Commit 58b7f119 authored by Wei Yang's avatar Wei Yang Committed by Linus Torvalds
Browse files

mm/page_alloc.c: extract check_[new|free]_page_bad() common part to page_bad_reason() 



We share similar code in check_[new|free]_page_bad() to get the page's bad
reason.

Let's extract it and reduce code duplication.

Signed-off-by: default avatarWei Yang <richard.weiyang@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Link: http://lkml.kernel.org/r/20200411220357.9636-6-richard.weiyang@gmail.com


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 534fe5e3

mm/page_alloc.c

+17 −19
Original line number Diff line number Diff line
@@ -1070,7 +1070,7 @@ static inline bool page_expected_state(struct page *page, 
	return true;

}



static void check_free_page_bad(struct page *page)

static const char *page_bad_reason(struct page *page, unsigned long flags)

{

	const char *bad_reason = NULL;
@@ -1080,13 +1080,23 @@ static void check_free_page_bad(struct page *page) 
		bad_reason = "non-NULL mapping";

	if (unlikely(page_ref_count(page) != 0))

		bad_reason = "nonzero _refcount";

	if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_FREE))

	if (unlikely(page->flags & flags)) {

		if (flags == PAGE_FLAGS_CHECK_AT_PREP)

			bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag(s) set";

		else

			bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";

	}

#ifdef CONFIG_MEMCG

	if (unlikely(page->mem_cgroup))

		bad_reason = "page still charged to cgroup";

#endif

	bad_page(page, bad_reason);

	return bad_reason;

}



static void check_free_page_bad(struct page *page)

{

	bad_page(page,

		 page_bad_reason(page, PAGE_FLAGS_CHECK_AT_FREE));

}



static inline int check_free_page(struct page *page)
@@ -2083,26 +2093,14 @@ static inline void expand(struct zone *zone, struct page *page, 


static void check_new_page_bad(struct page *page)

{

	const char *bad_reason = NULL;



	if (unlikely(page->flags & __PG_HWPOISON)) {

		/* Don't complain about hwpoisoned pages */

		page_mapcount_reset(page); /* remove PageBuddy */

		return;

	}

	if (unlikely(atomic_read(&page->_mapcount) != -1))

		bad_reason = "nonzero mapcount";

	if (unlikely(page->mapping != NULL))

		bad_reason = "non-NULL mapping";

	if (unlikely(page_ref_count(page) != 0))

		bad_reason = "nonzero _refcount";

	if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP))

		bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set";

#ifdef CONFIG_MEMCG

	if (unlikely(page->mem_cgroup))

		bad_reason = "page still charged to cgroup";

#endif

	bad_page(page, bad_reason);



	bad_page(page,

		 page_bad_reason(page, PAGE_FLAGS_CHECK_AT_PREP));

}



/*