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Date: Mon, 17 Jun 2024 08:02:32 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Justin Lai <justinlai0215@realtek.com>
Cc: "davem@davemloft.net" <davem@davemloft.net>, "edumazet@google.com"
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Subject: Re: [PATCH net-next v20 07/13] rtase: Implement a function to
 receive packets
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On Mon, 17 Jun 2024 06:44:55 +0000 Justin Lai wrote:
> > > +             /* make sure discriptor has been updated */
> > > +             rmb();  
> > 
> > Barriers are between things. What is this barrier between?  
> 
> At the end of this do while loop, it fetches the next descriptor. This
> barrier is mainly used between fetching the next descriptor and using
> the next descriptor, to ensure that the content of the next descriptor is
> completely fetched before using it.

What does it mean to "fetch the next descriptor"? The prefetch?
Prefetches are not ordered at all.