From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-198.mta0.migadu.com [91.218.175.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D6C31495539 for ; Mon, 19 Oct 2026 09:50:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.198 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792403450; cv=none; b=G4ShfLlGqtWsA/HnQerF8N2UnIBBCKEFd0O/Y6PtEZNGoNCPdzlVlCPdETor9FQvixivqGWXL8Qy/anQ5EQy/d8YSzCeT/kqBswcykE2I7qzDlsto57US5rIGp68CfSQN38k/Y7pWwdFwPM2T/qHTiJwwDB55Rmp2O/6H92ORqY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792403450; c=relaxed/simple; bh=5dg8NSvB9hFjoy54PLoUpMKB7gitIbpPU2h83kRMT2s=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=nWNTiqUTVV8eqLvwg71UpQRDfSeTgjEQjOgifzzh2DXaay/Si8cqlIfw8n5Zz/Va4umkIGyTZ3eGe6mO+Wc6CvgL8mW/JcKl02DnFvA8v8FIuCelNimYkCTuSJ4yQfEnAnimF0MofK3bcbuCt5aUayNJ7bdX9h9YBNbh3X9Jb7Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Sovzfxe0; arc=none smtp.client-ip=91.218.175.198 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Sovzfxe0" X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=5dg8NSvB9hFjoy54PLoUpMKB7gitIbpPU2h83kRMT2s=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792403446; v=1; x=1793008246; b=Sovzfxe0zRfZXnJh2soMp8JNM+dkRvWsul3dh56BXn+bh1RMfHKiV7Lahy/mx9+lLjABlgMF drMjuPXJxB1EGsqMN3K+GdWu7k028eZRP46HppLCB/YeVzaFZnOiOlVc6Ajd3yWOuZDHg0uYtMv /M28WOWew/a2FNCW2e9z40/s= X-Envelope-To: bpf@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 535a794b7b48e7a4; Mon, 19 Oct 2026 09:50:46 +0000 X-Mizu-Trace-ID: 535a794b7b48e7a4 X-Migadu-Flow: FLOW_OUT Message-ID: <2352b824-7e36-453e-b3e9-151761a352c3@linux.dev> Date: Mon, 19 Oct 2026 17:50:36 +0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: cui.tao@linux.dev, josef@toxicopanda.com, axboe@kernel.dk, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, linux-kselftest@vger.kernel.org, Tao Cui , ameryhung@gmail.com, alexei.starovoitov@gmail.com Subject: Re: [RFC PATCH v10 4/4] docs: cgroup-v2: document the iocost BPF cost model attachment To: Tejun Heo References: <20261003124045.1289305-1-cui.tao@linux.dev> <20261003124045.1289305-5-cui.tao@linux.dev> From: Tao Cui In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello Tejun, 在 2026/10/17 01:49, Tejun Heo 写道: > Hello, Tao. > > On Sat, 03 Oct 2026 20:40:45 +0800, Tao Cui wrote: >> model The cost model in use - "linear" >> + or "bpf" while the BPF model >> + is in use > > "linear" or "bpf" is enough here. > Shortened to "linear" or "bpf". >> + When CONFIG_BLK_CGROUP_IOCOST_BPF is enabled, a BPF cost model >> + can be bound to a device by attaching an "iocost_model_ops" >> + struct_ops carrying the whole disk's major:minor in its "dev" >> + member (a partition's major:minor is rejected). Attaching >> + creates the controller if needed, like an io.cost.model write >> + does, and >> + switches the device's pricing to the model; enabling and > > Attaching now also populates the device's line, so the existing sentence > saying the line is populated on the first write to "io.cost.qos" or > "io.cost.model" needs updating. The paragraph also runs 21 lines with a > leftover break after "does, and". Can it be split into three, attaching, > model= selection and detaching, and removal and ctrl? > Updated and split. The documentation now says the device's line appears on the first io.cost.qos or io.cost.model write, or when a model is attached. The same wording change also went into the io.cost.qos section. The paragraph is now split into three parts: attaching, model= selection, and detaching/removal with ctrl. The stray line break after "does, and" is gone too. Thanks, Tao > Thanks. >