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Message-ID: <f714f3e2-44b0-e0f9-0b99-2878ec12cb56@nbd.name>
Date:   Tue, 8 Nov 2022 07:01:29 +0100
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Subject: Re: [PATCH 05/14] net: dsa: tag_mtk: assign per-port queues
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To:     Vladimir Oltean <olteanv@gmail.com>
Cc:     netdev@vger.kernel.org, Sean Wang <sean.wang@mediatek.com>,
        Landen Chao <Landen.Chao@mediatek.com>,
        DENG Qingfang <dqfext@gmail.com>, Andrew Lunn <andrew@lunn.ch>,
        Vivien Didelot <vivien.didelot@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20221107185452.90711-1-nbd@nbd.name>
 <20221107185452.90711-5-nbd@nbd.name> <20221107212209.4pmoctkze4m2ggbv@skbuf>
From:   Felix Fietkau <nbd@nbd.name>
In-Reply-To: <20221107212209.4pmoctkze4m2ggbv@skbuf>
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On 07.11.22 22:22, Vladimir Oltean wrote:
> On Mon, Nov 07, 2022 at 07:54:43PM +0100, Felix Fietkau wrote:
>> Keeps traffic sent to the switch within link speed limits
>> 
>> Signed-off-by: Felix Fietkau <nbd@nbd.name>
>> ---
>>  net/dsa/tag_mtk.c | 3 +++
>>  1 file changed, 3 insertions(+)
>> 
>> diff --git a/net/dsa/tag_mtk.c b/net/dsa/tag_mtk.c
>> index 415d8ece242a..445d6113227f 100644
>> --- a/net/dsa/tag_mtk.c
>> +++ b/net/dsa/tag_mtk.c
>> @@ -25,6 +25,9 @@ static struct sk_buff *mtk_tag_xmit(struct sk_buff *skb,
>>  	u8 xmit_tpid;
>>  	u8 *mtk_tag;
>>  
>> +	/* Reserve the first three queues for packets not passed through DSA */
>> +	skb_set_queue_mapping(skb, 3 + dp->index);
>> +
> 
> Should DSA have to care about this detail, or could you rework your
> mtk_select_queue() procedure to adjust the queue mapping as needed?
I'm setting the queue here so that I don't have to add the extra 
overhead of parsing the payload in the ethernet driver.
For passing the queue, I used a similar approach as tag_brcm.c and
drivers/net/ethernet/broadcom/bcmsysport.c

- Felix