[PATCH] powerpc: kernel: remove useless code which related with 'max_cpus'

[Chen Gang]

On 07/22/2013 02:18 PM, Srivatsa S. Bhat wrote:
> On 07/22/2013 11:28 AM, Chen Gang wrote:
>> > Since not need 'max_cpus' after the related commit, the related code
>> > are useless too, need be removed.
>> > 
>> > The related commit:
>> > 
>> >   c1aa687 powerpc: Clean up obsolete code relating to decrementer and timebase
>> > 
>> > The related warning:
>> > 
>> >   arch/powerpc/kernel/smp.c:323:43: warning: parameter �max_cpus� set but not used [-Wunused-but-set-parameter]
>> > 
>> > Signed-off-by: Chen Gang <gang.chen at asianux.com>
>> > ---
>> >  arch/powerpc/kernel/smp.c |    8 --------
>> >  1 files changed, 0 insertions(+), 8 deletions(-)
>> > 
>> > diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
>> > index 38b0ba6..8c2bae4 100644
>> > --- a/arch/powerpc/kernel/smp.c
>> > +++ b/arch/powerpc/kernel/smp.c
>> > @@ -345,14 +345,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
>> > 
>> >  	cpumask_set_cpu(boot_cpuid, cpu_sibling_mask(boot_cpuid));
>> >  	cpumask_set_cpu(boot_cpuid, cpu_core_mask(boot_cpuid));
>> > -
>> > -	if (smp_ops)
>> > -		if (smp_ops->probe)
>> > -			max_cpus = smp_ops->probe();
> No, you can't just remove the call to ->probe(). Its essential.
> For example, one such ->probe() routine, xics_smp_probe() does some
> pretty important stuff, such as populating the ->cause_ipi function
> pointer etc, see below:
> 
> 143 int __init xics_smp_probe(void)
> 144 {
> 145         /* Setup cause_ipi callback  based on which ICP is used */
> 146         smp_ops->cause_ipi = icp_ops->cause_ipi;
> 147 
> 148         /* Register all the IPIs */
> 149         xics_request_ipi();
> 150 
> 151         return cpumask_weight(cpu_possible_mask);
> 152 }
> 

OK, thanks.

>> > -		else
>> > -			max_cpus = NR_CPUS;
>> > -	else
>> > -		max_cpus = 1;
>> >  }
>> >
> Yes, max_cpus is unused, but you have to be careful while removing
> code.

I should send patch v2, soon.  :-)

> Regards,
> Srivatsa S. Bhat
> 
> 
> 

Thanks.
-- 
Chen Gang