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 E8A05C76196 for ; Tue, 28 Mar 2023 16:43:41 +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=qZR6cbXQdwB5nUHvEEH2VeiB5R9CC8hRiYSzmgcjAyg=; b=MGe9d0LgIyB9en52G74T8zK1YB DHtwI4DZ6ujM5wQJYHC0KbpLvYNGG8Yj31LcJRu3nZ3Hc6IJkckzsfMYD74XSbAeSjBn4B4ARGBb1 MYHs2PptLZIkwEfeTgdQtMSMXvUxYRl8RtE69yHxPQzhAZOcznGjEOA8zLn4LR0DRbHafojXxyMG3 YXZT3FEHOYZelPv+VcYdvzUULGI6iRPI/H4TC1RDKrxWh5u01GMf1PgWzkKk6RqhabmT7xAAgfX/+ tqtLSXDpNPPDwDzCbyxhmxEJI9Hk81e15QBqjfLV7CoBA5CnNr698RnkO9uaWn0SmMMbUHP5DYMnU 7vvVxwFA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1phCQ2-00FAUm-2L; Tue, 28 Mar 2023 16:43:34 +0000 Received: from mail-oa1-f54.google.com ([209.85.160.54]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1phCPz-00FATZ-25 for linux-nvme@lists.infradead.org; Tue, 28 Mar 2023 16:43:32 +0000 Received: by mail-oa1-f54.google.com with SMTP id 586e51a60fabf-17ec8963db8so13316895fac.8 for ; Tue, 28 Mar 2023 09:43:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680021809; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=qZR6cbXQdwB5nUHvEEH2VeiB5R9CC8hRiYSzmgcjAyg=; b=5XgFBKGK1jTDz3jFA9oLGM/wthKKQHcGFi0og+TTHCE18rBqFKAR1sM4XwDwfCIR26 5Gq3pYWCbpPYaO1/xZZ1x2DvTJcamMR+imNxqkVoRpwFuCdgnKUCXEPF7eZLjiu3cCuQ gnxgqTF6ucSrWHjWcTH+wJu4LO8aXzuqtc2LO74U0rCAauvaz/PpmQAGfsCgICtIHKRh zioxMUpqyxeO8D0cPeJXklwCHOaDdzWzVgKQkdp/PMk7rxehaAskUtmikY1IKGmxDyZD h8BPBdBBAvzd+ajcSSFHh9EiMF+wK2JNwHbNxFPEfflgXizi3wXUirdUcAxFM1zoyIZB C7rg== X-Gm-Message-State: AAQBX9dXwHqdBK1eR+KoMGFsMFP7BrIFYi/c5YZI4oxHFTFlWnCdZQGN u3pPU0mYH/noS9VXzrZjzeJ5EJ8G3ZSKS5FwFHO6 X-Google-Smtp-Source: AK7set8/4ablYvt1w3rWWxBu5RP3Per1gtZi0bV85eHN9m6lD3okcPGkDhxHJ2UAhi56YjYdObx6pQ== X-Received: by 2002:ac8:7d46:0:b0:3e3:95fb:8771 with SMTP id h6-20020ac87d46000000b003e395fb8771mr28046888qtb.31.1680021371021; Tue, 28 Mar 2023 09:36:11 -0700 (PDT) Received: from localhost (pool-68-160-166-30.bstnma.fios.verizon.net. [68.160.166.30]) by smtp.gmail.com with ESMTPSA id t23-20020ac865d7000000b003b635a5d56csm15765739qto.30.2023.03.28.09.36.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Mar 2023 09:36:10 -0700 (PDT) Date: Tue, 28 Mar 2023 12:36:09 -0400 From: Mike Snitzer To: Mike Christie Cc: bvanassche@acm.org, hch@lst.de, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, james.bottomley@hansenpartnership.com, linux-block@vger.kernel.org, dm-devel@redhat.com, axboe@kernel.dk, linux-nvme@lists.infradead.org, chaitanyak@nvidia.com, kbusch@kernel.org, target-devel@vger.kernel.org, Chaitanya Kulkarni Subject: Re: [PATCH v5 01/18] block: Add PR callouts for read keys and reservation Message-ID: References: <20230324181741.13908-1-michael.christie@oracle.com> <20230324181741.13908-2-michael.christie@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230324181741.13908-2-michael.christie@oracle.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230328_094331_682330_3BB74B1E X-CRM114-Status: GOOD ( 11.25 ) 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 Fri, Mar 24 2023 at 2:17P -0400, Mike Christie wrote: > Add callouts for reading keys and reservations. This allows LIO to support > the READ_KEYS and READ_RESERVATION commands and will allow dm-multipath > to optimize it's error handling so it can check if it's getting an error > because there's an existing reservation or if we need to retry different > paths. Not seeing anything in DM's path selectors that adds these optimizations. Is there accompanying multipath-tools callouts to get at this data to optimize path selection (via DM table reloads)? Mike