Messages in this thread | | | Date | Wed, 26 Nov 2014 16:04:56 +0000 | From | Will Deacon <> | Subject | Re: [PATCH v5 2/4] arch: Add lightweight memory barriers dma_rmb() and dma_wmb() |
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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
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