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Date: Tue, 8 Oct 2013 11:56:02 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>, Andrew Morton <akpm@linux-foundation.org>,
        Alex Thorlton <athorlton@sgi.com>, Ingo Molnar <mingo@redhat.com>,
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        Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCHv5 00/11] split page table lock for PMD tables
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On Tue, Oct 08, 2013 at 12:50:06PM +0300, Kirill A. Shutemov wrote:
> I want to rework code around page->ptl a bit more:
>  - allow pgtable_page_ctor() to fail and modify callers to handle it;
>  - if sizeof(spinlock_t) > sizeof(long) allocate the spinlock_t
>    dynamically.
> 
> It will allow to use split lock with DEBUG_SPINLOCK and DEBUG_LOCK_ALLOC.
> And it will make -rt guys happier. ;)

Oh yes, if you've got the time to do that, that would be great. It would
reduce the -rt patch by one ugly hack.