Re: [patch]blk-mq: blk_mq_tag_to_rq should handle flush request

Jens Axboe
2014-06-04T15:20:01Z

On 2014-06-04 09:16, Christoph Hellwig wrote:
> On Wed, Jun 04, 2014 at 09:11:47AM -0600, Jens Axboe wrote:
>> On 2014-06-04 09:10, Christoph Hellwig wrote:
>>> On Wed, Jun 04, 2014 at 09:08:12AM -0600, Jens Axboe wrote:
>>>>> The performance regression is caused by "blk-mq: avoid code
>>>>> duplication", but I don't really understand why yet.
>>>>
>>>> Gah, looks like this one dropped the tag idling. I bet that is why.
>>>
>>> Ah, thanks. It's indeed exactly the same sort of slow down I bisected
>>> back then, this should have rung a bell instead of keeping me occupied
>>> for hours..
>>
>> Patch is committed :-)
>
> Oh well, I had just prepared the same one for you, but I want to at
> least do basic sanity checking of my rebased tree with the fixes applied
> now that I'm done bisecting.

Please do. If there's anything else I need, let me know. It wasn't clear
to me if the cdb patch was in blk-mq or scsi-mq. I'll flush my queue out
this afternoon, so that -rc1 will hopefully have everything in a sane state.

--
Jens Axboe