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 AB94FC433E4 for ; Tue, 25 Aug 2020 01:40:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A03C208E4 for ; Tue, 25 Aug 2020 01:40:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qVYjfvfG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725947AbgHYBkC (ORCPT ); Mon, 24 Aug 2020 21:40:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725838AbgHYBkB (ORCPT ); Mon, 24 Aug 2020 21:40:01 -0400 Received: from mail-il1-x142.google.com (mail-il1-x142.google.com [IPv6:2607:f8b0:4864:20::142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7352C061574; Mon, 24 Aug 2020 18:40:01 -0700 (PDT) Received: by mail-il1-x142.google.com with SMTP id v2so9076045ilq.4; Mon, 24 Aug 2020 18:40:01 -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=yoiR+v9rO+JXIM35TpzuNUweu/a+mWGhR08Sf+gYpoE=; b=qVYjfvfGCAzq+gxatqSrfaeQ96FYChxURcFFoBc5HXjiJqoVg5Tdqs/0vFBZ5YSE/2 SE8aSLz2Cchy9al8OyFoMCAAgxuxkx/rG6U5R57KMI1JZK2vEb/CVOCC0c/VouiJsZST X9XuB47UsC4YojWP1A8+VcjPJs7w0c87sAn5iReaKh/H8eq0fGO0gLQI/VC33M61CDSN qKFLKg/JSDmdiYE4dp0TmJBQMd20UejWs28TkVjF5FpBTp6LAPeiJVEnxmLYkMioUVTP qWqHv22buV1/cxcPf+LLRnEBy48+coznSzonwcYoMeJbmVDpCWZc+KNd92zPM08/ihAy bI0g== 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=yoiR+v9rO+JXIM35TpzuNUweu/a+mWGhR08Sf+gYpoE=; b=KeceSB6E4/WxpjX68AdhFvfWbTSmaqvCFapDW2y+cwUSH8QNk9gdkKwSnWkh75CG4G pT+5jITmOih+bH3RCEJWA7MIBLQ/jIwommcYmHaMCo8vReClgG/kS1p8+HViUBXPHnjq DJtjhriQsvUr7dEwCNgA0SGk3Qt1tFL180QcZzQ1m7pLBIxmDJRMoWZpid6XBc95CpLV MR2nHkboW4m1FJ9pPK34ntXnrNBTjrDPvA2wA5MYn4tqxabSW/SwKyZGDtSsl+qvlrTc tKrPoacciet1R60e8z0q0f3PXBt+9GDBOutg1QRP2MCSogJfXaDETzWSpKnuh23YRy2h 4rIg== X-Gm-Message-State: AOAM530R6q67/XNMMQV79nsF+T9PEmgrPvCr31c9vuVngvh9iIwR6ZiI Us5IaMgTf2Vgu7dRZPmn6BwyQOrPmua99rNZ9sM= X-Google-Smtp-Source: ABdhPJx0GCQd+VH/ciHeUEmZwX5OFuSMWk4a0K8nSG9UO2gwrrUAyTwcH+dYnw1X5Jf4O6U8fviHxbX6S9C4HsipWbk= X-Received: by 2002:a92:108:: with SMTP id 8mr7376238ilb.142.1598319600842; Mon, 24 Aug 2020 18:40:00 -0700 (PDT) MIME-Version: 1.0 References: <20200824014234.7109-1-laoar.shao@gmail.com> <20200824014234.7109-3-laoar.shao@gmail.com> <20200824130925.a3d2d2b75ac3a6b4eba72fb9@linux-foundation.org> <20200824205647.GG17456@casper.infradead.org> In-Reply-To: <20200824205647.GG17456@casper.infradead.org> From: Yafang Shao Date: Tue, 25 Aug 2020 09:39:25 +0800 Message-ID: Subject: Re: [PATCH v6 2/2] xfs: avoid transaction reservation recursion To: Matthew Wilcox Cc: Andrew Morton , Dave Chinner , Christoph Hellwig , "Darrick J. Wong" , Michal Hocko , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Linux MM Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Aug 25, 2020 at 4:56 AM Matthew Wilcox wrote: > > On Mon, Aug 24, 2020 at 01:09:25PM -0700, Andrew Morton wrote: > > On Mon, 24 Aug 2020 09:42:34 +0800 Yafang Shao wrote: > > > > > --- a/include/linux/iomap.h > > > +++ b/include/linux/iomap.h > > > @@ -271,4 +271,11 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, > > > # define iomap_swapfile_activate(sis, swapfile, pagespan, ops) (-EIO) > > > #endif /* CONFIG_SWAP */ > > > > > > +/* Use the journal_info to indicate current is in a transaction */ > > > +static inline bool > > > +fstrans_context_active(void) > > > +{ > > > + return current->journal_info != NULL; > > > +} > > > > Why choose iomap.h for this? > > Because it gets used in iomap/buffered-io.c > > I don't think this is necessarily a useful abstraction, to be honest. > I'd just open-code 'if (current->journal_info)' or !current->journal_info, > whichever way round the code is: > > fs/btrfs/delalloc-space.c: if (current->journal_info) > fs/ceph/xattr.c: if (current->journal_info) { > fs/gfs2/bmap.c: if (current->journal_info) { > fs/jbd2/transaction.c: if (WARN_ON(current->journal_info)) { > fs/reiserfs/super.c: if (!current->journal_info) { > > (to pluck a few examples from existing filesystems) Make sense to me. I will update it in the next version. -- Thanks Yafang