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Subject: Re: [PATCH 2.6.21-rt2] PowerPC: decrementer clockevent driver
From: Dave Liu <r63238@freescale.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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> > Yes, on some implementations there can be other conditions that
> > make a decrementer exception go away; there is no contradiction
> > here (thankfully).  My wording was sloppy.
> 
> Some CPUs have the DEC exceptions basically edge triggered (yeah I know

for example?

> it sucks). That's why, among others, the IRQ soft-disable code has code
> to re-trigger DEC exceptions ASAP (by setting it to 1.. note that we
> could probably use 0 here, we've been a bit conservative).