We make sure that we cannot have any memory holes right at the beginning
of offline_pages(). We no longer need walk_system_ram_range() and can
call test_pages_isolated() directly.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Yang <redacted>
Cc: Baoquan He <redacted>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: David Hildenbrand <redacted>
---
 mm/memory_hotplug.c | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 6856702af68d9..f64478349148d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c

@@ -1384,17 +1384,6 @@ offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
        return 0;
 }

-/*
- * Check all pages in range, recorded as memory resource, are isolated.
- */
-static int
-check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
-                       void *data)
-{
-       return test_pages_isolated(start_pfn, start_pfn + nr_pages,
-                                  MEMORY_OFFLINE);
-}
-
 static int __init cmdline_parse_movable_node(char *p)
 {
        movable_node_enabled = true;

@@ -1579,10 +1568,7 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages)
                        reason = "failure to dissolve huge pages";
                        goto failed_removal_isolated;
                }
-               /* check again */
-               ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn,
-                                           NULL, check_pages_isolated_cb);
-       } while (ret);
+       } while (test_pages_isolated(start_pfn, end_pfn, MEMORY_OFFLINE));

        /* Ok, all of our target is isolated.
           We cannot do rollback at this point. */
--

2.26.2