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Subject: Re: [PATCH net-next 0/4] net: ethtool: Untangle PHYLIB dependency
To:     Jakub Kicinski <kuba@kernel.org>, Andrew Lunn <andrew@lunn.ch>
Cc:     Michal Kubecek <mkubecek@suse.cz>, netdev@vger.kernel.org,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        open list <linux-kernel@vger.kernel.org>
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 <20200702163424.GG752507@lunn.ch>
 <20200702093545.5ee3371a@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
Message-ID: <47965786-9a12-6f09-cf23-1d342334fbc0@gmail.com>
Date:   Thu, 2 Jul 2020 09:43:45 -0700
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On 7/2/2020 9:35 AM, Jakub Kicinski wrote:
> On Thu, 2 Jul 2020 18:34:24 +0200 Andrew Lunn wrote:
>> On Thu, Jul 02, 2020 at 05:56:52PM +0200, Michal Kubecek wrote:
>>> On Wed, Jul 01, 2020 at 09:29:38PM -0700, Florian Fainelli wrote:  
>>>> Hi all,
>>>>
>>>> This patch series untangles the ethtool netlink dependency with PHYLIB
>>>> which exists because the cable test feature calls directly into PHY
>>>> library functions. The approach taken here is to utilize a new set of
>>>> net_device_ops function pointers which are automatically set to the PHY
>>>> library variants when a network device driver attaches to a PHY device.  
>>>
>>> I'm not sure about the idea of creating a copy of netdev_ops for each
>>> device using phylib. First, there would be some overhead (just checked
>>> my 5.8-rc3 kernel, struct netdev_ops is 632 bytes). Second, there is
>>> quite frequent pattern of comparing dev->netdev_ops against known
>>> constants to check if a network device is of certain type; I can't say
>>> for sure if it is also used with devices using phylib in existing code
>>> but it feels risky.  
>>
>> I agree with Michal here. I don't like this.
>>
>> I think we need phylib to register a set of ops with ethtool when it
>> loads. It would also allow us to clean up phy_ethtool_get_strings(),
>> phy_ethtool_get_sset_count(), phy_ethtool_get_stats().
> 
> +1

OK, that makes sense, I will work on that.
-- 
Florian