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Subject: Re: [PATCH] arm64: add PAGE_ALIGNED_DATA to linker script
From: Mark Salter <msalter@redhat.com>
To: Will Deacon <will.deacon@arm.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Catalin Marinas <Catalin.Marinas@arm.com>
Date: Fri, 11 Oct 2013 08:18:41 -0400
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On Wed, 2013-10-09 at 11:14 +0100, Will Deacon wrote:
> > @@ -110,6 +110,7 @@ SECTIONS
> >                */
> >               INIT_TASK_DATA(THREAD_SIZE)
> >               NOSAVE_DATA
> > +             PAGE_ALIGNED_DATA(PAGE_SIZE)
> >               CACHELINE_ALIGNED_DATA(64)
> >               READ_MOSTLY_DATA(64)
> 
> Can we just replace this chunk with RW_DATA_SECTION(64, PAGE_SIZE,
> THREAD_SIZE) instead?
> 

I took a look at this. It can be done, but the RW_DATA_SECTION aligns
data to PAGE_SIZE where the existing alignment is THREAD_SIZE. So using
RW_DATA_SECTION would waste some space if using 64K pagesize.

--Mark