RE: [Alsa-devel] Re: 2.6.15-rt18, alsa sequencer, rosegarden -> alsa hangs

From: karsten wiese
Date: Tue Mar 07 2006 - 20:26:47 EST



--- Ingo Molnar <mingo@xxxxxxx> schrieb:

>
> * Fernando Lopez-Lezcano <nando@xxxxxxxxxxxxxxxxxx>
> wrote:
>
> > The symptoms are as follows:
> > - start jack using qjackctl
> > - start qsynth (gui front end for fluidsynth, a
> synth)
> > - start rosegarden (midi sequencer and audio
> recorder)
> > - load a midi file into rosegarden
> > - midi file plays successfully
> > - close rosegarden
> > at this point one of the threads of rosegarden fails to
> exit and stays
> > forever in the process list, in a ps axuw it shows as:
> >
> > nando 5484 0.0 0.0 0 0 pts/1 D 13:32 0:00
> [rosegardenseque]
> >
> > Anything else that I try to stop that touches the alsa
> sequencer never
> > dies (qjackctl, vkeybd, qsynth, etc). Anything I try to
> start that tries
> > to use it does not start. This happened with two widely
> different
>
> could you get a tasklist-dump? It's either SysRq-T, or:
>
> echo t > /proc/sysrq-trigger
>
> that should dump all tasks and their backtraces -
> including the hung
> rosegardensequencer task.
>
I had similar symptoms here (FC4) and cured them with
attached patch against linux/2.6.15/rt18/kernel/softirq.c.
Its in rt19 and ++ i think.

Karsten






___________________________________________________________
Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de--- /tmp/softirq.c~ 2006-02-28 20:17:03.000000000 +0100
+++ /tmp/softirq.c 2006-02-28 20:17:03.000000000 +0100
@@ -351,13 +351,13 @@
static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec) = { NULL };

static void inline
-__tasklet_common_schedule(struct tasklet_struct *t, struct tasklet_head *head)
+__tasklet_common_schedule(struct tasklet_struct *t, struct tasklet_head *head, unsigned int nr)
{
if (tasklet_trylock(t)) {
WARN_ON(t->next != NULL);
t->next = head->list;
head->list = t;
- raise_softirq_irqoff(TASKLET_SOFTIRQ);
+ raise_softirq_irqoff(nr);
tasklet_unlock(t);
}
}
@@ -367,7 +367,7 @@
unsigned long flags;

raw_local_irq_save(flags);
- __tasklet_common_schedule(t, &__get_cpu_var(tasklet_vec));
+ __tasklet_common_schedule(t, &__get_cpu_var(tasklet_vec), TASKLET_SOFTIRQ);
raw_local_irq_restore(flags);
}

@@ -378,7 +378,7 @@
unsigned long flags;

raw_local_irq_save(flags);
- __tasklet_common_schedule(t, &__get_cpu_var(tasklet_hi_vec));
+ __tasklet_common_schedule(t, &__get_cpu_var(tasklet_hi_vec), HI_SOFTIRQ);
raw_local_irq_restore(flags);
}