From owner-p4-projects@FreeBSD.ORG  Mon Nov 29 22:00:54 2004
Return-Path: <owner-p4-projects@FreeBSD.ORG>
Delivered-To: p4-projects@freebsd.org
Received: by hub.freebsd.org (Postfix, from userid 32767)
	id C111116A4DC; Mon, 29 Nov 2004 22:00:53 +0000 (GMT)
Delivered-To: perforce@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 8F4C516A4D6
	for <perforce@freebsd.org>; Mon, 29 Nov 2004 22:00:53 +0000 (GMT)
Received: from repoman.freebsd.org (repoman.freebsd.org [216.136.204.115])
	by mx1.FreeBSD.org (Postfix) with ESMTP id B971643D48
	for <perforce@freebsd.org>; Mon, 29 Nov 2004 22:00:27 +0000 (GMT)
	(envelope-from peter@freebsd.org)
Received: from repoman.freebsd.org (localhost [127.0.0.1])
	by repoman.freebsd.org (8.13.1/8.13.1) with ESMTP id iATM0REE035147
	for <perforce@freebsd.org>; Mon, 29 Nov 2004 22:00:27 GMT
	(envelope-from peter@freebsd.org)
Received: (from perforce@localhost)
	by repoman.freebsd.org (8.13.1/8.13.1/Submit) id iATM0Rpd035144
	for perforce@freebsd.org; Mon, 29 Nov 2004 22:00:27 GMT
	(envelope-from peter@freebsd.org)
Date: Mon, 29 Nov 2004 22:00:27 GMT
Message-Id: <200411292200.iATM0Rpd035144@repoman.freebsd.org>
X-Authentication-Warning: repoman.freebsd.org: perforce set sender to
	peter@freebsd.org using -f
From: Peter Wemm <peter@FreeBSD.org>
To: Perforce Change Reviews <perforce@freebsd.org>
Subject: PERFORCE change 66061 for review
X-BeenThere: p4-projects@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: p4 projects tree changes <p4-projects.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/p4-projects>,
	<mailto:p4-projects-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/p4-projects>
List-Post: <mailto:p4-projects@freebsd.org>
List-Help: <mailto:p4-projects-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/p4-projects>,
	<mailto:p4-projects-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 29 Nov 2004 22:00:54 -0000

http://perforce.freebsd.org/chv.cgi?CH=66061

Change 66061 by peter@peter_daintree on 2004/11/29 21:59:55

	try and do the rounding properly.

Affected files ...

.. //depot/projects/hammer/sys/kern/tty.c#36 edit

Differences ...

==== //depot/projects/hammer/sys/kern/tty.c#36 (text+ko) ====

@@ -1855,21 +1855,15 @@
 		/*
 		 * Rounding down may make us wake up just short
 		 * of the target, so we round up.
-		 * The formula is ceiling(slp * hz/1000000).
-		 * 32-bit arithmetic is enough for hz < 169.
-		 * XXX see tvtohz() for how to avoid overflow if hz
-		 * is large (divide by `tick' and/or arrange to
-		 * use tvtohz() if hz is large).
 		 */
-		if ((sizeof(u_long) > 4) || hz < 169)
-			slp = (long) (((u_long)slp * hz) + 999999) / 1000000;
-		else {
-			struct timeval tv;
-
-			tv.tv_sec = slp;
-			tv.tv_usec = 0;
-			slp = tvtohz(&tv);
-		}
+		if (slp <= LONG_MAX / 1000000)
+			slp = (slp * 1000000 + (tick - 1)) / tick + 1;
+		else if (slp <= LONG_MAX / hz)
+			slp = slp * hz + 1;
+		else
+			slp = LONG_MAX;
+		if (slp > INT_MAX)
+			slp = INT_MAX;
 		goto sleep;
 	}
 	if (qp->c_cc <= 0) {