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=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 412B0C433E1 for ; Thu, 27 Aug 2020 02:59:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F3F052075B for ; Thu, 27 Aug 2020 02:59:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="miLJ3Txd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F3F052075B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 562E26B0002; Wed, 26 Aug 2020 22:59:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 515386B0003; Wed, 26 Aug 2020 22:59:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 401C56B0006; Wed, 26 Aug 2020 22:59:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0110.hostedemail.com [216.40.44.110]) by kanga.kvack.org (Postfix) with ESMTP id 279A36B0002 for ; Wed, 26 Aug 2020 22:59:55 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D1561181AEF1F for ; Thu, 27 Aug 2020 02:59:54 +0000 (UTC) X-FDA: 77194843908.21.lunch38_5f0176e27069 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin21.hostedemail.com (Postfix) with ESMTP id A98CF180442C2 for ; Thu, 27 Aug 2020 02:59:54 +0000 (UTC) X-HE-Tag: lunch38_5f0176e27069 X-Filterd-Recvd-Size: 5059 Received: from mail-io1-f68.google.com (mail-io1-f68.google.com [209.85.166.68]) by imf08.hostedemail.com (Postfix) with ESMTP for ; Thu, 27 Aug 2020 02:59:54 +0000 (UTC) Received: by mail-io1-f68.google.com with SMTP id s1so4332250iot.10 for ; Wed, 26 Aug 2020 19:59:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=so9l8A4YqPXHm/BfsVqJ0qT+vESqYPxgUIFms4VihHY=; b=miLJ3TxdWtBzFcFP6l4h1cdrKFUYTg1bKrTjkBbUV4l8UFlzJ2Kc5ColaD4rWIwOuY hynwV/u/tZwKYxgA9p3Bg6kBznewcJBrlLjE5NSdkCCXDQkbiPeARRkCJZAFuq/gmvKo hTOs3/qaNJurMR0PrEiJRL1VPdvXDKOwC0F+bAzsadbhI8xYcF4psb5w//+8jIsxrAWt gW4G42HFqixREoJu1KJWi+5G8X6lNYb1os4azkyskdjHwFcBBb2IbbNtzbL/PWirorAy 36aqr4GQYg7NNoyXrFNJK5mm5wN8wa4mC7iASxQzXkp3rh89H16JsiHZK5fVHVlNE5Bf oS9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=so9l8A4YqPXHm/BfsVqJ0qT+vESqYPxgUIFms4VihHY=; b=eRL7fd8kvB/PZR8bm7apjP+DpZaiGd2SQf+EXwjTglTNmAVn7TFDlN2gQE51/6vY0/ /6jHlyjxmeckU1nRNi5q4mfJ3Jo9UnSsClCk/E5zXS2pi3KwIKZ1zSPOuCh4XAHqi4FC OVpVYoalSUDoKNizeZMCWywmRtj48vssfYCOEraz5WdZIDA2kL1tudtnj3PCEAJhVoVQ kfc3mh3SRLPWB63W9b0FEjxTEzZRc3C80TUwMEtlJZYQKz+1fHR9yTWj9lOetRogPZ7K rWDIJBRp3pcEBM92pWPsZFMpDlC68XEVfZiCwHNc9FAlhoV5HU6IrWgN2e5WSqwWeiZX ErkQ== X-Gm-Message-State: AOAM5318G0NytZZqVbhF8F/USJ1Ve/lxYWtBjPE0sy56DM4GbjJ7duS8 gkX6Prtj4ffNDkJj0itud747A3Dtco8DbkpvRMQ= X-Google-Smtp-Source: ABdhPJxdYDdW3vnfKYKnLIYpTXu6fth4mk6UmXCLurNLOw74xNiESboAi1oO51pwWDYByCnacffl88ypXCRb+NJCaoE= X-Received: by 2002:a05:6602:26c1:: with SMTP id g1mr15642398ioo.10.1598497193630; Wed, 26 Aug 2020 19:59:53 -0700 (PDT) MIME-Version: 1.0 References: <20200827013444.24270-1-laoar.shao@gmail.com> <20200827013444.24270-3-laoar.shao@gmail.com> <20200827015853.GA14765@casper.infradead.org> <20200827024248.GA12131@dread.disaster.area> In-Reply-To: <20200827024248.GA12131@dread.disaster.area> From: Yafang Shao Date: Thu, 27 Aug 2020 10:59:17 +0800 Message-ID: Subject: Re: [PATCH v7 2/2] xfs: avoid transaction reservation recursion To: Dave Chinner Cc: Matthew Wilcox , Christoph Hellwig , "Darrick J. Wong" , Michal Hocko , Andrew Morton , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Linux MM Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: A98CF180442C2 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Aug 27, 2020 at 10:42 AM Dave Chinner wrote: > > On Thu, Aug 27, 2020 at 10:13:15AM +0800, Yafang Shao wrote: > > On Thu, Aug 27, 2020 at 9:58 AM Matthew Wilcox wrote: > > > > > > On Thu, Aug 27, 2020 at 09:34:44AM +0800, Yafang Shao wrote: > > > > @@ -1500,9 +1500,9 @@ iomap_do_writepage(struct page *page, struct writeback_control *wbc, void *data) > > > > > > > > /* > > > > * Given that we do not allow direct reclaim to call us, we should > > > > - * never be called in a recursive filesystem reclaim context. > > > > + * never be called while in a filesystem transaction. > > > > */ > > > > - if (WARN_ON_ONCE(current->flags & PF_MEMALLOC_NOFS)) > > > > + if (WARN_ON_ONCE(wbc->fstrans_recursion)) > > > > goto redirty; > > > > > > Erm, Dave said: > > > > > > > I think we should just remove > > > > the check completely from iomap_writepage() and move it up into > > > > xfs_vm_writepage() and xfs_vm_writepages(). > > > > > > ie everywhere you set this new bit, just check current->journal_info. > > > > > > I can't get you. Would you pls. be more specific ? > > > > I move the check of current->journal into xfs_vm_writepage() and > > xfs_vm_writepages(), and I think that is the easiest way to implement > > it. > > > > /* we abort the update if there was an IO error */ > > @@ -564,6 +565,9 @@ xfs_vm_writepage( > > { > > struct xfs_writepage_ctx wpc = { }; > > > > + if (xfs_trans_context_active()) > > + wbc->fstrans_recursion = 1; <<< set for XFS only. > > + > > return iomap_writepage(page, wbc, &wpc.ctx, &xfs_writeback_ops); > > Get rid of wbc->fstrans_recursion. Just do > > if (WARN_ON_ONCE(current->journal_info)) > ..... > > right here in the XFS code. > Understood. But we have to implement the 'redirty' as well in the XFS code, that may make the implementation more complicated. -- Thanks Yafang