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Date: Mon, 15 Jun 2015 15:12:21 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Tejun Heo <tj@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Amir Vadai <amirv@mellanox.com>, linux-kernel@vger.kernel.org,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Subject: Re: [PATCH resend] cpumask: don't perform while loop in
 cpumask_next_and()
Message-ID: <20150615131221.GA12596@twins.programming.kicks-ass.net>
References: <1425223323-20180-1-git-send-email-sergey.senozhatsky@gmail.com>
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On Mon, Mar 02, 2015 at 12:22:03AM +0900, Sergey Senozhatsky wrote:

> +++ b/lib/cpumask.c
> @@ -37,10 +37,11 @@ EXPORT_SYMBOL(__next_cpu_nr);
>  int cpumask_next_and(int n, const struct cpumask *src1p,
>  		     const struct cpumask *src2p)
>  {
> +	struct cpumask tmp;
> +
> +	if (cpumask_and(&tmp, src1p, src2p))
> +		return cpumask_next(n, &tmp);
> +	return nr_cpu_ids;
>  }
>  EXPORT_SYMBOL(cpumask_next_and);

Just ran into this; I though we were not supposed to put cpumasks on the
stack because $BIG. ?!

explain.