Thread (37 messages) 37 messages, 3 authors, 2012-03-30

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

From: Richard Cochran <richardcochran@gmail.com>
Date: 2012-03-24 06:51:49

On Fri, Mar 23, 2012 at 03:39:08PM -0400, chetan loke wrote:
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.
So yes, rate limiting ioctls seems like a good idea.
No, that is a terrible idea.
 
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
performance issue, please post a test case, and we will look for a
solution.

Thanks,
Richard



------------------------------------------------------------------------------
This SF email is sponsosred by:
Try Windows Azure free for 90 days Click Here 
http://p.sf.net/sfu/sfd2d-msazure
_______________________________________________
E1000-devel mailing list
E1000-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/e1000-devel
To learn more about Intel&#174; Ethernet, visit http://communities.intel.com/community/wired
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help