Re: [Xen-devel] [PATCH] x86/xen: Use DIV_ROUND_UP

From: Juergen Gross
Date: Wed Jun 29 2016 - 11:37:22 EST


On 29/06/16 17:34, Jan Beulich wrote:
>>>> On 29.06.16 at 17:00, <amitoj1606@xxxxxxxxx> wrote:
>> --- a/arch/x86/xen/enlighten.c
>> +++ b/arch/x86/xen/enlighten.c
>> @@ -591,7 +591,7 @@ static void xen_load_gdt(const struct desc_ptr *dtr)
>> {
>> unsigned long va = dtr->address;
>> unsigned int size = dtr->size + 1;
>> - unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
>> + unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
>> unsigned long frames[pages];
>> int f;
>>
>> @@ -640,7 +640,7 @@ static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
>> {
>> unsigned long va = dtr->address;
>> unsigned int size = dtr->size + 1;
>> - unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
>> + unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
>> unsigned long frames[pages];
>> int f;
>>
>
> Perhaps even more readable would be PFN_DOWN()?

Or PFN_UP() to be correct?


Juergen