From owner-cvs-all Wed Jan 19 23:13:45 2000 Delivered-To: cvs-all@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id F0A2514D90; Wed, 19 Jan 2000 23:13:42 -0800 (PST) (envelope-from bright@fw.wintelcom.net) Received: (from bright@localhost) by fw.wintelcom.net (8.9.3/8.9.3) id XAA21035; Wed, 19 Jan 2000 23:37:02 -0800 (PST) Date: Wed, 19 Jan 2000 23:37:02 -0800 From: Alfred Perlstein To: Jason Evans Cc: Bruce Evans , cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/kern vfs_aio.c Message-ID: <20000119233702.E20751@fw.wintelcom.net> References: <20000119210539.F20191@fw.wintelcom.net> <20000119225846.W27689@sturm.canonware.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: <20000119225846.W27689@sturm.canonware.com>; from jasone@canonware.com on Wed, Jan 19, 2000 at 10:58:46PM -0800 Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk * Jason Evans [000119 23:24] wrote: > On Thu, Jan 20, 2000 at 05:50:09PM +1100, Bruce Evans wrote: > > On Wed, 19 Jan 2000, Alfred Perlstein wrote: > > > > > * Jason Evans [000119 18:23] wrote: > > > > jasone 2000/01/19 18:00:00 PST > > > > > > > > Modified files: > > > > sys/kern vfs_aio.c > > > > Log: > > > > Don't tsleep() while at splbio(). > > > > > > Unless it fixes some other bug, sleeping with spl raised is perfectly valid. > > > > And usually necessary to avoid races (Locking 101, part 3: an spl is > > not a lock...). However, it may not be necessary in vfs_aio.c, since > > the wakeups may only come from other processes and not from interrupt > > handlers. vfs_aio.c sleeps outside of an spl'ed section in about 6 > > other places, including 2 in very similar code. > > The person who sent me the patch was convinced that it was a necessary > change due to problems he had run into, and he convinced me at the time, > though my understanding of the code isn't great. > > Contrary to a previous statement, I'm going to leave the code as is for now > and actually write some test code to try to produce a problem with/without > the change. Can you post the issue he brought up that needed the spl lifted? > > Jason -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message