Re: [Xen-devel] Singleshot timer firing late

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 19.05.14 at 15:08, <ross.lagerwall@xxxxxxxxxx> wrote:
> Here's another patch which programs the timer to the deadline of the
> closest timer if it is further than 50us ahead, otherwise it sets it
> 50us ahead. This way a single event fires on time and events don't fire
> early.  I think this behaves like Linux clockevent's min_delta_ns.

Yes, this one I can see us taking if submitted in proper shape. But
if at all possible I'd like you to get Keir's input here too, as he may
recall further details on what lead to 116d62ddfd11.

As a technical detail - I think I'd prefer you to not use the latched
(and stale, due to an unknown number of timers having run between
NOW() being used and the consumer here) value "now", but rather
re-latch now right before the assignment. This in particular shrinks
the number of cases where the MAX() degenerates to "deadline"
because of "now + timer_slop" already lying in the past.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel