Re: [Qemu-devel] [PATCH v2 13/16] hw/microblaze/zynqmp: Use object_initialize_child for correct ref. counting
On Tue, May 7, 2019 at 9:46 AM Philippe Mathieu-Daudé wrote:
>
> 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
> (then manually modified to use numbered IPI name)
>
> @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 SoC adopt the IPI 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 _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, _abort, NULL);
>
> qdev_set_parent_bus(DEVICE(child), sysbus_get_default());
> }
>
> Suggested-by: Eduardo Habkost
> Inspired-by: Thomas Huth
> Signed-off-by: Philippe Mathieu-Daudé
Reviewed-by: Alistair Francis
Alistair
> ---
> hw/microblaze/xlnx-zynqmp-pmu.c | 7 ---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/hw/microblaze/xlnx-zynqmp-pmu.c b/hw/microblaze/xlnx-zynqmp-pmu.c
> index 20e973edf5f..0948b1fd5f2 100644
> --- a/hw/microblaze/xlnx-zynqmp-pmu.c
> +++ b/hw/microblaze/xlnx-zynqmp-pmu.c
> @@ -71,9 +71,10 @@ static void xlnx_zynqmp_pmu_soc_init(Object *obj)
>
> /* Create the IPI device */
> for (int i = 0; i < XLNX_ZYNQMP_PMU_NUM_IPIS; i++) {
> -object_initialize(>ipi[i], sizeof(XlnxZynqMPIPI),
> - TYPE_XLNX_ZYNQMP_IPI);
> -qdev_set_parent_bus(DEVICE(>ipi[i]), sysbus_get_default());
> +char *name = g_strdup_printf("ipi%d", i);
> +sysbus_init_child_obj(obj, name, >ipi[i],
> + sizeof(XlnxZynqMPIPI), TYPE_XLNX_ZYNQMP_IPI);
> +g_free(name);
> }
> }
>
> --
> 2.20.1
>
>
Re: [Qemu-devel] [PATCH v2 13/16] hw/microblaze/zynqmp: Use object_initialize_child for correct ref. counting
On 07/05/19 11:34, Philippe Mathieu-Daudé wrote:
> 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
> (then manually modified to use numbered IPI name)
>
> @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 SoC adopt the IPI 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 _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, _abort, NULL);
>
> qdev_set_parent_bus(DEVICE(child), sysbus_get_default());
> }
>
> Suggested-by: Eduardo Habkost
> Inspired-by: Thomas Huth
> Signed-off-by: Philippe Mathieu-Daudé
> ---
> hw/microblaze/xlnx-zynqmp-pmu.c | 7 ---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/hw/microblaze/xlnx-zynqmp-pmu.c b/hw/microblaze/xlnx-zynqmp-pmu.c
> index 20e973edf5f..0948b1fd5f2 100644
> --- a/hw/microblaze/xlnx-zynqmp-pmu.c
> +++ b/hw/microblaze/xlnx-zynqmp-pmu.c
> @@ -71,9 +71,10 @@ static void xlnx_zynqmp_pmu_soc_init(Object *obj)
>
> /* Create the IPI device */
> for (int i = 0; i < XLNX_ZYNQMP_PMU_NUM_IPIS; i++) {
> -object_initialize(>ipi[i], sizeof(XlnxZynqMPIPI),
> - TYPE_XLNX_ZYNQMP_IPI);
> -qdev_set_parent_bus(DEVICE(>ipi[i]), sysbus_get_default());
> +char *name = g_strdup_printf("ipi%d", i);
> +sysbus_init_child_obj(obj, name, >ipi[i],
> + sizeof(XlnxZynqMPIPI), TYPE_XLNX_ZYNQMP_IPI);
> +g_free(name);
> }
> }
>
>
Reviewed-by: Paolo Bonzini
