Re: [PATCH V4 0/5] blk-mq: refactor and fix on issue request directly

["jianchao.wang" <jianchao.w.wang@oracle.com>]

Would anyone please take a look at this ?

Thanks
Jianchao

On 11/2/18 3:08 PM, Jianchao Wang wrote:
> Hi Jens
> 
> These patch set refactors the code of issueing request driectly and
> fix some defects.
> 
> The 1st patch make __blk_mq_issue_directly be able to accept NULL cookie
> pointer.
> 
> The 2nd 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 3rd patch let the requests be inserted into hctx->dispatch when
> the queue is stopped or quiesced if bypass is true.
> 
> The 4th patch make blk_mq_sched_insert_requests issue requests directly
> with 'bypass' false, then it needn't to handle the non-issued requests
> any more.
> 
> The 5th patch ensures the hctx to be ran on its mapped cpu in issue directly
> path.
> 
> V4:
>  - split the original patch 1 into two patches, 1st and 2nd patch currently
>  - rename the mq_decision to mq_issue_decision
>  - comment changes
> 
> 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. blk_mq_make_request is introduced
>    to decide insert, end or just return based on the return value of .queue_rq
>    and bypass_insert (1/4) 
>  - Add the 2nd patch. It introduce a new decision result which indicates to
>    insert request with blk_mq_request_bypass_insert.
>  - Modify the code to adapt the new patch 1.
> 
> V2:
>  - Add 1st and 2nd patch
> 
> Jianchao Wang (5)
> blk-mq: make __blk_mq_issue_directly be able to accept
> blk-mq: refactor the code of issue request directly
> blk-mq: fix issue directly case when q is stopped or
> blk-mq: issue directly with bypass 'false' in
> blk-mq: ensure hctx to be ran on mapped cpu when issue
> 
>  block/blk-mq-sched.c |   8 ++-
>  block/blk-mq.c       | 149 ++++++++++++++++++++++++++++++---------------------
>  2 files changed, 92 insertions(+), 65 deletions(-)
> 
> Thanks
> Jianchao
>