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--- sys/net/if.c.orig
+++ sys/net/if.c
@@ -62,6 +62,8 @@
#include <sys/domain.h>
#include <sys/jail.h>
#include <sys/priv.h>
+#include <sys/sched.h>
+#include <sys/smp.h>
#include <machine/stdarg.h>
#include <vm/uma.h>
@@ -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
|
