Re: [PATCH net-next 8/9] net: hns3: add support for queue bonding mode of flow director

From: "shenjian (K)" <shenjian15@huawei.com>
To: Jakub Kicinski <kuba@kernel.org>
Cc: Huazhong Tan <tanhuazhong@huawei.com>,
	Alexander Duyck <alexander.duyck@gmail.com>,
	<davem@davemloft.net>, <netdev@vger.kernel.org>,
	<salil.mehta@huawei.com>, <yisen.zhuang@huawei.com>,
	<huangdaode@huawei.com>, <linuxarm@openeuler.org>
Subject: Re: [PATCH net-next 8/9] net: hns3: add support for queue bonding mode of flow director
Date: Sat, 19 Jun 2021 11:20:44 +0800	[thread overview]
Message-ID: <d276b445-ae19-cdf3-f2fc-cd32b91da02f@huawei.com> (raw)
In-Reply-To: <20210618150156.0ffc88a0@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>


在 2021/6/19 6:01, Jakub Kicinski 写道:
> On Fri, 18 Jun 2021 09:18:21 +0800 shenjian (K) wrote:
>> Hi  Jakub，
>>
>>
>> 在 2021/3/18 9:28, Jakub Kicinski 写道:
>>> On Thu, 18 Mar 2021 09:02:54 +0800 Huazhong Tan wrote:
>>>> On 2021/3/16 4:04, Jakub Kicinski wrote:
>>>>> On Mon, 15 Mar 2021 20:23:50 +0800 Huazhong Tan wrote:
>>>>>> From: Jian Shen <shenjian15@huawei.com>
>>>>>>
>>>>>> For device version V3, it supports queue bonding, which can
>>>>>> identify the tuple information of TCP stream, and create flow
>>>>>> director rules automatically, in order to keep the tx and rx
>>>>>> packets are in the same queue pair. The driver set FD_ADD
>>>>>> field of TX BD for TCP SYN packet, and set FD_DEL filed for
>>>>>> TCP FIN or RST packet. The hardware create or remove a fd rule
>>>>>> according to the TX BD, and it also support to age-out a rule
>>>>>> if not hit for a long time.
>>>>>>
>>>>>> The queue bonding mode is default to be disabled, and can be
>>>>>> enabled/disabled with ethtool priv-flags command.
>>>>> This seems like fairly well defined behavior, IMHO we should have a full
>>>>> device feature for it, rather than a private flag.
>>>> Should we add a NETIF_F_NTUPLE_HW feature for it?
>>> It'd be better to keep the configuration close to the existing RFS
>>> config, no? Perhaps a new file under
>>>
>>>     /sys/class/net/$dev/queues/rx-$id/
>>>
>>> to enable the feature would be more appropriate?
>>>
>>> Otherwise I'd call it something like NETIF_F_RFS_AUTO ?
>> I noticed that the enum NETIF_F_XXX_BIT has already used 64 bits since
>>
>> NETIF_F_HW_HSR_DUP_BIT being added, while the prototype of
>> netdev_features_t
>>
>> is u64.   So there is no useable bit for new feature if I understand
>> correct.
>>
>> Is there any solution or plan for it ?
> I think you'll need to start a new word.
> .
>
what about define a netdev feature bitmap

#define __DECLARE_NETDEV_FEATURE_T(name)        \
     DECLARE_BITMAP(name, NETDEV_FEATURE_COUNT)

like __ETHTOOL_DECLARE_LINK_MODE_MASK does