[PATCH 9/9] mm/page_alloc: Update PGFREE outside the zone lock in __free_pages_ok

From: Mel Gorman
Date: Thu Apr 22 2021 - 07:16:39 EST


VM events do not need explicit protection by disabling IRQs so
update the counter with IRQs enabled in __free_pages_ok.

Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
---
mm/page_alloc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6dd2ea78eddb..9959dc4d7764 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1557,13 +1557,14 @@ static void __free_pages_ok(struct page *page, unsigned int order,
migratetype = get_pfnblock_migratetype(page, pfn);

spin_lock_irqsave(&zone->lock, flags);
- __count_vm_events(PGFREE, 1 << order);
if (unlikely(has_isolate_pageblock(zone) ||
is_migrate_isolate(migratetype))) {
migratetype = get_pfnblock_migratetype(page, pfn);
}
__free_one_page(page, pfn, zone, order, migratetype, fpi_flags);
spin_unlock_irqrestore(&zone->lock, flags);
+
+ __count_vm_events(PGFREE, 1 << order);
}

void __free_pages_core(struct page *page, unsigned int order)
--
2.26.2