Re: [PATCH v5 2/4] arch: Add lightweight memory barriers dma_rmb() and dma_wmb()

[Will Deacon]

On Tue, Nov 25, 2014 at 04:26:28PM +0000, Alexander Duyck wrote:
> On 11/25/2014 06:01 AM, Will Deacon wrote:
> > If we ever see platforms using Linux/dma_alloc_coherent with devices
> > mastering from a different outer-shareable domain that the one containing
> > the CPUs, then we'll need to revisit this.
> 
> Would we just need a system wide memory barrier in that case instead of 
> an outer shareable memory barrier, or would we need to look as something 
> like a sync barrier?

I think dmb(sy) would do the trick, but let's cross that bridge if/when we
have to.

Will
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/