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

On Wed, Mar 21, 2012 at 11:00:59AM -0400, chetan loke wrote:

Once PHC->gettime goes live(aka exported to user space), we can't
really control how users will use it in their applications. There
could be 100+ apps all trying to get real-time from the network to do
some time-keeping stuff. They might pound the ioctls at high rate. The
last thing we would want is to self-induce a light weight DOS. What
Eric Dumazet mentioned in the very first patch set seems like a good
comment. seqlock or whatever it is we use for jiffies.

Can you please explain how using a seqlock could help here?

Thanks,
Richard