Re: [Qemu-devel] [PATCH v2 2/4] apic: QOM'ify apic & icc_bus

[Chen Fan <chen.fan.fnst@cn.fujitsu.com>]

On Mon, 2013-11-11 at 11:58 +0800, 赵小强 wrote:
> 于 11/05/2013 04:51 PM, 赵小强 写道:
> > 于 2013年11月05日 16:25, Chen Fan 写道:
> >> On Tue, 2013-11-05 at 15:55 +0800, xiaoqiang zhao wrote:
> >>> changes includes:
> >>> 1. use type constant for apic and kvm_apic
> >>> 2. convert function 'init' to QOM's 'realize' for apic/kvm_apic
> >>> 3. for consistency, also QOM'ify apic's parent bus 'icc_bus'
> >>> ---
> >>>   hw/cpu/icc_bus.c                |   14 ++++++--------
> >>>   hw/i386/kvm/apic.c              |   10 +++++++---
> >>>   hw/intc/apic.c                  |   10 +++++++---
> >>>   hw/intc/apic_common.c           |   13 +++++++------
> >>>   include/hw/cpu/icc_bus.h        |    3 ++-
> >>>   include/hw/i386/apic_internal.h |    5 +++--
> >>>   6 files changed, 32 insertions(+), 23 deletions(-)
> >>>
> >>> diff --git a/hw/cpu/icc_bus.c b/hw/cpu/icc_bus.c
> >>> index 9a4ea7e..1cc64ac 100644
> >>> --- a/hw/cpu/icc_bus.c
> >>> +++ b/hw/cpu/icc_bus.c
> >>> @@ -43,15 +43,13 @@ static const TypeInfo icc_bus_info = {
> >>>     static void icc_device_realize(DeviceState *dev, Error **errp)
> >>>   {
> >>> -    ICCDevice *id = ICC_DEVICE(dev);
> >>> -    ICCDeviceClass *idc = ICC_DEVICE_GET_CLASS(id);
> >>> -
> >>> -    if (idc->init) {
> >>> -        if (idc->init(id) < 0) {
> >>> -            error_setg(errp, "%s initialization failed.",
> >>> -                       object_get_typename(OBJECT(dev)));
> >>> -        }
> >>> +    ICCDeviceClass *idc = ICC_DEVICE_GET_CLASS(dev);
> >>> +
> >>> +    /* convert to QOM */
> >>> +    if (idc->realize) {
> >>> +    idc->realize(dev, errp);
> >>>       }
> >>> +
> >>>   }
> >>>     static void icc_device_class_init(ObjectClass *oc, void *data)
> >>> diff --git a/hw/i386/kvm/apic.c b/hw/i386/kvm/apic.c
> >>> index 84f6056..55f4a53 100644
> >>> --- a/hw/i386/kvm/apic.c
> >>> +++ b/hw/i386/kvm/apic.c
> >>> @@ -13,6 +13,8 @@
> >>>   #include "hw/pci/msi.h"
> >>>   #include "sysemu/kvm.h"
> >>>   +#define TYPE_KVM_APIC "kvm-apic"
> >>> +
> >>>   static inline void kvm_apic_set_reg(struct kvm_lapic_state *kapic,
> >>>                                       int reg_id, uint32_t val)
> >>>   {
> >>> @@ -171,8 +173,10 @@ static const MemoryRegionOps kvm_apic_io_ops = {
> >>>       .endianness = DEVICE_NATIVE_ENDIAN,
> >>>   };
> >>>   -static void kvm_apic_init(APICCommonState *s)
> >>> +static void kvm_apic_realize(DeviceState *dev, Error **errp)
> >>>   {
> >>> +    APICCommonState *s = APIC_COMMON(dev);
> >>> +
> >>>       memory_region_init_io(&s->io_memory, NULL, &kvm_apic_io_ops, 
> >>> s, "kvm-apic-msi",
> >>>                             APIC_SPACE_SIZE);
> >>>   @@ -185,7 +189,7 @@ static void kvm_apic_class_init(ObjectClass 
> >>> *klass, void *data)
> >>>   {
> >>>       APICCommonClass *k = APIC_COMMON_CLASS(klass);
> >>>   -    k->init = kvm_apic_init;
> >>> +    k->realize = kvm_apic_realize;
