Message-ID: <4FA93946.2000302@zytor.com>
Date: Tue, 08 May 2012 08:18:30 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Alex Shi <alex.shi@intel.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>
In-Reply-To: <1336485790-30902-5-git-send-email-alex.shi@intel.com>
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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.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

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