Re: [RFC PATCH v10 4/4] docs: cgroup-v2: document the iocost BPF cost model attachment

From: Tao Cui

Date: Mon Oct 19 2026 - 05:50:55 EST


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.
>