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 0FD15C54E58 for ; Mon, 11 Mar 2024 11:20:22 +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:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hyQUr8jGn3hIN05OzMWDA66EXbEY31C85c4ZhIxNXkc=; b=vWwP8LgW0xvRLrhO+0hJYCrpGo sa1AFJTAkfxMUFNTS9W/tk7sdKf4z9glaZ53IhzfUVQz9/RfO43cBnTEV5Iurk4q6lHUulCZzpJ02 pW1EB2HRsn9e+kv0NuDCPG0OuKqLPjL9H7wUGndiIZXw5FYKAcajFgPsMnyrphRtoMQzFDkknRPLy mM8ag/s89ub43pHWAZ9CfJeSb+PqYyeZMD2ufp3qW/sVUJua+aGJrJoFeutZcO4gC+V//QBdTyGLv R6+FYmxARQGb9WvMd0KPsu0aBUeIzMB9/k3Qas8W5i45MWVOZ9tCHwhYA5Er+BNlC0YCheVqf7Z6F EjP30fFg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rjdha-00000001FW7-1Uma; Mon, 11 Mar 2024 11:20:18 +0000 Received: from out30-124.freemail.mail.aliyun.com ([115.124.30.124]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rjdhV-00000001FTD-1UwE for linux-nvme@lists.infradead.org; Mon, 11 Mar 2024 11:20:16 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1710156001; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=hyQUr8jGn3hIN05OzMWDA66EXbEY31C85c4ZhIxNXkc=; b=AWTPahNrRFKpB4mVnYcVT7vMhK+7mw70lWVykG9qCM1aUA2R8ax5WFzZk3RsQhBHtAIbdUaJWvC+sTj/KVL8AwcO5VYe3kv+nDCN9X/wzWWLBZ9E/wQyqv1lCFhoDxwrSf+TftFLapP7dUeKBfEEC6wM0gubZEfFqAUiie1lPSo= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R671e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045170;MF=kanie@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0W2FpFbA_1710155997; Received: from 30.178.90.245(mailfrom:kanie@linux.alibaba.com fp:SMTPD_---0W2FpFbA_1710155997) by smtp.aliyun-inc.com; Mon, 11 Mar 2024 19:19:58 +0800 Message-ID: <8fccdd92-9055-45ba-8edb-8b2b647343b3@linux.alibaba.com> Date: Mon, 11 Mar 2024 19:19:56 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 1/1] nvmet: support reservation feature Content-Language: en-GB To: Sagi Grimberg , Keith Busch Cc: hch@lst.de, kch@nvidia.com, linux-nvme@lists.infradead.org References: <20240201023207.112007-1-kanie@linux.alibaba.com> <20240201023207.112007-2-kanie@linux.alibaba.com> <0c74a2c2-c9d9-4b0c-9deb-bdc3caf72005@linux.alibaba.com> <727aabbc-1464-48d6-9915-a1c22343c2b2@linux.alibaba.com> <6e34a652-da40-46f2-8a43-b45b08682e41@grimberg.me> <0c33b803-baff-45af-90bb-623822f756b8@linux.alibaba.com> From: Guixin Liu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240311_042013_928958_7ACDEAD6 X-CRM114-Status: UNSURE ( 7.31 ) X-CRM114-Notice: Please train this message. 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 >> >> What do you think Sagi? Or may be we can declare that >> preempt_and_abort is not supported, just >> >> like SPDK does. > > It can definitely come incrementally, but at the very least it should > be incorrectly supported. > > Out of curiosity, doesn't your use-case need a fencing protection > against inflight I/Os reordering during > preemption? The cluster use stonith(shoot the other node in the head) to protect sources, and the backend storage(our storage system goes like this, so does disk firmware I think.) can process write I/O operations on a first-come,first-served basis if the range of data accessed by two I/O operation overlaps, for example, hostB preempt and abort hostA, then host B send I/Os, the backend storage will handle hostA's I/O first(by the timestamp). Best regards, Guixin Liu