Date:   Wed, 8 Mar 2023 11:19:06 +0100
From:   Juri Lelli <juri.lelli@redhat.com>
To:     Qais Yousef <qyousef@layalina.io>
Cc:     Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Waiman Long <longman@redhat.com>,
        Steven Rostedt <rostedt@goodmis.org>, tj@kernel.org,
        linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it,
        claudio@evidence.eu.com, tommaso.cucinotta@santannapisa.it,
        bristot@redhat.com, mathieu.poirier@linaro.org,
        cgroups@vger.kernel.org,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Wei Wang <wvw@google.com>, Rick Yiu <rickyiu@google.com>,
        Quentin Perret <qperret@google.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Sudeep Holla <sudeep.holla@arm.com>,
        Zefan Li <lizefan.x@bytedance.com>, linux-s390@vger.kernel.org,
        x86@kernel.org
Subject: Re: [PATCH v3] sched: cpuset: Don't rebuild root domains on
 suspend-resume
Message-ID: <ZAhhGi55BkYkc3ss@localhost.localdomain>
References: <20230206221428.2125324-1-qyousef@layalina.io>
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 <5f087dd8-3e39-ce83-fe24-afa5179c05d9@arm.com>
 <20230227205725.dipvh3i7dvyrv4tv@airbuntu>
 <5a1e58bf-7eb2-bd7a-7e19-7864428a2b83@arm.com>
 <20230228174627.vja5aejq27dsta2u@airbuntu>
 <Y/7/SLzvK8LfB29z@localhost.localdomain>
 <20230301122852.zgzreby42lh2zf6w@airbuntu>
 <Y/9gmDRlGOChIwpf@localhost.localdomain>
 <20230301170322.xthlso7jfkixlyex@airbuntu>
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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.

Could you please take a look and, if it makes some sense in theory, give
it a try on your end?

Thanks!
Juri