Re: [PATCH 5/5] docs: cgroup-v2: document the iocost BPF cost model attachment

[Tao Cui]

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