Support MAP_NORESERVE accounting as part of the new counter.
For each hugepage allocation, at allocation time we check if there is a reservation for this allocation or not. If there is a reservation for this allocation, then this allocation was charged at reservation time, and we don't re-account it. If there is no reserevation for this allocation, we charge the appropriate hugetlb_cgroup.
The hugetlb_cgroup to uncharge for this allocation is stored in page[3].private. We use new APIs added in an earlier patch to set this pointer.
--- mm/hugetlb.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index cef15e68626bd..7715018a0af22 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1253,6 +1253,7 @@ static void update_and_free_page(struct hstate *h, struct page *page) 1 << PG_writeback); } VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page, false), page); + VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page, true), page); set_compound_page_dtor(page, NULL_COMPOUND_DTOR); set_page_refcounted(page); if (hstate_is_gigantic(h)) { @@ -1364,6 +1365,9 @@ void free_huge_page(struct page *page) clear_page_huge_active(page); hugetlb_cgroup_uncharge_page(hstate_index(h), pages_per_huge_page(h), page, false); + hugetlb_cgroup_uncharge_page(hstate_index(h), pages_per_huge_page(h), + page, true); + if (restore_reserve) h->resv_huge_pages++;
@@ -1390,6 +1394,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); spin_lock(&hugetlb_lock); set_hugetlb_cgroup(page, NULL, false); + set_hugetlb_cgroup(page, NULL, true); h->nr_huge_pages++; h->nr_huge_pages_node[nid]++; spin_unlock(&hugetlb_lock); @@ -2195,10 +2200,19 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, gbl_chg = 1; }
+ /* If this allocation is not consuming a reservation, charge it now. + */ + if (map_chg || avoid_reserve || !vma_resv_map(vma)) { + ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), + &h_cg, true); + if (ret) + goto out_subpool_put; + } + ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg, false); if (ret) - goto out_subpool_put; + goto out_uncharge_cgroup_reservation;
spin_lock(&hugetlb_lock); /* @@ -2222,6 +2236,11 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, } hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page, false); + if (!vma_resv_map(vma) || map_chg || avoid_reserve) { + hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, + page, true); + } + spin_unlock(&hugetlb_lock);
set_page_private(page, (unsigned long)spool); @@ -2247,6 +2266,10 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, out_uncharge_cgroup: hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg, false); +out_uncharge_cgroup_reservation: + if (map_chg || avoid_reserve || !vma_resv_map(vma)) + hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), + h_cg, true); out_subpool_put: if (map_chg || avoid_reserve) hugepage_subpool_put_pages(spool, 1); -- 2.24.0.rc0.303.g954a862665-goog