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Message-ID: <1371704216.3944.4.camel@pasglop>
Subject: Re: [PATCH -V2] powerpc/kvm: Handle transparent hugepage in KVM
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Thu, 20 Jun 2013 14:56:56 +1000
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References: <1371703304-31687-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
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On Thu, 2013-06-20 at 10:11 +0530, Aneesh Kumar K.V wrote:
> +       while (1) {
> +               old_pte = pte_val(*ptep);
> +               /*
> +                * wait until _PAGE_BUSY is clear then set it
> atomically
> +                */
> +               if (unlikely(old_pte & _PAGE_BUSY))
> +                       continue;
> +

Add a cpu_relax...

Cheers,
Ben.