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Date: Sat, 17 Oct 2026 13:35:13 -1000
Message-ID: <8cacdbb7d499b8a5eaf09d052919dc05@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 3/3] sched_ext: scx_qmap: Also re-enqueue stranded tasks
 with scx_bpf_dsq_reenq_task()
In-Reply-To: <atP_f5S5v_1V06L2@gpd4>
References: <20261017223738.993262-1-tj@kernel.org>
 <20261017223738.993262-4-tj@kernel.org>
 <atP_f5S5v_1V06L2@gpd4>
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Hello, Andrea.

On Sun, Oct 18, 2026 at 01:06:39AM +0200, Andrea Righi wrote:
> > +	if (p->pid & 1) {
>
> nit: if ((p->pid & 1) && __COMPAT_has_dsq_reenq_task())

scx_qmap is already 7.4-only. It implements ops.sub_cid_sched_updated() and
ops.sub_child_ecaps_updated(), which older kernels don't have, so it doesn't
load there anyway.

Given what qmap is used for, it'd probably make sense to rip out all the
compat stuff from it and just pair it with the latest kernel by default.

Thanks.

--
tejun