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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 5F7DAC3A5A9 for ; Wed, 4 Sep 2019 21:14:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3FCC921726 for ; Wed, 4 Sep 2019 21:14:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726358AbfIDVO6 (ORCPT ); Wed, 4 Sep 2019 17:14:58 -0400 Received: from mail104.syd.optusnet.com.au ([211.29.132.246]:52252 "EHLO mail104.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725965AbfIDVO6 (ORCPT ); Wed, 4 Sep 2019 17:14:58 -0400 Received: from dread.disaster.area (pa49-181-255-194.pa.nsw.optusnet.com.au [49.181.255.194]) by mail104.syd.optusnet.com.au (Postfix) with ESMTPS id 9AC4843EBC2; Thu, 5 Sep 2019 07:14:55 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92) (envelope-from ) id 1i5ccA-0007Vk-Ag; Thu, 05 Sep 2019 07:14:54 +1000 Date: Thu, 5 Sep 2019 07:14:54 +1000 From: Dave Chinner To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org Subject: Re: [PATCH 3/7] xfs: factor debug code out of xlog_state_do_callback() Message-ID: <20190904211454.GF1119@dread.disaster.area> References: <20190904042451.9314-1-david@fromorbit.com> <20190904042451.9314-4-david@fromorbit.com> <20190904061038.GC12591@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190904061038.GC12591@infradead.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.2 cv=FNpr/6gs c=1 sm=1 tr=0 a=YO9NNpcXwc8z/SaoS+iAiA==:117 a=YO9NNpcXwc8z/SaoS+iAiA==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=kj9zAlcOel0A:10 a=J70Eh1EUuV4A:10 a=7-415B0cAAAA:8 a=ZgVjJpqDj-T1eQ5lgFAA:9 a=CjuIK1q_8ugA:10 a=biEYGPWJfzWAr4FL6Ov7:22 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Sep 03, 2019 at 11:10:38PM -0700, Christoph Hellwig wrote: > > + * Note that SYNCING|IOABORT is a valid state so we cannot just check for > > + * ic_state == SYNCING. > > I've removed the IOABORT flag recently, but it seems I forgot to remove > this comment. I think the comment is still relevant for SYNCING|IOERROR state, so I s/ABORT/ERROR/ > That beeing said the IOERR flag is still a complete mess > as we sometimes use it as a flag and sometimes as a separate state. > I've been wanting to sort that out, but always got preempted. Yes, I started cleaning that up (eg. using XLOG_FORCED_SHUTDOWN instead of checking the IOERROR state of the first iclog for shutdown) but it's not that simple unfortunately - it's a bit of a mess - and so I dropped that from the series to get the fixes out. I have an idea of what is wrong, but it's not ready yet. > > + */ > > +static void > > +xlog_state_callback_check_state( > > + struct xlog *log, > > + int did_callbacks) > > +{ > > + struct xlog_in_core *iclog; > > + struct xlog_in_core *first_iclog; > > + > > + if (!did_callbacks) > > + return; > > + > > + first_iclog = iclog = log->l_iclog; > > I'd keep the did_callbacks check in the caller. For the non-debug case > it will be optimized away, but it saves an argument, and allows > initializing the iclog variables on the declaration line. Fixed. FWIW, I started cleaning that up to with xlog_for_each_iclog() for all the places where we iterate like this. But that's also dependent on the IOERROR cleanup I shelved for the moment.... > > + do { > > + ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK); > > + /* > > + * Terminate the loop if iclogs are found in states > > + * which will cause other threads to clean up iclogs. > > + * > > + * SYNCING - i/o completion will go through logs > > + * DONE_SYNC - interrupt thread should be waiting for > > + * l_icloglock > > + * IOERROR - give up hope all ye who enter here > > + */ > > + if (iclog->ic_state == XLOG_STATE_WANT_SYNC || > > + iclog->ic_state & XLOG_STATE_SYNCING || > > + iclog->ic_state == XLOG_STATE_DONE_SYNC || > > + iclog->ic_state == XLOG_STATE_IOERROR ) > > + break; > > + iclog = iclog->ic_next; > > No new, but if we list the states we should not miss one.. Which one if missing? Cheers, -- Dave Chinner david@fromorbit.com