[sheepdog] [PATCH] sheep: fix handling of too old epoch in check_request

[Christoph Hellwig]

On Thu, May 31, 2012 at 04:40:31PM +0800, levin li wrote:
> it means the request needs to retry, but when to retry ? gateway will check req->rp.epoch
> which is peer's epoch, if gateway's system epoch is still old than peer's epoch, then the
> request should not be resend immediately, but put it into wait_rw_queue to wait for a new
> epoch, and if epoch is equal or newer than peer's epoch, then resend.
> 
> That's what this code does, I hope I made myself clear.

I think your explanation makes sense and should be documented in the
code so that people reading it can understand it.

I saw your patch doing this and it looks fine except for the lack of
comments.  Also can you wait for resubmitting it?  I'm about to finish
testing of a large series touching that area.