Vcore preemption spinning helpers
authorBarret Rhoden <brho@cs.berkeley.edu>
Tue, 20 Dec 2011 01:40:11 +0000 (17:40 -0800)
committerBarret Rhoden <brho@cs.berkeley.edu>
Tue, 20 Dec 2011 01:40:11 +0000 (17:40 -0800)
commitcd23d2f72688849540355b1911affc4a82412025
treed438918208a2ca98689d0136d8a554a23cb6c09b
parentc850b86f66ae18f19055fce62e2780d57c2e15a5
Vcore preemption spinning helpers

Provides two helpers for vcore code, which should be used when you spin
and wait on another vcore that could be preempted.  If you want to spin
a little before trying to see if you are spinning due to a preemption,
use the cpu_relax_vc() call.  o/w, directly call ensure_vcore_runs().
user/parlib/include/vcore.h
user/parlib/mcs.c
user/parlib/vcore.c