Messages in this thread Patch in this message | | | Date | Fri, 10 Jun 2005 11:15:15 +0200 | From | Pavel Machek <> | Subject | Re: [PATCH] Dynamic tick for x86 version 050602-2 |
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Hi!
> > > +#define NS_TICK_LEN ((1 * 1000000000)/HZ) > > > +#define DYN_TICK_MIN_SKIP 2 > > > + > > > +#ifdef CONFIG_NO_IDLE_HZ > > > + > > > +extern unsigned long dyn_tick_reprogram_timer(void); > > > + > > > +#else > > > + > > > +#define arch_has_safe_halt() 0 > > > +#define dyn_tick_reprogram_timer() {} > > > > do {} while (0) > > > > , else you are preparing trap for someone. > > Can you please explain what the difference between these two are? > Some compiler version specific thing?
It took me quite some remembering. Problem is that with your macros, someone can write
dyn_tick_reprogram_timer() printk();
[notice missing ; at first line], and still get it compile. If you replace {} with do {} while (0), he'll get compile error as he should.
> > > Index: linux-dev/kernel/dyn-tick.c > > > =================================================================== > > > --- /dev/null 1970-01-01 00:00:00.000000000 +0000 > > > +++ linux-dev/kernel/dyn-tick.c 2005-06-02 10:37:12.000000000 -0700 > > > @@ -0,0 +1,235 @@ > > > +/* > > > + * linux/arch/i386/kernel/dyn-tick.c > > > + * > > > + * Beginnings of generic dynamic tick timer support > > > + * > > > + * Copyright (C) 2004 Nokia Corporation > > > + * Written by Tony Lindgen <tony@atomide.com> and > > > + * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com> > > > + * > > Heh, you work for Nokia? Can I get one of those nokia 770 toys? I > > should have 100 euros somewhere here :-). > > Yes, we did dyntick originally for ARM OMAP and 770. I don't think > I have any power who Nokia will be giving the discount developer > 770's for though :) I think you have to apply on some webpage...
Thanks for the info (and for the ARM work). Pavel - 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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