mm-wrap-__find_buddy_pfn-with-a-necessary-buddy-page-validation-v4

updates per David

Link: https://lkml.kernel.org/r/20220401230804.1658207-2-zi.yan@sent.com
Link: https://lore.kernel.org/linux-mm/CAHk-=3Dwji_AmYygZMTsPMdJ7XksMt7kOur8oDfDdniBRMjm4VkQ@mail.gmail.com/
Link: https://lkml.kernel.org/r/7236E7CA-B5F1-4C04-AB85-E86FA3E9A54B@nvidia.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/internal.h b/mm/internal.h
index 56bbae014e0e640d8f14832bc8ff576ffc34e595..6ec89b4f0bc877a0bbbfbc9bbd3abb70fb39f33f 100644 (file)
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -252,7 +252,7 @@ static inline unsigned int buddy_order(struct page *page)
  * For recording page's order, we use page_private(page).
  */
 static inline bool page_is_buddy(struct page *page, struct page *buddy,
-                                                       unsigned int order)
+                                unsigned int order)
 {
        if (!page_is_guard(buddy) && !PageBuddy(buddy))
                return false;
@@ -312,8 +312,8 @@ __find_buddy_pfn(unsigned long page_pfn, unsigned int order)
 static inline struct page *find_buddy_page_pfn(struct page *page,
                        unsigned long pfn, unsigned int order, unsigned long *buddy_pfn)
 {
-       struct page *buddy;
        unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order);
+       struct page *buddy;
 
        buddy = page + (__buddy_pfn - pfn);
        if (buddy_pfn)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c6a18aabe30e87490d736cb0a22351d7213d546d..60d3009e914922fb234ee3ff7242bc4e928c2133 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -976,8 +976,8 @@ static inline bool
 buddy_merge_likely(unsigned long pfn, unsigned long buddy_pfn,
                   struct page *page, unsigned int order)
 {
-       struct page *higher_page;
        unsigned long higher_page_pfn;
+       struct page *higher_page;
 
        if (order >= MAX_ORDER - 2)
                return false;