[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Mon, 12 Dec 2022 23:24:22 +0000
From: "Kolacinski, Karol" <karol.kolacinski@...el.com>
To: "richardcochran@...il.com" <richardcochran@...il.com>
CC: "davem@...emloft.net" <davem@...emloft.net>,
"edumazet@...gle.com" <edumazet@...gle.com>,
"G, GurucharanX" <gurucharanx.g@...el.com>,
"kuba@...nel.org" <kuba@...nel.org>,
"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
"pabeni@...hat.com" <pabeni@...hat.com>,
"Nguyen, Anthony L" <anthony.l.nguyen@...el.com>
Subject: Re: [PATCH net 1/4] ice: Create a separate kthread to handle ptp
extts work
>On 12/7/2022 4:27 PM, Richard Cochran wrote:
>> On Wed, Dec 07, 2022 at 01:10:37PM -0800, Tony Nguyen wrote:
>>> From: Anatolii Gerasymenko anatolii.gerasymenko@...el.com
>>>
>>> ice_ptp_extts_work() and ice_ptp_periodic_work() are both scheduled on
>>> the same kthread_worker pf.ptp.kworker. But, ice_ptp_periodic_work()
>>> sends messages to AQ and waits for responses. This causes
>>> ice_ptp_extts_work() to be blocked while waiting to be scheduled. This
>>> causes problems with the reading of the incoming signal timestamps,
>>> which disrupts a 100 Hz signal.
>>>
>>> Create an additional kthread_worker pf.ptp.kworker_extts to service only
>>> ice_ptp_extts_work() as soon as possible.
>>
>> Looks like this driver isn't using the do_aux_work callback. That
>> would provide a kthread worker for free. Why not use that?
According to do_aux_work description, it is used to do 'auxiliary (periodic)
operations'.
ice_ptp_extts_work is not exactly periodic as the work is queued only when the
interrupt comes.
Thanks,
Karol
Powered by blists - more mailing lists