From 1917ef996d1b6aa6232992bf93d6f7c6b477235f Mon Sep 17 00:00:00 2001
From: Oleg Bulyzhin <oleg@FreeBSD.org>
Date: Mon, 15 Jun 2009 17:14:47 +0000
Subject: [PATCH] Since dn_pipe.numbytes is int64_t now - remove unnecessary
 overflow detection code in ready_event_wfq().

---
 sys/netinet/ipfw/ip_dummynet.c | 28 +++++++---------------------
 1 file changed, 7 insertions(+), 21 deletions(-)

diff --git a/sys/netinet/ipfw/ip_dummynet.c b/sys/netinet/ipfw/ip_dummynet.c
index d237433f0f30..bf54839ec7fa 100644
--- a/sys/netinet/ipfw/ip_dummynet.c
+++ b/sys/netinet/ipfw/ip_dummynet.c
@@ -56,7 +56,6 @@ __FBSDID("$FreeBSD$");
  * include files marked with XXX are probably not needed
  */
 
-#include <sys/limits.h>
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/malloc.h>
@@ -686,16 +685,11 @@ ready_event_wfq(struct dn_pipe *p, struct mbuf **head, struct mbuf **tail)
 	int p_was_empty = (p->head == NULL);
 	struct dn_heap *sch = &(p->scheduler_heap);
 	struct dn_heap *neh = &(p->not_eligible_heap);
-	int64_t p_numbytes = p->numbytes;
 
 	DUMMYNET_LOCK_ASSERT();
 
 	if (p->if_name[0] == 0)		/* tx clock is simulated */
-		/*
-		 * Since result may not fit into p->numbytes (32bit) we
-		 * are using 64bit var here.
-		 */
-		p_numbytes += (curr_time - p->sched_time) * p->bandwidth;
+		p->numbytes += (curr_time - p->sched_time) * p->bandwidth;
 	else {	/*
 		 * tx clock is for real,
 		 * the ifq must be empty or this is a NOP.
@@ -712,7 +706,7 @@ ready_event_wfq(struct dn_pipe *p, struct mbuf **head, struct mbuf **tail)
 	 * While we have backlogged traffic AND credit, we need to do
 	 * something on the queue.
 	 */
-	while (p_numbytes >= 0 && (sch->elements > 0 || neh->elements > 0)) {
+	while (p->numbytes >= 0 && (sch->elements > 0 || neh->elements > 0)) {
 		if (sch->elements > 0) {
 			/* Have some eligible pkts to send out. */
 			struct dn_flow_queue *q = sch->p[0].object;
@@ -722,7 +716,7 @@ ready_event_wfq(struct dn_pipe *p, struct mbuf **head, struct mbuf **tail)
 			int len_scaled = p->bandwidth ? len * 8 * hz : 0;
 
 			heap_extract(sch, NULL); /* Remove queue from heap. */
-			p_numbytes -= len_scaled;
+			p->numbytes -= len_scaled;
 			move_pkt(pkt, q, p, len);
 
 			p->V += (len << MY_M) / p->sum;	/* Update V. */
@@ -763,11 +757,11 @@ ready_event_wfq(struct dn_pipe *p, struct mbuf **head, struct mbuf **tail)
 		}
 
 		if (p->if_name[0] != '\0') { /* Tx clock is from a real thing */
-			p_numbytes = -1;	/* Mark not ready for I/O. */
+			p->numbytes = -1;	/* Mark not ready for I/O. */
 			break;
 		}
 	}
-	if (sch->elements == 0 && neh->elements == 0 && p_numbytes >= 0 &&
+	if (sch->elements == 0 && neh->elements == 0 && p->numbytes >= 0 &&
 	    p->idle_heap.elements > 0) {
 		/*
 		 * No traffic and no events scheduled.
@@ -790,11 +784,11 @@ ready_event_wfq(struct dn_pipe *p, struct mbuf **head, struct mbuf **tail)
 	 * If we are under credit, schedule the next ready event.
 	 * Also fix the delivery time of the last packet.
 	 */
-	if (p->if_name[0]==0 && p_numbytes < 0) { /* This implies bw > 0. */
+	if (p->if_name[0]==0 && p->numbytes < 0) { /* This implies bw > 0. */
 		dn_key t = 0;		/* Number of ticks i have to wait. */
 
 		if (p->bandwidth > 0)
-			t = (p->bandwidth - 1 - p_numbytes) / p->bandwidth;
+			t = (p->bandwidth - 1 - p->numbytes) / p->bandwidth;
 		dn_tag_get(p->tail)->output_time += t;
 		p->sched_time = curr_time;
 		heap_insert(&wfq_ready_heap, curr_time + t, (void *)p);
@@ -804,14 +798,6 @@ ready_event_wfq(struct dn_pipe *p, struct mbuf **head, struct mbuf **tail)
 		 */
 	}
 
-	/* Fit (adjust if necessary) 64bit result into 32bit variable. */
-	if (p_numbytes > INT_MAX)
-		p->numbytes = INT_MAX;
-	else if (p_numbytes < INT_MIN)
-		p->numbytes = INT_MIN;
-	else
-		p->numbytes = p_numbytes;
-
 	/*
 	 * If the delay line was empty call transmit_event() now.
 	 * Otherwise, the scheduler will take care of it.