This made sense to avoid referencing a dangling "rcvif" pointer. But now
> mbufs contain unique interface indexes and protocol interrupt routines
> handle just fine the case where if_get() returns a NULL pointer.
>
> So I'd like to get rid of this explicit garbage collection. Note that
> this will leave mbufs on the protocol queues until the next netisr is
> executed for the corresponding queue. This is a functional change but
> I don't think it's a problem. It only matters if you destroy your only
> pseudo interface or unplug your single USB interface without replugging
> it.
>
> Comments, oks?
OK claudio@ (there are many more queues that would need to be cleaned if
we wanted this)
> Index: net/if.c
> ===
> RCS file: /cvs/src/sys/net/if.c,v
> retrieving revision 1.341
> diff -u -p -r1.341 if.c
> --- net/if.c 23 Jun 2015 09:42:23 - 1.341
> +++ net/if.c 23 Jun 2015 10:54:04 -
> @@ -128,8 +128,6 @@ void if_attachsetup(struct ifnet *);
> void if_attachdomain1(struct ifnet *);
> void if_attach_common(struct ifnet *);
>
> -int if_detach_filter(void *, const struct mbuf *);
> -void if_detach_queues(struct ifnet *, struct niqueue *);
> void if_detached_start(struct ifnet *);
> int if_detached_ioctl(struct ifnet *, u_long, caddr_t);
>
> @@ -644,23 +642,6 @@ if_detach(struct ifnet *ifp)
> pfi_detach_ifnet(ifp);
> #endif
>
> - /*
> - * remove packets came from ifp, from software interrupt queues.
> - * net/netisr_dispatch.h is not usable, as some of them use
> - * strange queue names.
> - */
> -#define IF_DETACH_QUEUES(x) \
> -do { \
> - extern struct niqueue x; \
> - if_detach_queues(ifp, & x); \
> -} while (0)
> - IF_DETACH_QUEUES(arpintrq);
> - IF_DETACH_QUEUES(ipintrq);
> -#ifdef INET6
> - IF_DETACH_QUEUES(ip6intrq);
> -#endif
> -#undef IF_DETACH_QUEUES
> -
> /* Remove the interface from the list of all interfaces. */
> TAILQ_REMOVE(&ifnet, ifp, if_list);
> if (ISSET(ifp->if_xflags, IFXF_TXREADY))
> @@ -701,34 +682,6 @@ do { \
>
> ifindex2ifnet[ifp->if_index] = NULL;
> splx(s);
> -}
> -
> -int
> -if_detach_filter(void *ctx, const struct mbuf *m)
> -{
> - struct ifnet *ifp = ctx;
> -
> -#ifdef DIAGNOSTIC
> - if ((m->m_flags & M_PKTHDR) == 0)
> - return (0);
> -#endif
> -
> - return (m->m_pkthdr.ph_ifidx == ifp->if_index);
> -}
> -
> -void
> -if_detach_queues(struct ifnet *ifp, struct niqueue *niq)
> -{
> - struct mbuf *m0, *m;
> -
> - m0 = niq_filter(niq, if_detach_filter, ifp);
> - while (m0 != NULL) {
> - m = m0;
> - m0 = m->m_nextpkt;
> -
> - m->m_nextpkt = NULL;
> - m_freem(m);
> - }
> }
>
> /*
>
--
:wq Claudio
