Re:Re: Re: cgroup: Fix split bio been throttled more than once

[aaronlee0817 <aaronlee0817@163.com>]

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>At 2016-07-06 23:06:29, "Tejun Heo" <tj@kernel.org> wrote:
>Hello,
>
>On Wed, Jul 06, 2016 at 10:58:55PM +0800, aaronlee0817 wrote:
>> >But that said, can't we just copy BIO_THROTLED while splitting?
>> 
>> In my opinion， copying BIO_THROTLED while splitting doesn't work
>> with this, because, the bio within the limit will not set BIO_THROTLED
>> but will be split, and back to call generic_make_request(), and will be 
>> count twice.
>
>I see.  It's just a bit weird that we're marking this from clone site
>when it's an issue which is specific to throttling.  The thing is
>depending on how bio clone is used, it could misbehave in the other
>direction (bio not accounted at all).  What we want to know is whether
>a bio has been previously accounted or not, rather than whether a bio
>is a result of splitting.  I think it'd be better to track that

>instead.


Yea, I agree with you, we should consider this more carefully, I will
check more about what you mentioned and to see if we have better
way to fix this.


>
>Thanks.
>
>-- 

>tejun


Thanks,


Jiale

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