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 41FE5E77188 for ; Thu, 9 Jan 2025 01:59:28 +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=imjPGe2wWwbZPrTyZsznpVBVYJYH04fIhX7CpX3xCfM=; b=w/BcNP6q2Oud0SZfZXjoe0ocSQ i5ffmJSkQcayXNe8UkXs3QWkqaYrwn7xJgfcxrx+2hSjB3Nc4YMtQVFI9WcRwRFd0sNEytucOA3WB TjfTsEXgwjoSTpVCs00/W8mNeRKuETAiU04TOpsS1MvSzbGW850SuBA3yEL9MaD2tdd3nCuyZBDx0 ofTAqgIkqcVUYhnWijQQUXECASeBSZ86H1mBBoHyWTvHf6WFc04OY5jMt1wjx02n4RK99aEYoCTW5 ymIOm7Jx3EScxIqFwrnBoG++IZScrZA9myY2t4T8/1TyucrHZpfXYfbjz0KzqGO2ssLDK45gbidU4 k+fiHQxg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tVhpV-0000000AMcw-1v3a; Thu, 09 Jan 2025 01:59:25 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tVhpR-0000000AMcP-1GM5 for linux-nvme@lists.infradead.org; Thu, 09 Jan 2025 01:59:24 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1736387959; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=imjPGe2wWwbZPrTyZsznpVBVYJYH04fIhX7CpX3xCfM=; b=iOPXxbH8JuNtFjAm1v2YOIs+qEM2jnL0prrEFqZ4/iNnMdrRtNGeZLLihF6/ZYt+kV4plV +v/3EDOumK9CYtZ7azc1Zwi9ozbQruNK7hw9vLV7S6gQdsMi4C8YJjprXJ0jzlbJOTiRbJ 93AnKaSPsIUArevvlkEdz24KOn2X+pQ= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-336-U6GY-sVXMNeOT_9J5cJOWw-1; Wed, 08 Jan 2025 20:59:18 -0500 X-MC-Unique: U6GY-sVXMNeOT_9J5cJOWw-1 X-Mimecast-MFC-AGG-ID: U6GY-sVXMNeOT_9J5cJOWw Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8E75A19560BB; Thu, 9 Jan 2025 01:59:15 +0000 (UTC) Received: from fedora (unknown [10.72.116.23]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 6146219560AB; Thu, 9 Jan 2025 01:59:08 +0000 (UTC) Date: Thu, 9 Jan 2025 09:59:03 +0800 From: Ming Lei To: Mohamed Khalfella Cc: James Smart , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, randyj@purestorage.com, jrani@purestorage.com Subject: Re: nvme-fc: Question about __nvme_fc_abort_outstanding_ios() Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250108_175921_414396_91BEAA72 X-CRM114-Status: GOOD ( 15.20 ) 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 Wed, Jan 08, 2025 at 05:32:10PM -0800, Mohamed Khalfella wrote: > Hello, > > I was looking at this code and I had a question about it. > > drivers/nvme/host/fc.c > 2473 static void > 2474 __nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues) > 2475 { > ... > ... > 2503 blk_mq_tagset_busy_iter(&ctrl->tag_set, > 2504 nvme_fc_terminate_exchange, &ctrl->ctrl); > 2505 blk_mq_tagset_wait_completed_request(&ctrl->tag_set); > > nvme_fc_terminate_exchange() calls __nvme_fc_abort_op() to abort all active > ops with status FCPOP_STATE_ACTIVE. I think these active ops map to in-flight > requests MQ_RQ_IN_FLIGHT. After blk_mq_tagset_busy_iter() returns it is not > guaranteed that all ops had done callback functions called on them. Some > of these requests might still be in-flight. > > blk_mq_tagset_wait_completed_request() makes sure that we do not have pending > completed requests, but it does not check for in-flight requests? It is because many callbacks call blk_mq_complete_request() to complete request, and the request may be completed remotely via IPI, that is why blk_mq_tagset_wait_completed_request() is needed. Thanks, Ming