[XEN RFC PATCH 13/40] xen/arm: introduce numa_set_node for Arm

[Wei Chen <wei.chen@xxxxxxx>]

This API is used to set one CPU to a NUMA node. If the system
configure NUMA off or system initialize NUMA failed, the
online NUMA node would set to only node#0. This will be done
in following patches. When NUMA turn off or init failed,
node_online_map will be cleared and set node#0 online. So we
use node_online_map to prevent to set a CPU to an offline node.

Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
---
 xen/arch/arm/Makefile      |  1 +
 xen/arch/arm/numa.c        | 31 +++++++++++++++++++++++++++++++
 xen/include/asm-arm/numa.h |  2 ++
 xen/include/asm-x86/numa.h |  1 -
 xen/include/xen/numa.h     |  1 +
 5 files changed, 35 insertions(+), 1 deletion(-)
 create mode 100644 xen/arch/arm/numa.c

diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index 3d3b97b5b4..6e3fb8033e 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o
 obj-y += mem_access.o
 obj-y += mm.o
 obj-y += monitor.o
+obj-$(CONFIG_NUMA) += numa.o
 obj-y += p2m.o
 obj-y += percpu.o
 obj-y += platform.o
diff --git a/xen/arch/arm/numa.c b/xen/arch/arm/numa.c
new file mode 100644
index 0000000000..1e30c5bb13
--- /dev/null
+++ b/xen/arch/arm/numa.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Arm Architecture support layer for NUMA.
+ *
+ * Copyright (C) 2021 Arm Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <xen/init.h>
+#include <xen/nodemask.h>
+#include <xen/numa.h>
+
+void numa_set_node(int cpu, nodeid_t nid)
+{
+    if ( nid >= MAX_NUMNODES ||
+        !nodemask_test(nid, &node_online_map) )
+        nid = 0;
+
+    cpu_to_node[cpu] = nid;
+}
diff --git a/xen/include/asm-arm/numa.h b/xen/include/asm-arm/numa.h
index ab9c4a2448..1162c702df 100644
--- a/xen/include/asm-arm/numa.h
+++ b/xen/include/asm-arm/numa.h
@@ -27,6 +27,8 @@ extern mfn_t first_valid_mfn;
 #define node_start_pfn(nid) (mfn_x(first_valid_mfn))
 #define __node_distance(a, b) (20)
 
+#define numa_set_node(x, y) do { } while (0)
+
 #endif
 
 #endif /* __ARCH_ARM_NUMA_H */
diff --git a/xen/include/asm-x86/numa.h b/xen/include/asm-x86/numa.h
index f8e4e15586..69859b0a57 100644
--- a/xen/include/asm-x86/numa.h
+++ b/xen/include/asm-x86/numa.h
@@ -22,7 +22,6 @@ extern nodeid_t pxm_to_node(unsigned int pxm);
 #define ZONE_ALIGN (1UL << (MAX_ORDER+PAGE_SHIFT))
 
 extern int srat_disabled(void);
-extern void numa_set_node(int cpu, nodeid_t node);
 extern nodeid_t setup_node(unsigned int pxm);
 extern void srat_detect_node(int cpu);
 
diff --git a/xen/include/xen/numa.h b/xen/include/xen/numa.h
index 258a5cb3db..3972aa6b93 100644
--- a/xen/include/xen/numa.h
+++ b/xen/include/xen/numa.h
@@ -70,6 +70,7 @@ extern int valid_numa_range(u64 start, u64 end, nodeid_t 
node);
 
 extern void numa_init_array(void);
 extern void numa_initmem_init(unsigned long start_pfn, unsigned long end_pfn);
+extern void numa_set_node(int cpu, nodeid_t node);
 extern bool numa_off;
 extern int numa_fake;
 
-- 
2.25.1