Received-SPF: pass (google.com: domain of linux-kernel+bounces-179827-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Date: Wed, 15 May 2024 13:06:13 +0100
From: Qais Yousef <qyousef@layalina.io>
To: Phil Auld <pauld@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>,
	Juri Lelli <juri.lelli@redhat.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Jens Axboe <axboe@kernel.dk>, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	linux-mm@kvack.org
Subject: Re: [PATCH] sched/rt: Clean up usage of rt_task()
Message-ID: <20240515120613.m6ajyxyyxhat7eb5@airbuntu>
References: <20240514234112.792989-1-qyousef@layalina.io>
 <20240514235851.GA6845@lorien.usersys.redhat.com>
 <20240515083238.GA40213@noisy.programming.kicks-ass.net>
 <20240515112050.GA25724@lorien.usersys.redhat.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20240515112050.GA25724@lorien.usersys.redhat.com>

On 05/15/24 07:20, Phil Auld wrote:
> On Wed, May 15, 2024 at 10:32:38AM +0200 Peter Zijlstra wrote:
> > On Tue, May 14, 2024 at 07:58:51PM -0400, Phil Auld wrote:
> > > 
> > > Hi Qais,
> > > 
> > > On Wed, May 15, 2024 at 12:41:12AM +0100 Qais Yousef wrote:
> > > > rt_task() checks if a task has RT priority. But depends on your
> > > > dictionary, this could mean it belongs to RT class, or is a 'realtime'
> > > > task, which includes RT and DL classes.
> > > > 
> > > > Since this has caused some confusion already on discussion [1], it
> > > > seemed a clean up is due.
> > > > 
> > > > I define the usage of rt_task() to be tasks that belong to RT class.
> > > > Make sure that it returns true only for RT class and audit the users and
> > > > replace them with the new realtime_task() which returns true for RT and
> > > > DL classes - the old behavior. Introduce similar realtime_prio() to
> > > > create similar distinction to rt_prio() and update the users.
> > > 
> > > I think making the difference clear is good. However, I think rt_task() is
> > > a better name. We have dl_task() still.  And rt tasks are things managed
> > > by rt.c, basically. Not realtime.c :)  I know that doesn't work for deadline.c
> > > and dl_ but this change would be the reverse of that pattern.
> > 
> > It's going to be a mess either way around, but I think rt_task() and
> > dl_task() being distinct is more sensible than the current overlap.
> >
> 
> Yes, indeed.
> 
> My point was just to call it rt_task() still. 

It is called rt_task() still. I just added a new realtime_task() to return true
for RT and DL. rt_task() will return true only for RT now.

How do you see this should be done instead? I'm not seeing the problem.