[PATCH mm-unstable v5 05/10] mm/hugetlb: convert update_and_free_page() to folios

Sidhartha Kumar
2022-11-29T22:51:48Z

Make more progress on converting the free_huge_page() destructor to
operate on folios by converting update_and_free_page() to folios.

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
---
mm/hugetlb.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 90ba01a76f87..83777d1ccbf3 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1478,7 +1478,7 @@ static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio,
* apply.
*
* This handles the case where more than one ref is held when and
- * after update_and_free_page is called.
+ * after update_and_free_hugetlb_folio is called.
*
* In the case of demote we do not ref count the page as it will soon
* be turned into a page of smaller size.
@@ -1609,7 +1609,7 @@ static void __update_and_free_page(struct hstate *h, struct page *page)
}

/*
- * As update_and_free_page() can be called under any context, so we cannot
+ * As update_and_free_hugetlb_folio() can be called under any context, so we cannot
* use GFP_KERNEL to allocate vmemmap pages. However, we can defer the
* actual freeing in a workqueue to prevent from using GFP_ATOMIC to allocate
* the vmemmap pages.
@@ -1657,11 +1657,11 @@ static inline void flush_free_hpage_work(struct hstate *h)
flush_work(&free_hpage_work);
}

-static void update_and_free_page(struct hstate *h, struct page *page,
+static void update_and_free_hugetlb_folio(struct hstate *h, struct folio *folio,
bool atomic)
{
- if (!HPageVmemmapOptimized(page) || !atomic) {
- __update_and_free_page(h, page);
+ if (!folio_test_hugetlb_vmemmap_optimized(folio) || !atomic) {
+ __update_and_free_page(h, &folio->page);
return;
}

@@ -1672,16 +1672,18 @@ static void update_and_free_page(struct hstate *h, struct page *page,
* empty. Otherwise, schedule_work() had been called but the workfn
* hasn't retrieved the list yet.
*/
- if (llist_add((struct llist_node *)&page->mapping, &hpage_freelist))
+ if (llist_add((struct llist_node *)&folio->mapping, &hpage_freelist))
schedule_work(&free_hpage_work);
}

static void update_and_free_pages_bulk(struct hstate *h, struct list_head *list)
{
struct page *page, *t_page;
+ struct folio *folio;

list_for_each_entry_safe(page, t_page, list, lru) {
- update_and_free_page(h, page, false);
+ folio = page_folio(page);
+ update_and_free_hugetlb_folio(h, folio, false);
cond_resched();
}
}
@@ -1751,12 +1753,12 @@ void free_huge_page(struct page *page)
if (folio_test_hugetlb_temporary(folio)) {
remove_hugetlb_folio(h, folio, false);
spin_unlock_irqrestore(&hugetlb_lock, flags);
- update_and_free_page(h, page, true);
+ update_and_free_hugetlb_folio(h, folio, true);
} else if (h->surplus_huge_pages_node[nid]) {
/* remove the page from active list */
remove_hugetlb_folio(h, folio, true);
spin_unlock_irqrestore(&hugetlb_lock, flags);
- update_and_free_page(h, page, true);
+ update_and_free_hugetlb_folio(h, folio, true);
} else {
arch_clear_hugepage_flags(page);
enqueue_huge_page(h, page);
@@ -2172,8 +2174,8 @@ int dissolve_free_huge_page(struct page *page)
spin_unlock_irq(&hugetlb_lock);

/*
- * Normally update_and_free_page will allocate required vmemmmap
- * before freeing the page. update_and_free_page will fail to
+ * Normally update_and_free_hugtlb_folio will allocate required vmemmmap
+ * before freeing the page. update_and_free_hugtlb_folio will fail to
* free the page if it can not allocate required vmemmap. We
* need to adjust max_huge_pages if the page is not freed.
* Attempt to allocate vmemmmap here so that we can take
@@ -2181,7 +2183,7 @@ int dissolve_free_huge_page(struct page *page)
*/
rc = hugetlb_vmemmap_restore(h, &folio->page);
if (!rc) {
- update_and_free_page(h, &folio->page, false);
+ update_and_free_hugetlb_folio(h, folio, false);
} else {
spin_lock_irq(&hugetlb_lock);
add_hugetlb_page(h, &folio->page, false);
@@ -2818,7 +2820,7 @@ static int alloc_and_dissolve_huge_page(struct hstate *h, struct page *old_page,
* Pages have been replaced, we can safely free the old one.
*/
spin_unlock_irq(&hugetlb_lock);
- update_and_free_page(h, old_page, false);
+ update_and_free_hugetlb_folio(h, old_folio, false);
}

return ret;
@@ -2827,7 +2829,7 @@ static int alloc_and_dissolve_huge_page(struct hstate *h, struct page *old_page,
spin_unlock_irq(&hugetlb_lock);
/* Page has a zero ref count, but needs a ref to be freed */
folio_ref_unfreeze(new_folio, 1);
- update_and_free_page(h, new_page, false);
+ update_and_free_hugetlb_folio(h, new_folio, false);

return ret;
}
--
2.38.1