Re: [RFC PATCH] ARM: mm: disable kmap_high_get() for SMP

[Nicolas Pitre]

On Mon, 4 Mar 2013, Joonsoo Kim wrote:

> With SMP and enabling kmap_high_get(), it makes users of kmap_atomic()
> sequential ordered, because kmap_high_get() use global kmap_lock().
> It is not welcome situation, so turn off this optimization for SMP.

I'm not sure I understand the problem.

The lock taken by kmap_high_get() is released right away before that 
function returns and therefore this is not actually serializing 
anything.


Nicolas
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