Re: [PATCH 1/3] Rename TIF_PERFMON_WORK back to TIF_NOTIFY_RESUME

From: stephane eranian <eranian_at_googlemail.com>
Date: 2007-12-13 03:18:20
Petr,


On Dec 12, 2007 12:07 PM, Petr Tesarik <ptesarik@suse.cz> wrote:
>
> I'm making a mental note to review this later for optimization. AFAICS
> fetching the pfm_needs_checking field is not too costly, but of course
> it's an extra memory reference (and possibly a cache miss).
>
Yes. The TIF flag has the advantage of being in the same cacheline.

> On a related note, I think that we should be able to use all 8 bits for
> pending work TIF_ bits despite the brain-damaged sign extension in "and
> imm8", but I don't have the time now to go through all uses of the
> thread flags in assembly. Not really sure if it's worth adding one TIF_
> bit, because we'll pretty certainly need one more bit in the future...
>
Yes, I ran into that difficulty myself when I tried adding my TIF flag.
Not sure how you could work around it.

> Anyway, I'd like to push the changes to ptrace first, because that's
> currently broken.
That's fine. What you have right now show work.

thanks.
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Received on Thu Dec 13 03:19:10 2007

This archive was generated by hypermail 2.1.8 : 2007-12-13 03:19:29 EST