On Sun, Oct 14, 2012 at 09:54:24AM -0600, Shuah Khan wrote: > diff --git a/Documentation/DMA-API-HOWTO.txt b/Documentation/DMA-API-HOWTO.txt > index a0b6250..cf1adb4 100644 > --- a/Documentation/DMA-API-HOWTO.txt > +++ b/Documentation/DMA-API-HOWTO.txt > @@ -468,11 +468,46 @@ To map a single region, you do: > size_t size = buffer->len; > > dma_handle = dma_map_single(dev, addr, size, direction); > + if (unlikely(dma_mapping_error(dma_handle))) { Don't encourage people to put unlikely() and likely() into their driver code. It should only be used after benchmarking both with and without. I can't imagine how it would make a measurable difference here. regards, dan carpenter _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel