[openib-general] Re: [PATCH (updated)] ipoib: dont lock tx on completion

[Roland Dreier]

    Michael> Can they be moved to before the wmb? I think not.

Why not?  All wmb() does is guarantee that stores issued before the
wmb() will complete before stores issued after the wmb().  It doesn't
even say anything about when the stores have to complete, let alone
the order of loads.  The most obvious definition is for sparc64, where
we have

	#define wmb()           membar("#StoreStore")

which my Sparc reference manual says only means

    Forces all stores after the MEMBAR to wait until all stores before
    the MEMBAR have reached global visibility.

ppc is similar, where wmb() is just "eieio."

 - R.