Re: [PATCH 05/19] arm64: smp: Tidy up smp_prepare_cpus()

[Jinjie Ruan <ruanjinjie@huawei.com>]

在 2026/9/8 0:40, Will Deacon 写道:
> smp_prepare_cpus() is always run on the boot CPU (i.e. CPU 0) but goes
> to great lengths to support running on a CPU where smp_processor_id()

Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>

> is non-zero.
> 
> Clean up the code a little by hardcoding zero for the boot CPU ID.
> 
> Signed-off-by: Will Deacon <will@kernel.org>
> ---
>  arch/arm64/kernel/smp.c | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
> index a61dc3016a11..ff045080ca1b 100644
> --- a/arch/arm64/kernel/smp.c
> +++ b/arch/arm64/kernel/smp.c
> @@ -779,16 +779,14 @@ void __init smp_init_cpus(void)
>  void __init smp_prepare_cpus(unsigned int max_cpus)
>  {
>  	const struct cpu_operations *ops;
> -	int err;
>  	unsigned int cpu;
> -	unsigned int this_cpu;
> +	int err;
>  
>  	init_cpu_topology();
>  
> -	this_cpu = smp_processor_id();
> -	store_cpu_topology(this_cpu);
> -	numa_store_cpu_info(this_cpu);
> -	numa_add_cpu(this_cpu);
> +	store_cpu_topology(0);
> +	numa_store_cpu_info(0);
> +	numa_add_cpu(0);
>  
>  	/*
>  	 * If UP is mandated by "nosmp" (which implies "maxcpus=0"), don't set
> @@ -803,8 +801,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
>  	 * secondaries from the bootloader.
>  	 */
>  	for_each_possible_cpu(cpu) {
> -
> -		if (cpu == smp_processor_id())
> +		if (cpu == 0)
>  			continue;
>  
>  		ops = get_cpu_ops(cpu);