[PATCH 1/1] mm/page_ref: introduce page_ref_inc_return

[Christian Borntraeger]

From: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx>

Let's introduce that helper.

Signed-off-by: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
---
 include/linux/page_ref.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
index 8b5e0a9..610e132 100644
--- a/include/linux/page_ref.h
+++ b/include/linux/page_ref.h
@@ -124,6 +124,15 @@ static inline int page_ref_sub_and_test(struct page *page, int nr)
 	return ret;
 }
 
+static inline int page_ref_inc_return(struct page *page)
+{
+	int ret = atomic_inc_return(&page->_refcount);
+
+	if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_and_return))
+		__page_ref_mod_and_return(page, 1, ret);
+	return ret;
+}
+
 static inline int page_ref_dec_and_test(struct page *page)
 {
 	int ret = atomic_dec_and_test(&page->_refcount);
-- 
2.5.5