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 10:33:02
The following reply was made to PR port-xen/29999; it has been noted by GNATS.

From: Manuel Bouyer <bouyer@antioche.lip6.fr>
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
Cc: 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 12:32:17 +0200

 On Tue, Apr 19, 2005 at 06:25:14PM +0900, YAMAMOTO Takashi wrote:
 > > Not here, xenconscn_getc() calls HYPERVISOR_yield() when it waits for
 > > input, so it won't consume CPU. But HYPERVISOR_yield() won't return unless
 > > interrupts are enabled.
 > 
 > "interrupts" in what sense?
 > i thought HYPERVISOR_yield left the calling domain runnable
 > so it would be scheduled sooner or later.
 
 Hum, I need to look at this again. From what I remember, if I leaved
 the events blocked, HYPERVISOR_yield() would never return.
 But maybe I had something else wrong in my code.
 
 --
 Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
      NetBSD: 26 ans d'experience feront toujours la difference
 --