Re: [PATCH 2/3] mm/vmstat: simplify the array size calculation

[Miaohe Lin]

On 2021/7/16 20:58, David Hildenbrand wrote:
> On 15.07.21 14:29, Miaohe Lin wrote:
>> We can replace the array_num * sizeof(array[0]) with sizeof(array) to
>> simplify the code.
> 
> Could have mentioned taht your fixing indentation of one "return true;"
> 

Yes, but I thought that's too trivial to mention... I would pay attention to it later.

> LGTM
> 
> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

Many thanks for your review and reply!

> 
>>
>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>> ---
>>   mm/vmstat.c | 8 +++-----
>>   1 file changed, 3 insertions(+), 5 deletions(-)
>>
>> diff --git a/mm/vmstat.c b/mm/vmstat.c
>> index 57e8e7fda7aa..76aef9510f6d 100644
>> --- a/mm/vmstat.c
>> +++ b/mm/vmstat.c
>> @@ -1889,17 +1889,15 @@ static bool need_update(int cpu)
>>           /*
>>            * The fast way of checking if there are any vmstat diffs.
>>            */
>> -        if (memchr_inv(pzstats->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS *
>> -                   sizeof(pzstats->vm_stat_diff[0])))
>> +        if (memchr_inv(pzstats->vm_stat_diff, 0, sizeof(pzstats->vm_stat_diff)))
>>               return true;
>>             if (last_pgdat == zone->zone_pgdat)
>>               continue;
>>           last_pgdat = zone->zone_pgdat;
>>           n = per_cpu_ptr(zone->zone_pgdat->per_cpu_nodestats, cpu);
>> -        if (memchr_inv(n->vm_node_stat_diff, 0, NR_VM_NODE_STAT_ITEMS *
>> -                   sizeof(n->vm_node_stat_diff[0])))
>> -            return true;
>> +        if (memchr_inv(n->vm_node_stat_diff, 0, sizeof(n->vm_node_stat_diff)))
>> +            return true;
>>       }
>>       return false;
>>   }
>>
> 
>