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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 9C74DC28CBC for ; Wed, 6 May 2020 14:42:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7716120836 for ; Wed, 6 May 2020 14:42:53 +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="V5MUZQuU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728848AbgEFOmw (ORCPT ); Wed, 6 May 2020 10:42:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728712AbgEFOmw (ORCPT ); Wed, 6 May 2020 10:42:52 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C678C061A0F for ; Wed, 6 May 2020 07:42:52 -0700 (PDT) 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; bh=9nDYZVwSxSRpeC1wdsh5D1kQnUR+aLyr8r0T28AhYKs=; b=V5MUZQuUsHBMc4Dmw0Wi/KDPIN 7rBJcCKdWoFlauu8F+m9YkCoUuurK41rAzvBFbTcCQr+HkjzKneOS/PKnhy3hWl7BzvMyaAKjaEez Zympq5BGOIqQam5LrMWyNxbQ2zq2WXmGPpRi02GuhEKsrXgICql7oseE3zd0vb89aI0FeOf95xHsx LQCG/s+RtXyoPWANVNILRlKgTB5AuwGuy45ls1MzrTteWSpqrksgFUm300CoqBM6Z264yynuLLYLD eZhD5kWYMY0xuIiFtdBM+2RLkP+AQE1ECHqPdWQIDQdsAu/9E4sM5ni2lCq0Wltwx9R4gZSczmeNZ +SAOmXdQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWLG7-00020t-Uu; Wed, 06 May 2020 14:42:51 +0000 Date: Wed, 6 May 2020 07:42:51 -0700 From: Christoph Hellwig To: Jan Kara Cc: Jens Axboe , linux-block@vger.kernel.org Subject: Re: [PATCH 0/3] Fix blkparse and iowatcher for kernels >= 4.14 Message-ID: <20200506144251.GA7564@infradead.org> References: <20200506133933.4773-1-jack@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200506133933.4773-1-jack@suse.cz> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, May 06, 2020 at 03:39:30PM +0200, Jan Kara wrote: > I was investigating a performance issue with BFQ IO scheduler and I was > pondering why I'm not seeing informational messages from BFQ. After quite > some debugging I have found out that commit 35fe6d763229 "block: use > standard blktrace API to output cgroup info for debug notes" broke standard > blktrace API - namely the informational messages logged by bfq_log_bfqq() > are no longer displayed by blkparse(8) tool. This is because these messages > have now __BLK_TA_CGROUP bit set and that breaks flags checking in > blkparse(1) and iowatcher(1). This series fixes both tools to be able to > cope with events with __BLK_TA_CGROUP flag set. I'd much rather revert a kernel change that breaks frequently used userspace.