> On Fri, Sep 01, 2017 at 01:24:16PM +0000, Reshetova, Elena wrote: > > > > > On Fri, Sep 01, 2017 at 11:05:33AM +0000, Reshetova, Elena wrote: > > > > Actually on the second thought: does the above memory ordering differences > > > > really apply when we have ARCH_HAS_REFCOUNT? To me it looks like the way > > > > how it is currently implemented for x86 is the same way as it is for atomic > cases. > > > > > > Never look to x86 for memory ordering, its boring. > > > > > > And yes, for the ARM implementation it can certainly make a difference. > > > > So, yes, what I am trying to say is that it can really depend if you have > ARCH_HAS_REFCOUNT > > enabled or not and then also based on architecture. Thus I believe is also true for > atomic: there > > might be differences when you use arch. dependent version of function or not. > > So the generic one in lib/refcount.c is already weaker on ARM, they > don't need to do a ARCH specific 'fast' implementation for the > difference to show up. But can they make "fast" implementation on ARM that would give stronger memory guarantees?
