minimum stack size was Re: #define delay(...)

[Gerke Kok]

Should not the stacksize be given at the start of the task in the
create_task call? This is used in many systems and is very flexible.
(Althoug I do know it taks more admin. for the kernel)
wkr,
Gerke

-----Oorspronkelijk bericht-----
Van: Joel Sherrill [mailto:joel.sherrill at OARcorp.com]
Verzonden: Friday, November 10, 2000 18:59
Aan: Sergei Organov
CC: rtems-users at OARcorp.com
Onderwerp: minimum stack size was Re: #define delay(...)


Sergei Organov wrote:
> 

> > This name is a relic from the very EARLIEST days of RTEMS.
> 
> "EARLIEST days of RTEMS" recalled me that I've had another suggestion for
> RTEMS. What if in addition to one lower stack size limit
> RTEMS_MINIMUM_STACK_SIZE we introduce another constant,
> let's say, RTEMS_ABSOLUTE_MINIMUM_STACK_SIZE that will be indeed close to
> absolute minimum for given architecture. All the test programs (as well as
> applications) then will continue to use the former constant, but RTEMS
core
> will check input stack size by comparing it to the latter constant.
> 
> The problem with current approach is that the constant is actually too
large
> (e.g., 8K on PowerPC) and as RTEMS core doesn't allow to create tasks with
> smaller stacks, light-weight tasks take too much memory for stack. Using
my
> suggestion ABSOLUTE_MINIMUM will be somewhere around 1K for PowerPC thus
> saving 7K for every light-weight task. Or did situation change in this
area
> since RTEMS-3.6?

Hasn't changed but it has irritated me and I have something in mind.

What about minimum stack size defaulting to the current
RTEMS_MINIMUM_STACK_SIZE
value and the user being able to specify their own default size as an
override.  What do you think of this?

I have also toyed with the idea of moving the fields in CPU table
that are shared by all ports to the regular configuration table.
 
> BR,
> Sergei Organov.

-- 
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