From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Subject: Re: [PATCH 2/3] KVM: MMU: move bits lost judgement into a separate
 function
Date: Mon, 02 Aug 2010 15:50:57 +0800
Message-ID: <4C5678E1.2040107@cn.fujitsu.com>
References: <4C4E5313.1080308@cn.fujitsu.com> <4C4E536E.7030109@cn.fujitsu.com> <4C567694.2090808@redhat.com>
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>,
	KVM list <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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Avi Kivity wrote:
>  On 07/27/2010 06:33 AM, Xiao Guangrong wrote:
>> Introduce spte_bits_lost() function to judge whether spte bits will
>> miss, it's more readable and can help us to cleanup code later
>>
>> Signed-off-by: Xiao Guangrong<xiaoguangrong@cn.fujitsu.com>
>> ---
>>   arch/x86/kvm/mmu.c |   20 +++++++++++++++++---
>>   1 files changed, 17 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
>> index e10f2bd..dd6c192 100644
>> --- a/arch/x86/kvm/mmu.c
>> +++ b/arch/x86/kvm/mmu.c
>> @@ -303,6 +303,20 @@ static u64 __xchg_spte(u64 *sptep, u64 new_spte)
>>   #endif
>>   }
>>
>> +static bool spte_bits_lost(u64 spte)
>> +{
>> +    if (!shadow_accessed_mask)
>> +        return false;
>> +
>> +    if (!is_shadow_present_pte(spte))
>> +        return false;
>> +
>> +    if (spte&  shadow_accessed_mask)
>> +        return false;
>> +
>> +    return true;
>> +}
> 
> IMO spte_has_volatile_bits() is a clearer name, "lost" implies they are
> already gone.

Yeah, it's the better name, will fix soon.