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Date:   Fri, 29 Jul 2022 08:44:48 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Hangyu Hua <hbh25y@gmail.com>
Cc:     davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
        kuniyu@amazon.co.jp, richard_siegfried@systemli.org,
        joannelkoong@gmail.com, socketcan@hartkopp.net,
        gerrit@erg.abdn.ac.uk, tomasz@grobelny.oswiecenia.net,
        dccp@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] dccp: put dccp_qpolicy_full() and dccp_qpolicy_push()
 in the same lock
Message-ID: <20220729084448.5a4492cc@kernel.org>
In-Reply-To: <f77aebb0-129a-bc73-0976-854eeea33ae5@gmail.com>
References: <20220727080609.26532-1-hbh25y@gmail.com>
        <20220728200139.1e7d9bc6@kernel.org>
        <f77aebb0-129a-bc73-0976-854eeea33ae5@gmail.com>
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On Fri, 29 Jul 2022 18:34:39 +0800 Hangyu Hua wrote:
> >> thread1--->lock
> >> thread1--->dccp_qpolicy_full: queue is full. drop a skb  
> > 
> > This linie should say "not full"?  
> 
> dccp_qpolicy_full only call dccp_qpolicy_drop when queue is full. You 
> can check out qpolicy_prio_full. qpolicy_prio_full will drop a skb to 
> make suer there is enough space for the next data. So I think it should 
> be "full" here.

Oh, I see what you're saying. That's unnecessarily complicated, 
I reckon. The "simple" policy suffers from the same problem and 
is easier to understand. Anyway, you already sent v2 and it doesn't
matter enough to warrant v3, so fine.