Messages in this thread |  | | | From | "Michael S. Zick" <> | | Subject | Re: fishy code in arch/x86/kernel/tsc.c:time_cpufreq_notifier() | | Date | Mon, 1 Jun 2009 16:49:36 -0500 |
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On Mon June 1 2009, Jon Masters wrote: > On Mon, 2009-06-01 at 12:39 -0400, Christoph Hellwig wrote: > > On Mon, Jun 01, 2009 at 12:29:55PM -0400, Dave Jones wrote: > > > diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c > > > index d57de05..78c54ea 100644 > > > --- a/arch/x86/kernel/tsc.c > > > +++ b/arch/x86/kernel/tsc.c > > > @@ -631,17 +631,15 @@ static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, > > > void *data) > > > { > > > struct cpufreq_freqs *freq = data; > > > - unsigned long *lpj, dummy; > > > + unsigned long *lpj; > > > > > > if (cpu_has(&cpu_data(freq->cpu), X86_FEATURE_CONSTANT_TSC)) > > > return 0; > > > > > > - lpj = &dummy; > > > - if (!(freq->flags & CPUFREQ_CONST_LOOPS)) > > > + lpj = &boot_cpu_data.loops_per_jiffy; > > > #ifdef CONFIG_SMP > > > + if (!(freq->flags & CPUFREQ_CONST_LOOPS)) > > > lpj = &cpu_data(freq->cpu).loops_per_jiffy; > > > -#else > > > - lpj = &boot_cpu_data.loops_per_jiffy; > > > #endif > > > > This makes the code look a lot more sane and should fix the potential > > issue. > > Tiny niggle that you wind up setting lpj (loops per jiffy) twice if > you're on SMP and have CPUFREQ_CONST_LOOPS. >
At least it is consistent. ;) You set lpj twice if your not on SMP and have CPUFREG_CONST_LOOPS.
Mike > Jon. > > > -- > 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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