Messages in this thread | | | Date | Mon, 2 Jun 2014 09:46:55 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH v2] introduce atomic_pointer to fix a race condition in cancelable mcs spinlocks |
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On Mon, Jun 02, 2014 at 06:30:32PM +0200, Peter Zijlstra wrote: > On Mon, Jun 02, 2014 at 06:25:25PM +0200, Peter Zijlstra wrote: > > I'm almost inclined to just exclude parisc from using opt spinning. > > > > That said, this patch still doesn't address the far more interesting > > problem of actually finding these issues for these few weird archs. > > So why do these archs provide xchg() and cmpxchg() at all? Wouldn't it > be much simpler if archs that cannot sanely do this, not provide these > primitives at all?
Such architectures would also need to avoid NO_HZ_FULL_SYSIDLE and RCU_NOCB_CPU, but those are probably entirely reasonable restrictions.
Thanx, Paul
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