ANDROID: page_pinner: add missing page_pinner_put_page

aosp/2369528 missed page_pinner_put_page in put_page_testzero
path. Fix it.

Bug: 274967172
Bug: 240196534
Change-Id: Ia2af2ffb752f8405b4289ca88cde09f201548e1f
Signed-off-by: Minchan Kim <minchan@google.com>
(cherry picked from commit 2488e2e472e7f66933b1f190251a35f13ea67699)
Signed-off-by: Georgi Djakov <quic_c_gdjako@quicinc.com>

include/linux/mm.h

@@ -29,6 +29,7 @@
 #include <linux/sched.h>
 #include <linux/pgtable.h>
 #include <linux/kasan.h>
+#include <linux/page_pinner.h>
 #include <linux/memremap.h>
 #include <linux/slab.h>
 #include <linux/rcuwait.h>
@@ -1231,8 +1232,13 @@ static inline unsigned int folio_order(const struct folio *folio)
  */
 static inline int put_page_testzero(struct page *page)
 {
+	int ret;
+
 	VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
-	return page_ref_dec_and_test(page);
+	ret = page_ref_dec_and_test(page);
+	page_pinner_put_page(page);
+
+	return ret;
 }
 
 static inline int folio_put_testzero(struct folio *folio)

include/linux/page_pinner.h

@@ -24,9 +24,6 @@ static inline void page_pinner_put_page(struct page *page)
 	if (!static_branch_unlikely(&page_pinner_inited))
 		return;
 
-	if (!static_branch_unlikely(&failure_tracking))
-		return;
-
 	__page_pinner_put_page(page);
 }
 
@@ -35,9 +32,6 @@ static inline void page_pinner_failure_detect(struct page *page)
 	if (!static_branch_unlikely(&page_pinner_inited))
 		return;
 
-	if (!static_branch_unlikely(&failure_tracking))
-		return;
-
 	__page_pinner_failure_detect(page);
 }
 #else

mm/page_pinner.c

@@ -57,9 +57,9 @@ static struct page_pinner_buffer pp_buffer;
 
 static bool page_pinner_enabled;
 DEFINE_STATIC_KEY_FALSE(page_pinner_inited);
+EXPORT_SYMBOL_GPL(page_pinner_inited);
 
 DEFINE_STATIC_KEY_TRUE(failure_tracking);
-EXPORT_SYMBOL_GPL(failure_tracking);
 
 static depot_stack_handle_t failure_handle;
 
@@ -255,11 +255,15 @@ err:
 
 void __page_pinner_failure_detect(struct page *page)
 {
-	struct page_ext *page_ext = page_ext_get(page);
+	struct page_ext *page_ext;
 	struct page_pinner *page_pinner;
 	struct captured_pinner record;
 	u64 now;
 
+	if (!static_branch_unlikely(&failure_tracking))
+		return;
+
+	page_ext = page_ext_get(page);
 	if (unlikely(!page_ext))
 		return;
 
@@ -285,11 +289,15 @@ EXPORT_SYMBOL_GPL(__page_pinner_failure_detect);
 
 void __page_pinner_put_page(struct page *page)
 {
-	struct page_ext *page_ext = page_ext_get(page);
+	struct page_ext *page_ext;
 	struct page_pinner *page_pinner;
 	struct captured_pinner record;
 	u64 now, ts_usec;
 
+	if (!static_branch_unlikely(&failure_tracking))
+		return;
+
+	page_ext = page_ext_get(page);
 	if (unlikely(!page_ext))
 		return;