Re: cpu.stat in core or cpu controller (was Re: [RFC PATCH v2] cgroup: Track time in cgroup v2 freezer)

[Chen Ridong]

On 2025/7/25 9:08, Tejun Heo wrote:
> On Wed, Jul 23, 2025 at 09:28:02AM +0800, Chen Ridong wrote:
>>> But beware that the possibility of having cpu.stat without enabling the
>>> cpu controller on v2 is a user visible behavior and I'm quite sure some
>>> userspace relies on it, so you'd need to preserve that.
>>
>> This is what I worry about. Thank you for your confirmation.
> 
> Yeah, this was an intentional decision - sacrificing a bit of code org
> cleanliness for everyday usefulness. Enabling CPU controller can have
> substantial overhead and having cpu stats available by default doesn't cost
> much while improving usefulness.
> 
> Thanks.
> 

Thank you Tj, This is clear now.

Best regards,
Ridong