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Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 12 Dec 2022 08:06:55 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Peter Zijlstra <peterz@infradead.org>
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Subject: Re: [PATCH 10/31] sched: Add @reason to
 sched_class->rq_{on|off}line()
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References: <20221130082313.3241517-1-tj@kernel.org>
 <20221130082313.3241517-11-tj@kernel.org>
 <Y5cXMMor2qZAj7Cw@hirez.programming.kicks-ass.net>
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On Mon, Dec 12, 2022 at 12:57:36PM +0100, Peter Zijlstra wrote:
> On Tue, Nov 29, 2022 at 10:22:52PM -1000, Tejun Heo wrote:
> > ->rq_{on|off}line are called either during CPU hotplug or cpuset partition
> > updates. Let's add an argument to distinguish the two cases. The argument
> > will be used by a new sched_class to track CPU hotplug events.
> 
> Again, utter lack of why.

sched_ext wants to tell the BPF scheduler about CPU hotplugs in a way that's
synchronized with rq state changes, so it needs to distinguish the two
cases. Will update the description.

Thanks.

-- 
tejun