Re: [PATCH 0/2] Fix misuse of blk_rq_stats in blk-iolatency

[Pavel Begunkov]

Hi,

Josef, thanks for taking a look.


Although, there is nothing critical yet -- just a not working / disabled
optimisation, but changes in stats could sublty break it. E.g. grouping
@batch and @mean into a union will increase estimated average by several
orders of magnitude.

Jens, what do you think?



On 14/06/2019 16:40, Josef Bacik wrote:
> On Fri, Jun 14, 2019 at 02:44:11PM +0300, Pavel Begunkov (Silence) wrote:
>> From: Pavel Begunkov <asml.silence@xxxxxxxxx>
>>
>> There are implicit assumptions about struct blk_rq_stats, which make
>> it's very easy to misuse. The first patch fixes consequences, and the
>> second employs type-system to prevent recurrences.
>>
>>
>> Pavel Begunkov (2):
>>   blk-iolatency: Fix zero mean in previous stats
>>   blk-stats: Introduce explicit stat staging buffers
>>
> 
> I don't have a problem with this, but it's up to Jens I suppose
> 
> Acked-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
> 
> Thanks,
> 
> Josef
> 

-- 
Yours sincerely,
Pavel Begunkov

Attachment: signature.asc
Description: OpenPGP digital signature