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Date: Fri, 14 May 2004 09:51:40 +1000
From: Nick Piggin <nickpiggin@yahoo.com.au>
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To: Oleg Nesterov <oleg@tv-sign.ru>
CC: linux-kernel@vger.kernel.org, Andrew Morton <akpm@osdl.org>,
       Ingo Molnar <mingo@redhat.com>
Subject: Re: 2.6.6-mm2
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Oleg Nesterov wrote:
> Hello.
> 
> Andrew Morton wrote:
> 
>>+yield_irq.patch
>>
>>From: Nick Piggin
>>
>>this_rq_lock does a local_irq_disable, and sched_yield()
>>needs to undo that.
> 
> 
> I beleive it is safe to enter schedule() with interrupts
> disabled. schedule() does spin_lock_irq()->local_irq_disable()
> anyway.
> 
> Could you please explain, why it is needed?
> 

It is safe to enter schedule() with interrupts disabled. I
found this "problem" while searching for something else in
sched.c

For consistency it is a good thing to do, however I would
be just as happy with a 1 line comment instead. Ingo what
do you prefer?