Re: [PATCH] net/macb: Use dmapool to align descriptors on 64bits

From: Ben Hutchings
Date: Mon Dec 03 2012 - 09:01:25 EST


On Mon, 2012-12-03 at 13:15 +0100, Nicolas Ferre wrote:
> Depending on datapath, some revisions of GEM need
> 64bits aligned descriptors. Use dmapool to allocate
> these descriptors.
> Note that different size between RX and TX rings
> leads to the creation of two pools.
>
> Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
[...]

dma_alloc_coherent() allocates whole pages, which I think is quite
enough alignment. You can't save memory by doing this, since each pool
needs at least one page. So what is this change meant to achieve?

Ben.

--
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

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