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From: Richard Henderson <rth@twiddle.net>
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Date: Tue, 18 Jul 2017 13:43:13 -1000
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Subject: Re: [Qemu-devel] [PATCH v2 10/45] translate-all: guarantee that
 tb_hash only holds valid TBs
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To: "Emilio G. Cota" <cota@braap.org>
Cc: qemu-devel@nongnu.org

On 07/18/2017 01:30 PM, Emilio G. Cota wrote:
> Should I do those updates in the same patch where tb->invalid is brought
> over to cflags? Alternatives: have a later patch where all readers
> are converted to atomic_read, or keep tb->invalid as a separate field (we
> could use that 4-byte hole in struct tb_tc..)

I would prefer the readers be converted in a separate patch.
I wonder if an accessor inline might be in order?

static inline uint32_t tb_cflags(TranslationBlock *tb)
{
     return atomic_read(tb->cflags);
}

That might keep line lengths from expanding too much...

Please don't try to do anything clever to re-use padding holes.
I think that's just confusing and probably premature optimization.


r~