mm/page_alloc: simplify page_is_buddy() for better code readability (fe925c0c) · Commits · 戴 / test

Simplify page_is_buddy() to reduce the redundant code for better code readability. Signed-off-by:

mm/page_alloc.c

+13 −20

Original line number	Diff line number	Diff line
		@@ -792,32 +792,25 @@ static inline void set_page_order(struct page *page, unsigned int order)
		*
		* For recording page's order, we use page_private(page).
		*/
		static inline int page_is_buddy(struct page page, struct page buddy,
		static inline bool page_is_buddy(struct page page, struct page buddy,
		unsigned int order)
		{
		if (page_is_guard(buddy) && page_order(buddy) == order) {
		if (page_zone_id(page) != page_zone_id(buddy))
		return 0;

		VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
		if (!page_is_guard(buddy) && !PageBuddy(buddy))
		return false;

		return 1;
		}
		if (page_order(buddy) != order)
		return false;

		if (PageBuddy(buddy) && page_order(buddy) == order) {
		/*
		* zone check is done late to avoid uselessly
		* calculating zone/node ids for pages that could
		* never merge.
		* zone check is done late to avoid uselessly calculating
		* zone/node ids for pages that could never merge.
		*/
		if (page_zone_id(page) != page_zone_id(buddy))
		return 0;
		return false;

		VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);

		return 1;
		}
		return 0;
		return true;
		}

		#ifdef CONFIG_COMPACTION