memory hotplug: alloc page from other node in memory online

To initialize hotadded node, some pages are allocated.  At that time, the
node hasn't memory, this makes the allocation always fail.  In such case,
let's allocate pages from other nodes.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Yakui Zhao <yakui.zhao@intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 22 insertions, 7 deletions

diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index f22b4ebbd8dc..3d535d594826 100644
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -116,10 +116,16 @@ static int __init_refok init_section_page_cgroup(unsigned long pfn)
                 nid = page_to_nid(pfn_to_page(pfn));
                 table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;
                 VM_BUG_ON(!slab_is_available());
-                base = kmalloc_node(table_size,
+                if (node_state(nid, N_HIGH_MEMORY)) {
+                        base = kmalloc_node(table_size,
                                 GFP_KERNEL | __GFP_NOWARN, nid);
-                if (!base)
-                        base = vmalloc_node(table_size, nid);
+                        if (!base)
+                                base = vmalloc_node(table_size, nid);
+                } else {
+                        base = kmalloc(table_size, GFP_KERNEL | __GFP_NOWARN);
+                        if (!base)
+                                base = vmalloc(table_size);
+                }
         } else {
                 /*
                  * We don't have to allocate page_cgroup again, but
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index a13ea6401ae7..d9714bdcb4a3 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -48,8 +48,14 @@ void * __meminit vmemmap_alloc_block(unsigned long size, int node)
 {
         /* If the main allocator is up use that, fallback to bootmem. */
         if (slab_is_available()) {
-                struct page *page = alloc_pages_node(node,
+                struct page *page;
+
+                if (node_state(node, N_HIGH_MEMORY))
+                        page = alloc_pages_node(node,
                                 GFP_KERNEL | __GFP_ZERO, get_order(size));
+                else
+                        page = alloc_pages(GFP_KERNEL | __GFP_ZERO,
+                                get_order(size));
                 if (page)
                         return page_address(page);
                 return NULL;
diff --git a/mm/sparse.c b/mm/sparse.c
index da432d9f0ae8..6ce4aab69e99 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -62,9 +62,12 @@ static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
         unsigned long array_size = SECTIONS_PER_ROOT *
                                    sizeof(struct mem_section);
 
-        if (slab_is_available())
-                section = kmalloc_node(array_size, GFP_KERNEL, nid);
-        else
+        if (slab_is_available()) {
+                if (node_state(nid, N_HIGH_MEMORY))
+                        section = kmalloc_node(array_size, GFP_KERNEL, nid);
+                else
+                        section = kmalloc(array_size, GFP_KERNEL);
+        } else
                 section = alloc_bootmem_node(NODE_DATA(nid), array_size);
 
         if (section)