linux-kernel - RE: [PATCH v3 2/2] sched/rt: Remove unnecessary condition in push_rt

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Message-ID: <001801d28824$7f3f70f0$7dbe52d0$@lge.com>
Date:   Thu, 16 Feb 2017 16:15:47 +0900
From:   "byungchul.park" <byungchul.park@....com>
To:     <juri.lelli@...il.com>
Cc:     <peterz@...radead.org>, <mingo@...nel.org>,
        <linux-kernel@...r.kernel.org>, <kernel-team@....com>,
        "'Steven Rostedt'" <rostedt@...dmis.org>
Subject: RE: [PATCH v3 2/2] sched/rt: Remove unnecessary condition in push_rt_task()

> -----Original Message-----
> From: Steven Rostedt [mailto:rostedt@...dmis.org]
> Sent: Thursday, February 16, 2017 11:46 AM
> To: Byungchul Park
> Cc: peterz@...radead.org; mingo@...nel.org; linux-kernel@...r.kernel.org;
> juri.lelli@...il.com; kernel-team@....com
> Subject: Re: [PATCH v3 2/2] sched/rt: Remove unnecessary condition in
> push_rt_task()
> 
> On Thu, 16 Feb 2017 11:34:17 +0900
> Byungchul Park <byungchul.park@....com> wrote:
> 
> > pick_next_pushable_task(rq) has BUG_ON(rq_cpu != task_cpu(task)) when
> > it returns a task other than NULL, which means that task_cpu(task) must
> > be rq->cpu. So if task == next_task, then task_cpu(next_task) must be
> > rq->cpu as well. Remove the redundant condition and make code simpler.
> >
> > By this patch, unnecessary one branch and two LOAD operations in 'if'
> > statement can be avoided.
> >
> > Signed-off-by: Byungchul Park <byungchul.park@....com>
> > Reviewed-by: Steven Rostedt (VMware) <rostedt@...dmis.org>
> > Reviewed-by: Juri Lelli <juri.lelli@....com>
> > ---
> 
> This is a different patch, I don't believe Juri reviewed it yet.

Hello juri,

I should have asked you first and been more careful before I added
'reviewed-by'. Can I ask you for your opinion about the additional one?