From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 68F3C1946AA; Mon, 13 Oct 2025 10:24:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760351042; cv=none; b=qXkgGSETkmli8PrYdVc2VpzcKUMjS2EDosRI2sceWeOKW4bfT0yBYM4S3NCKpz+GKPPDhrl5xBRHJjfVZkaQQzX0auZ2tTtm+/4EgzC3trCzidNh3cQ49dv5UCbfKrhmfjBdvEta5ZSAmSMxKZTpodSEvXGeeD0Jlq93Qo3g4Aw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760351042; c=relaxed/simple; bh=sScV2KPZkgkriilgKwRNLZq8s377U5ASqJ8TO4hXY1g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Shsvg1ICmv24annIJMQM+M/DaDv4VLyn51sz+faTiNVe8IIZiuDsT2nGmpEqQVdnqy7qcsllJ0QyGcJ3gazBwcg92VVjqvu6kHkNerryV9GEkuF5IYJ6iSyf415iAgZMDBOWVn+uSBIknYKyjXMg5yG2zA2uDGYWoGYAh93VYz8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=jGQYorAT; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="jGQYorAT" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=rronQgbUv5ut13en00I1NEaZfei/VBBBsa8mpaTADho=; b=jGQYorATM2sK1Kuyv68u/bznPv l+ocBdoORC3jyb8z4QtmpQbiX+/G9WBwvk8WdOkUXqJtsYCQoAfSgf8PD5G2AQbJEjbkTAGP+RWWY FMp0qjjG6dIXf+FF85bsN+Pyy/UtHwMAVoDkDFa/RhYtfzouEVgyIDpA2hoFlRTx1lCb7QKui6XtF sRDSHdYBPO+XQlMRG5kkEyn6d0tzW8tcPgjhueOXpeeGTEb43RWUvt32Y3Rc4WOsKdNN7Mw5ToDeU +0+MPttubZ8Wp/LiLH1RnEd97o3bVpTxR+X6HIveCvmp4ZkHybyorIG/RtCJcie5vB0Y8q4QiNJy6 qw0FZLUg==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1v8FiW-00000004Fz5-47py; Mon, 13 Oct 2025 10:23:50 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id B2D64300169; Mon, 13 Oct 2025 12:23:47 +0200 (CEST) Date: Mon, 13 Oct 2025 12:23:47 +0200 From: Peter Zijlstra To: Dietmar Eggemann Cc: tj@kernel.org, linux-kernel@vger.kernel.org, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, longman@redhat.com, hannes@cmpxchg.org, mkoutny@suse.com, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, cgroups@vger.kernel.org, sched-ext@lists.linux.dev, liuwenfang@honor.com, tglx@linutronix.de Subject: Re: [PATCH 03/12] sched: Fold sched_class::switch{ing,ed}_{to,from}() into the change pattern Message-ID: <20251013102347.GY3419281@noisy.programming.kicks-ass.net> References: <20251006104402.946760805@infradead.org> <20251006104526.861755244@infradead.org> <02452879-8998-47e0-9679-d2ff00503901@arm.com> <20251009135408.GD4067720@noisy.programming.kicks-ass.net> <20251009140925.GD4068168@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Oct 09, 2025 at 06:50:55PM +0200, Dietmar Eggemann wrote: > Yes, but there seems to be more ... missing DEQUEUE_SAVE (a.k.a. > ENQUEUE_RESTORE) in > > enqueue_dl_entity() > > if (flags & (ENQUEUE_RESTORE|ENQUEUE_MIGRATING)) > ^^^^^^^^^^^^^^^ > ... > add_running_bw(dl_se, dl_rq) > > and > > __sched_setscheduler() > > ... > if (prev_class != next_class) > queue_flags |= DEQUEUE_CLASS; > queue_flags &= ~(DEQUEUE_SAVE | DEQUEUE_MOVE); > ^^^^^^^^^^^^ > > as well as > > sched_change_begin() > > ... > if (flags & DEQUEUE_CLASS) { > if (WARN_ON_ONCE(flags & (DEQUEUE_SAVE | DEQUEUE_MOVE))) > flags &= ~(DEQUEUE_SAVE | DEQUEUE_MOVE); > ^^^^^^^^^^^^ > Urgh.. SAVE/RESTORE while changing CLASS is so weird. But yeah, let me take that bit out for now -- I'll make a note in a comment that we should look at perhaps cleaning that up instead.