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Date:   Sat, 30 Sep 2023 16:07:29 -0700
From:   Richard Cochran <richardcochran@gmail.com>
To:     Mahesh Bandewar <maheshb@google.com>
Cc:     Netdev <netdev@vger.kernel.org>,
        Linux <linux-kernel@vger.kernel.org>,
        David Miller <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Don Hatchett <hatch@google.com>,
        Yuliang Li <yuliangli@google.com>,
        Mahesh Bandewar <mahesh@bandewar.net>,
        Rahul Rameshbabu <rrameshbabu@nvidia.com>
Subject: Re: [PATCH 3/4] ptp: add ioctl interface for ptp_gettimex64any()
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References: <20230929023743.1611460-1-maheshb@google.com>
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On Sat, Sep 30, 2023 at 02:25:23PM -0700, Richard Cochran wrote:
> But how about a new system call instead?
> 
>     clock_compare(clockid_t a, clockid_t b);

It could have a third argument, n_samples, that would only be used for
"slow" clocks like PCIe MACs.  The system call would return the offset
from the shortest measurement (which is really what user space needs).

Thanks,
Richard