From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B650119413B; Fri, 11 Oct 2024 08:56:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728637016; cv=none; b=PWXwwuVveH9+r1LGgUT8Ru4oettGPZ2kZy9uMRrCqCOlUjMLd5XUcVXnzYPP/Di5urqCUL3IIoecOK7TB3IIYkax9nH9EzNKwpZFj8wqWykKkylJmCK+36pFdcnd88gmHjHv1sqIL7Phj+vlXocqcI0qyNA3t/eisLH6AoO2n/A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728637016; c=relaxed/simple; bh=O8UMgy4NK3I9Ac3Z4UxYDyPfUUZlGgk3rritssUgmSE=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=tARUZFXjkRilAgHZolZI8wwyzUbDh0CI/KW8wpDk9KE24GW/KY6Jv8mHIiUtXJbigOEXUPgOzZ5zMFXvo/sVA4VwsG0QxIpFxZrsNooxoa92JsY7TxLX3YvFRvPgoPNYEILUwhSKWdT7ed0yb4tyMFWZ2zT7v/rVg++4OttSb9s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZTArbzVF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZTArbzVF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BD7DBC4CEC3; Fri, 11 Oct 2024 08:56:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728637016; bh=O8UMgy4NK3I9Ac3Z4UxYDyPfUUZlGgk3rritssUgmSE=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=ZTArbzVFqv+vzi6Ln/obGoDSQd75fU7AS/1J/rnwZ9ku7vVaqKOt4oBS7JFJl97LO yfC4gpjRIdwLUVcsR9aNXaQ6VxmcJjgqc03c2XxyAheP9pjPRqKKdIVrJRezZcmW7+ u7ukKjQBckULxox8wj4bRRfYoIAOsNmJ8L6ZPg91RV4KwaOr43dORcPYh54BY6GKfA 7jcHaXhmB6Yr6s1PdvDKz/PoD24aPBKaeXx1xn1bWJCfC7unyVJ9J60SyCACrCVTR6 7nFcVxyZz16BTAgYSUOGucG0jGiJ+vlDb+LhwhTgc1Ntryp70OhvnjbNbVa8XXHbce XYBaxpbPM8g0g== Message-ID: <94166f32-7ff9-46d2-83c9-4df2a787fe25@kernel.org> Date: Fri, 11 Oct 2024 16:56:47 +0800 Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: Chao Yu , "Pankaj Raghav (Samsung)" , Theodore Ts'o , Jonathan Corbet , Josef Bacik , Johannes Weiner , =?UTF-8?Q?Michal_Koutn=C3=BD?= , Alexander Viro , "Darrick J . Wong" , Zefan Li , Tejun Heo , akpm@linux-foundation.org, Christian Brauner , Andreas Dilger , Jan Kara , Chris Mason , David Sterba , cgroups@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, mcgrof@kernel.org, gost.dev@samsung.com, linux-doc@vger.kernel.org, linux-xfs@vger.kernel.org, Pankaj Raghav Subject: Re: [PATCH] fs/writeback: convert wbc_account_cgroup_owner to take a folio To: Matthew Wilcox , Jaegeuk Kim References: <20240926140121.203821-1-kernel@pankajraghav.com> Content-Language: en-US From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2024/10/1 6:58, Jaegeuk Kim wrote: > On 09/26, Matthew Wilcox wrote: >> On Thu, Sep 26, 2024 at 04:01:21PM +0200, Pankaj Raghav (Samsung) wrote: >>> Convert wbc_account_cgroup_owner() to take a folio instead of a page, >>> and convert all callers to pass a folio directly except f2fs. >>> >>> Convert the page to folio for all the callers from f2fs as they were the >>> only callers calling wbc_account_cgroup_owner() with a page. As f2fs is >>> already in the process of converting to folios, these call sites might >>> also soon be calling wbc_account_cgroup_owner() with a folio directly in >>> the future. >> >> I was hoping for more from f2fs. I still don't have an answer from them >> whether they're going to support large folios. There's all kinds of >> crud already in these functions like: >> >> f2fs_set_bio_crypt_ctx(bio, fio->page->mapping->host, >> page_folio(fio->page)->index, fio, GFP_NOIO); >> >> and this patch is making it worse, not better. A series of patches >> which at least started to spread folios throughout f2fs would be better. >> I think that struct f2fs_io_info should have its page converted to >> a folio, for example. Although maybe not; perhaps this structure can >> carry data which doesn't belong to a folio that came from the page cache. >> It's very hard to tell because f2fs is so mind-numbingly complex and >> riddled with stupid abstraction layers. > > Hah, I don't think it's too complex at all tho, there's a somewhat complexity to > support file-based encryption, compression, and fsverity, which are useful I agree w/ Jaegeuk. > for Android users. Well, I don't see any strong needs to support large folio, > but some requests exist which was why we had to do some conversion. > >> >> But I don't know what the f2fs maintainers have planned. And they won't >> tell me despite many times of asking. I supported large folio in f2fs by using a hacking way /w iomap fwk, it can only be enabled in very limited condition, after some seqread tests, I can see performance gain in server environment, but none in android device, and in addition, there is a memory leak bug which can cause out-of-memory issue. Unlucky, I have no slots to dig into these issues recently. Thanks,