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Date:   Tue, 19 Jul 2022 17:49:15 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     LemmyHuang <hlm3280@163.com>
Cc:     edumazet@google.com, davem@davemloft.net, dsahern@kernel.org,
        pabeni@redhat.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] tcp: fix condition for increasing pingpong
 count
Message-ID: <20220719174915.48f830b4@kernel.org>
In-Reply-To: <20220719130136.11907-1-hlm3280@163.com>
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On Tue, 19 Jul 2022 21:01:37 +0800 LemmyHuang wrote:
> -	if (before(tp->lsndtime, icsk->icsk_ack.lrcvtime) &&
> +	if ((tp->lsndtime <= icsk->icsk_ack.lrcvtime) &&

Are you sure you don't need to take care of the values wrapping?
before() does that. You may want !after() if you want to allow equal.