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Subject: Re: [PATCH 2/6] locking: Introduce range reader/writer lock
To: Davidlohr Bueso <dave@stgolabs.net>
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From: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Date: Thu, 13 Apr 2017 10:07:48 +0200
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On 06/04/2017 18:50, Davidlohr Bueso wrote:
> On Thu, 06 Apr 2017, Laurent Dufour wrote:
> 
>> How is 'seqnum' wrapping handled here ?
>> I'd rather see something like time_before() here, isn't it ?
> 
> Its a 64bit counter, no overflows.

I should have miss something, what prevents this 64bit counter to not
overflow ?
At some point of time, this counter could reach ~0UL and then 0UL, which
is breaking this check.