[PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[Thomas Huth]

The sclpconsole currently does not have a proper parent in the QOM
tree, so it shows up under /machine/unattached - which is somewhat
ugly. Let's attach it to /machine/sclp instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 include/hw/s390x/sclp.h    |  2 +-
 hw/s390x/s390-virtio-ccw.c | 11 +++++++----
 hw/s390x/sclp.c            |  4 +++-
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
index b405a387b6..abfd6d8868 100644
--- a/include/hw/s390x/sclp.h
+++ b/include/hw/s390x/sclp.h
@@ -222,7 +222,7 @@ static inline int sccb_data_len(SCCB *sccb)
 }
 
 
-void s390_sclp_init(void);
+Object *s390_sclp_init(void);
 void sclp_service_interrupt(uint32_t sccb);
 void raise_irq_cpu_hotplug(void);
 int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code);
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 4dcc213820..e2f9206ded 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -237,11 +237,13 @@ static void s390_create_virtio_net(BusState *bus, const char *name)
     }
 }
 
-static void s390_create_sclpconsole(const char *type, Chardev *chardev)
+static void s390_create_sclpconsole(Object *sclp, const char *type,
+                                    Chardev *chardev)
 {
     DeviceState *dev;
 
     dev = qdev_new(type);
+    object_property_add_child(sclp, type, OBJECT(dev));
     qdev_prop_set_chr(dev, "chardev", chardev);
     qdev_realize_and_unref(dev, sclp_get_event_facility_bus(), &error_fatal);
 }
@@ -252,8 +254,9 @@ static void ccw_init(MachineState *machine)
     int ret;
     VirtualCssBus *css_bus;
     DeviceState *dev;
+    Object *sclp;
 
-    s390_sclp_init();
+    sclp = s390_sclp_init();
     /* init memory + setup max page size. Required for the CPU model */
     s390_memory_init(machine->ram);
 
@@ -302,10 +305,10 @@ static void ccw_init(MachineState *machine)
 
     /* init consoles */
     if (serial_hd(0)) {
-        s390_create_sclpconsole("sclpconsole", serial_hd(0));
+        s390_create_sclpconsole(sclp, "sclpconsole", serial_hd(0));
     }
     if (serial_hd(1)) {
-        s390_create_sclpconsole("sclplmconsole", serial_hd(1));
+        s390_create_sclpconsole(sclp, "sclplmconsole", serial_hd(1));
     }
 
     /* init the TOD clock */
diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index 893e71a41b..75d45fb184 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -379,13 +379,15 @@ void sclp_service_interrupt(uint32_t sccb)
 
 /* qemu object creation and initialization functions */
 
-void s390_sclp_init(void)
+Object *s390_sclp_init(void)
 {
     Object *new = object_new(TYPE_SCLP);
 
     object_property_add_child(qdev_get_machine(), TYPE_SCLP, new);
     object_unref(new);
     qdev_realize(DEVICE(new), NULL, &error_fatal);
+
+    return new;
 }
 
 static void sclp_realize(DeviceState *dev, Error **errp)
-- 
2.44.0

Re: [PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[David Hildenbrand]

On 30.04.24 10:04, Thomas Huth wrote:
> The sclpconsole currently does not have a proper parent in the QOM
> tree, so it shows up under /machine/unattached - which is somewhat
> ugly. Let's attach it to /machine/sclp instead.
> 
> 

IIRC, this should not affect migration

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb

Re: [PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[Thomas Huth]

On 30/04/2024 10.19, David Hildenbrand wrote:
> On 30.04.24 10:04, Thomas Huth wrote:
>> The sclpconsole currently does not have a proper parent in the QOM
>> tree, so it shows up under /machine/unattached - which is somewhat
>> ugly. Let's attach it to /machine/sclp instead.
> 
> IIRC, this should not affect migration


Yes, that's my understanding, too. I also did a quick check from one QEMU 
without this patch to a QEMU that includes this patch, and migration just 
succeeded fine.

