Messages in this thread |  | | Date | Mon, 7 Jan 2013 18:15:00 -0200 | From | Mauro Carvalho Chehab <> | Subject | Re: [PATCH v3 2/4] videobuf2-dma-streaming: new videobuf2 memory allocator |
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Em Mon, 7 Jan 2013 12:40:50 -0700 Jonathan Corbet <corbet@lwn.net> escreveu:
> On Mon, 7 Jan 2013 00:09:47 +0100 > Alessandro Rubini <rubini@gnudd.com> wrote: > > > I don't expect you'll see serious performance differences on the PC. I > > think ARM users will have better benefits, due to the different cache > > architecture. You told me Jon measured meaningful figures on a Marvel > > CPU. > > It made the difference between 10 frames per second with the CPU running > flat out and 30fps mostly idle. I think that probably counts as > meaningful, yeah...:)
Couldn't this performance difference be due to the usage of GFP_DMA inside the VB2 code, like Federico's new patch series is proposing?
If not, why are there a so large performance penalty?
Regards, Mauro
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