From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.76 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793270000; b=XcHn1rSV4RYaj6Vu16hd6mdEqOT47AaReanzAuWChvK738f/XeAvqd0p37f1G5m8Elzi 2XU1iepgHOBwM//hnENj/ZNqctj0F7vXTgNCb2MyDSn+SB7SIRncAqKiRsHZSvoDG+Che v7RAgW7Z7dEWb8emfKE44p+ZdBreWL7KBer9rN+UifW0oJPTnzWLRYB+tSOFHd3ycW95j sBanjaGtw7WdJQbFtTPPvuqOAOO+hRvwRZJfL3odvhCfhrAsKIIcAP+hq6edsuNLnAJFf aTMgG53eAogluCnYKx+SrkgeCHqUl2CkiAWWMNkfQJYAnenVDfJ1CwurmogpEH782SA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793270000; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Message-ID:Date:MIME-Version:User-Agent: Cc:Subject:To:References:From:In-Reply-To:Content-Type: Content-Transfer-Encoding; bh=AQbbcg15G9Rdgl9nUgK2PYtfP3hcLsC+WTRWlyTICwA=; b=2BVb86xK9swe8C+WIOwuhrALJYEzzZ5XJakbmPddJtHCPVF9vF7VtAx+e2cZyRl10EFg KzGTZ314/KWzgCFCrGoTUILyU39pVfy/Tt7VDrbHfP1jA+rVQeFsmS12CrgQP0qO20BOq LxZX5OPULcuJHBhEfiYAZR/a9utLRbTB3Z91ornpWVHyD8NjBAaegsQE8mDeZeTfBOB2u CB17ZL6yYDBsXwEboj1L5FDxp3YI9X+ynRkD7qzaZIEIton0nDftzfsaedaNomeuyfXNx RwJ8mzN1VXjmVMcJdM/v+IPpK4hn8vzQV5fPB74bPWhsw5yHj/Ue8lyC2yeWP46wrVw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=VcAcw2Oh; arc=none smtp.remote-ip=91.218.175.76 Received: from mta0.migadu.com (out-76.mta0.migadu.com [91.218.175.76]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A54B5606A31A for ; Thu, 29 Oct 2026 10:33:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org A54B5606A31A 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, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=VcAcw2Oh X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=J85rkoN1XnhCBt+ZBRQtQySMprDThVLpEudrWZLX1rQ=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793269997; v=1; x=1793874797; b=VcAcw2OhNb8Ngx6ElwFkLwLvwMVCY+eOq9jXaMCps/cuSKMXma2q+6gtBUpqiyDHqHWChBTN sng+jaxnGEVj+2NcVZtDgDphJmHuw8dIxMXkNJP2G5KqGsnI7dLXHHnjDFexuTJqJK/Ig+VXs6y Rf1EiBQI5fsrasMWufpxL95M= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 14e5668ba4a579be; Thu, 29 Oct 2026 10:33:17 +0000 X-Mizu-Trace-ID: 14e5668ba4a579be X-Migadu-Flow: FLOW_OUT Message-ID: Date: Thu, 29 Oct 2026 18:33:09 +0800 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list 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, cuitao@kylinos.cn, ameryhung@gmail.com, alexei.starovoitov@gmail.com Subject: Re: [PATCH 5/5] docs: cgroup-v2: document the iocost BPF cost model attachment To: Tejun Heo References: <20261028143534.135968-1-cui.tao@linux.dev> <20261028143534.135968-6-cui.tao@linux.dev> <72deb196d0dfc413a48f0739013bc610@kernel.org> From: Tao Cui In-Reply-To: <72deb196d0dfc413a48f0739013bc610@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello Tejun, 在 2026/10/29 04:09, Tejun Heo 写道: > Hello, Tao. > > On Wed, Oct 28, 2026 at 10:35:34PM +0800, Tao Cui wrote: >> + When CONFIG_BLK_CGROUP_IOCOST_BPF is enabled, a BPF cost >> + model can be bound to a device by attaching an > > Users can't select CONFIG_BLK_CGROUP_IOCOST_BPF. > The sentence now reads "When BPF cost model support is available". >> + Only detaching removes the model, after which "model=bpf" >> + fails and the device prices with the builtin model again. >> + Device removal ejects the attached model as well, while the >> + struct_ops link remains until userspace destroys it. "ctrl" > > "Only detaching removes the model" is followed by "Device removal ejects > the attached model as well". > Dropped "Only". >> + accepts only "auto" and "user" and never selects a model. It >> + keeps describing the builtin coefficients, which take effect >> + again when switched back. The automatic profile stepping does >> + not switch profiles while the BPF model is in use; as with >> + user-set parameters, the profile selected from the device >> + class still applies. > > cgroup-v2.rst doesn't describe automatic profile stepping anywhere else. > Those sentences are removed. >> + defined. They remain readable and writable while "model" is >> + "bpf" but take effect only after switching back to "linear". > > The builtin coefficients taking effect again after switching back is > already said above. > Removed. Thanks, Tao > Thanks. > > -- > tejun