Messages in this thread | | | Date | Fri, 12 Jun 2015 10:42:51 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH v2 3/4] x86, mwaitt: introduce mwaix delay with a configurable timer |
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On Tue, Jun 09, 2015 at 09:46:52AM -0700, Andy Lutomirski wrote: > I don't like this hack. The compiler is entirely within is rights to > poke addr's cacheline (i.e. the stack) between the two instructions. > I'd suggest either making the thing a full cacheline long or using a > single asm statement.
How about this:
/* * This should be a memory location in a cache line which is * unlikely to be touched by other processors. The actual * content is immaterial as it is not actually modified in any way. */ mwait_ptr = ¤t_thread_info()->flags;
and then
__monitor(mwait_ptr, 0, 0);
We already do this in mwait_play_dead().
However, am I even correct in assuming that ->flags won't really be touched as we're doing delay() and nothing pokes into current anyway?
Thanks.
-- Regards/Gruss, Boris.
ECO tip #101: Trim your mails when you reply. --
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