On Wed, Aug 19, 2015 at 05:36:29PM +0800, Zhu Guihua wrote:
> From: Chen Fan <chen.fan.f...@cn.fujitsu.com>
>
> Replace mapping APIC at global system address space with
> mapping it at per-CPU address spaces.
Can you improve the commit message by explaining not just what is being
done, but why this is needed?
>
> Signed-off-by: Chen Fan <chen.fan.f...@cn.fujitsu.com>
> Signed-off-by: Zhu Guihua <zhugh.f...@cn.fujitsu.com>
> ---
> hw/i386/pc.c | 7 -------
> hw/intc/apic_common.c | 6 ------
> target-i386/cpu.c | 21 +++++++++++++++++++++
> 3 files changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 9f2924e..8b7dbe5 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1158,13 +1158,6 @@ void pc_cpus_init(const char *cpu_model, DeviceState
> *icc_bridge)
> object_unref(OBJECT(cpu));
> }
>
> - /* map APIC MMIO area if CPU has APIC */
> - if (cpu && cpu->apic_state) {
> - /* XXX: what if the base changes? */
> - sysbus_mmio_map_overlap(SYS_BUS_DEVICE(icc_bridge), 0,
> - APIC_DEFAULT_ADDRESS, 0x1000);
> - }
> -
> /* tell smbios about cpuid version and features */
> smbios_set_cpuid(cpu->env.cpuid_version, cpu->env.features[FEAT_1_EDX]);
> }
> diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
> index 0032b97..c0b32eb 100644
> --- a/hw/intc/apic_common.c
> +++ b/hw/intc/apic_common.c
> @@ -296,7 +296,6 @@ static void apic_common_realize(DeviceState *dev, Error
> **errp)
> APICCommonClass *info;
> static DeviceState *vapic;
> static int apic_no;
> - static bool mmio_registered;
>
> if (apic_no >= MAX_APICS) {
> error_setg(errp, "%s initialization failed.",
> @@ -307,11 +306,6 @@ static void apic_common_realize(DeviceState *dev, Error
> **errp)
>
> info = APIC_COMMON_GET_CLASS(s);
> info->realize(dev, errp);
> - if (!mmio_registered) {
> - ICCBus *b = ICC_BUS(qdev_get_parent_bus(dev));
> - memory_region_add_subregion(b->apic_address_space, 0, &s->io_memory);
> - mmio_registered = true;
> - }
>
> /* Note: We need at least 1M to map the VAPIC option ROM */
> if (!vapic && s->vapic_control & VAPIC_ENABLE_MASK &&
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index cfb8aa7..8eed88c 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -2745,6 +2745,7 @@ static void x86_cpu_apic_create(X86CPU *cpu, Error
> **errp)
> /* TODO: convert to link<> */
> apic = APIC_COMMON(cpu->apic_state);
> apic->cpu = cpu;
> + apic->apicbase = APIC_DEFAULT_ADDRESS | MSR_IA32_APICBASE_ENABLE;
> }
>
> static void x86_cpu_apic_realize(X86CPU *cpu, Error **errp)
> @@ -2789,8 +2790,10 @@ static void x86_cpu_realizefn(DeviceState *dev, Error
> **errp)
> X86CPU *cpu = X86_CPU(dev);
> X86CPUClass *xcc = X86_CPU_GET_CLASS(dev);
> CPUX86State *env = &cpu->env;
> + APICCommonState *apic;
> Error *local_err = NULL;
> static bool ht_warned;
> + static bool apic_mmio_map_once;
>
> if (cpu->apic_id < 0) {
> error_setg(errp, "apic-id property was not initialized properly");
> @@ -2877,6 +2880,24 @@ static void x86_cpu_realizefn(DeviceState *dev, Error
> **errp)
> if (local_err != NULL) {
> goto out;
> }
> +
> + /* map APIC MMIO area */
> + apic = APIC_COMMON(cpu->apic_state);
> + if (tcg_enabled()) {
> + memory_region_add_subregion_overlap(cpu->cpu_as_root,
> + apic->apicbase &
> + MSR_IA32_APICBASE_BASE,
> + &apic->io_memory,
> + 0x1000);
Why exactly is this necessary? If this is necessary, why don't we need
to do this for non-TCG accelerators?
> + } else if (!apic_mmio_map_once) {
> + memory_region_add_subregion_overlap(get_system_memory(),
> + apic->apicbase &
> + MSR_IA32_APICBASE_BASE,
> + &apic->io_memory,
> + 0x1000);
> + apic_mmio_map_once = true;
> + }
I see that you are doing two things at the same time:
1) Moving the memory region registration to x86_cpu_realizefn();
2) Adding a special case for TCG that uses cpu->cpu_as_root.
Doing this in two separate patches seems more appropriate.
--
Eduardo
