Re: [PATCH 4/7] hw/i386/pc_q35: Resolve redundant q35_host variable

[BALATON Zoltan]

On Fri, 27 Jan 2023, Bernhard Beschow wrote:
> The variable is redundant to "phb" and is never used by its real type.

Also replace qdev_get_machine() with reference already passed to init 
function. (Maybe worth mentioning in commit message even if too small 
change for a separate patch.)

> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> ---
> hw/i386/pc_q35.c | 22 ++++++++++------------
> 1 file changed, 10 insertions(+), 12 deletions(-)
>
> diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
> index 83c57c6eb1..dc94ce1081 100644
> --- a/hw/i386/pc_q35.c
> +++ b/hw/i386/pc_q35.c
> @@ -118,7 +118,6 @@ static void pc_q35_init(MachineState *machine)
>     PCMachineState *pcms = PC_MACHINE(machine);
>     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
>     X86MachineState *x86ms = X86_MACHINE(machine);
> -    Q35PCIHost *q35_host;
>     PCIHostState *phb;

The phb variable itself is only used once to get the bus from it and it's 
mostly cast to Object * so maybe store it in a variable of that type to 
remove most of the casts and IMO you can also remove PCIHostState *phb and 
just use:

host_bus = PCI_HOST_BRIDGE(phost)->bus;

Regards,
BALATON Zoltan

>     PCIBus *host_bus;
>     PCIDevice *lpc;
> @@ -206,10 +205,10 @@ static void pc_q35_init(MachineState *machine)
>     }
>
>     /* create pci host bus */
> -    q35_host = Q35_HOST_DEVICE(qdev_new(TYPE_Q35_HOST_DEVICE));
> +    phb = PCI_HOST_BRIDGE(qdev_new(TYPE_Q35_HOST_DEVICE));
>
>     if (pcmc->pci_enabled) {
> -        pci_hole64_size = object_property_get_uint(OBJECT(q35_host),
> +        pci_hole64_size = object_property_get_uint(OBJECT(phb),
>                                                    
> PCI_HOST_PROP_PCI_HOLE64_SIZE,
>                                                    &error_abort);
>     }
> @@ -218,22 +217,21 @@ static void pc_q35_init(MachineState *machine)
>     pc_memory_init(pcms, get_system_memory(), rom_memory, &ram_memory,
>                    pci_hole64_size);
>
> -    object_property_add_child(qdev_get_machine(), "q35", OBJECT(q35_host));
> -    object_property_set_link(OBJECT(q35_host), MCH_HOST_PROP_RAM_MEM,
> +    object_property_add_child(OBJECT(machine), "q35", OBJECT(phb));
> +    object_property_set_link(OBJECT(phb), MCH_HOST_PROP_RAM_MEM,
>                              OBJECT(ram_memory), NULL);
> -    object_property_set_link(OBJECT(q35_host), MCH_HOST_PROP_PCI_MEM,
> +    object_property_set_link(OBJECT(phb), MCH_HOST_PROP_PCI_MEM,
>                              OBJECT(pci_memory), NULL);
> -    object_property_set_link(OBJECT(q35_host), MCH_HOST_PROP_SYSTEM_MEM,
> +    object_property_set_link(OBJECT(phb), MCH_HOST_PROP_SYSTEM_MEM,
>                              OBJECT(get_system_memory()), NULL);
> -    object_property_set_link(OBJECT(q35_host), MCH_HOST_PROP_IO_MEM,
> +    object_property_set_link(OBJECT(phb), MCH_HOST_PROP_IO_MEM,
>                              OBJECT(system_io), NULL);
> -    object_property_set_int(OBJECT(q35_host), PCI_HOST_BELOW_4G_MEM_SIZE,
> +    object_property_set_int(OBJECT(phb), PCI_HOST_BELOW_4G_MEM_SIZE,
>                             x86ms->below_4g_mem_size, NULL);
> -    object_property_set_int(OBJECT(q35_host), PCI_HOST_ABOVE_4G_MEM_SIZE,
> +    object_property_set_int(OBJECT(phb), PCI_HOST_ABOVE_4G_MEM_SIZE,
>                             x86ms->above_4g_mem_size, NULL);
>     /* pci */
> -    sysbus_realize_and_unref(SYS_BUS_DEVICE(q35_host), &error_fatal);
> -    phb = PCI_HOST_BRIDGE(q35_host);
> +    sysbus_realize_and_unref(SYS_BUS_DEVICE(phb), &error_fatal);
>     host_bus = phb->bus;
>     /* create ISA bus */
>     lpc = pci_create_simple_multifunction(host_bus, PCI_DEVFN(ICH9_LPC_DEV,