mm/memory hotplug: print the last vmemmap region at the end of hot add memory

When hot add two nodes continuously, we found the vmemmap region info is
a bit messed.  The last region of node 2 is printed when node 3 hot
added, like the following:

  Initmem setup node 2 [mem 0x0000000000000000-0xffffffffffffffff]
   On node 2 totalpages: 0
   Built 2 zonelists in Node order, mobility grouping on.  Total pages: 16090539
   Policy zone: Normal
   init_memory_mapping: [mem 0x40000000000-0x407ffffffff]
    [mem 0x40000000000-0x407ffffffff] page 1G
    [ffffea1000000000-ffffea10001fffff] PMD -> [ffff8a077d800000-ffff8a077d9fffff] on node 2
    [ffffea1000200000-ffffea10003fffff] PMD -> [ffff8a077de00000-ffff8a077dffffff] on node 2
  ...
    [ffffea101f600000-ffffea101f9fffff] PMD -> [ffff8a074ac00000-ffff8a074affffff] on node 2
    [ffffea101fa00000-ffffea101fdfffff] PMD -> [ffff8a074a800000-ffff8a074abfffff] on node 2
  Initmem setup node 3 [mem 0x0000000000000000-0xffffffffffffffff]
   On node 3 totalpages: 0
   Built 3 zonelists in Node order, mobility grouping on.  Total pages: 16090539
   Policy zone: Normal
   init_memory_mapping: [mem 0x60000000000-0x607ffffffff]
    [mem 0x60000000000-0x607ffffffff] page 1G
    [ffffea101fe00000-ffffea101fffffff] PMD -> [ffff8a074a400000-ffff8a074a5fffff] on node 2 <=== node 2 ???
    [ffffea1800000000-ffffea18001fffff] PMD -> [ffff8a074a600000-ffff8a074a7fffff] on node 3
    [ffffea1800200000-ffffea18005fffff] PMD -> [ffff8a074a000000-ffff8a074a3fffff] on node 3
    [ffffea1800600000-ffffea18009fffff] PMD -> [ffff8a0749c00000-ffff8a0749ffffff] on node 3
  ...

The cause is the last region was missed at the and of hot add memory,
and p_start, p_end, node_start were not reset, so when hot add memory to
a new node, it will consider they are not contiguous blocks and print
the previous one.  So we print the last vmemmap region at the end of hot
add memory to avoid the confusion.

Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9e88f749aa512395daea45f2727545fa0f281533..26fbba7d888f887c3383c1bb5829cb4f204e2040 100644 (file)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -513,6 +513,7 @@ int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn,
                        break;
                err = 0;
        }
+       vmemmap_populate_print_last();
 
        return err;
 }