Re: [PATCH 2/4] arch: Add lightweight memory barriers fast_rmb() and fast_wmb()

Benjamin Herrenschmidt
2014-11-18T00:43:32Z

On Mon, 2014-11-17 at 13:54 -0800, Alexander Duyck wrote:

> What would you think of the name "coherent_*mb()"? I would prefer to
> avoid dma in the name since, at least in my mind, that implies MMIO.

I'm lazy, I like typing less, so I like dma_* but I don't object to
coherent_* if at least one more person thinks it makes the semantics
clearer :)

> It also ties in well with dma_alloc_coherent/dma_free_coherent which is
> what would typically be used to allocate the memory we would be using
> the barrier to protect anyway.

Agreed.

> > And yes, in the same spirit, it would probably be good to try to
> > eventually get rid of the plain "*mb()" functions, and perhaps call
> > them "mmio_*mb()" to clarify that they are about ordering memory wrt
> > mmio.
> >
> > Hmm?
> >
> > Linus
>
> I will work on pulling all of the coherent barrier cases out of using
> the plain "*mb()" calls first. We need to sort that out before we could
> look at renaming the plain barrier functions.

Makes sense.

Cheers,
Ben.

> - Alex
> --
> 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/