From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
Subject: Re: [Intel-wired-lan] [RFC v2 net-next 01/10] net: Add a new socket
 option for a future transmit time.
Date: Wed, 31 Jan 2018 16:49:36 -0800
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Cc: netdev@vger.kernel.org, john.stultz@linaro.org,
        Richard Cochran <rcochran@linutronix.de>, jiri@resnulli.us,
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To: Richard Cochran <richardcochran@gmail.com>,
        Miroslav Lichvar <mlichvar@redhat.com>
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Hi,


On 01/18/2018 09:13 AM, Richard Cochran wrote:
> On Thu, Jan 18, 2018 at 09:42:27AM +0100, Miroslav Lichvar wrote:
>> In the discussion about the v1 patchset, there was a question if the
>> cmsg should include a clockid_t. Without that, how can an application
>> prevent the packet from being sent using an incorrect clock, e.g.
>> the system clock when it expects it to be a PHC, or a different PHC
>> when the socket is not bound to a specific interface?
> 
> Right, the clockid_t should be passed in through the CMSG along with
> the time.

While implementing this today it crossed my mind that why don't we have the
clockid_t set per socket (e.g. as an argument to SO_TXTIME) instead of per packet?

The only use-case that we could think of that would be 'blocked' was using
sendmmsg() to send a packet to different interfaces with a single syscall, but
I'm not sure how common that is.

What do you think?

Thanks,
Jesus


>  
> Thanks,
> Richard
>