Re: [PATCH BUGFIX 0/2] bfq: fix unbalanced decrements causing loss of throughput

From: Paolo Valente
Date: Mon Jan 14 2019 - 04:10:05 EST




> Il giorno 7 dic 2018, alle ore 15:40, Jens Axboe <axboe@xxxxxxxxx> ha scritto:
>
> On 12/7/18 3:01 AM, Paolo Valente wrote:
>>
>>
>>> Il giorno 7 dic 2018, alle ore 03:23, Jens Axboe <axboe@xxxxxxxxx> ha scritto:
>>>
>>> On 12/6/18 11:18 AM, Paolo Valente wrote:
>>>> Hi Jens,
>>>> the first patch in this series fixes an error in the decrementing of
>>>> the counter of the number of groups with pending I/O. This wrong
>>>> decrement caused loss of throughput or, less likely, of control on
>>>> I/O. The second patch is a fix of some wrong comments, which somehow
>>>> contributed to making the above bug more difficult to find.
>>>
>>> Are you fine with this going into 4.21? I can't quite tell what your
>>> intent is. The first patch has a Fixes for something
>>
>> yep, that fixes a serious error.
>>
>>> that went into
>>> this series, but then patch 2 is a comment update that would not
>>> normally be something to be applied at this stage.
>>>
>>
>> and yes, only comments changed by the second one
>>
>> May it make sense to apply them in two steps, one in the 4.20 and the other one in the 4.21?
>
> I think so, I'll do that.

Hi Jens,
is the second patch still queued?

Thanks,
Paolo

>
> --
> Jens Axboe