netdev - RE: [PATCH net-next v6 1/4] net: wangxun: Add support for PTP clock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <03a901db7d22$24628cc0$6d27a640$@trustnetic.com>
Date: Wed, 12 Feb 2025 15:45:52 +0800
From: Jiawen Wu <jiawenwu@...stnetic.com>
To: "'Jakub Kicinski'" <kuba@...nel.org>
Cc: <andrew+netdev@...n.ch>,
	<davem@...emloft.net>,
	<edumazet@...gle.com>,
	<pabeni@...hat.com>,
	<richardcochran@...il.com>,
	<linux@...linux.org.uk>,
	<horms@...nel.org>,
	<jacob.e.keller@...el.com>,
	<netdev@...r.kernel.org>,
	<vadim.fedorenko@...ux.dev>,
	<mengyuanlou@...-swift.com>
Subject: RE: [PATCH net-next v6 1/4] net: wangxun: Add support for PTP clock

On Wed, Feb 12, 2025 8:07 AM, Jakub Kicinski wrote:
> On Sat,  8 Feb 2025 11:13:45 +0800 Jiawen Wu wrote:
> > + * wx_ptp_tx_hwtstamp_work
> > + * @work: pointer to the work struct
> > + *
> > + * This work item polls TSC_1588_CTL valid bit to determine when a Tx hardware
> > + * timestamp has been taken for the current skb. It is necessary, because the
> > + * descriptor's "done" bit does not correlate with the timestamp event.
> 
> Why not use the aux_work for this?
> IIUC aux_work often has lower latency since it's a dedicated thread.

I think this task for checking TX timestamp is immediate and continuous
after the skbuff is sent, and can be stopped after polling a valid timestamp.
But aux_work for detecting overflow and error cases is a periodic task that
is always carried out. It looks a little bit clearer if they were separated, but
I could also try to merge it into aux_work if I need to.