Re: [Qemu-devel] [PATCH v2 1/3] pc-dimm: add a function to calculate VM's current RAM size

[zhanghailiang]

On 2014/11/19 18:32, Michael S. Tsirkin wrote:
> On Mon, Nov 17, 2014 at 01:11:08PM +0800, zhanghailiang wrote:
> > The global parameter 'ram_size' does not take into account
> > the hotplugged memory.
> >
> > In some codes, we use 'ram_size' as current VM's real RAM size,
> > which is not correct.
> >
> > Add function 'get_current_ram_size' to calculate VM's current RAM size,
> > it will enumerate present memory devices and also plus ram_size.
> >
> > Signed-off-by: zhanghailiang <address@hidden>
>
>
> This affects QMP right?

Yes, will affect the results of balloon commands ;)

> Cc Luiz.
>
>
> > ---
> >   hw/mem/pc-dimm.c                | 26 ++++++++++++++++++++++++++
> >   include/exec/cpu-common.h       |  1 +
> >   stubs/qmp_pc_dimm_device_list.c |  5 +++++
> >   3 files changed, 32 insertions(+)
> >
> > diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> > index a800ea7..38465d0 100644
> > --- a/hw/mem/pc-dimm.c
> > +++ b/hw/mem/pc-dimm.c
> > @@ -62,6 +62,32 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
> >       return 0;
> >   }
> >
> > +ram_addr_t get_current_ram_size(void)
> > +{
> > +    MemoryDeviceInfoList *info_list = NULL;
> > +    MemoryDeviceInfoList **prev = &info_list;
> > +    MemoryDeviceInfoList *info;
> > +    ram_addr_t size = ram_size;
> > +
> > +    qmp_pc_dimm_device_list(qdev_get_machine(), &prev);
> > +    for (info = info_list; info; info = info->next) {
> > +        MemoryDeviceInfo *value = info->value;
> > +
> > +        if (value) {
> > +            switch (value->kind) {
> > +            case MEMORY_DEVICE_INFO_KIND_DIMM:
> > +                size += value->dimm->size;
> > +                break;
> > +            default:
> > +                break;
> > +            }
> > +        }
> > +    }
> > +    qapi_free_MemoryDeviceInfoList(info_list);
> > +
> > +    return size;
> > +}
> > +
> >   static int pc_dimm_slot2bitmap(Object *obj, void *opaque)
> >   {
> >       unsigned long *bitmap = opaque;
> > diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
> > index 427b851..fcc3162 100644
> > --- a/include/exec/cpu-common.h
> > +++ b/include/exec/cpu-common.h
> > @@ -52,6 +52,7 @@ typedef uintptr_t ram_addr_t;
> >   #endif
> >
> >   extern ram_addr_t ram_size;
> > +ram_addr_t get_current_ram_size(void);
> >
> >   /* memory API */
> >
> > diff --git a/stubs/qmp_pc_dimm_device_list.c b/stubs/qmp_pc_dimm_device_list.c
> > index 5cb220c..b584bd8 100644
> > --- a/stubs/qmp_pc_dimm_device_list.c
> > +++ b/stubs/qmp_pc_dimm_device_list.c
> > @@ -5,3 +5,8 @@ int qmp_pc_dimm_device_list(Object *obj, void *opaque)
> >   {
> >      return 0;
> >   }
> > +
> > +ram_addr_t get_current_ram_size(void)
> > +{
> > +    return ram_size;
> > +}
> > --
> > 1.7.12.4
>
> .