> Reviewed-by: David Hildenbrand <david@redhat.com>

Thanks!

  Thomas

Re: [PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[Philippe Mathieu-Daudé]

On 30/4/24 10:22, Thomas Huth wrote:
> On 30/04/2024 10.19, David Hildenbrand wrote:
>> On 30.04.24 10:04, Thomas Huth wrote:
>>> The sclpconsole currently does not have a proper parent in the QOM
>>> tree, so it shows up under /machine/unattached - which is somewhat
>>> ugly. Let's attach it to /machine/sclp instead.
>>
>> IIRC, this should not affect migration
> 
> 
> Yes, that's my understanding, too. I also did a quick check from one 
> QEMU without this patch to a QEMU that includes this patch, and 
> migration just succeeded fine.

Indeed, QOM path isn't used in migration streams.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

> 
>> Reviewed-by: David Hildenbrand <david@redhat.com>
> 
> Thanks!
> 
>   Thomas
> 
> 

Re: [PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[Cédric Le Goater]

On 4/30/24 10:04, Thomas Huth wrote:
> The sclpconsole currently does not have a proper parent in the QOM
> tree, so it shows up under /machine/unattached - which is somewhat
> ugly. Let's attach it to /machine/sclp instead.
> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>   include/hw/s390x/sclp.h    |  2 +-
>   hw/s390x/s390-virtio-ccw.c | 11 +++++++----
>   hw/s390x/sclp.c            |  4 +++-
>   3 files changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
> index b405a387b6..abfd6d8868 100644
> --- a/include/hw/s390x/sclp.h
> +++ b/include/hw/s390x/sclp.h
> @@ -222,7 +222,7 @@ static inline int sccb_data_len(SCCB *sccb)
>   }
>   
>   
> -void s390_sclp_init(void);
> +Object *s390_sclp_init(void);
>   void sclp_service_interrupt(uint32_t sccb);
>   void raise_irq_cpu_hotplug(void);
>   int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code);
> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
> index 4dcc213820..e2f9206ded 100644
> --- a/hw/s390x/s390-virtio-ccw.c
> +++ b/hw/s390x/s390-virtio-ccw.c
> @@ -237,11 +237,13 @@ static void s390_create_virtio_net(BusState *bus, const char *name)
>       }
>   }
>   
> -static void s390_create_sclpconsole(const char *type, Chardev *chardev)
> +static void s390_create_sclpconsole(Object *sclp, const char *type,
> +                                    Chardev *chardev)
>   {
>       DeviceState *dev;
>   
>       dev = qdev_new(type);
> +    object_property_add_child(sclp, type, OBJECT(dev));
>       qdev_prop_set_chr(dev, "chardev", chardev);
>       qdev_realize_and_unref(dev, sclp_get_event_facility_bus(), &error_fatal);
>   }
> @@ -252,8 +254,9 @@ static void ccw_init(MachineState *machine)
>       int ret;
>       VirtualCssBus *css_bus;
>       DeviceState *dev;
> +    Object *sclp;
>   
> -    s390_sclp_init();
> +    sclp = s390_sclp_init();

I would simply drop s390_sclp_init(), same for :

   void s390_init_tod(void);
   void s390_init_ap(void);
   void s390_stattrib_init(void);
   void s390_skeys_init(void);
   void s390_flic_init(void);

These routines all do the same and are not very useful TBH, and I would
add pointers under the s390x MachineState possibly.

Thanks,

C.





