hw/mips: Use object_initialize_child for correct reference counting
authorPhilippe Mathieu-Daudé <philmd@redhat.com>
Tue, 7 May 2019 16:34:10 +0000 (18:34 +0200)
committerEduardo Habkost <ehabkost@redhat.com>
Fri, 24 May 2019 18:29:02 +0000 (15:29 -0300)
As explained in commit aff39be0ed97:

  Both functions, object_initialize() and object_property_add_child()
  increase the reference counter of the new object, so one of the
  references has to be dropped afterwards to get the reference
  counting right. Otherwise the child object will not be properly
  cleaned up when the parent gets destroyed.
  Thus let's use now object_initialize_child() instead to get the
  reference counting here right.

This patch was generated using the following Coccinelle script:

 @use_sysbus_init_child_obj_missing_parent@
 expression child_ptr;
 expression child_type;
 expression child_size;
 @@
 -   object_initialize(child_ptr, child_size, child_type);
     ...
 -   qdev_set_parent_bus(DEVICE(child_ptr), sysbus_get_default());
     ...
 ?-  object_unref(OBJECT(child_ptr));
 +   sysbus_init_child_obj(OBJECT(PARENT_OBJ), "CHILD_NAME", child_ptr,
 +                         child_size, child_type);

We let the Malta/Boston machines adopt the CPS child, and similarly
the CPS adopts the ITU/CPC/GIC/GCR children.

While the object_initialize() function doesn't take an
'Error *errp' argument, the object_initialize_child() does.
Since this code is used when a machine is created (and is not
yet running), we deliberately choose to use the &error_abort
argument instead of ignoring errors if an object creation failed.
This choice also matches when using sysbus_init_child_obj(),
since its code is:

  void sysbus_init_child_obj(Object *parent,
                             const char *childname, void *child,
                             size_t childsize, const char *childtype)
  {
      object_initialize_child(parent, childname, child, childsize,
                              childtype, &error_abort, NULL);

      qdev_set_parent_bus(DEVICE(child), sysbus_get_default());
  }

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Inspired-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190507163416.24647-11-philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
hw/mips/boston.c
hw/mips/cps.c
hw/mips/mips_malta.c

index cb3ea85fdc19c961286801aadcb64e3f6087fa9d..1ffccc8da92667d5524dcf57ce234769eccebfd2 100644 (file)
@@ -455,8 +455,8 @@ static void boston_mach_init(MachineState *machine)
 
     is_64b = cpu_supports_isa(machine->cpu_type, ISA_MIPS64);
 
-    object_initialize(&s->cps, sizeof(s->cps), TYPE_MIPS_CPS);
-    qdev_set_parent_bus(DEVICE(&s->cps), sysbus_get_default());
+    sysbus_init_child_obj(OBJECT(machine), "cps", OBJECT(&s->cps),
+                          sizeof(s->cps), TYPE_MIPS_CPS);
     object_property_set_str(OBJECT(&s->cps), machine->cpu_type, "cpu-type",
                             &err);
     object_property_set_int(OBJECT(&s->cps), smp_cpus, "num-vp", &err);
index fc97f59af4cab24c0e317f928a10c8b32f7d1973..649b35a76c5bbdac912ccba096bd4d28e61af31e 100644 (file)
@@ -94,9 +94,8 @@ static void mips_cps_realize(DeviceState *dev, Error **errp)
 
     /* Inter-Thread Communication Unit */
     if (itu_present) {
-        object_initialize(&s->itu, sizeof(s->itu), TYPE_MIPS_ITU);
-        qdev_set_parent_bus(DEVICE(&s->itu), sysbus_get_default());
-
+        sysbus_init_child_obj(OBJECT(dev), "itu", &s->itu, sizeof(s->itu),
+                              TYPE_MIPS_ITU);
         object_property_set_int(OBJECT(&s->itu), 16, "num-fifo", &err);
         object_property_set_int(OBJECT(&s->itu), 16, "num-semaphores", &err);
         object_property_set_bool(OBJECT(&s->itu), saar_present, "saar-present",
@@ -115,9 +114,8 @@ static void mips_cps_realize(DeviceState *dev, Error **errp)
     }
 
     /* Cluster Power Controller */
-    object_initialize(&s->cpc, sizeof(s->cpc), TYPE_MIPS_CPC);
-    qdev_set_parent_bus(DEVICE(&s->cpc), sysbus_get_default());
-
+    sysbus_init_child_obj(OBJECT(dev), "cpc", &s->cpc, sizeof(s->cpc),
+                          TYPE_MIPS_CPC);
     object_property_set_int(OBJECT(&s->cpc), s->num_vp, "num-vp", &err);
     object_property_set_int(OBJECT(&s->cpc), 1, "vp-start-running", &err);
     object_property_set_bool(OBJECT(&s->cpc), true, "realized", &err);
@@ -130,9 +128,8 @@ static void mips_cps_realize(DeviceState *dev, Error **errp)
                             sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->cpc), 0));
 
     /* Global Interrupt Controller */
-    object_initialize(&s->gic, sizeof(s->gic), TYPE_MIPS_GIC);
-    qdev_set_parent_bus(DEVICE(&s->gic), sysbus_get_default());
-
+    sysbus_init_child_obj(OBJECT(dev), "gic", &s->gic, sizeof(s->gic),
+                          TYPE_MIPS_GIC);
     object_property_set_int(OBJECT(&s->gic), s->num_vp, "num-vp", &err);
     object_property_set_int(OBJECT(&s->gic), 128, "num-irq", &err);
     object_property_set_bool(OBJECT(&s->gic), true, "realized", &err);
@@ -147,9 +144,8 @@ static void mips_cps_realize(DeviceState *dev, Error **errp)
     /* Global Configuration Registers */
     gcr_base = env->CP0_CMGCRBase << 4;
 
-    object_initialize(&s->gcr, sizeof(s->gcr), TYPE_MIPS_GCR);
-    qdev_set_parent_bus(DEVICE(&s->gcr), sysbus_get_default());
-
+    sysbus_init_child_obj(OBJECT(dev), "gcr", &s->gcr, sizeof(s->gcr),
+                          TYPE_MIPS_GCR);
     object_property_set_int(OBJECT(&s->gcr), s->num_vp, "num-vp", &err);
     object_property_set_int(OBJECT(&s->gcr), 0x800, "gcr-rev", &err);
     object_property_set_int(OBJECT(&s->gcr), gcr_base, "gcr-base", &err);
index 04f2117d71ee800569d3b2cedd2b1494c9ebc36c..aff8464f2ac063bafe57b44a66b2264ea4cebf01 100644 (file)
@@ -1151,8 +1151,8 @@ static void create_cps(MaltaState *s, const char *cpu_type,
 {
     Error *err = NULL;
 
-    object_initialize(&s->cps, sizeof(s->cps), TYPE_MIPS_CPS);
-    qdev_set_parent_bus(DEVICE(&s->cps), sysbus_get_default());
+    sysbus_init_child_obj(OBJECT(s), "cps", OBJECT(&s->cps), sizeof(s->cps),
+                          TYPE_MIPS_CPS);
     object_property_set_str(OBJECT(&s->cps), cpu_type, "cpu-type", &err);
     object_property_set_int(OBJECT(&s->cps), smp_cpus, "num-vp", &err);
     object_property_set_bool(OBJECT(&s->cps), true, "realized", &err);