Re: [PATCH] percpu-refcount: relax limit on percpu_ref_reinit()

[Tejun Heo]

Hello,

On Tue, Sep 11, 2018 at 12:40:36PM +0800, jianchao.wang wrote:
> (long)(sum (every cpu's refcounter)) + atomic refcounter
> 
> and when switch to atomic mode, there could be value left in atomic refcounter.
> then the unsigned long percpu refcounter cound be decreased from 0.

It can always do that.  Imagine a task getting a ref on one cpu,
migrating and putting it on another.  The only thing which matters is
that the sum of everything adds upto what it should be.

Thanks.

-- 
tejun