On 31/05/19 05:27, Ming Lei wrote: > It should be fine to implement scsi_commit_rqs() as: > > if (shost->hostt->commit_rqs) > shost->hostt->commit_rqs(shost, hctx->queue_num); > > then scsi_mq_ops_no_commit can be saved. > > Because .commit_rqs() is only called when BLK_STS_*_RESOURCE is > returned from scsi_queue_rq(), at that time shost->hostt->commit_rqs should > have been hit from cache given .queuecommand is called via > host->hostt->queuecommand. This is not about d-cache, it's about preserving the heuristics that blk-mq applies depending on whether commit_rqs is there or not. Paolo