mm: remove the total_mapcount argument from page_trans_huge_mapcount()

All callers pass NULL, so we can stop calculating the value we would
store in it.

Link: https://lkml.kernel.org/r/20211220205943.456187-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 4d7245e..cef65f9 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -799,19 +799,15 @@ static inline int page_mapcount(struct page *page)
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 int total_mapcount(struct page *page);
-int page_trans_huge_mapcount(struct page *page, int *total_mapcount);
+int page_trans_huge_mapcount(struct page *page);
 #else
 static inline int total_mapcount(struct page *page)
 {
        return page_mapcount(page);
 }
-static inline int page_trans_huge_mapcount(struct page *page,
-                                          int *total_mapcount)
+static inline int page_trans_huge_mapcount(struct page *page)
 {
-       int mapcount = page_mapcount(page);
-       if (total_mapcount)
-               *total_mapcount = mapcount;
-       return mapcount;
+       return page_mapcount(page);
 }
 #endif
 

diff --git a/include/linux/swap.h b/include/linux/swap.h
index bdccbf1..1d38d94 100644 (file)
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -681,7 +681,7 @@ static inline int swp_swapcount(swp_entry_t entry)
 }
 
 #define reuse_swap_page(page) \
-       (page_trans_huge_mapcount(page, NULL) == 1)
+       (page_trans_huge_mapcount(page) == 1)
 
 static inline int try_to_free_swap(struct page *page)
 {

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b61fbe9..6ed86a8 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2542,38 +2542,28 @@ int total_mapcount(struct page *page)
  * need full accuracy to avoid breaking page pinning, because
  * page_trans_huge_mapcount() is slower than page_mapcount().
  */
-int page_trans_huge_mapcount(struct page *page, int *total_mapcount)
+int page_trans_huge_mapcount(struct page *page)
 {
-       int i, ret, _total_mapcount, mapcount;
+       int i, ret;
 
        /* hugetlbfs shouldn't call it */
        VM_BUG_ON_PAGE(PageHuge(page), page);
 
-       if (likely(!PageTransCompound(page))) {
-               mapcount = atomic_read(&page->_mapcount) + 1;
-               if (total_mapcount)
-                       *total_mapcount = mapcount;
-               return mapcount;
-       }
+       if (likely(!PageTransCompound(page)))
+               return atomic_read(&page->_mapcount) + 1;
 
        page = compound_head(page);
 
-       _total_mapcount = ret = 0;
+       ret = 0;
        for (i = 0; i < thp_nr_pages(page); i++) {
-               mapcount = atomic_read(&page[i]._mapcount) + 1;
+               int mapcount = atomic_read(&page[i]._mapcount) + 1;
                ret = max(ret, mapcount);
-               _total_mapcount += mapcount;
        }
-       if (PageDoubleMap(page)) {
+
+       if (PageDoubleMap(page))
                ret -= 1;
-               _total_mapcount -= thp_nr_pages(page);
-       }
-       mapcount = compound_mapcount(page);
-       ret += mapcount;
-       _total_mapcount += mapcount;
-       if (total_mapcount)
-               *total_mapcount = _total_mapcount;
-       return ret;
+
+       return ret + compound_mapcount(page);
 }
 
 /* Racy check whether the huge page can be split */

diff --git a/mm/swapfile.c b/mm/swapfile.c
index a93f5b5..caa9f81 100644 (file)
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1619,7 +1619,7 @@ static int page_trans_huge_map_swapcount(struct page *page,
                        swapcount = page_swapcount(page);
                if (total_swapcount)
                        *total_swapcount = swapcount;
-               return swapcount + page_trans_huge_mapcount(page, NULL);
+               return swapcount + page_trans_huge_mapcount(page);
        }
 
        page = compound_head(page);