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=-12.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 32AB3C4361B for ; Thu, 10 Dec 2020 12:55:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F24A723D39 for ; Thu, 10 Dec 2020 12:55:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729976AbgLJMzg (ORCPT ); Thu, 10 Dec 2020 07:55:36 -0500 Received: from mout.gmx.net ([212.227.17.21]:32893 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387752AbgLJMzW (ORCPT ); Thu, 10 Dec 2020 07:55:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1607604823; bh=UwcNqCMAvPQOYt8vb47at5tPZ57mHrOfPNHyHZS5/4A=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=MIgM82b8c326cNMB1FHbOypJnuw1n5YdG1Q4kMtYNFo88p3Od1npADwu2KrKA6SEf n2KX6K2axHb+wgyohUSYlRk1FYw1n9zbXSIpVEmUSyuDL+uJmlyRxqSQ/ygRf7r39b 3AvjnrtyUWoZHGMMbzpMk9uVankQLZibMh9VdMaE= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.com (mrgmx104 [212.227.17.174]) with ESMTPSA (Nemesis) id 1N2Dx8-1k8Kev0WA2-013hI4; Thu, 10 Dec 2020 13:53:43 +0100 Subject: Re: [PATCH v2 02/18] btrfs: extent_io: refactor __extent_writepage_io() to improve readability To: Nikolay Borisov , Qu Wenruo , linux-btrfs@vger.kernel.org References: <20201210063905.75727-1-wqu@suse.com> <20201210063905.75727-3-wqu@suse.com> From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: Date: Thu, 10 Dec 2020 20:53:40 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:VjaQ5nhzInVuiJd8IV5UpNK5cffBEAg3hXRUXbqDKyoQfM1GXAK ndncpMCqDQRWb/xF7x4xB44TUgjtIt5dBUUsHYf4Mc5PhAmsfxKhFupoZN0maE+GBga4EqA uYBp8ZY8+XlgX/R4OVmkBR0bWnEU6ftkKPlf1y08ITuTg2e/8MryMUuTdsC9VJoM04ySeXG SBZEux78fQU/T7UaoEZoQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:F60qz2lFacE=:21EHF7AGOh4uJPzvFuZrBy 8a4VZYi6Pui9mz4zoHd3TurhjJG73E73JBvU/SWzeGD/idOVQbuqgQf0AXp9i0kLsGHKRfD3/ KpyNWagmnjCMRJ2FlLG9YgmH3UAC4sW6BJrJ1Ff56bqOxb1dUL4xw7oHjiDnNkKSVaxh7Eh0s jX3/RuDFq1v+Px050d01B60qHIg7EyFWe4wq3olySzaMvT/TskePpP5OrDxkKs9XCrTE2V6ew H/x7ZYCm7DVNgmU+c/eRptYkWugS67EhQE19ufRlKEB7YG+/1fPuE/NfVxxY67pgXUiHBRfz4 0tJG8RIAFcIwJ+L1+VB10DWPw+DV2QXyNygOeaRKob9U0ud0+d6W1ZQJxjj0ibXF3qupjlHH+ kqsjehQPSllD75Eq6ZtcrTX+5ZEQqihMuKeoCr0PCtVbKAx53t3T6hJRWCZelZ7WVsvg0cYPm r9HF5fxwzszQr0wFtq8q8MjMaYYml7wxMTQ0+e+D5dJ21RXKIlwK06ygY91Z7qAsNVkhfJOo8 j59Hg6IKWn1Yg9gzng7Q6a302ksgsa4mmGhvS2u2H/OXPkcWypIkdQ8qI9aD7OV0QP/8SDg+f cdj0GtzTgYJppz/7BEQByHXIFOYlD0MC0tzAnkZJyfh7GXWglZU3Khy6a62AHVU5eEPlirCFh TUn1uaFNBqy3ewRw+nMS/tO4Opx0vv9Ptek/eXZxg7uABCkgUL/3ib20Bjn5AapihUfkTQWSh rFZb6xR9edKi3CwCwHF165BN58rrFnLBrT8djmeoPXyqIpGw332Rla9Te7qCE1YBY5LRZAQRO AMryFegoaM3hPvhaTPZiYxt0k5pdm0vcOeetP6Qny95hQoU8N+L0+P0omR76xBKPYvy2pF49i RPdGXF6GPwPwic3ActcQ== Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2020/12/10 =E4=B8=8B=E5=8D=888:12, Nikolay Borisov wrote: > > > On 10.12.20 =D0=B3. 8:38 =D1=87., Qu Wenruo wrote: >> The refactor involves the following modifications: >> - iosize alignment >> In fact we don't really need to manually do alignment at all. >> All extent maps should already be aligned, thus basic ASSERT() check >> would be enough. >> >> - redundant variables >> We have extra variable like blocksize/pg_offset/end. >> They are all unnecessary. >> >> @blocksize can be replaced by sectorsize size directly, and it's only >> used to verify the em start/size is aligned. >> >> @pg_offset can be easily calculated using @cur and page_offset(page). >> >> @end is just assigned to @page_end and never modified, use @page_end >> to replace it. >> >> - remove some BUG_ON()s >> The BUG_ON()s are for extent map, which we have tree-checker to check >> on-disk extent data item and runtime check. >> ASSERT() should be enough. >> >> Signed-off-by: Qu Wenruo >> --- >> fs/btrfs/extent_io.c | 37 +++++++++++++++++-------------------- >> 1 file changed, 17 insertions(+), 20 deletions(-) >> >> diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c >> index 2650e8720394..612fe60b367e 100644 >> --- a/fs/btrfs/extent_io.c >> +++ b/fs/btrfs/extent_io.c >> @@ -3515,17 +3515,14 @@ static noinline_for_stack int __extent_writepag= e_io(struct btrfs_inode *inode, >> unsigned long nr_written, >> int *nr_ret) >> { >> + struct btrfs_fs_info *fs_info =3D inode->root->fs_info; >> struct extent_io_tree *tree =3D &inode->io_tree; >> u64 start =3D page_offset(page); >> u64 page_end =3D start + PAGE_SIZE - 1; > > nit: page_end should be renamed to end because start now points to the > logical logical byte offset, i.e having "page" in the name is misleading= . But page_offset() along page_end is still logical bytenr, thus I didn't see much confusion here... Thanks, Qu > > >