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Date:   Thu, 16 Aug 2012 21:42:10 +0200
From:   Andrea Arcangeli <aarcange@redhat.com>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        linux-mm@kvack.org, Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [PATCH v3 6/7] mm: make clear_huge_page cache clear only around
 the fault address
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On Thu, Aug 16, 2012 at 09:37:25PM +0300, Kirill A. Shutemov wrote:
> On Thu, Aug 16, 2012 at 08:29:44PM +0200, Andrea Arcangeli wrote:
> > On Thu, Aug 16, 2012 at 07:43:56PM +0300, Kirill A. Shutemov wrote:
> > > Hm.. I think with static_key we can avoid cache overhead here. I'll try.
> > 
> > Could you elaborate on the static_key? Is it some sort of self
> > modifying code?
> 
> Runtime code patching. See Documentation/static-keys.txt. We can patch it
> on sysctl.

I guessed it had to be patching the code, thanks for the
pointer. It looks a perfect fit for this one agreed.