mm: optimize compound_head() by avoiding a shared page flag
[sfrench/cifs-2.6.git] / mm / page_alloc.c
index fc241fe295abf21a9c015b66a21d0e1eb18ea7d8..36d713e216e8d4dd22d42b3c1f72b570ff0965ea 100644 (file)
@@ -235,12 +235,11 @@ static void prep_compound_page(struct page *page, unsigned long order)
 
        set_compound_page_dtor(page, free_compound_page);
        set_compound_order(page, order);
-       __SetPageCompound(page);
+       __SetPageHead(page);
        for (i = 1; i < nr_pages; i++) {
                struct page *p = page + i;
 
                __SetPageTail(p);
-               __SetPageCompound(p);
                p->first_page = page;
        }
 }
@@ -253,17 +252,16 @@ static void destroy_compound_page(struct page *page, unsigned long order)
        if (unlikely(compound_order(page) != order))
                bad_page(page);
 
-       if (unlikely(!PageCompound(page)))
+       if (unlikely(!PageHead(page)))
                        bad_page(page);
-       __ClearPageCompound(page);
+       __ClearPageHead(page);
        for (i = 1; i < nr_pages; i++) {
                struct page *p = page + i;
 
-               if (unlikely(!PageCompound(p) | !PageTail(p) |
+               if (unlikely(!PageTail(p) |
                                (p->first_page != page)))
                        bad_page(page);
                __ClearPageTail(p);
-               __ClearPageCompound(p);
        }
 }