On Mon, 04 Sep 2017, Peter Zijlstra wrote:
For testing its trivial to hack your kernel and I don't feel this is something an Admin can make reasonable decisions about. So why? In general less knobs is better.
+1. Also, note how b8fa70b51aa (xen, pvticketlocks: Add xen_nopvspin parameter to disable xen pv ticketlocks) has no justification as to why its wanted in the first place. The only thing I could find was from 15a3eac0784 (xen/spinlock: Document the xen_nopvspin parameter): "Useful for diagnosing issues and comparing benchmarks in over-commit CPU scenarios." So I vote for no additional knobs, specially for such core code. Thanks, Davidlohr
