On Thu, Jun 20, 2013 at 02:20:30PM -0700, Dan Williams wrote: > On Wed, Jun 19, 2013 at 9:28 AM, Jon Mason <jon.ma...@intel.com> wrote: > > On Tue, Jun 18, 2013 at 06:13:28PM -0700, Dan Williams wrote: > [..] > > NTB is currently using it to flush any pending DMAs. This is needed > > to allow the DMA engine and the CPU to perform operations on the same > > "Memory Window". Without this, it is possible for the operations to > > complete out of order, which is not a desired outcome for any network > > traffic over NTB. CPU is preferred over DMA engine for small > > transfers. Also, it provides an alternative for errors in the DMA > > engine copy process (e.g., DMA mapping, device_prep_dma_memcpy, and > > dmaengine_submit). > > Ok there really isn't a better alternative, is NTB always polling or > does it also use completion callbacks?
It uses the callbacks. I've change the code to use dma_find_channel, and will push it for review as a RFC shortly. Thanks, Jon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
