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Message-ID: <1336642715.2527.84.camel@twins>
Subject: Re: [PATCH v4 5/7] x86/tlb: add tlb flush all factor for specific
 CPU
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Alex Shi <alex.shi@intel.com>
Cc: rob@landley.net, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
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Date: Thu, 10 May 2012 11:38:35 +0200
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On Thu, 2012-05-10 at 13:00 +0800, Alex Shi wrote:


> +void intel_tlb_flushall_factor_set(struct cpuinfo_x86 *c)
> +{
> +       if (!cpu_has_invlpg) {
> +               tlb_flushall_factor = -1;
> +               return;
> +       }

...

> +       if (!cpu_has_invlpg || vma->vm_flags & VM_HUGETLB
> +                       || tlb_flushall_factor == (u16)TLB_FLUSH_ALL)
> {
>  flush_all: 

Since you set tlb_flushall_factor (I'd have called it _shift) to -1
when !invlpg there's a redundant check in there.