/proc/pagetypeinfo: fix output for memoryless nodes

on memoryless node, /proc/pagetypeinfo is displayed slightly funny output.
this patch fix it.

output example (header is outputed, but no data is outputed)
--------------------------------------------------------------
Page block order: 14
Pages per block:  16384

Free pages count per migrate type at order       0      1      2      3      4      5    \
  6      7      8      9     10     11     12     13     14     15     16

Number of blocks type     Unmovable  Reclaimable      Movable      Reserve      Isolate
Page block order: 14
Pages per block:  16384

Free pages count per migrate type at order       0      1      2      3      4      5    \
  6      7      8      9     10     11     12     13     14     15     16

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/vmstat.c b/mm/vmstat.c
index ec6035eda933f463ceaa849e8f9f96663a2a025f..280a7ed549f2efc6cf436cc1c2af1b83eb33f439 100644 (file)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -548,6 +548,10 @@ static int pagetypeinfo_show(struct seq_file *m, void *arg)
 {
        pg_data_t *pgdat = (pg_data_t *)arg;
 
+       /* check memoryless node */
+       if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+               return 0;
+
        seq_printf(m, "Page block order: %d\n", pageblock_order);
        seq_printf(m, "Pages per block:  %lu\n", pageblock_nr_pages);
        seq_putc(m, '\n');