Re: [patch 02/17] get_cycles() : x86 HAVE_GET_CYCLES

Mathieu Desnoyers
2008-11-13T13:34:59Z

* Geert Uytterhoeven (geert@linux-m68k.org) wrote:
> On Wed, 12 Nov 2008, Mathieu Desnoyers wrote:
> > --- linux.trees.git.orig/arch/x86/include/asm/tsc.h 2008-11-12 18:15:25.000000000 -0500
> > +++ linux.trees.git/arch/x86/include/asm/tsc.h 2008-11-12 18:15:28.000000000 -0500
> > @@ -56,6 +56,18 @@ extern void mark_tsc_unstable(char *reas
> > extern int unsynchronized_tsc(void);
> > int check_tsc_unstable(void);
> >
> > +static inline cycles_t get_cycles_rate(void)
> > +{
> > + if (check_tsc_unstable())
> > + return 0;
> > + return tsc_khz;
> ^^^
>
> The comment in Kconfig says:
>
> | get_cycles_rate() : cycle counter rate, in HZ
> ^^
>
> So what should it be? Hz or kHz?
>

HZ, for consistency.

So it becomes :

+static inline cycles_t get_cycles_rate(void)
+{
+ if (check_tsc_unstable())
+ return 0;
+ return (cycles_t)tsc_khz * 1000;
+}
+

Thanks for spotting this, will be integrated in the next release.

As a side-note, I noticed that I used CLOCK_TICK_RATE on MIPS when I
should use mips_hpt_frequency. This too will be fixed in the next
release.

Mathieu

> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds