[PATCH] Handle abortTransaction with RTM

Torvald Riegel triegel@redhat.com
Mon Nov 12 10:47:00 GMT 2012


On Fri, 2012-11-09 at 21:54 +0100, Andi Kleen wrote:
> > I'm not sure this is quite true.  If a libitm-executed transaction is
> 
> It's just a convention. You don't have to use it.

That's true ...

> Not doing it will
> just make abort profiling harder.

... but I disagree with this one.  This won't only make profiling
harder, but it also can have a negative impact on performance.  If you
think that there's something wrong with the reasons that I gave for why
this can be a performance issue, please say why you think so instead of
just saying that it's just about profiling.

To avoid the potential performance complications, it would probably be
sufficient to encourage people to follow this convention.  For example,
making sure that libitm and other libraries such as glibc are aware of
it (or, ideally, follow it) would cover most of the combinations I
suppose;  perhaps the convention should also be mentioned in the RTM
intrinsics header file.


Torvald



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