> >>>       k->set_base = kvm_apic_set_base;
> >>>       k->set_tpr = kvm_apic_set_tpr;
> >>>       k->get_tpr = kvm_apic_get_tpr;
> >>> @@ -195,7 +199,7 @@ static void kvm_apic_class_init(ObjectClass 
> >>> *klass, void *data)
> >>>   }
> >>>     static const TypeInfo kvm_apic_info = {
> >>> -    .name = "kvm-apic",
> >>> +    .name = TYPE_KVM_APIC,
> >>>       .parent = TYPE_APIC_COMMON,
> >>>       .instance_size = sizeof(APICCommonState),
> >>>       .class_init = kvm_apic_class_init,
> >>> diff --git a/hw/intc/apic.c b/hw/intc/apic.c
> >>> index b542628..2d7891d 100644
> >>> --- a/hw/intc/apic.c
> >>> +++ b/hw/intc/apic.c
> >>> @@ -32,6 +32,8 @@
> >>>   #define SYNC_TO_VAPIC                   0x2
> >>>   #define SYNC_ISR_IRR_TO_VAPIC           0x4
> >>>   +#define TYPE_APIC "apic"
> >>> +
> >>>   static APICCommonState *local_apics[MAX_APICS + 1];
> >>>     static void apic_set_irq(APICCommonState *s, int vector_num, int 
> >>> trigger_mode);
> >>> @@ -871,8 +873,10 @@ static const MemoryRegionOps apic_io_ops = {
> >>>       .endianness = DEVICE_NATIVE_ENDIAN,
> >>>   };
> >>>   -static void apic_init(APICCommonState *s)
> >>> +static void apic_realize(DeviceState *dev, Error **errp)
> >>>   {
> >>> +    APICCommonState *s = APIC_COMMON(dev);
> >>> +
> >>>       memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, 
> >>> s, "apic-msi",
> >>>                             APIC_SPACE_SIZE);
> >>>   @@ -886,7 +890,7 @@ static void apic_class_init(ObjectClass 
> >>> *klass, void *data)
> >>>   {
> >>>       APICCommonClass *k = APIC_COMMON_CLASS(klass);
> >>>   -    k->init = apic_init;
> >>> +    k->realize = apic_realize;
> >>>       k->set_base = apic_set_base;
> >>>       k->set_tpr = apic_set_tpr;
> >>>       k->get_tpr = apic_get_tpr;
> >>> @@ -897,7 +901,7 @@ static void apic_class_init(ObjectClass *klass, 
> >>> void *data)
> >>>   }
> >>>     static const TypeInfo apic_info = {
> >>> -    .name          = "apic",
> >>> +    .name          = TYPE_APIC,
> >>>       .instance_size = sizeof(APICCommonState),
> >>>       .parent        = TYPE_APIC_COMMON,
> >>>       .class_init    = apic_class_init,
> >>> diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
> >>> index f3edf48..5a413cc 100644
> >>> --- a/hw/intc/apic_common.c
> >>> +++ b/hw/intc/apic_common.c
> >>> @@ -284,7 +284,7 @@ static int apic_load_old(QEMUFile *f, void 
> >>> *opaque, int version_id)
> >>>       return 0;
> >>>   }
> >>>   -static int apic_init_common(ICCDevice *dev)
> >>> +static void apic_common_realize(DeviceState *dev, Error **errp)
> >>>   {
> >>>       APICCommonState *s = APIC_COMMON(dev);
> >>>       APICCommonClass *info;
> >>> @@ -293,14 +293,16 @@ static int apic_init_common(ICCDevice *dev)
> >>>       static bool mmio_registered;
> >>>         if (apic_no >= MAX_APICS) {
> >>> -        return -1;
> >>> +    error_setg(errp, "%s initialization failed.",
> >>           ^^
> >>> + object_get_typename(OBJECT(dev)));
> >>> +    return;
> >>>       }
> >> Indentation looks bad.
