From mboxrd@z Thu Jan 1 00:00:00 1970 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 A906FE95A8E for ; Mon, 9 Oct 2023 11:13:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346192AbjJILNc (ORCPT ); Mon, 9 Oct 2023 07:13:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346139AbjJILNb (ORCPT ); Mon, 9 Oct 2023 07:13:31 -0400 Received: from out-202.mta0.migadu.com (out-202.mta0.migadu.com [91.218.175.202]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C44B94 for ; Mon, 9 Oct 2023 04:13:30 -0700 (PDT) Message-ID: <5a3342ef-f14f-173c-630f-6b474bded257@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1696850008; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6bujvWT1GknYcY3g+1JFcsWNbwZNp5LaRrzpNwllk3A=; b=wLkUIYxmmn6cmeSEYoCHAKeBvBQK14NDRGt9x2Qs/LQkAGw12ppUiQDu4TIdxvqjvl92Yw bQdY16/YjA9VxyQeH3tXV42nghOY5yuae7RD/CAEjrOV1A+oWhkpEx2mDTBocPO4NjAHkq tPWvUVo4OVfaO9xKrpZyytyWdqklQXE= Date: Mon, 9 Oct 2023 19:13:18 +0800 MIME-Version: 1.0 Subject: Re: [PATCH 2/2] sched/rt: Move sched_rt_entity::back to under the CONFIG_RT_GROUP_SCHED block Content-Language: en-US To: Ingo Molnar Cc: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, linux-kernel@vger.kernel.org References: <20231005162317.3343678-1-yajun.deng@linux.dev> <20231005162317.3343678-3-yajun.deng@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yajun Deng In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023/10/9 18:16, Ingo Molnar wrote: > * Yajun Deng wrote: > >> The member back in struct sched_rt_entity only related to RT_GROUP_SCHED, >> So move sched_rt_entity::back to under the CONFIG_RT_GROUP_SCHED block. It >> will save a few bytes. >> >> Also, init child when parent isn't NULL in init_tg_rt_entry(). >> >> Signed-off-by: Yajun Deng >> --- >> include/linux/sched.h | 2 +- >> kernel/sched/rt.c | 18 +++++++++--------- >> 2 files changed, 10 insertions(+), 10 deletions(-) >> >> diff --git a/include/linux/sched.h b/include/linux/sched.h >> index 292c31697248..d0fe56603e60 100644 >> --- a/include/linux/sched.h >> +++ b/include/linux/sched.h >> @@ -597,8 +597,8 @@ struct sched_rt_entity { >> unsigned short on_rq; >> unsigned short on_list; >> >> - struct sched_rt_entity *back; >> #ifdef CONFIG_RT_GROUP_SCHED >> + struct sched_rt_entity *back; >> struct sched_rt_entity *parent; >> /* rq on which this entity is (to be) queued: */ >> struct rt_rq *rt_rq; > Title claims this change - the rest of the changes should be in a separate > patch: Okay. I will send v2. >> diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c >> index 642edbd24ffb..7b3105b875f1 100644 >> --- a/kernel/sched/rt.c >> +++ b/kernel/sched/rt.c >> @@ -233,8 +233,10 @@ void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, >> >> if (!parent) >> rt_se->rt_rq = &rq->rt; >> - else >> + else { >> rt_se->rt_rq = parent->my_q; >> + parent->back = rt_se; >> + } >> >> rt_se->my_q = rt_rq; >> rt_se->parent = parent; >> @@ -1441,23 +1443,21 @@ static void __dequeue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flag >> */ >> static void dequeue_rt_stack(struct sched_rt_entity *rt_se, unsigned int flags) >> { >> - struct sched_rt_entity *back = NULL; >> + struct sched_rt_entity *root = NULL; >> unsigned int rt_nr_running; >> >> - for_each_sched_rt_entity(rt_se) { >> - rt_se->back = back; >> - back = rt_se; >> - } >> + for_each_sched_rt_entity(rt_se) >> + root = rt_se; >> >> - rt_nr_running = rt_rq_of_se(back)->rt_nr_running; >> + rt_nr_running = rt_rq_of_se(root)->rt_nr_running; >> >> - rt_se = back; >> + rt_se = root; >> for_each_sched_rt_entity_back(rt_se) { >> if (on_rt_rq(rt_se)) >> __dequeue_rt_entity(rt_se, flags); >> } >> >> - dequeue_top_rt_rq(rt_rq_of_se(back), rt_nr_running); >> + dequeue_top_rt_rq(rt_rq_of_se(root), rt_nr_running); >> } >> >> static void enqueue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags) >> -- >> 2.25.1 > Thanks, > > Ingo