qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] Re: [PATCH 11/19] use a bottom half to run timers


From: malc
Subject: [Qemu-devel] Re: [PATCH 11/19] use a bottom half to run timers
Date: Tue, 5 Jan 2010 18:23:34 +0300 (MSK)

On Tue, 5 Jan 2010, Michael S. Tsirkin wrote:

> On Mon, Jan 04, 2010 at 05:54:13PM -0600, Anthony Liguori wrote:
> > On 01/04/2010 02:01 PM, Michael S. Tsirkin wrote:
> >> On Mon, Jan 04, 2010 at 02:24:53PM -0600, Anthony Liguori wrote:
> >>    
> >>> On 12/21/2009 02:09 AM, Paolo Bonzini wrote:
> >>>      
> >>>> Make the timer subsystem register its own bottom half instead of
> >>>> placing the bottom half code in the heart of the main loop.  To
> >>>> test if an alarm timer is pending, just check if the bottom half is
> >>>> scheduled.
> >>>>
> >>>> Signed-off-by: Paolo Bonzini<address@hidden>
> >>>>        
> >>> I'm not a huge fan of this for a couple reasons.  The first is that it
> >>> introduces a subtle semantic change.  Previously, timers always ran
> >>> before bottom halves whereas after this change, timers may run after
> >>> some bottoms halves but before others.  While this should be okay in
> >>> principle, in practice, I'm sure it'll introduce regressions.  I'd be
> >>> very surprised if cris wasn't affected by this.
> >>>
> >>> But more importantly, I think timer dispatch needs to be part of the
> >>> select loop.  malc has a git tree that replaces host alarm timers with
> >>> select() timeouts.
> >>>      
> >> Where is that tree?
> >>    
> >
> > http://repo.or.cz/w/qemu/malc.git  mtloop
> 
> Don't seem to see anything there.
> malc?

Yes?
 
> >> IMO we need that, I am not sure all code is as signal-safe
> >> as it should be. At least crashes that I saw with winxp install
> >> seem to be related to signal handling.
> >>    
> >
> > Regards,
> >
> > Anthony Liguori
> 

-- 
mailto:address@hidden




reply via email to

[Prev in Thread] Current Thread [Next in Thread]