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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 AED19C43381 for ; Tue, 26 Feb 2019 14:33:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7C15220863 for ; Tue, 26 Feb 2019 14:33:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="bEJL+AqZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727505AbfBZOdP (ORCPT ); Tue, 26 Feb 2019 09:33:15 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:44272 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726018AbfBZOdP (ORCPT ); Tue, 26 Feb 2019 09:33:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=o6dOVRu9jS4FLZHx9jUnQL6CLbOLmEOSdt9NKZqrEcg=; b=bEJL+AqZLEWHzKwqjCqa77jYH jzDyDeOfMHQUOHywoBogizkX78XMe+3WDcOcP2Ybr9NcSQ1Nfy1kmN9uoqy70g/rFURaDJR/tFXx8 8U3wwC6UUBJLr7Ygf237YoSLPldB8a6I6LwHHe4fb9tTfX1C7/OtqN01k3lyk2BjGre+iwxsqBbML lTm74gAwpGpbkYf4C5YMyoFj4tN2dxppNjflgtenJa2grBD3e1QhxDIbGCc8BxoOcXNbOpK2lu8gZ RD6ml8WKhRPfBrFL0skVSZ2Af5mCpkpNd0N/eXsp8GQR1c9erPl3kaqWufXI+SpXNyGAvfR0EahUk ssKNjqfCA==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gydnF-0006Jj-FI; Tue, 26 Feb 2019 14:33:13 +0000 Date: Tue, 26 Feb 2019 06:33:13 -0800 From: Christoph Hellwig To: Hannes Reinecke Cc: Sreekanth Reddy , linux-scsi , Sathya Prakash , Suganath Prabu Subramani , stable@vger.kernel.org Subject: Re: [PATCH v1] mpt3sas: Use driver scsi lookup to track outstanding IOs Message-ID: <20190226143313.GA23865@infradead.org> References: <1550751105-46065-1-git-send-email-sreekanth.reddy@broadcom.com> <61a8f703-3f20-b777-08b9-54ae34dffa59@suse.de> <0dfb09ca-8723-3a3c-a6a8-c643856c57e3@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0dfb09ca-8723-3a3c-a6a8-c643856c57e3@suse.de> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Tue, Feb 26, 2019 at 02:49:30PM +0100, Hannes Reinecke wrote: > Attached is a patch to demonstrate my approach. > I am aware that it'll only be useful for latest upstream where the legacy > I/O path has been dropped completely, so we wouldn't need to worry about it. > For older releases indeed you would need to with something like your > proposed patch, but for upstream I really would like to switch to > blk_mq_tagset_busy() iter. While this is better than the driver private tracking we really should not have to iterate all outstanding command, because if we have any there is a bug we need to fix in the higher layers instead of working around it in the drivers.