2011/8/11 Shaohua Li <shli@xxxxxxxxxx>: > 2011/8/11 Kyungmin Park <kmpark@xxxxxxxxxxxxx>: >> Hi Jens >> >> Now eMMC device requires the upper layer information to improve the data >> performance and reliability. >> >> . Context ID >> Using the context information, it can sort out the data internally and improve the performance. >> The main problem is that it's needed to define "What's the context". >> Actually I expect cfq queue has own unique ID but it doesn't so decide to use the pid instead >> >> . Data Tag >> Using the Data Tag (1-bit information), It writes the data at SLC area when it's hot data. So it can make the chip more reliable. >> First I expect the REQ_META but current ext4 doesn't pass the WRITE_META. only use the READ_META. so it needs to investigate it. >> >> With these characteristics, it's helpful to teach the device. After some consideration. it's needed to pass out these information at request data structure. >> >> Sample usage is following in drivers/mmc/card/block.c >> >> struct elevator_queue *e = md->queue.queue->elevator; >> struct request_hint hint; >> int ret; >> >> if (e->ops->elevator_get_req_hint_fn && req) >> ret = e->ops->elevator_get_req_hint_fn(req, &hint); > please put this to blkdev.h or similar. directly using it here > is abnormal. BTW, we can add a (rq->cmd_flags & REQ_ELVPRIV) check here to make sure the request is at io scheduler. -- 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
