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 X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53485C34031 for ; Tue, 18 Feb 2020 23:10:20 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 25DE224656 for ; Tue, 18 Feb 2020 23:10:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="TMEchPxT"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rzkUrxa0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 25DE224656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject: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=LFRv7yAcNesWkwApe0rHNsKUcInB0MJuhgZR3z4lqMU=; b=TMEchPxT75RVPQ ojQJs7zVYShuvweJZtPhLdsvIOffeoKIWLDpNV6S+FThNpZdTddbTzjYGr+gGWsxg8Qw4KviPmVJX vuDQA5YAcizUtGbcNJXdTyK5i/B8dPXAln+yneab+6Uf6CeCpGFh7tlfUpW0bz+pHAYHTKp43e/If Y9Weq6J9B9NEJemw97XSYYTxkV5u4kfnSCU5JEip/disk/HksacYCh4cZ2SJw3p8WbMZJtvofHEJR fCkqetS44gXQDW6jane4TUm3dP+ODvkl02iRz/UInmB0Juw3a5iao9RAyFcZ1XvNV0yFw+q3uauar w9gYKD4P/c2SS+XEz6Aw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j4C0Q-00028i-1p; Tue, 18 Feb 2020 23:10:18 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j4C0N-000287-Ez for linux-nvme@lists.infradead.org; Tue, 18 Feb 2020 23:10:16 +0000 Received: from redsun51.ssa.fujisawa.hgst.com (unknown [199.255.47.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2FE8824125; Tue, 18 Feb 2020 23:10:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582067413; bh=v22+PgN7H/B4xPUCRQ1DsVyP8e4CnicZgkLDe5nMRM4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rzkUrxa0vOpSt+Rq1R5CHO5S/9jEyieSZfu0s5vYe43c2cCy7uCdSwHOEuBgDXhTb QdxOVQ4Qv0IcDRTxIDmGxCBWq+ILQvyIGNcSH+sMozXWeW/eiyl4ua+S/xTq5JsniD 6j13BRytmVUpKH7tE2krnYTz0WGdseYhtxHNc6L0= Date: Wed, 19 Feb 2020 08:10:07 +0900 From: Keith Busch To: Chaitanya Kulkarni Subject: Re: [PATCH 0/4] nvmet: add set feature based timestamp support Message-ID: <20200218231007.GA18306@redsun51.ssa.fujisawa.hgst.com> References: <20200218214338.25088-1-chaitanya.kulkarni@wdc.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200218214338.25088-1-chaitanya.kulkarni@wdc.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200218_151015_607251_5B5FCCE1 X-CRM114-Status: GOOD ( 14.11 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: hch@lst.de, linux-nvme@lists.infradead.org, sagi@grimberg.me Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Feb 18, 2020 at 01:43:34PM -0800, Chaitanya Kulkarni wrote: > This is a small patch-series which implements set-feature based > controller timestamp feature support for NVMeOF Target controller. > This allows host to set the timestamp using set feature and read it > with get feature commands when controllers are distributed across > different systems. We return the value set with a Set Features > command for the current value plus the elapsed time since being set. > NVMe [1]. > > Regards, > Chaitanya > > [1] NVMExpress Revision 1.4 (Page 220) Set Timestamp Origin -> 001b. > > Chaitanya Kulkarni (4): > nvmet: use nvmet_feat_data_len consistently > nvmet: add support for set-feat-timestamp cmd > nvmet: add support for get-feat-timestamp cmd > nvmet: update ctrl oncs values for timestamp Patch 1 looks good. The last three ought to be a single patch IMO since those should really from an inseparable package deal for this feature. My only comment on the implementation is you need to initialize nvmet_ctrl 'ts' and 'local_ts' on each reset so that we have correct values to report in case the host never sets the timestamp. As to why we'd support this feature, the spec says "The use of the Timestamp is outside the scope of this specification". Is there anything interesting we can do with this? _______________________________________________ linux-nvme mailing list linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme