Re: [PATCH v2 1/2] mm: huge_memory: refactor thpsize_shmem_enabled_store() with sysfs_match_string()

[ranxiaokai627]

>On Wed, May 13, 2026 at 09:45:07AM +0000, ranxiaokai627@xxxxxxx wrote:
>> From: Ran Xiaokai <ran.xiaokai@xxxxxxxxxx>
>>
>> Inspired by commit 82d9ff648c6c ("mm: huge_memory: refactor
>> anon_enabled_store() with set_anon_enabled_mode()"), refactor
>> thpsize_shmem_enabled_store() using sysfs_match_string().
>> This eliminates the duplicated spin_lock/unlock(), set/clear_bit(),
>> calls across all branches, reducing code duplication.
>
>>  static ssize_t thpsize_shmem_enabled_show(struct kobject *kobj,
>>  					  struct kobj_attribute *attr, char *buf)
>>  {
>> @@ -5551,57 +5574,42 @@ static ssize_t thpsize_shmem_enabled_store(struct kobject *kobj,
>>  					   const char *buf, size_t count)
>>  {
>>  	int order = to_thpsize(kobj)->order;
>> +	int mode, m;
>
>I hate single letter variable names (yes I see set_anon_enabled_mode() has it, I
>should have reviewed against that, oops :).
>
>Please give it its type of enum huge_shmem_enalbed_mode.

Hi, Lorenzo,

int main()
{
    enum huge_shmem_enabled_mode mode = 0;
    const char* type_name = _Generic((mode),
        int: "signed int",
        unsigned int: "unsigned int",
        default: "other"
    );
    printf("enum huge_shmem_enabled_mode underlying type is: %s\n", type_name);
    return 0;
}
 ./a.out
enum huge_shmem_enabled_mode underlying type is: unsigned int

This will cause the following check to always evaluate to false and
does not validate input parameters like echo "xxx" > .../hugepages-xxkB/shmem_enable
if (mode < 0)
	return mode;

So i think we should keep mode as integer.

>> +	mode = sysfs_match_string(huge_shmem_enabled_mode_strings, buf);
>> +	if (mode < 0)
>> +		return -EINVAL;