Context switching

Joel Sherrill joel.sherrill at OARcorp.com
Thu Mar 2 04:01:15 UTC 2000


Is the task both preemptible and timesliced?  Both must be enabled
for timeslicing to work.

FYI dispatching is done at the end of the outermost interrupt.  

> "Jimen.Ching" wrote:
> 
> Hi all,
> 
> I have a question about context switching.  I'm looking through the
> code
> and see that a context switch may be attempted in rtems_clock_tick if
> dispatching is enabled.  But rtems_clock_tick is called from inside an
> 
> interrupt handler.  Thus, _Thread_Dispatch_disable_level is always
> greater
> than zero, and the context switch is never done.
> 
> Did I miss something?  I'm trying to use timeslicing, 100 ticks per
> slice,
> but it doesn't seem to work.
> 
> Thanks in advance for any help.
> 
> --jc
> --
> jimen at adtech-inc.com     Adtech, Inc.    (808) 734-3300

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
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