rtems_task acting strange

[Joel Sherrill]

Salman wrote:
> 
> Hi guys,
> 
> I'm observing strange behavior when executing the following osif_init
> function.
> 
> It gets as far as printing "were gonna startthe task 0 !!!!" (status = 0
> -> successful task creation) and waiting for return key.
> when I press return key, it goes mental, the screen either starts
> dumping infinite garbage, or I get a page of errors with heading related
> to thread error or something (i can't fully read it, cos system reboots
> straight afterwards)
> 
> any idea whats going wrong ?

If osif_init() is an initialization task and an RTEMS Classic API task, 
then it is falling off the bottom and that is a fatal error.  So I think
the system is giving a fatal error.  Try adding an
rtems_task_delete(RTEMS_SELF)
to the bottom instead of a return.

For sure the mq task at the bottom is also falling out the bottom since
you have commented out the infinite task body loop.

> thanks
> 
> Salman
> 
> ----------------- the related functions ------------------
> int osif_init(osif_init_args_t args)
> {
> 
>    rtems_status_code status;
>    rtems_id   Task_id;
> 
>         /* debugging info*/
>         printk ("osif_c #2: were here\n");
>         fflush(stdout);
>         getchar();
> 
>   UnitCount++;
>   if (UnitCount > 1) {
>     return(0);
>   }
> 
>   first_timeout = NULL;
>   main_driver_lock=sem_open("main_driver_lock",O_CREAT,0,1);
>   if (main_driver_lock==(sem_t *) -1)
>     printk("osif_init");
> 
>   Dma_lock=sem_open("Dma_lock",O_CREAT,0,1);
>   if (Dma_lock==(sem_t *) -1)
>     printk("osif_init");
> 
>   FlagInt_lock=sem_open("FlagInt_lock",O_CREAT,0,1);
>   if (FlagInt_lock==(sem_t *) -1)
>     printk("osif_init");
> 
>   AttIndex_lock=sem_open("AttIndex_lock",O_CREAT,0,1);
>   if (AttIndex_lock==(sem_t *) -1)
>     printk("osif_init");
> 
>   time_q_lock=sem_open("time_q_lock",O_CREAT,0,1);
>   if (time_q_lock==(sem_t *) -1)
>     printk("osif_init");
> 
>   to_lock=sem_open("tot_lock",O_CREAT,0,0);
>   if (to_lock==(sem_t *) -1)
>     printk("osif_init");
> 
> /* two tasks start here in vxworks
>  * but are sequentially implemented in linux
>  * fix required
>  * done
>  * one is related to interrupts which we're doing sequentialy in
> sci_interrupthandler, like linux
>  * the other is a task related to timeouts etc, which we implemented as
> rtems_task
>  * taskSpawn("TOT_TASK",2,VX_FP_TASK,40000,(FUNCPTR)
> to_task,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
>  */
> 
>   status = rtems_task_create(
>                   rtems_build_name( 'T', 'S', '0', '1'),
>                   2, RTEMS_MINIMUM_STACK_SIZE * 2, RTEMS_DEFAULT_MODES,
>                   RTEMS_DEFAULT_ATTRIBUTES, &Task_id);
> 
>         /* debugging info*/
>         printf("were gonna startthe task %i !!!!",(int)status);
>         getchar();
>   status = rtems_task_start( Task_id, to_task, 1);
>   return 0;
> }
> 
> rtems_task to_task(rtems_task_argument unused)
> {
>     int gto_data;
>     int retval;
>     struct mq_attr attr;
>    /* commented out for debugging
>     extern void general_timeout_handler( int data);*/
> 
>     attr.mq_flags   = 0;
>     attr.mq_maxmsg  = 128;
>     attr.mq_msgsize = sizeof(int);
> 
>         /* debugging info*/
>     printk("were gonna do the mq_open thing");
>     getchar();
> 
>     mq=mq_open("TOTDATA",O_RDWR|O_CREAT,NULL,&attr);
> 
>         /* debugging info*/
>     printk("just did the mq_open thing");
>     getchar();
>     if (mq== (mqd_t ) -1)
>     {
>         /* debugging info*/
>         printk("mq_open failed\n");
>         getchar();
>         rtems_task_suspend(RTEMS_SELF);
>     }
>         /* debugging info*/
>         printk("mq_open passed\n");
>         getchar();
> /*  commented out for debugging
>     for(;;)
>     {
>         retval=mq_receive(mq,&gto_data,sizeof(int),0);
>         if (retval== -1)
>         {
>                 printk("mq_open failed\n");
>                 rtems_task_suspend(RTEMS_SELF);
>         }
>         general_timeout_handler(gto_data);
>     }
> */
> }

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
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