--- sys/net/if.c.orig +++ sys/net/if.c @@ -62,6 +62,8 @@ #include #include #include +#include +#include #include #include @@ -1755,6 +1757,30 @@ ifd->ifi_noproto = ifp->if_get_counter(ifp, IFCOUNTER_NOPROTO); } +struct ifnet_read_lock { + struct mtx mtx; /* lock protecting tracker below */ + struct epoch_tracker et; +}; + +DPCPU_DEFINE_STATIC(struct ifnet_read_lock, ifnet_addr_read_lock); +DPCPU_DEFINE_STATIC(struct ifnet_read_lock, ifnet_maddr_read_lock); + +static void +ifnet_read_lock_init(void __unused *arg) +{ + struct ifnet_read_lock *pifrl; + int cpu; + + CPU_FOREACH(cpu) { + pifrl = DPCPU_ID_PTR(cpu, ifnet_addr_read_lock); + mtx_init(&pifrl->mtx, "ifnet_addr_read_lock", NULL, MTX_DEF); + + pifrl = DPCPU_ID_PTR(cpu, ifnet_maddr_read_lock); + mtx_init(&pifrl->mtx, "ifnet_maddr_read_lock", NULL, MTX_DEF); + } +} +SYSINIT(ifnet_read_lock_init, SI_SUB_CPU + 1, SI_ORDER_FIRST, &ifnet_read_lock_init, NULL); + /* * Wrapper functions for struct ifnet address list locking macros. These are * used by kernel modules to avoid encoding programming interface or binary @@ -1764,35 +1790,47 @@ void if_addr_rlock(struct ifnet *ifp) { - MPASS(*(uint64_t *)&ifp->if_addr_et == 0); - epoch_enter_preempt(net_epoch_preempt, &ifp->if_addr_et); + struct ifnet_read_lock *pifrl; + + sched_pin(); + pifrl = DPCPU_PTR(ifnet_addr_read_lock); + mtx_lock(&pifrl->mtx); + epoch_enter_preempt(net_epoch_preempt, &pifrl->et); } void if_addr_runlock(struct ifnet *ifp) { - epoch_exit_preempt(net_epoch_preempt, &ifp->if_addr_et); -#ifdef INVARIANTS - bzero(&ifp->if_addr_et, sizeof(struct epoch_tracker)); -#endif + struct ifnet_read_lock *pifrl; + + pifrl = DPCPU_PTR(ifnet_addr_read_lock); + + epoch_exit_preempt(net_epoch_preempt, &pifrl->et); + mtx_unlock(&pifrl->mtx); + sched_unpin(); } void if_maddr_rlock(if_t ifp) { + struct ifnet_read_lock *pifrl; - MPASS(*(uint64_t *)&ifp->if_maddr_et == 0); - epoch_enter_preempt(net_epoch_preempt, &ifp->if_maddr_et); + sched_pin(); + pifrl = DPCPU_PTR(ifnet_maddr_read_lock); + mtx_lock(&pifrl->mtx); + epoch_enter_preempt(net_epoch_preempt, &pifrl->et); } void if_maddr_runlock(if_t ifp) { + struct ifnet_read_lock *pifrl; - epoch_exit_preempt(net_epoch_preempt, &ifp->if_maddr_et); -#ifdef INVARIANTS - bzero(&ifp->if_maddr_et, sizeof(struct epoch_tracker)); -#endif + pifrl = DPCPU_PTR(ifnet_maddr_read_lock); + + epoch_exit_preempt(net_epoch_preempt, &pifrl->et); + mtx_unlock(&pifrl->mtx); + sched_unpin(); } /* --- sys/net/if_var.h.orig +++ sys/net/if_var.h @@ -381,8 +381,7 @@ */ struct netdump_methods *if_netdump_methods; struct epoch_context if_epoch_ctx; - struct epoch_tracker if_addr_et; - struct epoch_tracker if_maddr_et; + void *if_unused[4]; /* * Spare fields to be added before branching a stable branch, so