Hi：
On 2021/2/9 8:45, Mike Kravetz wrote:
> On 2/8/21 12:24 AM, Miaohe Lin wrote:
>> We can use helper huge_page_size() to get the hugepage size directly to
>> simplify the code slightly.
>>
>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>> ---
>> mm/hugetlb.c | 14 ++++++--------
>> 1 file changed, 6 insertions(+), 8 deletions(-)
>>
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 18628f8dbfb0..6cdb59d8f663 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -3199,7 +3199,7 @@ void __init hugetlb_add_hstate(unsigned int order)
>> BUG_ON(order == 0);
>> h = &hstates[hugetlb_max_hstate++];
>> h->order = order;
>> - h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1);
>> + h->mask = ~(huge_page_size(h) - 1);
>> for (i = 0; i < MAX_NUMNODES; ++i)
>> INIT_LIST_HEAD(&h->hugepage_freelists[i]);
>> INIT_LIST_HEAD(&h->hugepage_activelist);
>> @@ -3474,7 +3474,7 @@ void hugetlb_report_meminfo(struct seq_file *m)
>> for_each_hstate(h) {
>> unsigned long count = h->nr_huge_pages;
>>
>> - total += (PAGE_SIZE << huge_page_order(h)) * count;
>> + total += huge_page_size(h) * count;
>>
>> if (h == &default_hstate)
>> seq_printf(m,
>> @@ -3487,10 +3487,10 @@ void hugetlb_report_meminfo(struct seq_file *m)
>> h->free_huge_pages,
>> h->resv_huge_pages,
>> h->surplus_huge_pages,
>> - (PAGE_SIZE << huge_page_order(h)) / 1024);
>> + huge_page_size(h) / SZ_1K);
>> }
>>
>> - seq_printf(m, "Hugetlb: %8lu kB\n", total / 1024);
>> + seq_printf(m, "Hugetlb: %8lu kB\n", total / SZ_1K);
>> }
>>
>> int hugetlb_report_node_meminfo(char *buf, int len, int nid)
>> @@ -3524,7 +3524,7 @@ void hugetlb_show_meminfo(void)
>> h->nr_huge_pages_node[nid],
>> h->free_huge_pages_node[nid],
>> h->surplus_huge_pages_node[nid],
>> - 1UL << (huge_page_order(h) + PAGE_SHIFT - 10));
>> + huge_page_size(h) >> 10);
>
> Should we change this to
>
> huge_page_size(h) / SZ_1K);
> > as in hugetlb_report_meminfo above? Or, is that one where it takes an
> additional instruction to do the divide as opposed to the shift? I would> rather add the instruction and keep everything consistent.
>
Yes, it takes an additional instruction to do the divide as opposed to the shift. So I did not
change this. But it seems keeping everything consistent in a function is more important. So should
I send a V2 to change this or Andrew would kindly handle this ?
Many thanks.
