Hi Jens The 1st patch refactors the code of issue request directly. It merges the blk_mq_try_issue_directly and __blk_mq_try_issue_directly and make it handle the return value of .queue_rq itself. The 2nd patch let the requests be inserted into hctx->dispatch when the queue is stopped or quiesced if bypass_insert is true. The 3rd patch make blk_mq_sched_insert_requests issue requests directly with 'bypass_insert' false, then it needn't to handle the non-issued requests any more. The 4th patch ensures the hctx to be ran on its mapped cpu in issue directly path. V3: - Correct the code about the case bypass_insert is true and io scheduler attached. The request still need to be issued in case above. (1/4) - Refactor the code to make code clearer. (1/4) - Add the 2nd patch. - Modify the code to adapt the new patch 1. V2: - Add 1st and 2nd patch Jianchao Wang(4) blk-mq: refactor the code of issue request directly blk-mq: insert request without involving any io blk-mq: issue directly with bypass_insert 'false' in blk-mq: ensure hctx to be ran on mapped cpu when issue block/blk-mq-sched.c | 8 ++- block/blk-mq.c | 139 ++++++++++++++++++++++++++++++--------------------- block/blk-mq.c.rej | 60 ++++++++++++++++++++++ 3 files changed, 146 insertions(+), 61 deletions(-)