Re: [PATCH 1/1] Xen ARINC 653 Scheduler (updated to add support for CPU pools)

[Keir Fraser <keir.fraser@eu.citrix.com>]

On 16/06/2010 17:25, "Kathy Hadley" <Kathy.Hadley@dornerworks.com> wrote:

> Keir,
>   I only saw the .init function called once.  I downloaded xen-unstable on May
> 27.  Were your updates after that?

My changes were done before May 27, and that ties in with you seeing .init
called only once. That being the case, you should not see multiple different
ops structures ('struct scheduler' instances). The only ops struct that
should exist in the system in this case should be the one statically defined
near the top of common/schedule.c.

 -- Keir

>   Thanks,
> Kathy Hadley
> 
> 
>> -----Original Message-----
>> From: Keir Fraser [mailto:keir.fraser@eu.citrix.com]
>> Sent: Wednesday, June 16, 2010 12:20 PM
>> To: George Dunlap; Kathy Hadley
>> Cc: xen-devel@lists.xensource.com; Juergen Gross
>> Subject: Re: [Xen-devel] [PATCH 1/1] Xen ARINC 653 Scheduler (updated
>> to add support for CPU pools)
>> 
>> On 16/06/2010 17:14, "George Dunlap" <George.Dunlap@eu.citrix.com>
>> wrote:
>> 
>>>>  I actually tried the xmalloc() method first.  I found that when the
>>>> .adjust_global function was called, the address of the "ops" data
>> structure
>>>> passed to that function was different from the address of the "ops"
>> data
>>>> structure when the .init function was called.  I wanted to use
>> .adjust_global
>>>> to modify the data structure that was created when the .init
>> function was
>>>> called, but I could not figure out a way to get the address of the
>> second
>>>> data structure.  Suggestions?
>>> 
>>> It's been a month or two since I trawled through the cpupools code;
>>> but I seem to recall that .init is called twice -- once for the
>>> "default pool" (cpupool0), and once for an actually in-use pool.
>>> (Juergen, can you correct me if I'm wrong?)  Is it possible that
>>> that's the difference in the pointers that you're seeing?
>> 
>> Oh yes, that was the old behaviour. I took a hatchet to the
>> scheduler/cpupool interfaces a few weeks ago and now we should only
>> initialise the scheduler once, unless extra cpupools are manually
>> created.
>> The fact that Kathy is seeing two different ops structures probably
>> indicates that her xen-unstable tree is very out of date. Which may
>> also
>> mean that the patch will not apply to current tip.
>> 
>>  -- Keir
>> 
>