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Subject: Re: [PATCH -rt] update kmap_atomic on !HIGHMEM
From: Daniel Walker <dwalker@mvista.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <20061227212555.GA14947@elte.hu>
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	 <20061227212555.GA14947@elte.hu>
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Date: Wed, 27 Dec 2006 13:54:15 -0800
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On Wed, 2006-12-27 at 22:25 +0100, Ingo Molnar wrote:
> 
> +void pagefault_disable(void)
> +{
> +       current->pagefault_disabled++;
> +       /*
> +        * make sure to have issued the store before a pagefault
> +        * can hit.
> +        */
> +       barrier();
> +}
> +
> +void pagefault_enable(void)
> +{
> +       /*
> +        * make sure to issue those last loads/stores before enabling
> +        * the pagefault handler again.
> +        */
> +       barrier();
> +       current->pagefault_disabled--;
> +}
> +

I'll test it, but clearly I'm not going to get the same scheduling while
atomic using this change.. So may as well just put it in -rt and see if
something crashes ..

Daniel