Re: [PATCH v2 tip/core/rcu 0/13] Miscellaneous fixes for 4.12

[Paul E. McKenney]

On Wed, Apr 19, 2017 at 01:28:45PM +0200, Peter Zijlstra wrote:
> 
> So the thing Maz complained about is because KVM assumes
> synchronize_srcu() is 'free' when there is no srcu_read_lock() activity.
> This series 'breaks' that.
> 
> I've not looked hard enough at the new SRCU to see if its possible to
> re-instate that feature.

And with the fix I gave Maz, the parallelized version is near enough
to being free as well.  It was just a stupid bug on my part: I forgot
to check for expedited when scheduling callbacks.

							Thanx, Paul