On Thu, 30 Apr 2015 16:19:07 -0300
Eduardo Habkost <ehabk...@redhat.com> 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.
provided the way cpu_index is generated, path won't be predictable/stable
with CPU unplug. I'd rather use DEVICE->id instead of cpu_index.
>
> Signed-off-by: Eduardo Habkost <ehabk...@redhat.com>
> ---
> 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 <ehabk...@redhat.com>
> Subject: Re: [Qemu-devel] cpu modelling and hotplug (was: [PATCH RFC 0/4]
> target-i386: PC socket/core/thread modeling, part 1)
> Message-ID: <20150423131736.ga17...@thinpad.lan.raisama.net>
> ---
> 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);
> +
> + cpu->self = cobj;
> + 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;
