mm/debug: dump compound page information on a second line

Simplify both the implementation and the output by splitting all the
compound page information onto a second line.
Reported-by: NJohn Hubbard <jhubbard@nvidia.com>
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Tested-by: NJohn Hubbard <jhubbard@nvidia.com>
Reviewed-by: NJohn Hubbard <jhubbard@nvidia.com>
Acked-by: NMike Rapoport <rppt@linux.ibm.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: William Kucharski <william.kucharski@oracle.com>
Link: http://lkml.kernel.org/r/20200709202117.7216-3-willy@infradead.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/debug.c

@@ -95,27 +95,21 @@ void __dump_page(struct page *page, const char *reason)
 	 */
 	mapcount = PageSlab(head) ? 0 : page_mapcount(page);
 
-	if (compound)
+	pr_warn("page:%px refcount:%d mapcount:%d mapping:%p index:%#lx\n",
+			page, page_ref_count(head), mapcount, mapping,
+			page_to_pgoff(page));
+	if (compound) {
 		if (hpage_pincount_available(page)) {
-			pr_warn("page:%px refcount:%d mapcount:%d mapping:%p "
-				"index:%#lx head:%px order:%u "
-				"compound_mapcount:%d compound_pincount:%d\n",
-				page, page_ref_count(head), mapcount,
-				mapping, page_to_pgoff(page), head,
-				compound_order(head), compound_mapcount(page),
-				compound_pincount(page));
+			pr_warn("head:%px order:%u compound_mapcount:%d compound_pincount:%d\n",
+					head, compound_order(head),
+					compound_mapcount(head),
+					compound_pincount(head));
 		} else {
-			pr_warn("page:%px refcount:%d mapcount:%d mapping:%p "
-				"index:%#lx head:%px order:%u "
-				"compound_mapcount:%d\n",
-				page, page_ref_count(head), mapcount,
-				mapping, page_to_pgoff(page), head,
-				compound_order(head), compound_mapcount(page));
+			pr_warn("head:%px order:%u compound_mapcount:%d\n",
+					head, compound_order(head),
+					compound_mapcount(head));
 		}
-	else
-		pr_warn("page:%px refcount:%d mapcount:%d mapping:%p index:%#lx\n",
-			page, page_ref_count(page), mapcount,
-			mapping, page_to_pgoff(page));
+	}
 	if (PageKsm(page))
 		type = "ksm ";
 	else if (PageAnon(page))