[PATCH mm-unstable v5 09/10] mm/hugetlb: convert hugetlb prep functions to folios

Sidhartha Kumar
2022-11-29T22:52:03Z

Convert prep_new_huge_page() and __prep_compound_gigantic_page() to
folios.

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
---
mm/hugetlb.c | 63 +++++++++++++++++++++++++---------------------------
1 file changed, 30 insertions(+), 33 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5e580ab834c3..f61b4eb58cde 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1789,29 +1789,27 @@ static void __prep_new_hugetlb_folio(struct hstate *h, struct folio *folio)
set_hugetlb_cgroup_rsvd(folio, NULL);
}

-static void prep_new_huge_page(struct hstate *h, struct page *page, int nid)
+static void prep_new_hugetlb_folio(struct hstate *h, struct folio *folio, int nid)
{
- struct folio *folio = page_folio(page);
-
__prep_new_hugetlb_folio(h, folio);
spin_lock_irq(&hugetlb_lock);
__prep_account_new_huge_page(h, nid);
spin_unlock_irq(&hugetlb_lock);
}

-static bool __prep_compound_gigantic_page(struct page *page, unsigned int order,
- bool demote)
+static bool __prep_compound_gigantic_folio(struct folio *folio,
+ unsigned int order, bool demote)
{
int i, j;
int nr_pages = 1 << order;
struct page *p;

- /* we rely on prep_new_huge_page to set the destructor */
- set_compound_order(page, order);
- __ClearPageReserved(page);
- __SetPageHead(page);
+ /* we rely on prep_new_hugetlb_folio to set the destructor */
+ folio_set_compound_order(folio, order);
+ __folio_clear_reserved(folio);
+ __folio_set_head(folio);
for (i = 0; i < nr_pages; i++) {
- p = nth_page(page, i);
+ p = folio_page(folio, i);

/*
* For gigantic hugepages allocated through bootmem at
@@ -1853,43 +1851,41 @@ static bool __prep_compound_gigantic_page(struct page *page, unsigned int order,
VM_BUG_ON_PAGE(page_count(p), p);
}
if (i != 0)
- set_compound_head(p, page);
+ set_compound_head(p, &folio->page);
}
- atomic_set(compound_mapcount_ptr(page), -1);
- atomic_set(subpages_mapcount_ptr(page), 0);
- atomic_set(compound_pincount_ptr(page), 0);
+ atomic_set(folio_mapcount_ptr(folio), -1);
+ atomic_set(folio_subpages_mapcount_ptr(folio), 0);
+ atomic_set(folio_pincount_ptr(folio), 0);
return true;

out_error:
/* undo page modifications made above */
for (j = 0; j < i; j++) {
- p = nth_page(page, j);
+ p = folio_page(folio, j);
if (j != 0)
clear_compound_head(p);
set_page_refcounted(p);
}
/* need to clear PG_reserved on remaining tail pages */
for (; j < nr_pages; j++) {
- p = nth_page(page, j);
+ p = folio_page(folio, j);
__ClearPageReserved(p);
}
- set_compound_order(page, 0);
-#ifdef CONFIG_64BIT
- page[1].compound_nr = 0;
-#endif
- __ClearPageHead(page);
+ folio_set_compound_order(folio, 0);
+ __folio_clear_head(folio);
return false;
}

-static bool prep_compound_gigantic_page(struct page *page, unsigned int order)
+static bool prep_compound_gigantic_folio(struct folio *folio,
+ unsigned int order)
{
- return __prep_compound_gigantic_page(page, order, false);
+ return __prep_compound_gigantic_folio(folio, order, false);
}

-static bool prep_compound_gigantic_page_for_demote(struct page *page,
+static bool prep_compound_gigantic_folio_for_demote(struct folio *folio,
unsigned int order)
{
- return __prep_compound_gigantic_page(page, order, true);
+ return __prep_compound_gigantic_folio(folio, order, true);
}

/*
@@ -2041,7 +2037,7 @@ static struct page *alloc_fresh_huge_page(struct hstate *h,
return NULL;
folio = page_folio(page);
if (hstate_is_gigantic(h)) {
- if (!prep_compound_gigantic_page(page, huge_page_order(h))) {
+ if (!prep_compound_gigantic_folio(folio, huge_page_order(h))) {
/*
* Rare failure to convert pages to compound page.
* Free pages and try again - ONCE!
@@ -2054,7 +2050,7 @@ static struct page *alloc_fresh_huge_page(struct hstate *h,
return NULL;
}
}
- prep_new_huge_page(h, page, page_to_nid(page));
+ prep_new_hugetlb_folio(h, folio, folio_nid(folio));

return page;
}
@@ -3058,10 +3054,10 @@ static void __init gather_bootmem_prealloc(void)
struct hstate *h = m->hstate;

VM_BUG_ON(!hstate_is_gigantic(h));
- WARN_ON(page_count(page) != 1);
- if (prep_compound_gigantic_page(page, huge_page_order(h))) {
- WARN_ON(PageReserved(page));
- prep_new_huge_page(h, page, page_to_nid(page));
+ WARN_ON(folio_ref_count(folio) != 1);
+ if (prep_compound_gigantic_folio(folio, huge_page_order(h))) {
+ WARN_ON(folio_test_reserved(folio));
+ prep_new_hugetlb_folio(h, folio, folio_nid(folio));
free_huge_page(page); /* add to the hugepage allocator */
} else {
/* VERY unlikely inflated ref count on a tail page */
@@ -3480,13 +3476,14 @@ static int demote_free_huge_page(struct hstate *h, struct page *page)
for (i = 0; i < pages_per_huge_page(h);
i += pages_per_huge_page(target_hstate)) {
subpage = nth_page(page, i);
+ folio = page_folio(subpage);
if (hstate_is_gigantic(target_hstate))
- prep_compound_gigantic_page_for_demote(subpage,
+ prep_compound_gigantic_folio_for_demote(folio,
target_hstate->order);
else
prep_compound_page(subpage, target_hstate->order);
set_page_private(subpage, 0);
- prep_new_huge_page(target_hstate, subpage, nid);
+ prep_new_hugetlb_folio(target_hstate, folio, nid);
free_huge_page(subpage);
}
mutex_unlock(&target_hstate->resize_lock);
--
2.38.1