From owner-cvs-all@FreeBSD.ORG Mon Mar 12 20:03:54 2007 Return-Path: X-Original-To: cvs-all@freebsd.org Delivered-To: cvs-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 060CE16A403; Mon, 12 Mar 2007 20:03:54 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (arm132.internetdsl.tpnet.pl [83.17.198.132]) by mx1.freebsd.org (Postfix) with ESMTP id 8359A13C480; Mon, 12 Mar 2007 20:03:53 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id 1A49A487F3; Mon, 12 Mar 2007 21:03:52 +0100 (CET) Received: from localhost (154.81.datacomsa.pl [195.34.81.154]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id 5F7254569A; Mon, 12 Mar 2007 21:03:46 +0100 (CET) Date: Mon, 12 Mar 2007 21:03:45 +0100 From: Pawel Jakub Dawidek To: John Baldwin Message-ID: <20070312200345.GB5688@garage.freebsd.pl> References: <200703092241.l29Mf2Ds062856@repoman.freebsd.org> <200703121116.24667.jhb@freebsd.org> <20070312185638.GA5688@garage.freebsd.pl> <200703121535.22140.jhb@freebsd.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="7iMSBzlTiPOCCT2k" Content-Disposition: inline In-Reply-To: <200703121535.22140.jhb@freebsd.org> X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 7.0-CURRENT i386 User-Agent: mutt-ng/devel-r804 (FreeBSD) X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=BAYES_00 autolearn=ham version=3.0.4 Cc: Attilio Rao , cvs-src@freebsd.org, src-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/share/man/man9 Makefile condvar.9 lock.9 mi_switch.9 mtx_pool.9 mutex.9 rwlock.9 sleep.9 sleepqueue.9 sx.9 thread_exit.9 src/sys/kern kern_synch.c src/sys/sys mutex.h rwlock.h sleepqueue.h sx.h systm.h X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Mar 2007 20:03:54 -0000 --7iMSBzlTiPOCCT2k Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Mar 12, 2007 at 03:35:21PM -0400, John Baldwin wrote: > On Monday 12 March 2007 14:56, Pawel Jakub Dawidek wrote: > > On Mon, Mar 12, 2007 at 11:16:23AM -0400, John Baldwin wrote: > > > On Saturday 10 March 2007 15:52, Pawel Jakub Dawidek wrote: > > > > What about something like this: > > > >=20 > > > > #define cv_wait(cv, lock) do { > > > > switch (LO_CLASSINDEX((struct lock_object *)(lock))) { > > >=20 > > > The problem with a cast is you use type checking. Might as well do t= his: > > >=20 > > > #define cv_wait(cv, lock) _cv_wait((cv), (struct lock_object *)(lock)) > >=20 > > This will skip type checking and my version only cast to provide type > > checking, so when you pass some random variable it will give you an > > error. >=20 > Not really, you may pass some garbage and the LO_CLASSINDEX turns out to = be a=20 > mutex. :) You only get a runtime error, not a compile-time one. =20 > Type-checking by the compiler is nice because you get compile-time errors. I'll get compile-time error, because cv_wait_mtx() takes 'struct condvar *' and 'struct mtx *' as arguments. So even if some garbage returns 1, which turns out to be a mutex, call to cv_wait_mtx() will generate compile-time error. But it seems the solution may not be that good if it is not very obvious on a first look. If typeof() thing works, its fine by me, just give me condvar(9) that works with sx(9) locks:) --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --7iMSBzlTiPOCCT2k Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (FreeBSD) iD8DBQFF9bIhForvXbEpPzQRAlOhAKDWngF4UQfgM8xuVhcsm64LxGmT0QCg93sQ 4p5R/rqb6GhGL5ztkesK17M= =vq/h -----END PGP SIGNATURE----- --7iMSBzlTiPOCCT2k--