Index: if.c
===================================================================
RCS file: /cvs/src/sys/net/if.c,v
retrieving revision 1.572
diff -u -p -r1.572 if.c
--- if.c	26 Feb 2019 03:20:08 -0000	1.572
+++ if.c	27 Feb 2019 12:05:06 -0000
@@ -738,7 +738,7 @@ if_enqueue_ifq(struct ifnet *ifp, struct
 void
 if_input(struct ifnet *ifp, struct mbuf_list *ml)
 {
-	ifiq_input(&ifp->if_rcv, ml, 2048);
+	ifiq_input(&ifp->if_rcv, ml);
 }
 
 int
Index: ifq.c
===================================================================
RCS file: /cvs/src/sys/net/ifq.c,v
retrieving revision 1.25
diff -u -p -r1.25 ifq.c
--- ifq.c	16 Dec 2018 03:36:02 -0000	1.25
+++ ifq.c	27 Feb 2019 12:05:06 -0000
@@ -445,6 +445,7 @@ ifiq_init(struct ifiqueue *ifiq, struct 
 	mtx_init(&ifiq->ifiq_mtx, IPL_NET);
 	ml_init(&ifiq->ifiq_ml);
 	task_set(&ifiq->ifiq_task, ifiq_process, ifiq);
+	ifiq->ifiq_pressure = 0;
 
 	ifiq->ifiq_qdrops = 0;
 	ifiq->ifiq_packets = 0;
@@ -467,17 +468,20 @@ ifiq_destroy(struct ifiqueue *ifiq)
 	ml_purge(&ifiq->ifiq_ml);
 }
 
+unsigned int ifiq_pressure_drop = 16;
+unsigned int ifiq_pressure_return = 2;
+
 int
-ifiq_input(struct ifiqueue *ifiq, struct mbuf_list *ml, unsigned int cwm)
+ifiq_input(struct ifiqueue *ifiq, struct mbuf_list *ml)
 {
 	struct ifnet *ifp = ifiq->ifiq_if;
 	struct mbuf *m;
 	uint64_t packets;
 	uint64_t bytes = 0;
+	unsigned int pressure;
 #if NBPFILTER > 0
 	caddr_t if_bpf;
 #endif
-	int rv = 1;
 
 	if (ml_empty(ml))
 		return (0);
@@ -518,12 +522,11 @@ ifiq_input(struct ifiqueue *ifiq, struct
 	ifiq->ifiq_packets += packets;
 	ifiq->ifiq_bytes += bytes;
 
-	if (ifiq_len(ifiq) >= cwm * 5)
+	pressure = ++ifiq->ifiq_pressure;
+	if (pressure > ifiq_pressure_drop)
 		ifiq->ifiq_qdrops += ml_len(ml);
-	else {
-		rv = (ifiq_len(ifiq) >= cwm * 3);
+	else
 		ml_enlist(&ifiq->ifiq_ml, ml);
-	}
 	mtx_leave(&ifiq->ifiq_mtx);
 
 	if (ml_empty(ml))
@@ -531,7 +534,7 @@ ifiq_input(struct ifiqueue *ifiq, struct
 	else
 		ml_purge(ml);
 
-	return (rv);
+	return (pressure > ifiq_pressure_return);
 }
 
 void
@@ -573,6 +576,7 @@ ifiq_process(void *arg)
 		return;
 
 	mtx_enter(&ifiq->ifiq_mtx);
+	ifiq->ifiq_pressure = 0;
 	ml = ifiq->ifiq_ml;
 	ml_init(&ifiq->ifiq_ml);
 	mtx_leave(&ifiq->ifiq_mtx);
Index: ifq.h
===================================================================
RCS file: /cvs/src/sys/net/ifq.h,v
retrieving revision 1.22
diff -u -p -r1.22 ifq.h
--- ifq.h	11 Dec 2018 01:36:42 -0000	1.22
+++ ifq.h	27 Feb 2019 12:05:06 -0000
@@ -80,6 +80,7 @@ struct ifiqueue {
 	struct mutex		 ifiq_mtx;
 	struct mbuf_list	 ifiq_ml;
 	struct task		 ifiq_task;
+	unsigned int		 ifiq_pressure;
 
 	/* counters */
 	uint64_t		 ifiq_packets;
@@ -473,8 +474,7 @@ ifq_idx(struct ifqueue *ifq, unsigned in
 
 void		 ifiq_init(struct ifiqueue *, struct ifnet *, unsigned int);
 void		 ifiq_destroy(struct ifiqueue *);
-int		 ifiq_input(struct ifiqueue *, struct mbuf_list *,
-		     unsigned int);
+int		 ifiq_input(struct ifiqueue *, struct mbuf_list *);
 int		 ifiq_enqueue(struct ifiqueue *, struct mbuf *);
 void		 ifiq_add_data(struct ifiqueue *, struct if_data *);
 void		 ifiq_barrier(struct ifiqueue *);