[RFC 28/41] hw/core/slot: Maintain the core queue in CPU slot

[Zhao Liu <zhao1.liu@xxxxxxxxxxxxxxx>]

From: Zhao Liu <zhao1.liu@xxxxxxxxx>

Maintain the cores queue at cpu-slot to facilitate direct traversal
of all cores.

Signed-off-by: Zhao Liu <zhao1.liu@xxxxxxxxx>
---
 hw/core/cpu-slot.c         | 43 ++++++++++++++++++++++++++++++++++++++
 include/hw/core/cpu-slot.h |  9 ++++++++
 include/hw/cpu/core.h      |  2 ++
 3 files changed, 54 insertions(+)

diff --git a/hw/core/cpu-slot.c b/hw/core/cpu-slot.c
index 5aef5b0189c2..a6b7d98dea18 100644
--- a/hw/core/cpu-slot.c
+++ b/hw/core/cpu-slot.c
@@ -22,6 +22,40 @@
 
 #include "hw/core/cpu-slot.h"
 
+static void cpu_slot_add_topo_info(CPUTopoState *root, CPUTopoState *child)
+{
+    CPUSlot *slot = CPU_SLOT(root);
+    CPUTopoLevel level = CPU_TOPO_LEVEL(child);
+
+    if (level == CPU_TOPO_CORE) {
+        QTAILQ_INSERT_TAIL(&slot->cores, CPU_CORE(child), node);
+    }
+    return;
+}
+
+static void cpu_slot_del_topo_info(CPUTopoState *root, CPUTopoState *child)
+{
+    CPUSlot *slot = CPU_SLOT(root);
+    CPUTopoLevel level = CPU_TOPO_LEVEL(child);
+
+    if (level == CPU_TOPO_CORE) {
+        QTAILQ_REMOVE(&slot->cores, CPU_CORE(child), node);
+    }
+    return;
+}
+
+static void cpu_slot_update_topo_info(CPUTopoState *root, CPUTopoState *child,
+                                      bool is_realize)
+{
+    g_assert(child->parent);
+
+    if (is_realize) {
+        cpu_slot_add_topo_info(root, child);
+    } else {
+        cpu_slot_del_topo_info(root, child);
+    }
+}
+
 static void cpu_slot_class_init(ObjectClass *oc, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(oc);
@@ -31,12 +65,21 @@ static void cpu_slot_class_init(ObjectClass *oc, void *data)
     dc->user_creatable = false;
 
     tc->level = CPU_TOPO_ROOT;
+    tc->update_topo_info = cpu_slot_update_topo_info;
+}
+
+static void cpu_slot_instance_init(Object *obj)
+{
+    CPUSlot *slot = CPU_SLOT(obj);
+
+    QTAILQ_INIT(&slot->cores);
 }
 
 static const TypeInfo cpu_slot_type_info = {
     .name = TYPE_CPU_SLOT,
     .parent = TYPE_CPU_TOPO,
     .class_init = cpu_slot_class_init,
+    .instance_init = cpu_slot_instance_init,
     .instance_size = sizeof(CPUSlot),
 };
 
diff --git a/include/hw/core/cpu-slot.h b/include/hw/core/cpu-slot.h
index 718c8ecaa751..d2a1160562be 100644
--- a/include/hw/core/cpu-slot.h
+++ b/include/hw/core/cpu-slot.h
@@ -22,17 +22,26 @@
 #define CPU_SLOT_H
 
 #include "hw/core/cpu-topo.h"
+#include "hw/cpu/core.h"
 #include "hw/qdev-core.h"
 
 #define TYPE_CPU_SLOT "cpu-slot"
 
 OBJECT_DECLARE_SIMPLE_TYPE(CPUSlot, CPU_SLOT)
 
+/**
+ * CPUSlot:
+ * @cores: Queue consisting of all the cores in the topology tree
+ *     where the cpu-slot is the root. cpu-slot can maintain similar
+ *     queues for other topology levels to facilitate traversal
+ *     when necessary.
+ */
 struct CPUSlot {
     /*< private >*/
     CPUTopoState parent_obj;
 
     /*< public >*/
+    QTAILQ_HEAD(, CPUCore) cores;
 };
 
 #endif /* CPU_SLOT_H */
diff --git a/include/hw/cpu/core.h b/include/hw/cpu/core.h
index 591240861efb..65dc10931190 100644
--- a/include/hw/cpu/core.h
+++ b/include/hw/cpu/core.h
@@ -40,6 +40,8 @@ struct CPUCore {
      * "-device"/"device_add"?
      */
     int plugged_threads;
+
+    QTAILQ_ENTRY(CPUCore) node;
 };
 
 #endif
-- 
2.34.1