|
From: | Anthony Liguori |
Subject: | Re: [Qemu-devel] [PATCH v2 0/7] APIC/IOAPIC cleanup |
Date: | Thu, 19 Aug 2010 14:33:13 -0500 |
User-agent: | Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.11) Gecko/20100713 Lightning/1.0b1 Thunderbird/3.0.6 |
On 06/12/2010 04:14 PM, Blue Swirl wrote:
Clean up APIC and IOAPIC. Convert both devices to qdev. v1->v2: Remove apic.h reorganization. Add IOAPIC and APIC qdev conversions. Use CPUState also in 5/7. However on 6/7 we have to again use void * because of VMState limitations. VMState gurus, please comment.
I'm late to the game here, but I'm not sure converting the APIC to qdev makes a lot of sense conceptually.
qdev models devices that exist on a bus, but the local APIC actually lives on the processor core. It's extremely unique in that it actually maps a physical memory region different depending on the actual core. It really belongs as part of the CPU emulation and not as part of the device emulation.
For now, the practical problem is that you can't hotplug a CPU because that creates an APIC which lives on the Sysbus which does not allow hotplug. Making sysbus allow hotplug is definitely note the right answer though.
I think the options are to allow non-bus devices (like the APIC) or make the APIC a special case that's part of the CPU emulation.
Blue Swirl (7): ioapic: unexport ioapic_set_irq ioapic: convert to qdev apic: avoid passing CPUState from devices apic: avoid passing CPUState from CPU code apic: avoid using CPUState internals apic: convert to qdev apic: qdev conversion cleanup hw/apic.c | 174 +++++++++++++++++++++++----------------------- hw/apic.h | 21 ++++-- hw/ioapic.c | 47 ++++++++---- hw/pc.c | 74 ++++++++++++++++++-- hw/pc.h | 4 +- hw/pc_piix.c | 19 +++++- qemu-common.h | 2 +- target-i386/cpu.h | 28 +++++--- target-i386/cpuid.c | 6 ++ target-i386/helper.c | 4 +- target-i386/kvm.c | 14 ++-- target-i386/op_helper.c | 8 +- 12 files changed, 258 insertions(+), 143 deletions(-)
[Prev in Thread] | Current Thread | [Next in Thread] |