tree beb63557074a7a5108bde2d0b26819691c83088a
parent 134d42d614768b2803e551621f6654dab1fdc2d2
author Alexander Graf <agraf@suse.de> 1385416014 +0100
committer Anthony Liguori <aliguori@amazon.com> 1385440511 -0800

PPC: Make BookE FIT/WDT timers more lazy

Today we fire FIT and WDT timer events every time the respective bit
position in TB flips from 0 -> 1.

However, there is no need to do this if the end result would be that
we're changing a TSR bit that is set to 1 to 1 again. No guest visible
change would have occured.

So whenever we see that the TSR bit to our timer is already set, don't
even bother to update the timer that would potentially fire it off.

However, we do need to make sure that we update our timer that notifies
us of the TB flip when the respective TSR bit gets unset. In that case
we do care about the flip and need to notify the guest again. So add
a callback into our timer handlers when TSR bits get unset.

This improves performance for me when the guest is busy processing things.

Signed-off-by: Alexander Graf <agraf@suse.de>
Message-id: 1385416015-22775-2-git-send-email-agraf@suse.de
Signed-off-by: Anthony Liguori <aliguori@amazon.com>