32  * occur if a wakeup IRQ arrives and attempts to acquire the lock.
74 	 * If the vCPU wasn't on the wakeup list and wasn't migrated, then the  in vmx_vcpu_pi_load()
88 	 * If the vCPU was waiting for wakeup, remove the vCPU from the wakeup  in vmx_vcpu_pi_load()
96 		 * In addition to taking the wakeup lock for the regular/IRQ  in vmx_vcpu_pi_load()
100 		 * with both the scheduler and the wakeup handler.  in vmx_vcpu_pi_load()
126 		 * descriptor was modified on "put" to use the wakeup vector.  in vmx_vcpu_pi_load()
160  * WAKEUP as the notification vector in the PI descriptor.
171 	 * Acquire the wakeup lock using the "sched out" context to workaround  in pi_enable_wakeup_handler()
173 	 * various per-CPU scheduler locks.  When the wakeup handler runs, it  in pi_enable_wakeup_handler()
174 	 * holds this CPU's wakeup lock while calling try_to_wake_up(), which  in pi_enable_wakeup_handler()
179 	 * entirety of the sched_out critical section, i.e. the wakeup handler  in pi_enable_wakeup_handler()
192 		/* set 'NV' to 'wakeup vector' */  in pi_enable_wakeup_handler()
198 	 * Send a wakeup IPI to this CPU if an interrupt may have been posted  in pi_enable_wakeup_handler()
200 	 * will arrive on the non-wakeup vector.  An IPI is needed as calling  in pi_enable_wakeup_handler()
232 	 * enable the wakeup handler so that notification IRQ wakes the vCPU as  in vmx_vcpu_pi_put()
233 	 * expected.  There is no need to enable the wakeup handler if the vCPU  in vmx_vcpu_pi_put()
238 	 * If the wakeup handler isn't being enabled, Suppress Notifications as  in vmx_vcpu_pi_put()
294  * blocking vCPUs may scheduled out without reconfiguring PID.NV to the wakeup