>       /* init memory + setup max page size. Required for the CPU model */
>       s390_memory_init(machine->ram);
>   
> @@ -302,10 +305,10 @@ static void ccw_init(MachineState *machine)
>   
>       /* init consoles */
>       if (serial_hd(0)) {
> -        s390_create_sclpconsole("sclpconsole", serial_hd(0));
> +        s390_create_sclpconsole(sclp, "sclpconsole", serial_hd(0));
>       }
>       if (serial_hd(1)) {
> -        s390_create_sclpconsole("sclplmconsole", serial_hd(1));
> +        s390_create_sclpconsole(sclp, "sclplmconsole", serial_hd(1));
>       }
>   
>       /* init the TOD clock */
> diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
> index 893e71a41b..75d45fb184 100644
> --- a/hw/s390x/sclp.c
> +++ b/hw/s390x/sclp.c
> @@ -379,13 +379,15 @@ void sclp_service_interrupt(uint32_t sccb)
>   
>   /* qemu object creation and initialization functions */
>   
> -void s390_sclp_init(void)
> +Object *s390_sclp_init(void)
>   {
>       Object *new = object_new(TYPE_SCLP);
>   
>       object_property_add_child(qdev_get_machine(), TYPE_SCLP, new);
>       object_unref(new);
>       qdev_realize(DEVICE(new), NULL, &error_fatal);
> +
> +    return new;
>   }
>   
>   static void sclp_realize(DeviceState *dev, Error **errp)

Re: [PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[Thomas Huth]

On 30/04/2024 13.58, Cédric Le Goater wrote:
> On 4/30/24 10:04, Thomas Huth wrote:
>> The sclpconsole currently does not have a proper parent in the QOM
>> tree, so it shows up under /machine/unattached - which is somewhat
>> ugly. Let's attach it to /machine/sclp instead.
>>
>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>> ---
>>   include/hw/s390x/sclp.h    |  2 +-
>>   hw/s390x/s390-virtio-ccw.c | 11 +++++++----
>>   hw/s390x/sclp.c            |  4 +++-
>>   3 files changed, 11 insertions(+), 6 deletions(-)
>>
>> diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
>> index b405a387b6..abfd6d8868 100644
>> --- a/include/hw/s390x/sclp.h
>> +++ b/include/hw/s390x/sclp.h
>> @@ -222,7 +222,7 @@ static inline int sccb_data_len(SCCB *sccb)
>>   }
>> -void s390_sclp_init(void);
>> +Object *s390_sclp_init(void);
>>   void sclp_service_interrupt(uint32_t sccb);
>>   void raise_irq_cpu_hotplug(void);
>>   int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code);
>> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
>> index 4dcc213820..e2f9206ded 100644
>> --- a/hw/s390x/s390-virtio-ccw.c
>> +++ b/hw/s390x/s390-virtio-ccw.c
>> @@ -237,11 +237,13 @@ static void s390_create_virtio_net(BusState *bus, 
>> const char *name)
>>       }
>>   }
>> -static void s390_create_sclpconsole(const char *type, Chardev *chardev)
>> +static void s390_create_sclpconsole(Object *sclp, const char *type,
>> +                                    Chardev *chardev)
>>   {
>>       DeviceState *dev;
>>       dev = qdev_new(type);
>> +    object_property_add_child(sclp, type, OBJECT(dev));
>>       qdev_prop_set_chr(dev, "chardev", chardev);
>>       qdev_realize_and_unref(dev, sclp_get_event_facility_bus(), 
>> &error_fatal);
>>   }
>> @@ -252,8 +254,9 @@ static void ccw_init(MachineState *machine)
>>       int ret;
>>       VirtualCssBus *css_bus;
>>       DeviceState *dev;
>> +    Object *sclp;
>> -    s390_sclp_init();
>> +    sclp = s390_sclp_init();
> 
> I would simply drop s390_sclp_init(), same for :
> 
>    void s390_init_tod(void);
>    void s390_init_ap(void);
>    void s390_stattrib_init(void);
>    void s390_skeys_init(void);
>    void s390_flic_init(void);
> 
> These routines all do the same and are not very useful TBH, and I would
> add pointers under the s390x MachineState possibly.

Some of them seem to do a little bit more things, like checking whether the 
feature is available or not, e.g. s390_init_ap() ... IMHO it makes sense to 
keep at least those?

