>>> On 09.03.16 at 17:10, <dario.faggi...@citrix.com> wrote: > On Tue, 2016-03-08 at 19:09 +0000, Wei Liu wrote: >> On Sun, Mar 06, 2016 at 11:55:55AM -0600, Chong Li wrote: >> >> > + spin_lock_irqsave(&prv->lock, flags); >> > + svc = rt_vcpu(d->vcpu[local_sched.vcpuid]); >> > + svc->period = period; >> > + svc->budget = budget; >> > + spin_unlock_irqrestore(&prv->lock, flags); >> > + >> And this locking pattern seems sub-optimal. You might be able to move >> the lock and unlock outside the while loop? >> > Yes, unless I'm missing something, that looks possible to me, and would > save a lot of acquire/release ping pong on the lock.
Well, there are guest memory accesses (which may fault) in the loop body. While this may work right now, I don't think doing so is a good idea. > And yet, I'm not sure doing (for large guests) batches of 64 iterations > with (as of now) interrupts disabled. This I'd be much less worried about as long as what's inside the loop body was a reasonably short code sequence. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