> >>
> >>>       s->idx = apic_no++;
> >>>         info = APIC_COMMON_GET_CLASS(s);
> >>> -    info->init(s);
> >>> +    info->realize(dev, errp);
> >>>       if (!mmio_registered) {
> >>> -        ICCBus *b = ICC_BUS(qdev_get_parent_bus(DEVICE(dev)));
> >>> +        ICCBus *b = ICC_BUS(qdev_get_parent_bus(dev));
> >>> memory_region_add_subregion(b->apic_address_space, 0, &s->io_memory);
> >>>           mmio_registered = true;
> >>>       }
> >>> @@ -315,7 +317,6 @@ static int apic_init_common(ICCDevice *dev)
> >>>           info->enable_tpr_reporting(s, true);
> >>>       }
> >>>   -    return 0;
> >>>   }
> >>>     static void apic_dispatch_pre_save(void *opaque)
> >>> @@ -388,7 +389,7 @@ static void apic_common_class_init(ObjectClass 
> >>> *klass, void *data)
> >>>       dc->reset = apic_reset_common;
> >>>       dc->no_user = 1;
> >>>       dc->props = apic_properties_common;
> >>> -    idc->init = apic_init_common;
> >>> +    idc->realize = apic_common_realize;
> >>>   }
> >>>     static const TypeInfo apic_common_type = {
> >>> diff --git a/include/hw/cpu/icc_bus.h b/include/hw/cpu/icc_bus.h
> >>> index b550070..b32a549 100644
> >>> --- a/include/hw/cpu/icc_bus.h
> >>> +++ b/include/hw/cpu/icc_bus.h
> >>> @@ -66,7 +66,8 @@ typedef struct ICCDeviceClass {
> >>>       DeviceClass parent_class;
> >>>       /*< public >*/
> >>>   -    int (*init)(ICCDevice *dev); /* TODO replace with QOM realize */
> >>> +    /* QOM realize */
> >>> +    DeviceRealize realize;
> >> Maybe adding 'realize' in ICCDeviceClass is redundant, because parent
> >> class has included 'realize' field.
> >>
> >>>   } ICCDeviceClass;
> >>>     #define TYPE_ICC_DEVICE "icc-device"
> >>> diff --git a/include/hw/i386/apic_internal.h 
> >>> b/include/hw/i386/apic_internal.h
> >>> index 1b0a7fb..bd3a5fc 100644
> >>> --- a/include/hw/i386/apic_internal.h
> >>> +++ b/include/hw/i386/apic_internal.h
> >>> @@ -79,8 +79,9 @@ typedef struct APICCommonState APICCommonState;
> >>>   typedef struct APICCommonClass
> >>>   {
> >>>       ICCDeviceClass parent_class;
> >>> -
> >>> -    void (*init)(APICCommonState *s);
> >>> +
> >>> +    /* QOM realize */
> >>> +    DeviceRealize realize;
> >> as above.
> >>
> >> Thanks,
> >> Chen
> >>>       void (*set_base)(APICCommonState *s, uint64_t val);
> >>>       void (*set_tpr)(APICCommonState *s, uint8_t val);
> >>>       uint8_t (*get_tpr)(APICCommonState *s);
> >>
> > Thanks for your review!!
> Hi, Chen Fan:
> 
> In my understanding, If we use only one 'realize'(which in 
> 'DeviceClass'), I think all the initialization work must be done in the 
> leaf child.  if we add 'redundant' realize to each parent, then we can 
> call the initialization chain from DeviceClass down to leaf child's 
> parent, with each parent complete a bit further(of cause, a parent can 
> do nothing and pass to it's child directly).
> 
Hi Zhao,
  I may not agree with your point of view, As far as I know，usually, we
must override the 'dc->realize' pointer function to initialize a device
via setting 'realize' property to 'true', e.g.
object_property_set_bool('realize', true), this would call the realize
function of the device, If we want call the initialization chain from
'DeviceClass' down to leaf, we should add a 'parent_realize' field to
realize parent device. not long ago， I had sent a path about refactor
apic, though, there was not commented, if you are interested in it，
please help to review it:
https://lists.gnu.org/archive/html/qemu-devel/2013-10/msg02823.html 

Thanks,
Chen

> What do you think?
> 
>