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Date: Tue, 5 Dec 2017 15:08:50 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Dave Hansen <dave.hansen@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Will Deacon <will.deacon@arm.com>,
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        Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: [patch 55/60] x86/mm: Use INVPCID for __native_flush_tlb_single()
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On Tue, Dec 05, 2017 at 05:51:28AM -0800, Dave Hansen wrote:
> On 12/04/2017 02:51 PM, Peter Zijlstra wrote:
> > We should find some of the benchmarks that were used to determine
> > tlb_single_page_flush_ceiling and measure. I've not gotten around to
> > doing either.
> > 
> > Someone called Dave Hansen did that patch and might still have something
> > lying around to help with that:
> > 
> >   a5102476a24b ("x86/mm: Set TLB flush tunable to sane value (33)")
> 
> I hate git. :)

:-)

> But, yeah, we have certainly changed enough variables to necessitate
> measuring it again.

Its more than that, I think much of that could show if it makes sense to
use invpcid_flush_one() at all.