Date: Mon, 27 Jan 2014 13:16:04 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Cc: linux-kernel@vger.kernel.org, raistlin@linux.it, juri.lelli@gmail.com,
        clark.williams@gmail.com, mingo@redhat.com, rostedt@goodmis.org
Subject: Re: [PATCH 3/3] sched: Implement task_nice and task_prio as static
 inline functions.
Message-ID: <20140127121604.GD11314@laptop.programming.kicks-ass.net>
References: <cover.1390859827.git.yangds.fnst@cn.fujitsu.com>
 <1800e6249ff54199573ea5f0aa4ec16b15bb5158.1390859827.git.yangds.fnst@cn.fujitsu.com>
 <20140127103258.GZ11314@laptop.programming.kicks-ass.net>
 <52E70362.2070207@cn.fujitsu.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <52E70362.2070207@cn.fujitsu.com>
User-Agent: Mutt/1.5.21 (2012-12-30)
Sender: linux-kernel-owner@vger.kernel.org

On Mon, Jan 27, 2014 at 08:09:54PM -0500, Dongsheng Yang wrote:
> On 01/27/2014 05:32 AM, Peter Zijlstra wrote:
> >On Mon, Jan 27, 2014 at 05:15:39PM -0500, Dongsheng Yang wrote:
> >>+/**
> >>+ * task_prio - return the priority value of a given task.
> >>+ * @p: the task in question.
> >>+ *
> >>+ * Return: The priority value as seen by users in /proc.
> >>+ * RT tasks are offset by -200. Normal tasks are centered
> >>+ * around 0, value goes from -16 to +15.
> >>+ */
> >>+static inline int task_prio(const struct task_struct *p)
> >>+{
> >>+	return p->prio - MAX_RT_PRIO;
> >>+}
> >Who would ever want to use/rely on this? It doesn't make any sense. And
> >therefore it shouldn't ever be considered time critical.
> 
> I just copy it from kernel/sched/core.c. Currently, it is used in
> fs/proc/array.c.

Just leave it there. Nobody should use this value anyhow.

> >>+/**
> >>+ * task_nice - return the nice value of a given task.
> >>+ * @p: the task in question.
> >>+ *
> >>+ * Return: The nice value [ -20 ... 0 ... 19 ].
> >>+ */
> >>+static inline int task_nice(const struct task_struct *p)
> >>+{
> >>+	return TASK_NICE(p);
> >>+}
> >Urgh, no. Just remove the macro already. Although arguably we should
> >remove ->static_prio and clean up that entire mess.
> >
> 
> Oops, sorry for the noise. I am a newbie here, could you help to point out
> that
>  which tree is the latest version for sched. Thanx :)

tip/sched/core or tip/master, but that's not the issue. There's no point
in having an inline and a macro that do the exact same thing.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/