Messages in this thread | | | Subject | Re: [PATCH v5 2/4] arch: Add lightweight memory barriers dma_rmb() and dma_wmb() | From | Benjamin Herrenschmidt <> | Date | Wed, 26 Nov 2014 10:15:28 +1100 |
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On Tue, 2014-11-18 at 17:24 -0800, Alexander Duyck wrote: > There are a number of situations where the mandatory barriers rmb() and > wmb() are used to order memory/memory operations in the device drivers > and those barriers are much heavier than they actually need to be. For > example in the case of PowerPC wmb() calls the heavy-weight sync > instruction when for coherent memory operations all that is really needed > is an lsync or eieio instruction. > .../...
For powerpc:
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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