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From:   Kuniyuki Iwashima <kuniyu@amazon.com>
To:     <kuba@kernel.org>
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        <kuniyu@amazon.com>, <netdev@vger.kernel.org>, <pabeni@redhat.com>
Subject: Re: [PATCH v3 net 05/17] ratelimit: Fix data-races in ___ratelimit().
Date:   Mon, 22 Aug 2022 11:32:05 -0700
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From:   Jakub Kicinski <kuba@kernel.org>
Date:   Fri, 19 Aug 2022 17:04:46 -0700
> On Thu, 18 Aug 2022 11:26:41 -0700 Kuniyuki Iwashima wrote:
> > +	int interval = READ_ONCE(rs->interval);
> > +	int burst = READ_ONCE(rs->burst);
> 
> Also feels a little bit like papering over an issue if we read 
> two values separately.

Exactly, we have to protect it with a single lock.
Considering ___ratelimit() can be called in many paths, it seems better
to add a spin lock in struct ratelimit_state.

Thank you.