[PATCH 2/3] mm/page_alloc: remove unnecessary check in break_down_buddy_pages

From: Kemeng Shi
Date: Wed Aug 09 2023 - 21:53:09 EST


1. We always have target in range started with next_page and full free
range started with current_buddy.
2. The last splited range size is 1 << low and low should be >= 0, then
size >= 1, then page + size and page will not interleave.
As summary, current_page will not equal to target page.

Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index fd93d1396ccd..d0b400733031 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6562,10 +6562,8 @@ static void break_down_buddy_pages(struct zone *zone, struct page *page,
if (set_page_guard(zone, current_buddy, high, migratetype))
continue;

- if (current_buddy != target) {
- add_to_free_list(current_buddy, zone, high, migratetype);
- set_buddy_order(current_buddy, high);
- }
+ add_to_free_list(current_buddy, zone, high, migratetype);
+ set_buddy_order(current_buddy, high);
}
}

--
2.30.0