Messages in this thread | | | Subject | Re: [RFC][PATCH] srcu: Implement call_srcu() | From | Peter Zijlstra <> | Date | Tue, 31 Jan 2012 14:50:07 +0100 |
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On Tue, 2012-01-31 at 15:47 +0200, Avi Kivity wrote:
> They really need to return quickly to userspace, and they really need to > perform some operation between rcu_assign_pointer() and returning, so no.
Bugger :/
> > > > Compile tested only!! :-) > > > > How much did synchronize_srcu_expedited() regress? Presumably your > compiler didn't tell you that.
Nope, quite a lot I figure.
> Can we get it back to speed by scheduling a work function on all cpus? > wouldn't that force a quiescent state and allow call_srcu() to fire? > > In kvm's use case synchronize_srcu_expedited() is usually called when no > thread is in a critical section, so we don't have to wait for anything > except the srcu machinery.
OK, I'll try and come up with means of making it go fast again ;-)
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