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 23E92C5478C for ; Wed, 28 Feb 2024 03:21:32 +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-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=2TW6kLVf5jtG+uMoZdCFeIy+KwK91uf2Umpjd0rNMCo=; b=kctClAWU1Fpl1DGyRzYAGj1coU eMTs6r0TOICH5TpeWksOgJAnFLup7RpaD+xcT9d8FzTUtHT2+VDiU3qsozgeOxK7INcv84bVDMzli d2e4rzQJnYH5wJPz0mRwL+WLhi5FHrNBV2LHDb6oGOt0dSwdHDAcnL56gR0KUsrlawdRzA/rIBfMd YKix1kADxIh/Qhpw4hb2th64ftIQ0VFsdnrc5fjMgT7nxHGnTrgd/kvRTjBFQCxgOlqzkIYQMXYHc gXPGKcec+/Nb1os0pkrzYIO+m32vzLo253o2U7aQ2wc2cy22OwTG9Uv/ksxdUVhoTSfO3xJhg3OcO uInEhtcQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rfAVd-00000007pk5-1eOS; Wed, 28 Feb 2024 03:21:29 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rfAVa-00000007pjT-1uo3 for linux-nvme@lists.infradead.org; Wed, 28 Feb 2024 03:21:27 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id E73E961263; Wed, 28 Feb 2024 03:21:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3235AC433C7; Wed, 28 Feb 2024 03:21:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709090485; bh=r2s00amy8YnbQ4jcXFLPoZdaGH/++zdC7DXhiqx3kaA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qkNYbby6gs5jVq4lcbrReFjVcilIi28rsh+EhzMLHldwdcb++PYLDoBlwpg+qYLpP lbjnjU2GH+QfPqkTLQSMkqG3niDcz7vgaza1vvM+vEO17fhvFF2yBY57TqBrAVO8cp tUDggWX15vJ6ZFlzDez2YolPRwRNkJzla7yJ/exRd7NJI7hb2L5sKUGG9OG6zu2DSv ZtFYIF/rhTZCIOENlVfCeWmUcgtPkVp5Jnd7ME76lh1GbZTxmAhv1x943oA8k24UO4 6BMDykY7/Lvrj1oVJQ5QpGeflO5niiDZhWCbb+kNrkwlcgc//djSM3WhYUIJqIIsln ZhtpA9Fs1fpsA== Date: Tue, 27 Feb 2024 20:21:22 -0700 From: Keith Busch To: Guixin Liu Cc: Sagi Grimberg , hch@lst.de, kch@nvidia.com, linux-nvme@lists.infradead.org Subject: Re: [PATCH v7 1/1] nvmet: support reservation feature Message-ID: References: <20240201023207.112007-1-kanie@linux.alibaba.com> <20240201023207.112007-2-kanie@linux.alibaba.com> <0c74a2c2-c9d9-4b0c-9deb-bdc3caf72005@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0c74a2c2-c9d9-4b0c-9deb-bdc3caf72005@linux.alibaba.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240227_192126_625761_A9E2468D X-CRM114-Status: GOOD ( 21.04 ) 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, Feb 28, 2024 at 10:21:57AM +0800, Guixin Liu wrote: > > 在 2024/2/28 08:40, Sagi Grimberg 写道: > > Hey Guixin, > > > > On 01/02/2024 4:32, Guixin Liu wrote: > > > This patch implements the reservation feature, includes: > > > 1. reservation register(register, unregister and replace). > > > 2. reservation acquire(acquire, preempt, preempt and abort). > > > > > > Overall patchset looks in decent shape to me now. > > > > I do have one more question though. > My thanks for your patient review. > > > > You say that this patchset implements preempt and abort, however I don't > > see how this is actually implemented or even how can it be implemented > > at all at this point. > > Yes, the nvme target does not do any useful workto abort command, the > comment of nvmet_execute_abort() says that > > "we are not required to do any useful work, and we couldn't really do a > useful abort", > > so I don't know what to do about preempt and abort, and the NVMe spec says > that the abort is best effor. > > My statement here may be a little inaccurate. I think you may be mixing up the NVMe "Abort" command with a different command, "Reservation Acquire", where RACQA is set to value 010b, "Preempt and Abort".