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Date: Fri, 09 Oct 2026 10:04:16 -1000
Message-ID: <871113fbf23f16c8b291bbb06e9d6f36@kernel.org>
From: Tejun Heo <tj@kernel.org>
To: Andrea Righi <arighi@nvidia.com>
Cc: sched-ext@lists.linux.dev, David Vernet <void@manifault.com>,
	Changwoo Min <changwoo@igalia.com>, Emil Tsalapatis <emil@etsalapatis.com>,
	David Dai <david.dai@linux.dev>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] sched_ext: scx_qmap: Reset a child's cpuperf targets
 once its PERF revoke takes effect
In-Reply-To: <asjNo3JmkmeTK8dr@gpd4>
References: <20261008093228.2015427-1-tj@kernel.org>
 <20261008093228.2015427-3-tj@kernel.org>
 <asjNo3JmkmeTK8dr@gpd4>
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Hello, Andrea.

On Fri, Oct 09, 2026 at 01:18:59PM +0200, Andrea Righi wrote:
> qa.rr_cids covers the entire shared pool, regardless of its current holder,
> right? If child A detaches during child B's turn, this resets the pool's cpuperf
> target even if B still holds PERF and has written its own target.
>
> Should we avoid resetting the current holder's target here?

Right. It's transient, the detach's repartition revokes the pool from B and
the handler resets it again when that lands, but B's targets get clobbered
in between. Will skip the pool when another child holds it in the next
version.

Thanks.

--
tejun