From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-110.mta1.migadu.com [95.215.58.110]) (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 8882E379C50 for ; Wed, 30 Sep 2026 04:12:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.110 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790741542; cv=none; b=TsT7kCi8kJP10oEFeSAI+w/dz3YMOcNg8Q3WobFwT4LsnshXB1QcaHehfQsknWq+UhKobnKyaQ4I1CDEPzGdvxgOWQbfvhUMHAtvYioJD/2vocnlyshQBz80eLbGJ+QhwC1pxjGWH6PPA7OL82sOWLc8xop5Q9cGdUrZ0uEbAEo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790741542; c=relaxed/simple; bh=5ZodmMk5mazCcATEXU3st4ZtMCZZcl1LFNQi48kL3+c=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=HO7wAHMYUrSA6U5K63Nt12BeElQc5amr2j4mpGfkwAsr2GC7t0zYBIS+1tv40dYt5oY18P9xF2LKXuUqM6P/JMZTVKVhaaT2SSdfgCThThe6MSHHSC3lDYQsAORzpXVGiL88IuhR32YuHky0TX6MT1u4doAwYwDuCQiCYJrYNCo= 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=HiODBe9H; arc=none smtp.client-ip=95.215.58.110 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="HiODBe9H" X-Envelope-To: cgroups@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=5ZodmMk5mazCcATEXU3st4ZtMCZZcl1LFNQi48kL3+c=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790741537; v=1; x=1791346337; b=HiODBe9HJYSiStjIaj0hKbWEyCJHh2u7tZa3Sy5HEHm61R7IQSiGrQ3mSNfRPDkakKiNXhUy JC/6NYE9rgobU5kOYroEBvdFT+ardKefMXCg5ge7Qi/MGKQGBVg6D34YjixFFVXkQKWkF9Tn3sT EdRAj5dmvG3ibtbLXaTKc6/8= X-Envelope-To: cgroups@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 8e53c0bfa2c49de2; Wed, 30 Sep 2026 04:12:17 +0000 X-Mizu-Trace-ID: 8e53c0bfa2c49de2 X-Migadu-Flow: FLOW_OUT Message-ID: <693c4abd-e074-463d-a859-ac8033982c81@linux.dev> Date: Wed, 30 Sep 2026 12:09:39 +0800 Precedence: bulk X-Mailing-List: cgroups@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 v7 0/4] blk-iocost: BPF struct_ops cost model To: Tejun Heo References: <20260924054549.2271705-1-cui.tao@linux.dev> <6f80eca83c87b60398110c3a6d735aec@kernel.org> <4f1571a1-7e56-4264-aa7f-8dce32931ddb@linux.dev> <44f02289433805946d1e3272f626a925@kernel.org> From: Tao Cui In-Reply-To: <44f02289433805946d1e3272f626a925@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello, Tejun. 在 2026/9/30 00:27, Tejun Heo 写道: > Hello, Tao. > > On Tue, 29 Sep 2026 21:39:00 +0800, Tao Cui wrote: >> To make sure I understood correctly: attaching switches the active >> model to the attached BPF model, while model=linear and model=bpf >> only switch between the attached model and the builtin model without >> affecting the attachment itself. The attachment survives enable=0, >> and only .unreg removes it. Please shout if I still got that wrong. > > Yes, except that removing the device also removes the attachment, as > ioc_rqos_exit() ejects the model. > Thanks for confirming. I had left out the device removal case in the summary. v8 keeps the attachment independent from controller state and model selection; only .unreg and device removal (where ioc_rqos_exit() ejects the model) remove the attachment. Thanks. Tao> Thanks. > > -- > tejun