mem-hotplug: alloc new page from a nearest neighbor node when mem-offline
If we offline a node, alloc the new page from a nearest neighbor node
instead of the current node or other remote nodes, because re-migrate is
a waste of time and the distance of the remote nodes is often very
large.
Also use GFP_HIGHUSER_MOVABLE to alloc new page if the zone is movable
zone or highmem zone.
Link: http://lkml.kernel.org/r/5795E18B.5060302@huawei.com
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: David Rientjes <rientjes@google.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 065140e..3894b65 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1548,6 +1548,37 @@
return 0;
}
+static struct page *new_node_page(struct page *page, unsigned long private,
+ int **result)
+{
+ gfp_t gfp_mask = GFP_USER | __GFP_MOVABLE;
+ int nid = page_to_nid(page);
+ nodemask_t nmask = node_online_map;
+ struct page *new_page;
+
+ /*
+ * TODO: allocate a destination hugepage from a nearest neighbor node,
+ * accordance with memory policy of the user process if possible. For
+ * now as a simple work-around, we use the next node for destination.
+ */
+ if (PageHuge(page))
+ return alloc_huge_page_node(page_hstate(compound_head(page)),
+ next_node_in(nid, nmask));
+
+ node_clear(nid, nmask);
+ if (PageHighMem(page)
+ || (zone_idx(page_zone(page)) == ZONE_MOVABLE))
+ gfp_mask |= __GFP_HIGHMEM;
+
+ new_page = __alloc_pages_nodemask(gfp_mask, 0,
+ node_zonelist(nid, gfp_mask), &nmask);
+ if (!new_page)
+ new_page = __alloc_pages(gfp_mask, 0,
+ node_zonelist(nid, gfp_mask));
+
+ return new_page;
+}
+
#define NR_OFFLINE_AT_ONCE_PAGES (256)
static int
do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
@@ -1611,11 +1642,8 @@
goto out;
}
- /*
- * alloc_migrate_target should be improooooved!!
- * migrate_pages returns # of failed pages.
- */
- ret = migrate_pages(&source, alloc_migrate_target, NULL, 0,
+ /* Allocate a new page from the nearest neighbor node */
+ ret = migrate_pages(&source, new_node_page, NULL, 0,
MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
if (ret)
putback_movable_pages(&source);