Re: [PATCH net V4 2/2] igb: offer a PTP Hardware Clock instead of the timecompare method

On Sat, Mar 24, 2012 at 2:51 AM, Richard Cochran
[off-list ref] wrote:

On Fri, Mar 23, 2012 at 03:39:08PM -0400, chetan loke wrote:

quoted

So, how is it working today? Because we could have tx and rx
completions on different CPUs. Is it not possible to have the
following race today - between timecompare_update->timecompare_offset
-> timecounter_readdelta of say Rx and timecounter_cyc2time from Tx?

I works (in the igb) because of the spinlock. You know, that thing
that you are so against using.

I meant, was there a lock before the PHC functionality in igb?

quoted

How about rate limiting at the PHC class driver level? And then it
will work across the board for all the adapters at the device level.

No, don't go there. Enough bikeshedding already. If you have a serious

can a user without root privileges use get/adj/set time ioctls for the
PHC functionality?

Thanks,
Richard

Chetan