Subject: Re: port-xen/29999: ctrl_if_interrupt IPL problem
To: None <port-xen-maintainer@netbsd.org, gnats-admin@netbsd.org,>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: netbsd-bugs
Date: 04/19/2005 12:46:02
The following reply was made to PR port-xen/29999; it has been noted by GNATS.

From: Manuel Bouyer <bouyer@antioche.lip6.fr>
To: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Cc: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>, gnats-bugs@NetBSD.org,
	port-xen-maintainer@NetBSD.org, gnats-admin@NetBSD.org,
	netbsd-bugs@NetBSD.org
Subject: Re: port-xen/29999: ctrl_if_interrupt IPL problem
Date: Tue, 19 Apr 2005 14:45:02 +0200

 On Tue, Apr 19, 2005 at 01:38:10PM +0100, Christian Limpach wrote:
 > > Will HYPERVISOR_block() return when there is an event pending, even if
 > > evtchn_upcall_mask is nonzero ?
 > 
 > yes, HYPERVISOR_block() will reenable events in a race-free manner, i.e.
 > you want to call HYPERVISOR_block() with events disabled and it will return
 > immediately if there are already pending events.
 
 ha, but events will be reenabled (evtchn_upcall_mask will be reset to 0),
 right ? If so we can't really run in complete polling mode ...
 
 --
 Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
      NetBSD: 26 ans d'experience feront toujours la difference
 --