Re: [RFC V1 01/31] mm/debug_vm_pgtable: Directly use vm_get_page_prot()

[Anshuman Khandual]

On 1/26/22 12:45 PM, Christoph Hellwig wrote:
>> +	 *
>> +	 * Protection based vm_flags combinatins are always linear
>> +	 * and increasing i.e VM_NONE ..[VM_SHARED|READ|WRITE|EXEC].
>>  	 */
>> -	for (idx = 0; idx < ARRAY_SIZE(protection_map); idx++) {
>> +	for (i = VM_NONE; i <= (VM_SHARED | VM_READ | VM_WRITE | VM_EXEC); ix++) {
>>  		pte_basic_tests(&args, idx);
>>  		pmd_basic_tests(&args, idx);
>>  		pud_basic_tests(&args, idx);
> 
> This looks rather convoluted.  I'd prefer to add a helper for the body
> of this loop, and then explicitly call it for all the valid
> combinations.  Right now all are valid, so this dosn't change a thing
> except for generating larger code due to the explicit loop unrolling,
> but I think it is much easier to follow and maintain.

IIUC, then will just keep this unchanged.