Commit 1afec9e8 authored by Markus Armbruster's avatar Markus Armbruster
Browse files

s390x/event-facility: Simplify creation of SCLP event devices 



init_event_facility() creates the SCLP events bus with two SCLP event
devices (sclpquiesce and sclp-cpu-hotplug).  It leaves the devices
unrealized.  A comment explains they will be realized "via the bus".

The bus's realize method sclp_events_bus_realize() indeed realizes all
unrealized devices on this bus.  It carries a TODO comment claiming
this "has to be done in common code".  No other bus realize method
realizes its devices.

The common code in question is bus_set_realized(), which has a TODO
comment asking for recursive realization.  It's been asking for years.

The only devices sclp_events_bus_realize() will ever realize are the
two init_event_facility() puts there.

Simplify as follows:

* Make the devices members of the event facility instance struct, just
  like the bus.  object_initialize_child() is simpler than
  object_property_add_child() and object_unref().

* Realize them in the event facility realize method.

This is in line with how such things are done elsewhere.

Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: qemu-s390x@nongnu.org
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Acked-by: default avatarCornelia Huck <cohuck@redhat.com>
Reviewed-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-54-armbru@redhat.com>
parent e9a82986

hw/s390x/event-facility.c

+29 −35
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ typedef struct SCLPEventsBus { 
struct SCLPEventFacility {

    SysBusDevice parent_obj;

    SCLPEventsBus sbus;

    SCLPEvent quiesce, cpu_hotplug;

    /* guest's receive mask */

    union {

        uint32_t receive_mask_pieces[2];
@@ -328,34 +329,9 @@ static void write_event_mask(SCLPEventFacility *ef, SCCB *sccb) 


#define TYPE_SCLP_EVENTS_BUS "s390-sclp-events-bus"



static void sclp_events_bus_realize(BusState *bus, Error **errp)

{

    Error *err = NULL;

    BusChild *kid;



    /* TODO: recursive realization has to be done in common code */

    QTAILQ_FOREACH(kid, &bus->children, sibling) {

        DeviceState *dev = kid->child;



        object_property_set_bool(OBJECT(dev), true, "realized", &err);

        if (err) {

            error_propagate(errp, err);

            return;

        }

    }

}



static void sclp_events_bus_class_init(ObjectClass *klass, void *data)

{

    BusClass *bc = BUS_CLASS(klass);



    bc->realize = sclp_events_bus_realize;

}



static const TypeInfo sclp_events_bus_info = {

    .name = TYPE_SCLP_EVENTS_BUS,

    .parent = TYPE_BUS,

    .class_init = sclp_events_bus_class_init,

};



static void command_handler(SCLPEventFacility *ef, SCCB *sccb, uint64_t code)
@@ -443,27 +419,44 @@ static void init_event_facility(Object *obj) 
{

    SCLPEventFacility *event_facility = EVENT_FACILITY(obj);

    DeviceState *sdev = DEVICE(obj);

    Object *new;



    event_facility->mask_length = 4;

    event_facility->allow_all_mask_sizes = true;

    object_property_add_bool(obj, "allow_all_mask_sizes",

                             sclp_event_get_allow_all_mask_sizes,

                             sclp_event_set_allow_all_mask_sizes);



    /* Spawn a new bus for SCLP events */

    qbus_create_inplace(&event_facility->sbus, sizeof(event_facility->sbus),

                        TYPE_SCLP_EVENTS_BUS, sdev, NULL);



    new = object_new(TYPE_SCLP_QUIESCE);

    object_property_add_child(obj, TYPE_SCLP_QUIESCE, new);

    object_unref(new);

    qdev_set_parent_bus(DEVICE(new), BUS(&event_facility->sbus));

    object_initialize_child(obj, TYPE_SCLP_QUIESCE,

                            &event_facility->quiesce,

                            TYPE_SCLP_QUIESCE);



    new = object_new(TYPE_SCLP_CPU_HOTPLUG);

    object_property_add_child(obj, TYPE_SCLP_CPU_HOTPLUG, new);

    object_unref(new);

    qdev_set_parent_bus(DEVICE(new), BUS(&event_facility->sbus));

    /* the facility will automatically realize the devices via the bus */

    object_initialize_child(obj, TYPE_SCLP_CPU_HOTPLUG,

                            &event_facility->cpu_hotplug,

                            TYPE_SCLP_CPU_HOTPLUG);

}



static void realize_event_facility(DeviceState *dev, Error **errp)

{

    SCLPEventFacility *event_facility = EVENT_FACILITY(dev);

    Error *local_err = NULL;



    qdev_realize(DEVICE(&event_facility->quiesce),

                 BUS(&event_facility->sbus), &local_err);

    if (local_err) {

        error_propagate(errp, local_err);

        return;

    }

    qdev_realize(DEVICE(&event_facility->cpu_hotplug),

                 BUS(&event_facility->sbus), &local_err);

    if (local_err) {

        error_propagate(errp, local_err);

        qdev_unrealize(DEVICE(&event_facility->quiesce));

        return;

    }

}



static void reset_event_facility(DeviceState *dev)
@@ -479,6 +472,7 @@ static void init_event_facility_class(ObjectClass *klass, void *data) 
    DeviceClass *dc = DEVICE_CLASS(sbdc);

    SCLPEventFacilityClass *k = EVENT_FACILITY_CLASS(dc);



    dc->realize = realize_event_facility;

    dc->reset = reset_event_facility;

    dc->vmsd = &vmstate_event_facility;

    set_bit(DEVICE_CATEGORY_MISC, dc->categories);