RE: [net-next, v2, 2/2] enetc: support PTP Sync packet one-step timestamping

[Claudiu Manoil <claudiu.manoil@nxp.com>]

>-----Original Message-----
>From: Jakub Kicinski <kuba@kernel.org>
>Sent: Thursday, April 8, 2021 7:07 PM
>To: Y.b. Lu <yangbo.lu@nxp.com>
>Cc: netdev@vger.kernel.org; David S . Miller <davem@davemloft.net>;
>Richard Cochran <richardcochran@gmail.com>; Claudiu Manoil
><claudiu.manoil@nxp.com>; Vladimir Oltean <vladimir.oltean@nxp.com>;
>Russell King <linux@armlinux.org.uk>
>Subject: Re: [net-next, v2, 2/2] enetc: support PTP Sync packet one-step
>timestamping
>
>On Thu, 8 Apr 2021 09:02:50 -0700 Jakub Kicinski wrote:
>> 		if (priv->flags & ONESTEP_BUSY) {
>> 			skb_queue_tail(&priv->tx_skbs, skb);
>> 			return ...;
>> 		}
>> 		priv->flags |= ONESTEP_BUSY;
>
>Ah, if you have multiple queues this needs to be under a separate
>spinlock, 'cause netif_tx_lock() won't be enough.

Hi Yangbo,

Please try test_and_set_bit_lock()/ clear_bit_unlock() based on Jakub's
suggestion, and see if it works for you / whether it can replace the mutex.

Thanks,
Claudiu