On Fri, Jul 3, 2015 at 11:03 AM, Russell King - ARM Linux <[email protected]> wrote: > On Wed, Jul 01, 2015 at 12:12:51PM +0100, Catalin Marinas wrote: >> On Tue, Jun 30, 2015 at 11:29:06PM +0200, Lorenzo Nava wrote: >> > This patch allows the use of CMA for DMA coherent memory allocation. >> > At the moment if the input parameter "is_coherent" is set to true >> > the allocation is not made using the CMA, which I think is not the >> > desired behaviour. >> > >> > Signed-off-by: Lorenzo Nava <[email protected]> >> > Reviewed-by: Catalin Marinas <[email protected]> >> >> If Russell doesn't have any objections, you can send the patch to >> his patch system. See here for more information: > > I'm left wondering whether this patch is really want Lorenzo wants. > From my reading of it, while this has the effect of allocating from > CMA for coherent devices, it's no different from the non-coherent > case, because by calling __alloc_from_contiguous(), we end up > remapping the allocated memory, removing the cacheability status > from the allocated pages. > > This brings up an interesting point: presumably, it's been tested, and > people are happy with the performance it's giving, inspite of it not > returning cacheable memory... or maybe it hasn't been tested that much? >
As Catalin correctly pointed out, I always consider that this patch: > -- > FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up > according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