But for s390_sclp_init ... it could be inlined, indeed, especially if we 
also switch the object_unref + qdev_realize in there into 
qdev_realize_and_unref. Let me try to do that in a v2 ...

  Thomas

Re: [PATCH] hw/s390x: Attach the sclpconsole to the /machine/sclp node

[Thomas Huth]

On 30/04/2024 16.24, Thomas Huth wrote:
> On 30/04/2024 13.58, Cédric Le Goater wrote:
>> On 4/30/24 10:04, Thomas Huth wrote:
>>> The sclpconsole currently does not have a proper parent in the QOM
>>> tree, so it shows up under /machine/unattached - which is somewhat
>>> ugly. Let's attach it to /machine/sclp instead.
>>>
>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>> ---
>>>   include/hw/s390x/sclp.h    |  2 +-
>>>   hw/s390x/s390-virtio-ccw.c | 11 +++++++----
>>>   hw/s390x/sclp.c            |  4 +++-
>>>   3 files changed, 11 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
>>> index b405a387b6..abfd6d8868 100644
>>> --- a/include/hw/s390x/sclp.h
>>> +++ b/include/hw/s390x/sclp.h
>>> @@ -222,7 +222,7 @@ static inline int sccb_data_len(SCCB *sccb)
>>>   }
>>> -void s390_sclp_init(void);
>>> +Object *s390_sclp_init(void);
>>>   void sclp_service_interrupt(uint32_t sccb);
>>>   void raise_irq_cpu_hotplug(void);
>>>   int sclp_service_call(S390CPU *cpu, uint64_t sccb, uint32_t code);
>>> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
>>> index 4dcc213820..e2f9206ded 100644
>>> --- a/hw/s390x/s390-virtio-ccw.c
>>> +++ b/hw/s390x/s390-virtio-ccw.c
>>> @@ -237,11 +237,13 @@ static void s390_create_virtio_net(BusState *bus, 
>>> const char *name)
>>>       }
>>>   }
>>> -static void s390_create_sclpconsole(const char *type, Chardev *chardev)
>>> +static void s390_create_sclpconsole(Object *sclp, const char *type,
>>> +                                    Chardev *chardev)
>>>   {
>>>       DeviceState *dev;
>>>       dev = qdev_new(type);
>>> +    object_property_add_child(sclp, type, OBJECT(dev));
>>>       qdev_prop_set_chr(dev, "chardev", chardev);
>>>       qdev_realize_and_unref(dev, sclp_get_event_facility_bus(), 
>>> &error_fatal);
>>>   }
>>> @@ -252,8 +254,9 @@ static void ccw_init(MachineState *machine)
>>>       int ret;
>>>       VirtualCssBus *css_bus;
>>>       DeviceState *dev;
>>> +    Object *sclp;
>>> -    s390_sclp_init();
>>> +    sclp = s390_sclp_init();
>>
>> I would simply drop s390_sclp_init(), same for :
>>
>>    void s390_init_tod(void);
>>    void s390_init_ap(void);
>>    void s390_stattrib_init(void);
>>    void s390_skeys_init(void);
>>    void s390_flic_init(void);
>>
>> These routines all do the same and are not very useful TBH, and I would
>> add pointers under the s390x MachineState possibly.
> 
> Some of them seem to do a little bit more things, like checking whether the 
> feature is available or not, e.g. s390_init_ap() ... IMHO it makes sense to 
> keep at least those?
> 
> But for s390_sclp_init ... it could be inlined, indeed, especially if we 
> also switch the object_unref + qdev_realize in there into 
> qdev_realize_and_unref. Let me try to do that in a v2 ...

Actually, after looking at the code a little bit longer, it seems to me like 
the sclpconsole should be attached to /machine/sclp/s390-sclp-event-facility
instead of just /machine/sclp, since the other devices of type 
TYPE_SCLP_EVENT are also located there. That makes the patch even easier 
since we already have the pointer from sclp_get_event_facility_bus() in that 
function.

  Thomas