mm: print out memmap number only if it is not zero

Don't print the size of the zone's memmap array if it does not have one.

Impact: cleanup

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d8ac01474563..2f644c3e3da3 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3469,9 +3469,10 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
                         PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
                 if (realsize >= memmap_pages) {
                         realsize -= memmap_pages;
-                        printk(KERN_DEBUG
-                                "  %s zone: %lu pages used for memmap\n",
-                                zone_names[j], memmap_pages);
+                        if (memmap_pages)
+                                printk(KERN_DEBUG
+                                       "  %s zone: %lu pages used for memmap\n",
+                                       zone_names[j], memmap_pages);
                 } else
                         printk(KERN_WARNING
                                 "  %s zone: %lu pages exceeds realsize %lu\n",