Message-ID: <4FA9CB38.3080606@intel.com>
Date: Wed, 09 May 2012 09:41:12 +0800
From: Alex Shi <alex.shi@intel.com>
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To: "H. Peter Anvin" <hpa@zytor.com>
CC: mgorman@suse.de, npiggin@gmail.com, tglx@linutronix.de, mingo@redhat.com,
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Subject: Re: [PATCH v3 4/7] x86/tlb: add tlb flush all factor for specific
 CPUs
References: <1336485790-30902-1-git-send-email-alex.shi@intel.com> <1336485790-30902-5-git-send-email-alex.shi@intel.com> <4FA93946.2000302@zytor.com>
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On 05/08/2012 11:18 PM, H. Peter Anvin wrote:

> On 05/08/2012 07:03 AM, Alex Shi wrote:
>>  
>> -	if (!cpu_has_invlpg || vma->vm_flags & VM_HUGETLB) {
>> +	if (!cpu_has_invlpg || vma->vm_flags & VM_HUGETLB
>> +				|| !tlb_flushall_factor) {
> 
> OK nevermind on the division by zero, but this yet another test being
> performed.
> 
> If nothing else you could fold these tests and make tlb_flushall_factor
> zero if !cpu_has_invlpg.


Yes, should be.

> 
> 	-hpa
> 


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