> From: wangyanan (Y) > Sent: Tuesday, May 18, 2021 5:43 AM > > Hi Salil, > > On 2021/5/18 4:48, Salil Mehta wrote: > >> From: Qemu-arm > [mailto:qemu-arm-bounces+salil.mehta=huawei....@nongnu.org] > >> On Behalf Of Yanan Wang > >> Sent: Sunday, May 16, 2021 11:29 AM > >> To: Peter Maydell <peter.mayd...@linaro.org>; Andrew Jones > >> <drjo...@redhat.com>; Michael S . Tsirkin <m...@redhat.com>; Igor Mammedov > >> <imamm...@redhat.com>; Shannon Zhao <shannon.zha...@gmail.com>; Alistair > >> Francis <alistair.fran...@wdc.com>; David Gibson > >> <da...@gibson.dropbear.id.au>; qemu-devel@nongnu.org; qemu-...@nongnu.org > >> Cc: Song Bao Hua (Barry Song) <song.bao....@hisilicon.com>; zhukeqian > >> <zhukeqi...@huawei.com>; yangyicong <yangyic...@huawei.com>; Zengtao (B) > >> <prime.z...@hisilicon.com>; Wanghaibin (D) <wanghaibin.w...@huawei.com>; > >> yuzenghui <yuzeng...@huawei.com>; Paolo Bonzini <pbonz...@redhat.com>; > >> Philippe Mathieu-Daudé <phi...@redhat.com> > >> Subject: [RFC PATCH v3 4/9] hw/arm/virt: Initialize the present cpu members > >> > >> We create and initialize a cpuobj for each present cpu in > >> machvirt_init(). Now we also initialize the cpu member of > >> structure CPUArchId for each present cpu in the function. > > [...] > > > >> qdev_realize(DEVICE(cpuobj), NULL, &error_fatal); > >> + > >> + /* > >> + * As ARM cpu hotplug is not supported yet, we initialize > >> + * the present cpu members here. > >> + */ > >> + machine->possible_cpus->cpus[n].cpu = cpuobj; > > > > when vcpu Hotplug is not supported yet, what necessitates this change now? > > > The initialization will gives a way to determine whether a CPU is > present or not. > At least, for now it will be used when generating ACPI tables, e.g. > DSDT, MADT. > See patch 5 and 6.
yes, but why do you require it now as part of the vcpu topology change? As-far-as-i-can-see, PPTT table changes(part of patch 5/9) do not require this change. Change in Patch 5/9 has also been done in anticipation of some future requirement(vcpu Hotplug?). Please correct me here if I am wrong? Thanks
