From: Arnd Bergmann <arnd@arndb.de>
To: Aubrey <aubreylee@gmail.com>
Subject: Re: [PATCH 1/4] Blackfin: arch patch for 2.6.18
Date: Tue, 26 Sep 2006 11:43:59 +0200
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Cc: "Luke Yang" <luke.adi@gmail.com>, linux-kernel@vger.kernel.org,
       "Andrew Morton" <akpm@osdl.org>
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On Tuesday 26 September 2006 05:42, Aubrey wrote:
> So, in the kernel space, there is always one bit in the IPEND register
> is set. And if there comes a timer interrupt event, in the timer
> interrupt handler, there should be two bits set in the IPEND register.
> Therefore, schedule happens in the return_from_int.
> 
> So, I still say there is no latency here.
> 

Well, if that's true, you should change your idle function not to
explicitly call schedule().

I haven't really understood how you preempt the idle task, but
I guess you can simplify the standard

| while (1) {
|	while (!need_resched())
|		asm("idle");
|	schedule();
| }

to 

| while (1)
| 	asm("idle");


	Arnd <><
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