2.6.26.8-rt15

2.6.26.8-rt15

[Steven Rostedt]

We are pleased to announce the 2.6.26.8-rt15 tree which can be
downloaded from the following location:

  http://rt.et.redhat.com/download/

Information on the RT patch can be found at:

  http://rt.wiki.kernel.org/index.php/Main_Page

Changes since 2.6.26.6-rt14

 - x86, mm: fix pte_free()  (Peter Zijlstra)

 - hrtimer: prevent negative expiry value after clack_was_set
 		(Thomas Gleixner)

 - Fixed confusing Kconfig label of WAKEUP_LATENCY_HIST
	 	(Carsten Emde)

 - x86: remove redundant local_irq_enable in handle_singal
		(Carsten Emde)

 - trace: warn if irqs already enabled in irqs_off latency check
		(Carsten Emde)

to build the 2.6.26.8-rt15 tree, the following patches should be applied:

  http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.26.tar.bz2
  http://kernel.org/pub/linux/kernel/v2.6/patch-2.6.26.8.bz2
  http://rt.et.redhat.com/download/patch-2.6.26.8-rt15.bz2


And like always, my RT version of Matt Mackall's ketchup will get this
for you nicely:

  http://people.redhat.com/srostedt/rt/tools/ketchup-0.9.8-rt3


The broken out patches are also available.

***************************************************************
***************************************************************
******  COMING SOON !!! COMING SOON !!! COMING SOON !!! *******
******  COMING SOON !!! COMING SOON !!! COMING SOON !!! *******
***************************************************************
***************************************************************

The RT git tree is almost ready!  It is currently based off of 2.6.28,
until it becomes a little more stable. You can down load it now from the
git repo:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-rt.git

It boots on x86_64. A few more patches still need to be applied, but the
majority of them have been incorporated. Work on the non x86 archs also
needs to be done.

Once the git tree is pretty stable I will release a 2.6.28-rt1 patch,
make a v2.6.28-rt branch and then go right in sync with the mainline
tree.

Feel free to download it now and give it a try. And you can send me any
crashes that you see.


-- Steve

Re: 2.6.26.8-rt15

[Luis Henriques]

On Sat, Jan 31, 2009 at 02:34:10AM -0500, Steven Rostedt wrote:
> We are pleased to announce the 2.6.26.8-rt15 tree which can be
> downloaded from the following location:
> 
>   http://rt.et.redhat.com/download/
> 
> Information on the RT patch can be found at:
> 
>   http://rt.wiki.kernel.org/index.php/Main_Page

I'm having compilation issues with this new patch.  Here's the error I got:

In file included from
/root/lmcorrei/linux/linux-2.6.26.8-rt15/kernel/sched.c:1701:
/root/lmcorrei/linux/linux-2.6.26.8-rt15/kernel/sched_rt.c: In
function 'inc_rt_tasks':
/root/lmcorrei/linux/linux-2.6.26.8-rt15/kernel/sched_rt.c:434: error:
'struct rq' has no member named 'online'

Now, function in question has the following code:

static inline
void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
{
        WARN_ON(!rt_prio(rt_se_prio(rt_se)));
        rt_rq->rt_nr_running++;
#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
        if (rt_se_prio(rt_se) < rt_rq->highest_prio) {
                struct rq *rq = rq_of_rt_rq(rt_rq);
                rt_rq->highest_prio = rt_se_prio(rt_se);

                if (rq->online)
                        cpupri_set(&rq->rd->cpupri, rq->cpu,
                                   rt_se_prio(rt_se));
        }
#endif

The issue is that the 'online' member is actually defined only if CONFIG_SMP is
enabled and in my config I do not have it but I have CONFIG_RT_GROUP_SCHED.

I am not sending any patch because I actually do not know what is the best way
to solve this issue since I am not (yet!) a sched expert.  However, I forsee two
possible solutions:

 1. Nest another #ifdef inside the first one, so that the code is only compiled
    when CONFIG_SMP option is set (which will result in ugly code)
 2. Define 'online' member in structure outside of the CONFIG_SMP (which, I
    believe, is not an optimal solution)

Regards,
-- 
Luis Henriques

Re: 2.6.26.8-rt15

[Steven Rostedt]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 791 bytes --]


On Mon, 2 Feb 2009, Gregory Haskins wrote:

> 
> Hi Luis,
> 
> >>>> Luis Henriques <henrix@sapo.pt> 2/2/2009 2:06 PM >>>
> >On Sat, Jan 31, 2009 at 02:34:10AM -0500, Steven Rostedt wrote:
> >> We are pleased to announce the 2.6.26.8-rt15 tree which can be
> >> downloaded from the following location:
> >>
> >>   http://rt.et.redhat.com/download/
> >>
> >> Information on the RT patch can be found at:
> >>
> >>   http://rt.wiki.kernel.org/index.php/Main_Page
> >
> > I'm having compilation issues with this new patch.  Here's the error I
> got:
> 
> 
> I have already fixed this in -tip.git and -rt.git, but it hasnt been
> backported to 26-rt yet.  I will take care of getting these patches
> backported for Steven to include in -rt16.

Thanks Greg!

-- Steve