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Date:   Thu, 24 Jun 2021 09:20:29 -0700
From:   Richard Cochran <richardcochran@gmail.com>
To:     Min Li <min.li.xe@renesas.com>
Cc:     "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH net 1/2] ptp: idt82p33: optimize idt82p33_adjtime
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On Thu, Jun 24, 2021 at 02:38:46PM +0000, Min Li wrote:
> I have tested this change with ptp4l for by setting step_window to 48 (assuming 16 packets per second)
> for both 8265.2/8275.1 and they performed well.

Both of these patches assume that user space has a special
configuration that works together with the non-standard driver
behavior.

For this reason, I suggest making the new driver behavior optional,
with the default being the origin version that "just works".  In that
way, the admin/user can choose the special configuration on purpose,
and the default performance will not be degraded.

Thanks,
Richard