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RE: Schedule in task_queues works ?



Before calling schedule , state of task should be changed either to
Interruptible or Non interruptible...
  But in my example i am not changing the state ..I think it still is in
  running state....Any way it will be put in ready queue.But i don't 
  know y it not getting chance to run......

On Thu, 25 May 2000, you wrote:
> >   I have one interesting doubt
> > >   Please have a look at small piece of code 
> > > 
> > > void   print()
> > >   {
> > >    printk("The current process %s\n",current->comm);
> > >    schedule();
> > >    printk(" The current process %s\n",current->comm);
> > >   }
> > > 
> > 
> > I'm not sure that you're allowed to use the task queue that way.
> > The purpose of the task queue is what they call "software interrupt
> > handling". When you get a hardware interrupt, you don't want to spend
> > time blocking other irqs, so you queue the work and unmask interrupts.
> > 
> > At other points in time (return from syscall, interrupt, ctx 
> > switch etc), the
> > task queue is checked and executed. I think calling schedule, 
> > when you're
> > in the task queue, will somehow mark the process ineligible 
> > for scheduling.
> 
> Calling schedule will just call the scheduler and maybe some other process
> which is the first in the run queue will get the timeslice.
> You call schedule only when you know that you do not want to use the
> remaining portion of your time slice. Something similar to pthread_yield()
> in the user mode :)
> 
> 
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-- 
*****************************************
Praveen.M
Software Engineer
Emdedded System
Rendezvous On Chip.
Secunderabad.
Email : praveenb@xxxxxxxxx
*****************************************