From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 78FD8C433F5 for ; Thu, 30 Dec 2021 08:04:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Lb7kM4YAisHWG/xpOq2BUblqPQsH2mfIVfpAb4VIglk=; b=KmquCSdcZpP/aXCYtQTZtoK6OS 8dxDNxqkyzOx7cmOig8Z10nH1HtLKbASHqtksb4ZNDEpX2ij2XvviWF154n0/E3YFYxynaTq+388t 5HhnrnyGAEsu7C1EeKtJuONm8OyeqZ2Ai41hlzWSA6fJ8KlDWaUk7U5Ilp2zF/dalM4OuZi00ugf8 6HEpUKQ22sM/LrMFnS6ImSIXHvIrfb09iXY296+Xh8rgMyFCD9jRgZ745gzkxglFkHn0IAt56crWV 5Ndq7DY4wlqbB4pHgpRx9ekzeP7/bb+/dYg/Vkn1OyFg2qEoy3u95iw8km1OMg3FAygFbbT74mKR9 cwSf6SRQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n2qQ6-003zJT-Ae; Thu, 30 Dec 2021 08:04:18 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n2qG2-003vJi-I8 for linux-nvme@lists.infradead.org; Thu, 30 Dec 2021 07:53:56 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 715A768AFE; Thu, 30 Dec 2021 08:53:48 +0100 (CET) Date: Thu, 30 Dec 2021 08:53:48 +0100 From: Christoph Hellwig To: Keith Busch Cc: Christoph Hellwig , linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, axboe@kernel.dk, sagi@grimberg.me Subject: Re: [PATCHv2 3/3] nvme-pci: fix queue_rqs list splitting Message-ID: <20211230075348.GA5073@lst.de> References: <20211227164138.2488066-1-kbusch@kernel.org> <20211227164138.2488066-3-kbusch@kernel.org> <20211229174602.GC28058@lst.de> <20211229210446.GC2493133@dhcp-10-100-145-180.wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211229210446.GC2493133@dhcp-10-100-145-180.wdc.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211229_235354_794152_2627AF22 X-CRM114-Status: GOOD ( 16.82 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Wed, Dec 29, 2021 at 01:04:46PM -0800, Keith Busch wrote: > On Wed, Dec 29, 2021 at 06:46:02PM +0100, Christoph Hellwig wrote: > > > + rq_list_move(rqlist, &requeue_list, req, prev, next); > > > + > > > + req = prev; > > > + if (!req) > > > + continue; > > > > Shouldn't this be a break? > > The condition just means we're at the beginning of the rqlist. There may > be more requests to consider, so we have to continue. > > Or are you saying any failed prep should just abandon the batched > sequence? If so, we would need to concat the return list with the rest > of rqlist before breaking. No, I misunderstood the check,