Messages in this thread | | | From | "Matthias Urlichs" <> | Date | Mon, 28 Jun 2004 03:24:07 +0200 | Subject | Re: [parisc-linux] Re: [PATCH] Fix the cpumask rewrite |
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Hi,
Chris Wedgwood: > On Sun, Jun 27, 2004 at 02:00:03PM +0200, Matthias Urlichs wrote: > > > <heretic> > > #define jiffies __get_jiffies() > > </heretic> > > Well, I have that but it's only part of the story. > True.
> As Alan pointed out a suitable API could also make it easier to work > towards a clock-less system for embedded targets. > Well, drivers do need some way of timing things, else they wouldn't read jiffies in the first place. So, at minimum, an embedded system would need a way to trigger a timeout at some specified time in the future.
A simple __get_jiffies() implementation could just set up a 1/HZ-second timer (and busy-wait for it, and increase its internal jiffies counter) every tenth call or so. That would probably slow down the whole system somewhat, but I'd assume it'd mostly work.
-- Matthias Urlichs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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