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Date: Mon, 11 Jun 2001 15:45:34 -0700
From: george anzinger <george@mvista.com>
Organization: Monta Vista Software
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To: Jaswinder Singh <jaswinder.singh@3disystems.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: Task Switching in Linux
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Jaswinder Singh wrote:
> 
> In Linux , If we assume that there are only 2 tasks A and B and both are
> equal , this is correct or not :-
> 
> TASK A -> schedule -> switch_to -> TASK B -> schedule -> switch_to ->
> schedule -> switch_to -> TASK A.
> 
Heck no.  TASK A will be run until it either blocks or its time quantum
drops below TASK B's.  It does not matter how many times it calls
schedule(), 'cept its a darn waste of time.

Now, it you call sched_yield() your chances are higher, but still no
guarantee.  If you get the tasks out of SCHED_OTHER sched_yield() will
do the above (if they have the same priority).

George