So, we can not simply classify device0 to node0 or node1, but we can
define a node2 which distances to node0 and node1 are the same.

Signed-off-by: Zhen Lei <redacted>
---
 arch/arm64/Kconfig      |  4 ++++
 arch/arm64/kernel/smp.c |  1 +
 arch/arm64/mm/numa.c    | 43 +++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 05c1bf1..5904a62 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig

@@ -581,6 +581,10 @@ config NEED_PER_CPU_EMBED_FIRST_CHUNK
        def_bool y
        depends on NUMA

+config HAVE_MEMORYLESS_NODES
+       def_bool y
+       depends on NUMA
+
 source kernel/Kconfig.preempt
 source kernel/Kconfig.hz

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index d099306..9e15297 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c

@@ -620,6 +620,7 @@ static void __init of_parse_and_init_cpus(void)
                        }

                        bootcpu_valid = true;
+                       early_map_cpu_to_node(0, of_node_to_nid(dn));

                        /*
                         * cpu_logical_map has already been

diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
index df5c842..d73b0a0 100644
--- a/arch/arm64/mm/numa.c
+++ b/arch/arm64/mm/numa.c

@@ -128,6 +128,14 @@ void __init early_map_cpu_to_node(unsigned int cpu, int nid)
                nid = 0;

        cpu_to_node_map[cpu] = nid;
+
+       /*
+        * We should set the numa node of cpu0 as soon as possible, because it
+        * has already been set up online before. cpu_to_node(0) will soon be
+        * called.
+        */
+       if (!cpu)
+               set_cpu_numa_node(cpu, nid);
 }

 #ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA

@@ -215,6 +223,35 @@ int __init numa_add_memblk(int nid, u64 start, u64 end)
        return ret;
 }

+static u64 __init alloc_node_data_from_nearest_node(int nid, const size_t size)
+{
+       int i, best_nid, distance;
+       u64 pa;
+       DECLARE_BITMAP(nodes_map, MAX_NUMNODES);
+
+       bitmap_zero(nodes_map, MAX_NUMNODES);
+       bitmap_set(nodes_map, nid, 1);
+
+find_nearest_node:
+       best_nid = NUMA_NO_NODE;
+       distance = INT_MAX;
+
+       for_each_clear_bit(i, nodes_map, MAX_NUMNODES)
+               if (numa_distance[nid][i] < distance) {
+                       best_nid = i;
+                       distance = numa_distance[nid][i];
+               }
+
+       pa = memblock_alloc_nid(size, SMP_CACHE_BYTES, best_nid);
+       if (!pa) {
+               BUG_ON(best_nid == NUMA_NO_NODE);
+               bitmap_set(nodes_map, best_nid, 1);
+               goto find_nearest_node;
+       }
+
+       return pa;
+}
+
 /**
  * Initialize NODE_DATA for a node on the local memory
  */

@@ -228,7 +265,9 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
        pr_info("Initmem setup node %d [mem %#010Lx-%#010Lx]\n",
                nid, start_pfn << PAGE_SHIFT, (end_pfn << PAGE_SHIFT) - 1);

-       nd_pa = memblock_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
+       nd_pa = memblock_alloc_nid(nd_size, SMP_CACHE_BYTES, nid);
+       if (!nd_pa)
+               nd_pa = alloc_node_data_from_nearest_node(nid, nd_size);
        nd = __va(nd_pa);

        /* report and initialize */

@@ -238,7 +277,7 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
        if (tnid != nid)
                pr_info("    NODE_DATA(%d) on node %d\n", nid, tnid);

-       node_data[nid] = nd;
+       NODE_DATA(nid) = nd;
        memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
        NODE_DATA(nid)->node_id = nid;
        NODE_DATA(nid)->node_start_pfn = start_pfn;
--

2.5.0