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=-5.2 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 BDACCC433E1 for ; Thu, 20 Aug 2020 06:10:42 +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 88B6D2078D for ; Thu, 20 Aug 2020 06:10:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="KnjgdDVZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 88B6D2078D 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=Xqil1pp3cfV/BvxjUxcx/fehPil+2VJ6fGHOdLnsTjA=; b=KnjgdDVZ3oTLkvWxeRRUG4S/J DErUFsv/y1g/DphDCvkAUL+XFDSxtKB/YkN+Pbou1RBOujV+lFZuo5jTtshOLF+sSXlThbGmjInLv mchJvKQRa2Zsaweecp27n5MtX2ytvZ00eMMQ+vGKMSWEj+osfXReTqYRoIYGxtGb+Yy5DBQGhuNKS RYd/D77hKOn8iNJ+YFNbgh4s0f8sbLan4efGCHh3n5AwAIsadkPEXQxMBlqdzs33v57cBsui2ar8g EjF8rfY8trc1L4P/6tLHmP46HBI99590ISKXPwS7oOkhppn5Y0dKX7gDjiYCKGBbvYb4NyEP3i01u WvJOY6h9Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k8dmZ-0006mg-R8; Thu, 20 Aug 2020 06:10:39 +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 1k8dmV-0006l5-LQ for linux-nvme@lists.infradead.org; Thu, 20 Aug 2020 06:10:36 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 0DFFA68BEB; Thu, 20 Aug 2020 08:10:34 +0200 (CEST) Date: Thu, 20 Aug 2020 08:10:33 +0200 From: Christoph Hellwig To: Sagi Grimberg Subject: Re: [PATCH v3 8/9] nvme-rdma: fix timeout handler Message-ID: <20200820061033.GD6188@lst.de> References: <20200820053651.197057-1-sagi@grimberg.me> <20200820053651.197057-9-sagi@grimberg.me> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200820053651.197057-9-sagi@grimberg.me> 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-20200820_021035_870156_563ABC1B X-CRM114-Status: GOOD ( 17.25 ) 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: Keith Busch , Christoph Hellwig , linux-nvme@lists.infradead.org, James Smart 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 Wed, Aug 19, 2020 at 10:36:50PM -0700, Sagi Grimberg wrote: > When a request times out in a LIVE state, we simply trigger error > recovery and let the error recovery handle the request cancellation, > however when a request times out in a non LIVE state, we make sure to > complete it immediately as it might block controller setup or teardown > and prevent forward progress. > > However tearing down the entire set of I/O and admin queues causes > freeze/unfreeze imbalance (q->mq_freeze_depth) because and is really > an overkill to what we actually need, which is to just fence controller > teardown that may be running, stop the queue, and cancel the request if > it is not already completed. > > Now that we have the controller teardown_lock, we can safely serialize > request cancellation. This addresses a hang caused by calling extra > queue freeze on controller namespaces, causing unfreeze to not complete > correctly. I still think this should be dev_info instead of dev_warn, but otherwise: Reviewed-by: Christoph Hellwig _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme