No.of arguments in Task_create task function.

Harikrishna Vuppaladhadiam

Other Parts Discussed in Thread: SYSBIOS

Processor: c6657 Gauss DSP

following is a task create function in vxworks. where there are 10 possible arguments to the task function_fn.

int taskSpawn
    (
    char *  name,             
    int     priority,         
    int     options,       
    int     stackSize,   
    FUNCPTR function_fn,   
    int     arg1,             /* 1st of 10 req'd task args to pass to func */
    int     arg2,
    int     arg3,
    int     arg4,
    int     arg5,
    int     arg6,
    int     arg7,
    int     arg8,
    int     arg9,
    int     arg10
    )

but in Task_create of sysbios I see arg0 and arg1 (2 arguments only). I see elsewhere in the code capability of above number of arguments.

Pl. advise how to accomodate 10 arguments in the task_create().

Regards,

Hari

over 12 years ago

0 Ashish Kapania over 12 years ago

TI__Mastermind 21645 points

Hi Hari,

It is not possible to pass more than 2 arguments to a task. If you do need to pass more arguments, you could put all the arguments in a structure object and pass a pointer to the structure.

Best,

Ashish

0 Harikrishna Vuppaladhadiam over 12 years ago in reply to Ashish Kapania

Expert 1855 points

Hi Ashish,

This is a quick response. Appreciate your help.

I see in sysbios \bios_6_33_06_50\packages\ti\bios\tsk.c:

The implementation is a wrapper function over regular task functions defined. Can we use these functions?

Hari

/*
* ======== dynamicGlue ========
* used to create dynamically created tasks
*/
static Void dynamicGlue(UArg arg0)
{
TSK_Glue *glue = ((TSK_Glue *)arg0);
Fxn fxn = glue->fxn;
Arg *args = glue->args;
Task_Handle tsk;

tsk = Task_self();
tsk->fxn = (ti_sysbios_knl_Task_FuncPtr)fxn;

fxn(args[0], args[1], args[2], args[3], args[4], args[5], args[6], args[7]);
}

/*
* ======== TSK_checkstacks ========
*/
Void TSK_checkstacks(TSK_Handle oldtask, TSK_Handle newtask)
{
Task_checkStacks((Task_Handle)oldtask, (Task_Handle)newtask);
}

/*
* ======== TSK_create ========
*/
TSK_Handle TSK_create(Fxn fxn, TSK_Attrs *attrs, ...)
{
Int i;
va_list arglist;
TSK_Handle task;
TSK_Glue *glue;
Task_Params params;
Error_Block eb;

Task_Params_init(&params);

/* Use segid 0. No alignment needed */
glue = MEM_alloc(0, sizeof(TSK_Glue), 0);

if (glue == NULL) {
return (NULL);
}

if (attrs == NULL) {
attrs = &TSK_ATTRS;
}

params.instance->name = attrs->name;
params.priority = attrs->priority;
params.stack = attrs->stack;
params.stackSize = attrs->stacksize;
params.stackHeap = MEM_getHandle(attrs->stackseg);
params.env = attrs->environ;
params.vitalTaskFlag = attrs->exitflag;

params.arg0 = (UArg)glue;

/*
* Encode arg1 with the fxn for ROV to use prior to task running
*/
params.arg1 = (UArg)fxn;

/* copy args from stack into argument buffer */
va_start(arglist, attrs);
for (i = 0; i < TSK_MAXARGS; i++) {
glue->args[i] = (Arg)va_arg(arglist, UArg);
}
va_end(arglist);

glue->fxn = fxn;
glue->errno = 0;

Error_init(&eb);
task = (TSK_Handle)Task_create((Task_FuncPtr)dynamicGlue, &params, &eb);

if (task == NULL) {
/* Use segid 0 */
MEM_free(0, glue, sizeof(TSK_Glue));
}

return (task);
}

0 Ashish Kapania over 12 years ago in reply to Harikrishna Vuppaladhadiam

TI__Mastermind 21645 points

Hi Hari,

This package (bios_6_33_06_50\packages\ti\bios) contains code to support the legacy DSP/BIOS APIs and we would not recommend using these for SYS/BIOS development. I still think the best way to pass more arguments is to create a structure of 10 arguments and pass a pointer to the structure.

Best,

Ashish

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No.of arguments in Task_create task function.