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Subject: Re: [PATCH 0/2] Use named address spaces for percpu data
To:     Matthew Wilcox <willy@infradead.org>,
        Ingo Molnar <mingo@kernel.org>
Cc:     Waiman Long <longman@redhat.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org
References: <20180912144442.29271-1-willy@infradead.org>
From:   Richard Henderson <rth@twiddle.net>
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Message-ID: <988cf77c-e0cc-25fb-dcd6-945e6f2ba65e@twiddle.net>
Date:   Wed, 12 Sep 2018 08:08:01 -0700
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On 09/12/2018 07:44 AM, Matthew Wilcox wrote:
> rth wrote a patch back in 2016 that uses gcc's address space machinery
> to improve code generation for percpu accesses.  Ingo asked for some
> minor changes to be made, but Richard didn't respond.  While looking at
> something related, I came across them, and asked Richard's permission
> to resurrect and resend the patch, with the changes Ingo asked for at
> the time.
> 
> The important information about why we want these patch is in 1/2.
> 
> Richard Henderson (2):
>   x86: Use named address spaces in asm/percpu.h
>   x86: Enable named address spaces for percpu data
> 
>  arch/x86/include/asm/percpu.h | 147 ++++++++++++++++++++--------------
>  1 file changed, 88 insertions(+), 59 deletions(-)

Thanks for resurrecting this, Willy.  I'd totally forgotten about it.
The adjustments you made look fine.


r~