Re: [Qemu-devel] [PATCH 22/22] core/sysbus: remove the SysBusDeviceClass::initpath

From: Peter Maydell <peter.maydell@linaro.org>
To: maozy <maozhongyi@cmss.chinamobile.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>,
	QEMU Developers <qemu-devel@nongnu.org>,
	Thomas Huth <thuth@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Markus Armbruster <armbru@redhat.com>,
	Richard Henderson <richard.henderson@linaro.org>,
	Alistair Francis <alistair.francis@wdc.com>,
	Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Subject: Re: [Qemu-devel] [PATCH 22/22] core/sysbus: remove the SysBusDeviceClass::initpath
Date: Fri, 23 Nov 2018 09:02:29 +0000	[thread overview]
Message-ID: <CAFEAcA_tmLbierkqRP6E3QDV89aAOASRdsA5-rt3TyeWE0tE0g@mail.gmail.com> (raw)
In-Reply-To: <bb601691-a96d-8968-bb5b-0b15757285f6@cmss.chinamobile.com>

On 23 November 2018 at 03:10, maozy <maozhongyi@cmss.chinamobile.com> wrote:
> In order to void the subclasses whose parent_realize field is
> set to NULL, the k->realize function must be retained even
> though it doesn't do anything practical. Just like this:
>
>
> -/* TODO remove once all sysbus devices have been converted to realize*/
>  static void sysbus_realize(DeviceState *dev, Error **errp)
>  {
> -    SysBusDevice *sd = SYS_BUS_DEVICE(dev);
> -    SysBusDeviceClass *sbc = SYS_BUS_DEVICE_GET_CLASS(sd);
> -
> -    if (!sbc->init) {
> -        return;
> -    }
> -    if (sbc->init(sd) < 0) {
> -        error_setg(errp, "Device initialization failed");
> -    }
>  }
>
> it doesn't look elegant, but I didn't think of a better way, if you
> can give me some hints, I really appreciate it. :)

If we do take this approach, we should have a comment which
says why we have an empty realize function, so that we don't
in future forget and delete the apparently unnecessary code...

thanks
-- PMM