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 F15F3C4167B for ; Wed, 28 Dec 2022 16:11:09 +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=L44cxfhQPFCzkCqKeSBLFXIo5CPG4foHwnhz4JuSsaE=; b=TRpQvgXOt0sOfygO5J+Oi96JnU mCzZW9bAa94W0E3QIpWPmgtFE/EJUEOu4KCH1kCWuAgrcruuR4T8qromGvEY+Qg7cY6Fi0fTKEC+3 sSmA6nTHfT7MspHxJn347Pkj87MHnQpWV82TcfXuY6AjjQAqnieJxmFk+ygoMH80E0E3FyPbtb3b7 +6oPKn4m5ifht01lFNcbZyHyPo6HSJEA4sqzX4SxkUAdWKJ69njUn16o9eF5g5V8A6NMIBy6t08oU 6QGNdngqfA7OthjRORUiWBhMeHsU4ewWO7q8cG2UGfc9wwmjtiCzfAvMNfq+X1tVf0RQkzkZuyoR/ WwOKYoww==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pAZ1G-006EZx-VW; Wed, 28 Dec 2022 16:11:06 +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 1pAZ17-006EPn-17 for linux-nvme@lists.infradead.org; Wed, 28 Dec 2022 16:11:00 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 91F6F68C7B; Wed, 28 Dec 2022 17:10:50 +0100 (CET) Date: Wed, 28 Dec 2022 17:10:50 +0100 From: Christoph Hellwig To: Sagi Grimberg Cc: Christoph Hellwig , Linus Torvalds , Jens Axboe , Keith Busch , Hugh Dickins , linux-nvme@lists.infradead.org Subject: Re: [PATCH 2/4] nvme-pci: update sqsize when adjusting the queue depth Message-ID: <20221228161050.GA849@lst.de> References: <20221225103234.226794-1-hch@lst.de> <20221225103234.226794-3-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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-20221228_081057_242527_C746D5E6 X-CRM114-Status: GOOD ( 14.17 ) 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 Sun, Dec 25, 2022 at 01:19:43PM +0200, Sagi Grimberg wrote: > But if you want to patches 1+2 to be taken before 3+4, I'd make sqsize > to be a 0's based value of q_depth after we subtract one entry for queue > wraparound. So others would not get affected from patches 1+2. Then in > one batch make all assignments to sqsize 1's based like in patch 3 and > change nvme_alloc_io_tagset at the same time. 1 doe not make any difference in the 0s based vs not values, they just reduce the queue size by 1 intentionally.