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Date: Tue, 18 Jan 2011 08:19:34 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: [Qemu-devel] Re: [PATCH v2 0/5] iohandlers: Add support for
 enabling/disabling individual handlers
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To: Amit Shah <amit.shah@redhat.com>
Cc: Paul Brook <paul@codesourcery.com>, qemu list <qemu-devel@nongnu.org>, Gerd Hoffmann <kraxel@redhat.com>

On 01/18/2011 05:56 AM, Amit Shah wrote:
> On (Mon) Jan 17 2011 [08:57:16], Anthony Liguori wrote:
>    
>>> Also -- this patchset was prompted by a bug in qemu chardevs that
>>> freezes guests if they write faster than the chardevs can consume.
>>> What should the strategy on fixing that bug be?
>>>        
>> Fix the loop API such that we're not just fixing one bug but that we
>> can address a bunch of other bugs that are out there.
>>      
> But what's the right fix?
>
> * Pull in glib or some other library
> * Mimic API from some other library
>    

1) get rid of poll callbacks

These kill us right now because it makes it impossible to use poll/epoll 
or to use some other API.

2) switch to a single callback and an event mask

We can't do this without (1) because the can_read callback takes a 
different signature.  But read/write callbacks can be a single callback 
(but it needs to be changed to accept an event mask).

3) allow the event mask to be changed via a new API

This gives the functionality you're looking for while making a huge 
improvement to the internal API.

A quick python/perl script can probably do 90% of the work here.

Regards,

Anthony Liguori

> 		Amit
>