On 10/1/26 15:52, Yeoreum Yun wrote:
>> On 9/29/26 12:01, Yeoreum Yun wrote:
>>>
>>> Okay. I'll change like below in next-spin:
>>>
>>> -------&<-------
>>>
>>> @@ -411,57 +400,78 @@ static bool check_huge_type(uint64_t categories, enum
>>> check_huge_type type)
>>> return false;
>>> }
>>>
>>> -static bool __check_pmd_huge(void *addr, size_t len, int nr_hpages,
>>> - uint64_t hpage_size, enum check_huge_type type)
>>> +static bool __check_huge(void *addr, size_t len, int nr_hpages,
>>> + uint64_t hpage_size, enum check_huge_type type)
>>> {
>>> {
>>> - int pagemap_fd;
>>> + bool ret = false;
>>> + int pagemap_fd, kpageflags_fd;
>>> int nr_pmd_mappings = 0;
>>> + uint64_t pmd_pagesize, scan_mapping_size;
>>> uint64_t categories;
>>> + unsigned long pfn;
>>> + bool check_pmd_mapping, allow_nonpresent;
>>> char *start = addr;
>>> char *end = start + len;
>>>
>>> + pmd_pagesize = read_pmd_pagesize();
>>> + if (!pmd_pagesize)
>>> + ksft_exit_fail_msg("reading PMD pagesize failed\n");
>>> +
>>> + check_pmd_mapping = hpage_size == pmd_pagesize;
>>> + scan_mapping_size = (nr_hpages > 0) ? hpage_size : psize();
>>> + /* Some mTHP tests check a partially populated PMD-sized range. */
>>> + allow_nonpresent = (uint64_t)nr_hpages * hpage_size < len;
>>> +
>>> pagemap_fd = open(PAGEMAP_PATH, O_RDONLY);
>>> if (pagemap_fd < 0)
>>> ksft_exit_fail_perror("open pagemap");
>>>
>>> - for (; start < end; start += hpage_size) {
>>> + kpageflags_fd = open(KPAGEFLAGS_PATH, O_RDONLY);
>>> + if (kpageflags_fd < 0)
>>> + ksft_exit_fail_perror("open kpageflags");
>>> +
>>> + for (; start < end; start += scan_mapping_size) {
>>> categories = pagemap_scan_get_categories(pagemap_fd, start);
>>> - if (!(categories & PAGE_IS_HUGE))
>>> + pfn = pagemap_get_pfn(pagemap_fd, start);
>>> + if (pfn == -1UL) {
>>> + if (!allow_nonpresent)
>>> + goto out;
>>> continue;
>>> - if (check_huge_type(categories, type))
>>> + }
>>> + if (!check_huge_type(categories, type))
>>> + goto out;
>>> + }
>>> +
>>> + if (!check_pmd_mapping) {
>>> + ret = check_large_folios(pagemap_fd, kpageflags_fd,
>>> + addr, len, nr_hpages, hpage_size);
>>> + goto out;
>>> + }
>>> +
>>> + for (start = addr; start < end; start += scan_mapping_size) {
>>> + categories = pagemap_scan_get_categories(pagemap_fd, start);
>>> + if (categories & PAGE_IS_HUGE)
>>> nr_pmd_mappings++;
>>> }
>>> - close(pagemap_fd);
>>>
>>> - return nr_hpages == nr_pmd_mappings;
>>> + if (nr_pmd_mappings != nr_hpages)
>>> + goto out;
>>> + ret = true;
>>> +
>>> +out:
>>> + close(pagemap_fd);
>>> + close(kpageflags_fd);
>>> + return ret;
>>> }
>>>
>>
>> I'd leave existing __check_huge() mostly alone, and instead have an
>> additional
>> function that checks the type.
>>
>> Essentially a __check_type() or sth that we run after the large folio / pmd
>> check.
>
> So, You mean like this?
>
> -------&<-------
>
> -enum check_huge_type {
> - CHECK_HUGE_ANON,
> - CHECK_HUGE_FILE,
> +enum check_type {
> + CHECK_TYPE_ANON,
> + CHECK_TYPE_FILE,
> };
>
> -static bool check_huge_type(uint64_t categories, enum check_huge_type type)
> +static bool __check_type(void *addr, size_t len, uint64_t page_size,
> + bool allow_nonpresent, enum check_type type)
As discussed off-list, maybe we can avoid the allow_nonpresent handling!
--
Cheers,
David
