Re: [PATCH v3] sched: cpuset: Don't rebuild root domains on suspend-resume

Waiman Long
2023-03-08T19:23:01Z

On 3/8/23 05:19, Juri Lelli wrote:
> On 01/03/23 17:03, Qais Yousef wrote:
>> On 03/01/23 15:26, Juri Lelli wrote:
>>> On 01/03/23 12:28, Qais Yousef wrote:
>>>> On 03/01/23 08:31, Juri Lelli wrote:
>>> ...
>>>
>>>>> Not ignoring you guys here, but it turns out I'm quite bogged down with
>>>>> other stuff at the moment. :/ So, apologies and I'll try to get to this
>>>>> asap. Thanks a lot for all your efforts and time reviewing so far!
>>>> Np, I can feel you :-)
>>> Eh. :/
>> I hope I did not offend. That was meant as no pressure, I understand.
> No offence at all! I meant "we are all on the same boat it seems". :)
>
>>> BTW, do you have a repro script of some sort handy I might play with?
>> Sorry no. You'll just need to suspend to ram. I had a simple patch to measure
>> the time around the call and trace_printk'ed the result.
>>
>> I was working on a android phone which just suspends to ram if you turn the
>> screen off and disconnect the usb.
> Looks like I could come up with the following
>
> https://github.com/jlelli/linux.git deadline/rework-cpusets
> https://github.com/jlelli/linux/tree/deadline/rework-cpusets
>
> which I don't think it's at a point that I feel comfortable to propose
> as an RFC (not even sure if it actually makes sense), but it survived my
> very light testing.

I like your patch to revert the cpuset_rwsem change. In fact, I was
planning to ask you about that. It is causing a lot more latency in
workloads that need to change cpuset configuration rather frequently.

Cheers,
Longman