Re: [Qemu-devel] [PATCH 03/11] acpi: factor out common cpu hotplug code for PIIX4/Q35

["Michael S. Tsirkin" <mst@redhat.com>]

On Fri, Dec 13, 2013 at 05:22:08PM +0100, Igor Mammedov wrote:
> .. so it could be used for adding CPU hotplug to Q35 machine
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>

Sounds good but please call this file cpu_hotplug.c/.h or cpu-hotplug.c/h
and make all prefixes acpi_cpu_hotplug and AcpiCpuHotplug.


> ---
>  hw/acpi/Makefile.objs     |  2 +-
>  hw/acpi/hotplug.c         | 65 +++++++++++++++++++++++++++++++++++++++
>  hw/acpi/piix4.c           | 78 +++++------------------------------------------
>  include/hw/acpi/hotplug.h | 31 +++++++++++++++++++
>  4 files changed, 104 insertions(+), 72 deletions(-)
>  create mode 100644 hw/acpi/hotplug.c
>  create mode 100644 include/hw/acpi/hotplug.h
> 
> diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
> index a0b63b5..41dec06 100644
> --- a/hw/acpi/Makefile.objs
> +++ b/hw/acpi/Makefile.objs
> @@ -1,2 +1,2 @@
> -common-obj-$(CONFIG_ACPI) += core.o piix4.o ich9.o
> +common-obj-$(CONFIG_ACPI) += core.o piix4.o ich9.o hotplug.o
>  
> diff --git a/hw/acpi/hotplug.c b/hw/acpi/hotplug.c
> new file mode 100644
> index 0000000..fcc0988
> --- /dev/null
> +++ b/hw/acpi/hotplug.c
> @@ -0,0 +1,65 @@
> +/*
> + * QEMU ACPI hotplug utilities
> + *
> + * Copyright (C) 2013 Red Hat Inc
> + *
> + * Authors:
> + *   Igor Mammedov <imammedo@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +#include "hw/hw.h"
> +#include "hw/acpi/hotplug.h"
> +
> +static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size)
> +{
> +    AcpiCPUHotplug *cpus = opaque;
> +    uint64_t val = cpus->sts[addr];
> +
> +    return val;
> +}
> +
> +static void cpu_status_write(void *opaque, hwaddr addr, uint64_t data,
> +                             unsigned int size)
> +{
> +    /* TODO: implement VCPU removal on guest signal that CPU can be removed */
> +}
> +
> +static const MemoryRegionOps acpi_cpu_hotplug_ops = {
> +    .read = cpu_status_read,
> +    .write = cpu_status_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 1,
> +        .max_access_size = 1,
> +    },
> +};
> +
> +void acpi_hotplug_cpu_add(ACPIGPE *gpe, AcpiCPUHotplug *g, CPUState *cpu)
> +{
> +    CPUClass *k = CPU_GET_CLASS(cpu);
> +    int64_t cpu_id;
> +
> +    *gpe->sts = *gpe->sts | ACPI_CPU_HOTPLUG_STATUS;
> +    cpu_id = k->get_arch_id(CPU(cpu));
> +    g->sts[cpu_id / 8] |= (1 << (cpu_id % 8));
> +}
> +
> +void acpi_hotplug_cpu_init(MemoryRegion *parent, Object *owner,
> +                           AcpiCPUHotplug *gpe_cpu, uint16_t base)
> +{
> +    CPUState *cpu;
> +
> +    CPU_FOREACH(cpu) {
> +        CPUClass *cc = CPU_GET_CLASS(cpu);
> +        int64_t id = cc->get_arch_id(cpu);
> +
> +        g_assert((id / 8) < ACPI_GPE_PROC_LEN);
> +        gpe_cpu->sts[id / 8] |= (1 << (id % 8));
> +    }
> +    gpe_cpu->io_base = base;
> +    memory_region_init_io(&gpe_cpu->io, owner, &acpi_cpu_hotplug_ops,
> +                          gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN);
> +    memory_region_add_subregion(parent, gpe_cpu->io_base, &gpe_cpu->io);
> +}
> diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> index b6b97ce..8ab85b2 100644
> --- a/hw/acpi/piix4.c
> +++ b/hw/acpi/piix4.c
> @@ -30,6 +30,7 @@
>  #include "hw/nvram/fw_cfg.h"
>  #include "exec/address-spaces.h"
>  #include "hw/acpi/piix4.h"
> +#include "hw/acpi/hotplug.h"
>  
>  //#define DEBUG
>  
> @@ -50,20 +51,14 @@
>  #define PCI_RMV_BASE 0xae0c
>  
>  #define PIIX4_PROC_BASE 0xaf00
> -#define PIIX4_PROC_LEN 32
>  
>  #define PIIX4_PCI_HOTPLUG_STATUS 2
> -#define PIIX4_CPU_HOTPLUG_STATUS 4
>  
>  struct pci_status {
>      uint32_t up; /* deprecated, maintained for migration compatibility */
>      uint32_t down;
>  };
>  
> -typedef struct CPUStatus {
> -    uint8_t sts[PIIX4_PROC_LEN];
> -} CPUStatus;
> -
>  typedef struct PIIX4PMState {
>      /*< private >*/
>      PCIDevice parent_obj;
> @@ -74,7 +69,6 @@ typedef struct PIIX4PMState {
>  
>      MemoryRegion io_gpe;
>      MemoryRegion io_pci;
> -    MemoryRegion io_cpu;
>      ACPIREGS ar;
>  
>      APMState apm;
> @@ -97,7 +91,7 @@ typedef struct PIIX4PMState {
>      uint8_t disable_s4;
>      uint8_t s4_val;
>  
> -    CPUStatus gpe_cpu;
> +    AcpiCPUHotplug gpe_cpu;
>      Notifier cpu_added_notifier;
>  } PIIX4PMState;
>  
> @@ -628,61 +622,13 @@ static const MemoryRegionOps piix4_pci_ops = {
>      },
>  };
>  
> -static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size)
> -{
> -    PIIX4PMState *s = opaque;
> -    CPUStatus *cpus = &s->gpe_cpu;
> -    uint64_t val = cpus->sts[addr];
> -
> -    return val;
> -}
> -
> -static void cpu_status_write(void *opaque, hwaddr addr, uint64_t data,
> -                             unsigned int size)
> -{
> -    /* TODO: implement VCPU removal on guest signal that CPU can be removed */
> -}
> -
> -static const MemoryRegionOps cpu_hotplug_ops = {
> -    .read = cpu_status_read,
> -    .write = cpu_status_write,
> -    .endianness = DEVICE_LITTLE_ENDIAN,
> -    .valid = {
> -        .min_access_size = 1,
> -        .max_access_size = 1,
> -    },
> -};
> -
> -typedef enum {
> -    PLUG,
> -    UNPLUG,
> -} HotplugEventType;
> -
> -static void piix4_cpu_hotplug_req(PIIX4PMState *s, CPUState *cpu,
> -                                  HotplugEventType action)
> -{
> -    CPUStatus *g = &s->gpe_cpu;
> -    ACPIGPE *gpe = &s->ar.gpe;
> -    CPUClass *k = CPU_GET_CLASS(cpu);
> -    int64_t cpu_id;
> -
> -    assert(s != NULL);
> -
> -    *gpe->sts = *gpe->sts | PIIX4_CPU_HOTPLUG_STATUS;
> -    cpu_id = k->get_arch_id(CPU(cpu));
> -    if (action == PLUG) {
> -        g->sts[cpu_id / 8] |= (1 << (cpu_id % 8));
> -    } else {
> -        g->sts[cpu_id / 8] &= ~(1 << (cpu_id % 8));
> -    }
> -    acpi_update_sci(&s->ar, s->irq);
> -}
> -
>  static void piix4_cpu_added_req(Notifier *n, void *opaque)
>  {
>      PIIX4PMState *s = container_of(n, PIIX4PMState, cpu_added_notifier);
>  
> -    piix4_cpu_hotplug_req(s, CPU(opaque), PLUG);
> +    assert(s != NULL);
> +    acpi_hotplug_cpu_add(&s->ar.gpe, &s->gpe_cpu, CPU(opaque));
> +    acpi_update_sci(&s->ar, s->irq);
>  }
>  
>  static int piix4_device_hotplug(DeviceState *qdev, PCIDevice *dev,
> @@ -691,8 +637,6 @@ static int piix4_device_hotplug(DeviceState *qdev, PCIDevice *dev,
>  static void piix4_acpi_system_hot_add_init(MemoryRegion *parent,
>                                             PCIBus *bus, PIIX4PMState *s)
>  {
> -    CPUState *cpu;
> -
>      memory_region_init_io(&s->io_gpe, OBJECT(s), &piix4_gpe_ops, s,
>                            "acpi-gpe0", GPE_LEN);
>      memory_region_add_subregion(parent, GPE_BASE, &s->io_gpe);
> @@ -703,16 +647,8 @@ static void piix4_acpi_system_hot_add_init(MemoryRegion *parent,
>                                  &s->io_pci);
>      pci_bus_hotplug(bus, piix4_device_hotplug, DEVICE(s));
>  
> -    CPU_FOREACH(cpu) {
> -        CPUClass *cc = CPU_GET_CLASS(cpu);
> -        int64_t id = cc->get_arch_id(cpu);
> -
> -        g_assert((id / 8) < PIIX4_PROC_LEN);
> -        s->gpe_cpu.sts[id / 8] |= (1 << (id % 8));
> -    }
> -    memory_region_init_io(&s->io_cpu, OBJECT(s), &cpu_hotplug_ops, s,
> -                          "acpi-cpu-hotplug", PIIX4_PROC_LEN);
> -    memory_region_add_subregion(parent, PIIX4_PROC_BASE, &s->io_cpu);
> +    acpi_hotplug_cpu_init(parent, OBJECT(s), &s->gpe_cpu,
> +                          PIIX4_PROC_BASE);
>      s->cpu_added_notifier.notify = piix4_cpu_added_req;
>      qemu_register_cpu_added_notifier(&s->cpu_added_notifier);
>  }
> diff --git a/include/hw/acpi/hotplug.h b/include/hw/acpi/hotplug.h
> new file mode 100644
> index 0000000..8bc176b
> --- /dev/null
> +++ b/include/hw/acpi/hotplug.h
> @@ -0,0 +1,31 @@
> +/*
> + * QEMU ACPI hotplug utilities
> + *
> + * Copyright (C) 2013 Red Hat Inc
> + *
> + * Authors:
> + *   Igor Mammedov <imammedo@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +#ifndef ACPI_HOTPLUG_H
> +#define ACPI_HOTPLUG_H
> +
> +#include "hw/acpi/acpi.h"
> +
> +#define ACPI_CPU_HOTPLUG_STATUS 4
> +
> +#define ACPI_GPE_PROC_LEN 32
> +
> +typedef struct AcpiCPUHotplug {
> +    MemoryRegion io;
> +    uint16_t io_base;
> +    uint8_t sts[ACPI_GPE_PROC_LEN];
> +} AcpiCPUHotplug;
> +
> +void acpi_hotplug_cpu_add(ACPIGPE *gpe, AcpiCPUHotplug *g, CPUState *cpu);
> +
> +void acpi_hotplug_cpu_init(MemoryRegion *parent, Object *owner,
> +                           AcpiCPUHotplug *gpe_cpu, uint16_t base);
> +#endif
> -- 
> 1.8.3.1