From nobody Tue Apr 7 16:29:58 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 421D8ECAAD2 for ; Fri, 26 Aug 2022 08:00:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343506AbiHZH76 (ORCPT ); Fri, 26 Aug 2022 03:59:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343499AbiHZH7y (ORCPT ); Fri, 26 Aug 2022 03:59:54 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 543D9B7E8 for ; Fri, 26 Aug 2022 00:59:52 -0700 (PDT) Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.55]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4MDXJJ3g7WzGpj0; Fri, 26 Aug 2022 15:58:08 +0800 (CST) Received: from kwepemm600008.china.huawei.com (7.193.23.88) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 15:59:50 +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; Fri, 26 Aug 2022 15:59:49 +0800 From: Shang XiaoJing To: , , , , , , , , , , CC: Subject: [PATCH -next v2] sched/deadline: Add dl_task_is_earliest_deadline helper Date: Fri, 26 Aug 2022 16:34:53 +0800 Message-ID: <20220826083453.698-1-shangxiaojing@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.175.100.227] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) 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" Wrap repeated code in helper function dl_task_is_earliest_deadline, which return true if there is no deadline task on the rq at all, or task's deadline earlier than the whole rq. Signed-off-by: Shang XiaoJing Reviewed-by: Daniel Bristot de Oliveira --- changes in v2: - pick a more descriptive function name rather than compare_task_rq. --- kernel/sched/deadline.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index d116d2b9d2f9..34271aff4712 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1810,6 +1810,14 @@ static void yield_task_dl(struct rq *rq) =20 #ifdef CONFIG_SMP =20 +static inline bool dl_task_is_earliest_deadline(struct task_struct *p, + struct rq *rq) +{ + return (!rq->dl.dl_nr_running || + dl_time_before(p->dl.deadline, + rq->dl.earliest_dl.curr)); +} + static int find_later_rq(struct task_struct *task); =20 static int @@ -1852,9 +1860,7 @@ select_task_rq_dl(struct task_struct *p, int cpu, int= flags) int target =3D find_later_rq(p); =20 if (target !=3D -1 && - (dl_time_before(p->dl.deadline, - cpu_rq(target)->dl.earliest_dl.curr) || - (cpu_rq(target)->dl.dl_nr_running =3D=3D 0))) + dl_task_is_earliest_deadline(p, cpu_rq(target))) cpu =3D target; } rcu_read_unlock(); @@ -2221,9 +2227,7 @@ static struct rq *find_lock_later_rq(struct task_stru= ct *task, struct rq *rq) =20 later_rq =3D cpu_rq(cpu); =20 - if (later_rq->dl.dl_nr_running && - !dl_time_before(task->dl.deadline, - later_rq->dl.earliest_dl.curr)) { + if (!dl_task_is_earliest_deadline(task, later_rq)) { /* * Target rq has tasks of equal or earlier deadline, * retrying does not release any lock and is unlikely @@ -2251,9 +2255,7 @@ static struct rq *find_lock_later_rq(struct task_stru= ct *task, struct rq *rq) * its earliest one has a later deadline than our * task, the rq is a good one. */ - if (!later_rq->dl.dl_nr_running || - dl_time_before(task->dl.deadline, - later_rq->dl.earliest_dl.curr)) + if (dl_task_is_earliest_deadline(task, later_rq)) break; =20 /* Otherwise we try again. */ @@ -2424,9 +2426,7 @@ static void pull_dl_task(struct rq *this_rq) * - it will preempt the last one we pulled (if any). */ if (p && dl_time_before(p->dl.deadline, dmin) && - (!this_rq->dl.dl_nr_running || - dl_time_before(p->dl.deadline, - this_rq->dl.earliest_dl.curr))) { + dl_task_is_earliest_deadline(p, this_rq)) { WARN_ON(p =3D=3D src_rq->curr); WARN_ON(!task_on_rq_queued(p)); =20 --=20 2.17.1