[Xenomai-help] Problems with user_irq.c Native example

* [Xenomai-help] Problems with user_irq.c Native example
@ 2010-08-01  7:03 Murilo Marinho
  2010-08-01  9:36 ` Philippe Gerum
  0 siblings, 1 reply; 6+ messages in thread
From: Murilo Marinho @ 2010-08-01  7:03 UTC (permalink / raw)
  To: xenomai

I tried running the user_irq.c example as described in the section
7.14 in the native PDF, which is written in the end of this mail.
At first, it froze my system every time I tried running it. I did some
changes in the code, trying to find out what was wrong with it.

>From what I understood this should work (I'm new to xenomai
programming), the rt_intr_wait function should pause the running task
until the interrupt comes, but after inserting some flow controls, I
found it to be freezing due to excessive processing of the irq_server,
which at first seemed to be receiving endless interruption signals.

In the next step, I added error handling, but the return value of the
function was -38, which didn't mean it worked ( as it wasn't a
positive
value), nor it was any of the errors described in the function documentation.

I also tried changing from TM_INFINITE to many numerical values to no
avail, got the same return value.

Have I misunderstood the way this function works? Does this error
means something?

I'm using ubuntu 9.10, xenomai 2.5.3 and kernel 2.6.34

7.14 user_irq.c
#include <sys/mman.h>
#include <native/task.h>
#include <native/intr.h>
#define IRQ_NUMBER 7 /* Intercept interrupt #7 */
#define TASK_PRIO 99 /* Highest RT priority */
#define TASK_MODE 0 /* No flags */
#define TASK_STKSZ 0 /* Stack size (use default one) */
RT_INTR intr_desc;
RT_TASK server_desc;
void irq_server (void *cookie)
{
for (;;) {
/* Wait for the next interrupt on channel #7. */
err = rt_intr_wait(&intr_desc,TM_INFINITE);
if (!err) {
/* Process interrupt. */
}
}
}
int main (int argc, char *argv[])
{
int err;
mlockall(MCL_CURRENT|MCL_FUTURE);
/* ... */
err = rt_intr_create(&intr_desc,"MyIrq",IRQ_NUMBER,0);
/* ... */
err = rt_task_create(&server_desc,
"MyIrqServer",
TASK_STKSZ,
TASK_PRIO,
TASK_MODE);
if (!err)
rt_task_start(&server_desc,&irq_server,NULL);
/* ... */
}
void cleanup (void)
{
rt_intr_delete(&intr_desc);
rt_task_delete(&server_desc);
}

^ permalink raw reply	[flat|nested] 6+ messages in thread