Re: [External] Re: [PATCH v5 13/21] mm/hugetlb: Use PG_slab to indicate split pmd

2020-11-23 Thread Muchun Song
On Mon, Nov 23, 2020 at 3:48 PM Michal Hocko wrote: > > On Fri 20-11-20 17:30:27, Muchun Song wrote: > > On Fri, Nov 20, 2020 at 4:16 PM Michal Hocko wrote: > > > > > > On Fri 20-11-20 14:43:17, Muchun Song wrote: > > > > When we allocate hugetlb page from buddy, we may need split huge pmd > > >

Re: [External] Re: [PATCH v5 13/21] mm/hugetlb: Use PG_slab to indicate split pmd

2020-11-22 Thread Michal Hocko
On Fri 20-11-20 17:30:27, Muchun Song wrote: > On Fri, Nov 20, 2020 at 4:16 PM Michal Hocko wrote: > > > > On Fri 20-11-20 14:43:17, Muchun Song wrote: > > > When we allocate hugetlb page from buddy, we may need split huge pmd > > > to pte. When we free the hugetlb page, we can merge pte to pmd.

Re: [External] Re: [PATCH v5 13/21] mm/hugetlb: Use PG_slab to indicate split pmd

2020-11-20 Thread Muchun Song
On Fri, Nov 20, 2020 at 4:16 PM Michal Hocko wrote: > > On Fri 20-11-20 14:43:17, Muchun Song wrote: > > When we allocate hugetlb page from buddy, we may need split huge pmd > > to pte. When we free the hugetlb page, we can merge pte to pmd. So > > we need to distinguish whether the previous pmd

Re: [PATCH v5 13/21] mm/hugetlb: Use PG_slab to indicate split pmd

2020-11-20 Thread Michal Hocko
On Fri 20-11-20 14:43:17, Muchun Song wrote: > When we allocate hugetlb page from buddy, we may need split huge pmd > to pte. When we free the hugetlb page, we can merge pte to pmd. So > we need to distinguish whether the previous pmd has been split. The > page table is not allocated from slab. So

[PATCH v5 13/21] mm/hugetlb: Use PG_slab to indicate split pmd

2020-11-19 Thread Muchun Song
When we allocate hugetlb page from buddy, we may need split huge pmd to pte. When we free the hugetlb page, we can merge pte to pmd. So we need to distinguish whether the previous pmd has been split. The page table is not allocated from slab. So we can reuse the PG_slab to indicate that the pmd