[PATCH 5/8] mm: use zone lock guard in take_page_off_buddy()

[Dmitry Ilvokhin]

Use zone_lock_irqsave lock guard in take_page_off_buddy() to replace
the explicit lock/unlock pattern with automatic scope-based cleanup.

This also allows to return directly from the loop, removing the 'ret'
variable.

Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Signed-off-by: Dmitry Ilvokhin <d@xxxxxxxxxxxx>
---
 mm/page_alloc.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2857daf6ebfd..92fa922911d5 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7493,11 +7493,9 @@ bool take_page_off_buddy(struct page *page)
 {
 	struct zone *zone = page_zone(page);
 	unsigned long pfn = page_to_pfn(page);
-	unsigned long flags;
 	unsigned int order;
-	bool ret = false;
 
-	zone_lock_irqsave(zone, flags);
+	guard(zone_lock_irqsave)(zone);
 	for (order = 0; order < NR_PAGE_ORDERS; order++) {
 		struct page *page_head = page - (pfn & ((1 << order) - 1));
 		int page_order = buddy_order(page_head);
@@ -7512,14 +7510,12 @@ bool take_page_off_buddy(struct page *page)
 			break_down_buddy_pages(zone, page_head, page, 0,
 						page_order, migratetype);
 			SetPageHWPoisonTakenOff(page);
-			ret = true;
-			break;
+			return true;
 		}
 		if (page_count(page_head) > 0)
 			break;
 	}
-	zone_unlock_irqrestore(zone, flags);
-	return ret;
+	return false;
 }
 
 /*
-- 
2.47.3