From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: SCSI QLA not working on latest *-mm SN2 Date: Tue, 21 Sep 2004 18:33:54 -0400 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <200409211833.55343.jbarnes@engr.sgi.com> References: <20040917183029.GW642@parcelfarce.linux.theplanet.co.uk> <20040921211108.GA16153@parcelfarce.linux.theplanet.co.uk> <20040921214302.GG146363@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from omx2-ext.sgi.com ([192.48.171.19]:12777 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S266613AbUIUWe0 (ORCPT ); Tue, 21 Sep 2004 18:34:26 -0400 In-Reply-To: <20040921214302.GG146363@sgi.com> Content-Disposition: inline List-Id: linux-scsi@vger.kernel.org To: Jeremy Higdon Cc: Matthew Wilcox , Grant Grundler , James Bottomley , Matthew Wilcox , Andrew Vasquez , pj@sgi.com, SCSI Mailing List , mdr@cthulhu.engr.sgi.com, jeremy@cthulhu.engr.sgi.com, djh@cthulhu.engr.sgi.com, Andrew Morton On Tuesday, September 21, 2004 5:43 pm, Jeremy Higdon wrote: > > > CPUA: writel(value_X, common_register) > > > sn_mmiob() > > > spin_unlock(common_lock) > > > > > > CPUB: spin_lock(common_lock) > > > writel(value_Y, common_register) > > > > > > would strongly order the writes. > > > > I think your _raw_spin_unlock() should include an sn_mmiob(). > > That could be very painful. > On Irix, we actually had a separate spinunlock (io_spin_unlock) that > added the MIPS equivalent. I'm assuming we don't want to entertain > that here :-) (Though tell me if I'm wrong) It's worth noting that this affects some MIPS systems as well, so that's at least two Linux arches that would benefit from a nice solution to this problem. Jesse