Re: [v1 PATCH 4/4] RISC-V: Support nr_cpus command line option.

From: Damien Le Moal
Date: Tue Mar 19 2019 - 19:58:19 EST


On 2019/03/20 8:56, Damien Le Moal wrote:
> On 2019/03/20 7:20, Atish Patra wrote:
>> If nr_cpus command line option is set, maximum possible cpu should be
>> set to that value.
>>
>> Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
>> ---
>> arch/riscv/kernel/smpboot.c | 10 +++++++++-
>> 1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
>> index 609475c5..a8fe590c 100644
>> --- a/arch/riscv/kernel/smpboot.c
>> +++ b/arch/riscv/kernel/smpboot.c
>> @@ -86,11 +86,19 @@ void __init setup_smp(void)
>> }
>>
>> cpuid_to_hartid_map(cpuid) = hart;
>> - set_cpu_possible(cpuid, true);
>
> This looks weird: the code being changed does not match what patch 3/4 did.

Arg... Ignore this one. My bad. Morning here, I need more coffee :)

>
>> cpuid++;
>> }
>>
>> BUG_ON(!found_boot_cpu);
>> +
>> + if (cpuid > nr_cpu_ids)
>> + pr_warn("Total number of cpus [%d] are greater than configured via nr_cpus [%d]\n",
>
> "The total number of cpus [%d] is greater than nr_cpus option value [%d]\n"
>
>> + cpuid, nr_cpu_ids);
>> +
>> + for (cpuid = 1; cpuid < nr_cpu_ids; cpuid++) {
>> + if (cpuid_to_hartid_map(cpuid) != INVALID_HARTID)
>> + set_cpu_possible(cpuid, true);
>> + }
>> }
>>
>> int __cpu_up(unsigned int cpu, struct task_struct *tidle)
>>
>
>


--
Damien Le Moal
Western Digital Research