qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH] cpu: Register QOM links at /machine/cpus/<index


From: Peter Crosthwaite
Subject: Re: [Qemu-devel] [PATCH] cpu: Register QOM links at /machine/cpus/<index>
Date: Thu, 30 Apr 2015 18:51:43 -0700

On Thu, Apr 30, 2015 at 12:19 PM, Eduardo Habkost <address@hidden> wrote:
> This will provide a predictable path for the CPU objects, and a more
> powerful alternative for the query-cpus QMP command, as now every QOM
> property on CPU objects can be easily queried.
>
> Signed-off-by: Eduardo Habkost <address@hidden>
> ---
> Note that this doesn't replace any future topology enumeration
> mechanisms we may choose to implement. It just replaces the existing
> topology-unaware VCPU enumeration mechanism that is query-cpus.
>
> Reference to previous discussion:
>
>   Date: Thu, 23 Apr 2015 10:17:36 -0300
>   From: Eduardo Habkost <address@hidden>
>   Subject: Re: [Qemu-devel] cpu modelling and hotplug (was: [PATCH RFC 0/4] 
> target-i386: PC socket/core/thread modeling, part 1)
>   Message-ID: <address@hidden>
> ---
>  exec.c            | 16 ++++++++++++++++
>  include/qom/cpu.h |  3 +++
>  2 files changed, 19 insertions(+)
>
> diff --git a/exec.c b/exec.c
> index ae37b98..8bdfa65 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -519,6 +519,20 @@ void tcg_cpu_address_space_init(CPUState *cpu, 
> AddressSpace *as)
>  }
>  #endif
>
> +static void cpu_add_qom_link(CPUState *cpu)
> +{
> +#if !defined(CONFIG_USER_ONLY)
> +    Object *cobj = OBJECT(cpu);
> +    Object *cpu_container = container_get(OBJECT(current_machine), "/cpus");
> +    char *path = g_strdup_printf("%d", cpu->cpu_index);
> +

This pathing is inconsistent with other arrayification efforts where
we use ../foo[N].
Do we need the container, can we just use /cpu[0], /cpu[1]?

> +    cpu->self = cobj;

Paolo's . property ideal is probably a winner, but see this discussion:

https://lists.gnu.org/archive/html/qemu-devel/2015-04/msg03557.html

for how to create RYO links with open coded setters and getters.
You could use the object itself as an opaque data and a trivial getter,
no setter and then you can get rid of the self pointer.

Regards,
Peter

> +    object_property_add_link(cpu_container, path, TYPE_CPU, &cpu->self, NULL,
> +                             OBJ_PROP_LINK_UNREF_ON_RELEASE, &error_abort);
> +    g_free(path);
> +#endif
> +}
> +
>  void cpu_exec_init(CPUArchState *env)
>  {
>      CPUState *cpu = ENV_GET_CPU(env);
> @@ -558,6 +572,8 @@ void cpu_exec_init(CPUArchState *env)
>      if (cc->vmsd != NULL) {
>          vmstate_register(NULL, cpu_index, cc->vmsd, cpu);
>      }
> +
> +    cpu_add_qom_link(cpu);
>  }
>
>  #if defined(CONFIG_USER_ONLY)
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index 39f0f19..c253420 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -246,6 +246,9 @@ struct CPUState {
>      DeviceState parent_obj;
>      /*< public >*/
>
> +    /* Needed for the /machine/cpus/<index> link */
> +    Object *self;
> +
>      int nr_cores;
>      int nr_threads;
>      int numa_node;
> --
> 2.1.0
>
>



reply via email to

[Prev in Thread] Current Thread [Next in Thread]