Hello All, Will appreciate if someone can clear my doubts regarding XOR/GF offload infrastructure for raid5/6. I digged through code and linux/Documentation but not thoroughly clear about few things. 1) What is the purpose of device_prep_dma_interrupt callback? 2) My driver currently polls for checking the xor completions and does'nt implement device_prep_dma_interrupt callback at all. What performance variation I can expect by implementing this callback in my async_tx driver. 3) Purpose of DMA_ACK as I read - it is for higher layers to inform dma driver that descriptors can now be freed. Can someone explain this with an example as applicable with raid5/6 clients. 4) With example - why dma_run_dependencies(tx) needed after the hardware engine posts completion for a descriptor. 5) Purpose of tx->callback(cb_arg) - again with an example from a raid5/6 offload perspective. I want to use offload engine efficiently with recent multithreaded raid5/6. Thanks & Regards Vikas Aggarwal -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
