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 X-Spam-Level: X-Spam-Status: No, score=-11.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14A07C4727C for ; Wed, 30 Sep 2020 00:29:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A99792075A for ; Wed, 30 Sep 2020 00:29:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729126AbgI3A3U (ORCPT ); Tue, 29 Sep 2020 20:29:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:45526 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728799AbgI3A3U (ORCPT ); Tue, 29 Sep 2020 20:29:20 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6EACE2071E; Wed, 30 Sep 2020 00:29:18 +0000 (UTC) Date: Tue, 29 Sep 2020 20:29:16 -0400 From: Steven Rostedt To: Hui Su Cc: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH] sched/rt.c remove unnecessary parameter in pick_next_rt_entity Message-ID: <20200929202916.7e26f4cb@oasis.local.home> In-Reply-To: <20200929165640.GA28986@rlk> References: <20200929165640.GA28986@rlk> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 30 Sep 2020 00:56:40 +0800 Hui Su wrote: > struct rq is not necessary for pick_next_rt_entity(), > we can get next sched_rt_entity just from struct rt_rq. > > Signed-off-by: Hui Su > --- > kernel/sched/rt.c | 9 +++------ > 1 file changed, 3 insertions(+), 6 deletions(-) > > diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c > index f215eea6a966..113965e1952c 100644 > --- a/kernel/sched/rt.c > +++ b/kernel/sched/rt.c > @@ -1593,11 +1593,9 @@ static inline void set_next_task_rt(struct rq *rq, struct task_struct *p, bool f > rt_queue_push_tasks(rq); > } > > -static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq, > - struct rt_rq *rt_rq) > +static struct sched_rt_entity *pick_next_rt_entity(struct rt_rq *rt_rq) > { > struct rt_prio_array *array = &rt_rq->active; > - struct sched_rt_entity *next = NULL; > struct list_head *queue; > int idx; > > @@ -1605,9 +1603,8 @@ static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq, > BUG_ON(idx >= MAX_RT_PRIO); > > queue = array->queue + idx; > - next = list_entry(queue->next, struct sched_rt_entity, run_list); > > - return next; > + return list_entry(queue->next, struct sched_rt_entity, run_list); The above code looks to be left over from a time that there was a goto out; with out: being between the next = list_etry() and the return next. This was removed back in 2008 with commit 326587b84078 ("sched: fix goto retry in pick_next_task_rt()"). The above looks fine to me. Reviewed-by: Steven Rostedt (VMware) -- Steve > } > > static struct task_struct *_pick_next_task_rt(struct rq *rq) > @@ -1616,7 +1613,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq) > struct rt_rq *rt_rq = &rq->rt; > > do { > - rt_se = pick_next_rt_entity(rq, rt_rq); > + rt_se = pick_next_rt_entity(rt_rq); > BUG_ON(!rt_se); > rt_rq = group_rt_rq(rt_se); > } while (rt_rq);