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Date:   Thu, 14 Dec 2023 09:24:11 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     JustinLai0215 <justinlai0215@realtek.com>
Cc:     "davem@davemloft.net" <davem@davemloft.net>,
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        "pabeni@redhat.com" <pabeni@redhat.com>,
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        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "andrew@lunn.ch" <andrew@lunn.ch>,
        Ping-Ke Shih <pkshih@realtek.com>,
        Larry Chiu <larry.chiu@realtek.com>
Subject: Re: [PATCH net-next v14 06/13] rtase: Implement .ndo_start_xmit
 function
Message-ID: <20231214092411.62661528@kernel.org>
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On Thu, 14 Dec 2023 13:00:29 +0000 JustinLai0215 wrote:
> > I don't see how this is called, the way you split the submission makes it a bit
> > hard to review, oh well. Anyway - if you pass the NAPI budget here - that's not
> > right, it may be 0, and you'd loop forever.
> > For Tx - you should try to reap some fixed number of packets, say 128, the
> > budget is for Rx, not for Tx.  
> 
> Even if the budget is 0, this function will not loop forever, it will just run all tx_left.
> Or what changes would you like us to make?

Ah, good point. It does seem a little accidental to me :S
In that case perhaps always consume all completed packets?
@budget should not constrain Tx completions directly, see:
https://www.kernel.org/doc/html/next/networking/napi.html