From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [PATCH] namespace.c: fix bind mount from foreign namespace
Date: Tue, 17 May 2005 02:28:54 +0100
Message-ID: <20050517012854.GC32226@mail.shareable.org>
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Cc: linuxram@us.ibm.com, viro@parcelfarce.linux.theplanet.co.uk,
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	linux-fsdevel@vger.kernel.org
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To: Miklos Szeredi <miklos@szeredi.hu>
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Miklos Szeredi wrote:
> +		if (ns1 < ns2) {
> +			down_write(&ns1->sem);
> +			down_write(&ns2->sem);
> +		} else {
> +			down_write(&ns2->sem);
> +			down_write(&ns1->sem);
> +		}

That's a bit smaller (source and compiled) as:

	if (ns2 < ns1)
		down_write(&ns2->sem);
	down_write(&ns1->sem);
	if (ns2 > ns1)
		down_write(&ns2->sem);

(And you'll notice that does the right thing if ns2==ns1 too, in case
that gives you any ideas.)

Otherwise, the patch looks convincing to me.

-- Jamie