Re: [PATCH 1/9] MIPS: Support hard limit of cpu count (nr_cpu_ids)

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 04-04-2014 12:11, Huacai Chen wrote:

> On MIPS currently, only the soft limit of cpu count (maxcpus) has its
> effect, this patch enable the hard limit (nr_cpus) as well. Processor
> cores which greater than maxcpus and less than nr_cpus can be taken up
> via cpu hotplug. The code is borrowed from X86.

> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> ---
>   arch/mips/kernel/setup.c |   18 ++++++++++++++++++
>   1 files changed, 18 insertions(+), 0 deletions(-)

> diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
> index a842154..7ffda01 100644
> --- a/arch/mips/kernel/setup.c
> +++ b/arch/mips/kernel/setup.c
> @@ -729,6 +729,23 @@ static void __init resource_init(void)
>   	}
>   }
>
> +static void __init prefill_possible_map(void)
> +{
> +#ifdef CONFIG_SMP
> +	int i, possible = num_possible_cpus();
> +
> +	if (possible > nr_cpu_ids)
> +		possible = nr_cpu_ids;
> +
> +	for (i = 0; i < possible; i++)
> +		set_cpu_possible(i, true);
> +	for (; i < NR_CPUS; i++)
> +		set_cpu_possible(i, false);
> +
> +	nr_cpu_ids = possible;
> +#endif
 > +}
 > +

    #ifdef's in the function body are ugly. Instead I'm suggesting:

#ifdef CONFIG_SMP
static void __init prefill_possible_map(void)
{
[...]
}
#else
static inline void prefill_possible_map(void) {}
#endif

WBR, Sergei