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Subject: Re: [PATCH 02/19] sched/numa: Evaluate move once per node
From: Rik van Riel <riel@surriel.com>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
        Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Mel Gorman <mgorman@techsingularity.net>,
        Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 04 Jun 2018 10:51:27 -0400
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On Mon, 2018-06-04 at 15:30 +0530, Srikar Dronamraju wrote:

> @@ -1564,97 +1563,73 @@ static void task_numa_compare(struct
> task_numa_env *env,
>  	if (cur =3D=3D env->p)
>  		goto unlock;
> =20
> +	if (!cur) {
> +		if (!move || imp <=3D env->best_imp)
> +			goto unlock;
> +		else
> +			goto assign;
> +	}

Just bike shedding, but it may be easier to read
if the "we found our destination" check were written
more explicitly:


	if (!cur) {
		if (move && imp > env->best_imp)
			gote assign;
		else
			goto unlock;
	}

Also, the "move" variable seems to indicate that
the NUMA code may move the task, but not a decision
that moving the task is better than a swap.

Would it make sense to call it "maymove"?

I like how this patch simplifies the code a little.

--=20
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