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=-5.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 4F1AAC433E0 for ; Mon, 18 Jan 2021 17:41:16 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 A2387223E8 for ; Mon, 18 Jan 2021 17:41:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A2387223E8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de 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=merlin.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=wWjNYXbadU/pxXR8llrHe2I7LOH9+s5mvuk3yEq8aDM=; b=vBdrpoOX8RHoSrI8Yp/DxZBhZ ae5MnBBc/5dT4g6PQmJPU5t7KpuzuNsfIhx+KrTz9V/VG3tA3yPTguvbW1Cf9n8UJ5L0OL4TtYST7 u3Yirb88EaSfCxWuJJkSZRcZ+7h3IpZQtmdP5nej923/G6fix5jNDHYaq6/cqSb7Bv2p73y9JvxOH 1EBN4uQdhSfiI5i22ygcYojLW5dYlOGM3jclEAiIFeBl8EI2UIoFnDKlX2PhdRAb7/zv79BRaatX/ jdbfknLtaevcj9QuvFr0vfwZryU4uwrkIkD6qLhBTcgQVYGuJA3PwipLEnjAeQ2wCm6CLjToBkVC2 bhl/Pg4dA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l1YWZ-0003GW-Ll; Mon, 18 Jan 2021 17:41:07 +0000 Received: from verein.lst.de ([213.95.11.211]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l1YWT-0003FZ-HU for linux-nvme@lists.infradead.org; Mon, 18 Jan 2021 17:41:02 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id ED1BE6736F; Mon, 18 Jan 2021 18:40:51 +0100 (CET) Date: Mon, 18 Jan 2021 18:40:51 +0100 From: Christoph Hellwig To: Minwoo Im Subject: Re: [PATCH V3 3/3] nvme: retry commands based on ACRE flag Message-ID: <20210118174051.GA8542@lst.de> References: <20210114133110.20779-1-minwoo.im.dev@gmail.com> <20210114133110.20779-4-minwoo.im.dev@gmail.com> <20210115170412.GA1515933@dhcp-10-100-145-180.wdc.com> <20210115182602.GA2822@localhost.localdomain> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210115182602.GA2822@localhost.localdomain> 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-20210118_124101_718111_70A6D665 X-CRM114-Status: GOOD ( 17.05 ) 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: Sagi Grimberg , linux-nvme@lists.infradead.org, Jens Axboe , Chao Leng , Keith Busch , Christoph Hellwig 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 Sat, Jan 16, 2021 at 03:26:02AM +0900, Minwoo Im wrote: > > I am not sure we should ignore the FAILFAST for non-path errors. If we > > need retryable admin commands, we should let the driver provide a way > > for callers to dispatch requests without that flag. > > Understood. I thought the opposite way about FAILFAST in case with > acre, if device is enabled with acre, all commands would be retried > regardless to FAILFAST... Thanks for pointing that out! > > How do you think which one is right choice to go with if a user-space > application(e.g., nvme-cli) wants a command to be retired in case of > ACRE && Error && !DNR: > > - User-space application should figure out !DNR and retry the command. > (Maybe we are not able to easily figure out exact status code from > the user-space application by the return value). > > - Driver should retry the command right before putting result up to > the user-space even it's a FAILFAST request. > > Thanks, We could come up with a version of the ioctls that use the normal retry mechanisms. nvme_passthru_cmd64 has two reserved fields we could use for UAPI flags like this. _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme