[PATCH v3 8/8] mm: use zone lock guard in __offline_isolated_pages()

[Dmitry Ilvokhin]

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

Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Signed-off-by: Dmitry Ilvokhin <d@xxxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
---
 mm/page_alloc.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 27bd316e4453..8cfec846203f 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7358,7 +7358,7 @@ void zone_pcp_reset(struct zone *zone)
 unsigned long __offline_isolated_pages(unsigned long start_pfn,
 		unsigned long end_pfn)
 {
-	unsigned long already_offline = 0, flags;
+	unsigned long already_offline = 0;
 	unsigned long pfn = start_pfn;
 	struct page *page;
 	struct zone *zone;
@@ -7366,7 +7366,7 @@ unsigned long __offline_isolated_pages(unsigned long start_pfn,
 
 	offline_mem_sections(pfn, end_pfn);
 	zone = page_zone(pfn_to_page(pfn));
-	spin_lock_irqsave(&zone->lock, flags);
+	guard(spinlock_irqsave)(&zone->lock);
 	while (pfn < end_pfn) {
 		page = pfn_to_page(pfn);
 		/*
@@ -7396,7 +7396,6 @@ unsigned long __offline_isolated_pages(unsigned long start_pfn,
 		del_page_from_free_list(page, zone, order, MIGRATE_ISOLATE);
 		pfn += (1 << order);
 	}
-	spin_unlock_irqrestore(&zone->lock, flags);
 
 	return end_pfn - start_pfn - already_offline;
 }
-- 
2.52.0