From nobody Sun Apr 12 13:35:50 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B3BACECAAD4 for ; Mon, 29 Aug 2022 13:23:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229838AbiH2NXV (ORCPT ); Mon, 29 Aug 2022 09:23:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230204AbiH2NW6 (ORCPT ); Mon, 29 Aug 2022 09:22:58 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 486B015A1A for ; Mon, 29 Aug 2022 06:20:00 -0700 (PDT) Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4MGSgp4WfNznTrQ; Mon, 29 Aug 2022 19:21:42 +0800 (CST) Received: from kwepemm600008.china.huawei.com (7.193.23.88) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 29 Aug 2022 19:24:07 +0800 Received: from huawei.com (10.175.100.227) by kwepemm600008.china.huawei.com (7.193.23.88) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 29 Aug 2022 19:24:05 +0800 From: Shang XiaoJing To: , , , , , , , , , , CC: Subject: [PATCH v2] sched/deadline: Skip meaningless bw updates in dl_task_offline_migration Date: Mon, 29 Aug 2022 19:59:04 +0800 Message-ID: <20220829115904.28560-1-shangxiaojing@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.175.100.227] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemm600008.china.huawei.com (7.193.23.88) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Skip meaningless bw updates on root domain if task still stay in same rd while calling dl_task_offline_migration. Signed-off-by: Shang XiaoJing Reviewed-by: Daniel Bristot de Oliveira --- changes in v2: - fix subject and comment message --- kernel/sched/deadline.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 8e14dc21d829..9660e166c8ec 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -714,20 +714,22 @@ static struct rq *dl_task_offline_migration(struct rq= *rq, struct task_struct *p add_rq_bw(&p->dl, &later_rq->dl); } =20 - /* - * And we finally need to fixup root_domain(s) bandwidth accounting, - * since p is still hanging out in the old (now moved to default) root - * domain. - */ - dl_b =3D &rq->rd->dl_bw; - raw_spin_lock(&dl_b->lock); - __dl_sub(dl_b, p->dl.dl_bw, cpumask_weight(rq->rd->span)); - raw_spin_unlock(&dl_b->lock); + if (&rq->rd !=3D &later_rq->rd) { + /* + * And we finally need to fixup root_domain(s) bandwidth accounting, + * since p is still hanging out in the old (now moved to default) root + * domain. + */ + dl_b =3D &rq->rd->dl_bw; + raw_spin_lock(&dl_b->lock); + __dl_sub(dl_b, p->dl.dl_bw, cpumask_weight(rq->rd->span)); + raw_spin_unlock(&dl_b->lock); =20 - dl_b =3D &later_rq->rd->dl_bw; - raw_spin_lock(&dl_b->lock); - __dl_add(dl_b, p->dl.dl_bw, cpumask_weight(later_rq->rd->span)); - raw_spin_unlock(&dl_b->lock); + dl_b =3D &later_rq->rd->dl_bw; + raw_spin_lock(&dl_b->lock); + __dl_add(dl_b, p->dl.dl_bw, cpumask_weight(later_rq->rd->span)); + raw_spin_unlock(&dl_b->lock); + } =20 set_task_cpu(p, later_rq->cpu); double_unlock_balance(later_rq, rq); --=20 2.17.1