From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 EF26F38F82; Thu, 20 Jun 2024 06:48:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718866111; cv=none; b=YZj5eTFeS3LKkuqVXQ2byKAGN0gQhry0M7lNfXWI9nwlGgDmcVjlQwQoIMQNLzSo2V8Udo3EG5kXV9ibq93x2TRt3B71MfdKGe6/jytDgARjDOYB2HF/ss8jWTEHg8eGhQp5dElDTbN+d+zRofiQw8B/hc8b84siaJH1Dyz7qWU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718866111; c=relaxed/simple; bh=EURGL1Rs3BdktP3BB0xtvce8eQsfhKCbDz44BOfgB4A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Zeziuefi+OKyBjD7Dz1huDjMmaDP+UdNMCA6eUCOjyIcdqsm8wMOwq3t6CK90LMBNLnesSYjx4/UmSn5iuzdyX3X87InLOFP6dteHuZC9RKPxmozm0HzoK+tCjqDquWHvKO18USjIJjR1M4olDoJTk53GAR69bShezcaB7TTRIc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=01ffPyud; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="01ffPyud" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=5jgpDICmScrWTrO4VPVId37Kbw6KdjAcTNIFFr+6Bgw=; b=01ffPyudzC/VgkyjmjQOPwou+s 1QzmQmXLrPXKUMSKu6oGIznZeINtfeyUrZZ2yxj9ICX9sRmgJ5ZA1HQ4I2JegSqZVxKv3Bi8nQtun 67dMzxaYV8MdzA65jPyT4mpdSVwpwmk7wnsvE5XCHCMhYkkCkls3ai/yU/hobR0FM3A6uqD4Cm/Sw Q19MzuDWeSroLcv4b47sWjTrro4U0rR2rkEkiagMWy4+86GhPlAnB/9UuyP7Q8RFYZX4eErktfVwT WmbItLm0kxVmjX4cuHu3W9diD3d13pVIOkMNi6mwNm7DzaE/jsq94oncOR4xfIg+HTkJafazdmZH9 dr4nDkCQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1sKBam-00000003r8E-17Bl; Thu, 20 Jun 2024 06:48:20 +0000 Date: Wed, 19 Jun 2024 23:48:20 -0700 From: Christoph Hellwig To: Yu Kuai Cc: Christoph Hellwig , axboe@kernel.dk, tj@kernel.org, gregkh@linuxfoundation.org, bvanassche@acm.org, josef@toxicpanda.com, lizefan.x@bytedance.com, hannes@cmpxchg.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com, "yukuai (C)" Subject: Re: [PATCH RFC v2 3/7] block: export some API Message-ID: References: <20240618031751.3470464-1-yukuai1@huaweicloud.com> <20240618031751.3470464-4-yukuai1@huaweicloud.com> <25110963-cc9e-7c9f-09b3-d57e4ce6109b@huaweicloud.com> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <25110963-cc9e-7c9f-09b3-d57e4ce6109b@huaweicloud.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Jun 18, 2024 at 03:58:54PM +0800, Yu Kuai wrote: > There is already bigger helper blkg_conf_prep() exported, as used by bfq > for a long time already, and this helper is introduced for code > optimization, as iocost configuration doesn't need to access the blkg. > > Perhaps this should be another discussion about "design mistakes", > however, I'm not sure why. :( Do you have previous discussions? blkg_conf_prep at least has some level of abstraction. But at least my conclusion is: don't make blk-iocost modular. It's far too messy to split out, and not really worth it.