[PATCH v2 4/4] iop: implement sched_clock()
Aaro Koskinen
aaro.koskinen at nokia.com
Tue Sep 29 03:08:21 EDT 2009
Hello,
Mikael Pettersson wrote:
> This adds a better sched_clock() to the IOP platform,
> implemented using its new clocksource support.
>
> Tested on n2100, compile-tested for all plat-iop machines.
>
> Signed-off-by: Mikael Pettersson <mikpe at it.uu.se>
> ---
> Changes v1 -> v2:
> * implemented sched_clock()
>
> arch/arm/plat-iop/time.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff -rupN linux-2.6.31.arm-iop-3-generictime-v2/arch/arm/plat-iop/time.c linux-2.6.31.arm-iop-4-sched_clock/arch/arm/plat-iop/time.c
> --- linux-2.6.31.arm-iop-3-generictime-v2/arch/arm/plat-iop/time.c 2009-09-26 17:25:09.000000000 +0200
> +++ linux-2.6.31.arm-iop-4-sched_clock/arch/arm/plat-iop/time.c 2009-09-26 17:24:29.000000000 +0200
> @@ -66,6 +66,14 @@ static void __init iop_clocksource_set_h
> }
>
> /*
> + * IOP sched_clock() implementation via its clocksource.
> + */
> +unsigned long long sched_clock(void)
> +{
> + return cyc2ns(&iop_clocksource, iop_clocksource_read(NULL));
> +}
> +
> +/*
This may not work properly on 2.6.31 because the multiplier may be adjusted. If you want
to run these patches on top of 2.6.31, check the OMAP sched_clock() which uses mult_orig,
or maybe drop this patch.
You could also rebase onto current mainline, and use clocksource_cyc2ns().
See commits 80ea3bac3a47bc73efa334d0dd57099d0ff14216 and
0a54419836254a27baecd9037103171bcbabaf67 for more info.
A.
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