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Date: Mon, 10 Nov 2014 13:47:01 -0800
Message-ID: <CA+55aFyh1ZOuLZw5Vb_ZTYhSsbwdqRFOceYSj7nh02NmKxy4AQ@mail.gmail.com>
Subject: Re: [PATCH 3/5] lib: lockless generic and arch independent page table
 (gpt) v2.
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Jerome Glisse <j.glisse@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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On Mon, Nov 10, 2014 at 1:35 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> Or do you actually have a setup where actual non-CPU hardware actually
> walks the page tables you create and call "page tables"?

So just to clarify: I haven't looked at all your follow-up patches at
all, although I've seen the overviews in earlier versions. When trying
to read through the latest version, I got stuck on this one, and felt
it was crazy.

But maybe I'm misreading it and it actually has good reasons for it.
But just from the details I look at, some of it looks too incestuous
with the system (the split PTL lock use), other parts look really
really odd (like the 64-bit shift counts), and some of it looks just
plain buggy (the bitops for synchronization). And none of it is all
that easy to actually read.

                        Linus
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