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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 9CF01C43387 for ; Sun, 16 Dec 2018 18:39:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B56B217FA for ; Sun, 16 Dec 2018 18:39:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730708AbeLPSjl (ORCPT ); Sun, 16 Dec 2018 13:39:41 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59606 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730686AbeLPSjl (ORCPT ); Sun, 16 Dec 2018 13:39:41 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8B8AFC049580; Sun, 16 Dec 2018 18:39:41 +0000 (UTC) Received: from localhost (unknown [10.18.25.149]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A780119C7C; Sun, 16 Dec 2018 18:39:38 +0000 (UTC) Date: Sun, 16 Dec 2018 13:39:37 -0500 From: Mike Snitzer To: Christoph Hellwig Cc: Ming Lei , Jens Axboe , linux-block@vger.kernel.org, Jeff Moyer Subject: Re: [PATCH 3/4] blk-mq: deal with shared queue mapping reliably Message-ID: <20181216183937.GA25476@redhat.com> References: <20181216022517.26650-1-ming.lei@redhat.com> <20181216022517.26650-4-ming.lei@redhat.com> <20181216161650.GD9957@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181216161650.GD9957@lst.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Sun, 16 Dec 2018 18:39:41 +0000 (UTC) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Sun, Dec 16 2018 at 11:16am -0500, Christoph Hellwig wrote: > On Sun, Dec 16, 2018 at 10:25:16AM +0800, Ming Lei wrote: > > This patch sets map->nr_queues as zero explictly if there is zero > > queues for such queue type, then blk_mq_map_swqueue() can become > > more robust to deal with shared mappings. > > This looks a lot more clumsy than what we had before, can you explain > what additional robustnes it buys us? It enables nvme IO to complete on my testbed with for-4.21/block changes, this NUMA layout is what triggered Ming's work: # numactl --hardware available: 2 nodes (0-1) node 0 cpus: 0 2 4 6 8 10 12 14 node 0 size: 128605 MB node 0 free: 128092 MB node 1 cpus: 1 3 5 7 9 11 13 15 node 1 size: 128997 MB node 1 free: 128529 MB node distances: node 0 1 0: 10 21 1: 21 10 Without the aggregate changes from this patchset (1-3 anyway) I get IO hangs in blkdev_fsync(). With that in mind, Jens needs these fixes (or something comparable) ASAP. Tested-by: Mike Snitzer