On 21 April 2011 08:29, Shawn Guo <shawn.guo@xxxxxxxxxxxxx> wrote: > On Wed, Apr 20, 2011 at 05:30:22PM +0200, Per Forlin wrote: > [...] >> Remove dma_map and dma_unmap from your host driver and run the tests >> (obviously nonblocking and blocking will have the same results). If >> there is still no performance gain the cache penalty is very small on >> your platform and therefore nonblocking doesn't improve things much. >> Please let me know the result. >> > Sorry, I could not understand. What's the point to run the test when > the driver is even broken. The removal of dma_map_sg and > dma_unmap_sg makes mxs-mmc host driver broken. The point is only to get a measurement of the cost of handling dma_map_sg and dma_unmap_sg, this is the maximum time mmc nonblocking can save. The nonblocking mmc_test should save the total time of dma_map_sg and dma_unmap_sg, if the pre_req and post_req hooks are implemented correctly. Running without dma_map_sg and dma_unmap_sg will confirm if the pre_req and post_req hooks are implemented correctly. > > -- > Regards, > Shawn > > Regards, Per -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
