Messages in this thread | | | Date | Mon, 27 Aug 2007 16:19:41 -0400 | From | Mathieu Desnoyers <> | Subject | Re: [patch 00/28] Add cmpxchg64_local and cmpxchg_local to each architecture |
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* Christoph Lameter (clameter@sgi.com) wrote: > On Mon, 27 Aug 2007, Mathieu Desnoyers wrote: > > > Here is the patch series for 2.6.23-rc3-mm1 that adds cmpxchg_local, and now > > also cmpxchg64_local, to each architecture. > > Any planned uses of cmpxchg64_local?
Let's say it could possibly eliminate the xtime read seqlock on x86 (should be investigated) and can be useful to overcome the non-synchronized TSC handling when taking TSC-based timestamps. All these operations require locking to play with 64 bits values on 32 bits architectures, which could be improved by cmpxchg64_local.
But again, it would require some testing to see if we can improve performances there.
Mathieu
-- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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