thp: make split_queue per-node

Andrea Arcangeli suggested to make split queue per-node to improve
scalability.  Let's do it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 63358d9f9aa9..ea2c4d3e0c03 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5210,6 +5210,11 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat)
         pgdat->numabalancing_migrate_nr_pages = 0;
         pgdat->numabalancing_migrate_next_window = jiffies;
 #endif
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+        spin_lock_init(&pgdat->split_queue_lock);
+        INIT_LIST_HEAD(&pgdat->split_queue);
+        pgdat->split_queue_len = 0;
+#endif
         init_waitqueue_head(&pgdat->kswapd_wait);
         init_waitqueue_head(&pgdat->pfmemalloc_wait);
         pgdat_page_ext_init(pgdat);