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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 520F0C4361B for ; Tue, 8 Dec 2020 01:42:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EBAE12389E for ; Tue, 8 Dec 2020 01:42:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725995AbgLHBmH (ORCPT ); Mon, 7 Dec 2020 20:42:07 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:41200 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725877AbgLHBmH (ORCPT ); Mon, 7 Dec 2020 20:42:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607391640; 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=CbTa3TS2UPjpV8MBdJe1uQo9hhOnX7CWEPeQVSLOHRo=; b=c5DNmMJkxVYC3tzcm8twYzIcGQFXNF7Cz7e44A5bbQMasUALZkbEgIJ49ZG43q50CoN/te Rb8VvVx3wlEiPgOHMK68jF8cQvH3u/EnswpUUMxQWU32pu5ynmp0p2Vx358siNz6DHVIXu VyrWMY/Gl4JEPt9YA0Qi8wuvSwkqLBI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-229-XgKGoatqPX-f8kPrH1Xf1Q-1; Mon, 07 Dec 2020 20:40:39 -0500 X-MC-Unique: XgKGoatqPX-f8kPrH1Xf1Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 30AF0800D55; Tue, 8 Dec 2020 01:40:37 +0000 (UTC) Received: from T590 (ovpn-13-16.pek2.redhat.com [10.72.13.16]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3345A5C22B; Tue, 8 Dec 2020 01:40:24 +0000 (UTC) Date: Tue, 8 Dec 2020 09:40:19 +0800 From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Qian Cai , Sumit Saxena , John Garry , Kashyap Desai , Bart Van Assche , Hannes Reinecke , linux-kernel@vger.kernel.org Subject: Re: [PATCH V2 0/3] blk-mq/nvme-loop: use nvme-loop's lock class for addressing lockdep false positive warning Message-ID: <20201208014019.GB1059392@T590> References: <20201203012638.543321-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201203012638.543321-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Dec 03, 2020 at 09:26:35AM +0800, Ming Lei wrote: > Hi, > > Qian reported there is hang during booting when shared host tagset is > introduced on megaraid sas. Sumit reported the whole SCSI probe takes > about ~45min in his test. > > Turns out it is caused by nr_hw_queues increased, especially commit > b3c6a5997541("block: Fix a lockdep complaint triggered by request queue flushing") > adds synchronize_rcu() for each hctx's release handler. > > Address the original lockdep false positive warning by simpler way, then > long scsi probe can be avoided with lockdep enabled. > > V2: > - add reviewed-by > - adjust commit log of patch 3 > > Ming Lei (3): > blk-mq: add new API of blk_mq_hctx_set_fq_lock_class > nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class > Revert "block: Fix a lockdep complaint triggered by request queue > flushing" > > block/blk-flush.c | 30 +++++++++++++++++++++++++----- > block/blk.h | 1 - > drivers/nvme/target/loop.c | 10 ++++++++++ > include/linux/blk-mq.h | 3 +++ > 4 files changed, 38 insertions(+), 6 deletions(-) > > Cc: Christoph Hellwig > Cc: Qian Cai > Cc: Sumit Saxena > Cc: John Garry > Cc: Kashyap Desai > Cc: Bart Van Assche > Cc: Hannes Reinecke > -- > 2.28.0 > Hello Jens, Ping... -- Ming