[PATCH v2 4/6] mm/hugetlb: rename folio_putback_active_hugetlb() to folio_putback_hugetlb()

David Hildenbrand
2025-01-13T13:16:54Z

Now that folio_putback_hugetlb() is only called on folios that were
previously isolated through folio_isolate_hugetlb(), let's rename it to
match folio_putback_lru().

Add some kernel doc to clarify how this function is supposed to be used.

Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
include/linux/hugetlb.h | 4 ++--
mm/hugetlb.c | 15 +++++++++++++--
mm/migrate.c | 6 +++---
3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index c95ad5cd7894d..ec8c0ccc8f959 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -157,7 +157,7 @@ bool folio_isolate_hugetlb(struct folio *folio, struct list_head *list);
int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison);
int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared);
-void folio_putback_active_hugetlb(struct folio *folio);
+void folio_putback_hugetlb(struct folio *folio);
void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason);
void hugetlb_fix_reserve_counts(struct inode *inode);
extern struct mutex *hugetlb_fault_mutex_table;
@@ -430,7 +430,7 @@ static inline int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
return 0;
}

-static inline void folio_putback_active_hugetlb(struct folio *folio)
+static inline void folio_putback_hugetlb(struct folio *folio)
{
}

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 95579bd8c4fe0..bc4ab45d9b93b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7430,7 +7430,7 @@ __weak unsigned long hugetlb_mask_last_page(struct hstate *h)
* it is already isolated/non-migratable.
*
* On success, an additional folio reference is taken that must be dropped
- * using folio_putback_active_hugetlb() to undo the isolation.
+ * using folio_putback_hugetlb() to undo the isolation.
*
* Return: True if isolation worked, otherwise False.
*/
@@ -7482,7 +7482,18 @@ int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
return ret;
}

-void folio_putback_active_hugetlb(struct folio *folio)
+/**
+ * folio_putback_hugetlb - unisolate a hugetlb folio
+ * @folio: the isolated hugetlb folio
+ *
+ * Putback/un-isolate the hugetlb folio that was previous isolated using
+ * folio_isolate_hugetlb(): marking it non-isolated/migratable and putting it
+ * back onto the active list.
+ *
+ * Will drop the additional folio reference obtained through
+ * folio_isolate_hugetlb().
+ */
+void folio_putback_hugetlb(struct folio *folio)
{
spin_lock_irq(&hugetlb_lock);
folio_set_hugetlb_migratable(folio);
diff --git a/mm/migrate.c b/mm/migrate.c
index 7e23e78f1e57b..be9e3b48cd622 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -137,7 +137,7 @@ void putback_movable_pages(struct list_head *l)

list_for_each_entry_safe(folio, folio2, l, lru) {
if (unlikely(folio_test_hugetlb(folio))) {
- folio_putback_active_hugetlb(folio);
+ folio_putback_hugetlb(folio);
continue;
}
list_del(&folio->lru);
@@ -1454,7 +1454,7 @@ static int unmap_and_move_huge_page(new_folio_t get_new_folio,

if (folio_ref_count(src) == 1) {
/* page was freed from under us. So we are done. */
- folio_putback_active_hugetlb(src);
+ folio_putback_hugetlb(src);
return MIGRATEPAGE_SUCCESS;
}

@@ -1537,7 +1537,7 @@ static int unmap_and_move_huge_page(new_folio_t get_new_folio,
folio_unlock(src);
out:
if (rc == MIGRATEPAGE_SUCCESS)
- folio_putback_active_hugetlb(src);
+ folio_putback_hugetlb(src);
else if (rc != -EAGAIN)
list_move_tail(&src->lru, ret);

--
2.47.1