kdb-4.1 & RedHat 9.0 [was Re: Automatic detection of O(1) scheduler in latest kdb]

[Nicholas Wourms <nwourms@xxxxxxxxxxxxx>]

Keith Owens wrote:
> On Tue, 08 Apr 2003 11:28:54 -0400,
> Nicholas Wourms <nwourms@xxxxxxxxxxxxx> wrote:
>
>>According to the ChangLog, the kdb code now has automatic
>>recognition support for the O(1) scheduler.  However, in
>>kdb_bt.c, there is an ungaurded "init_tasks".  This causes
>>problems for users of O(1), because the scheduler removes
>>init_tasks in favor of something else.  Just thought I'd
>>report this.
>
>
> It depends which O(1) scheduler you are using, there are 
multiple
> variants.  In the version that SGI use on the Altix 
boxes, init_tasks
> still exists.
>
> However this has got to be enough of a nuisance that the 
next version
> of kdb will drop init_tasks and use its own data areas to 
track the
> idle tasks.
>

Just for kicks, I tried compiling the latest kdb into the 
RedHat 9.0 source package.  Unfortunately, the 
signal/threading backport for NPTL seems to be causing even 
more undefined/undeclared function calls then the O(1) 
scheduler already does alone.  Specifically, it seems as if:

init_tasks (we already know about this one)
task_has_cpu
runqueue_lock

are no longer used, having been replaced by per-cpu based 
versions.  Seeing as how this backport is essential for 
NPTL, will the next kdb be able to work with patch & Ingo's 
O(1) (or RedHat 9.0 sources for that matter)?  It'd be a 
bummer to have to choose between the two (or have to go with 
an older kdb)...

I tried, but unfortunately was unsuccessful, in my attempts 
to get it working properly on a SMP box.  I did get it to 
compile, but I know that my lack of understanding w.r.t. to 
kernel scheduling and threading led to kdb not actually 
working properly.  I googled for some conversion samples, 
but unfortunately converting from the old functions & 
structs to the new ones seems to require more then just a 
passing bit of knowledge.  Has anyone else tried getting it 
working with RedHat 9 sources?  Any workarounds or solutions?

Cheers,
Nicholas