From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: WARNING: at drivers/ata/libata-core.c:5988 ata_qc_issue() Date: Fri, 25 Jan 2008 13:08:59 +0900 Message-ID: <479960DB.8050109@gmail.com> References: <4798ACCC.3040104@rtr.ca> <4798AE28.4000408@gmail.com> <4798B526.4020709@rtr.ca> <47992115.6050501@gmail.com> <479924B5.5060202@rtr.ca> <479925FF.4060501@gmail.com> <4799270D.3010009@rtr.ca> <4799285F.3060308@gmail.com> <47995EFD.8030102@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from wa-out-1112.google.com ([209.85.146.181]:33751 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752002AbYAYEJF (ORCPT ); Thu, 24 Jan 2008 23:09:05 -0500 Received: by wa-out-1112.google.com with SMTP id v27so809897wah.23 for ; Thu, 24 Jan 2008 20:09:04 -0800 (PST) In-Reply-To: <47995EFD.8030102@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mark Lord Cc: IDE/ATA development list Mark Lord wrote: > Tejun Heo wrote: >> Mark Lord wrote: > .. >>> Super. And when I add FIS-based-switching PMP support on top of NCQ, >>> *then* what should it point at? >> >> If the controller can do FIS-based switching w/o any other restrictions, >> ata_std_qc_defer() can just stay. If there are restrictions, you need >> to roll your own qc_defer. sata_sil24 had to. >> >> For command-based switching, sata_pmp_qc_defer_cmd_switch() can be used. > ... > > Super! You've done a great job with this stuff, Tejun! Thanks but I can't really say nice things about how sata_sil24's qc_defer() is implemented or how we generally handle command deferring. We really need the control at the higher level - request_queue group. Oh well... I guess you guys will be talking about it over beer again soon. :-) -- tejun