[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v6 02/17] Add accelerator id and model name to C
From: |
Michael Mueller |
Subject: |
Re: [Qemu-devel] [PATCH v6 02/17] Add accelerator id and model name to CPUState |
Date: |
Wed, 6 May 2015 11:59:38 +0200 |
On Tue, 5 May 2015 10:26:02 -0300
Eduardo Habkost <address@hidden> wrote:
> On Mon, Apr 27, 2015 at 04:53:16PM +0200, Michael Mueller wrote:
> > The patch defines ids per accelerator and adds the accel_id and
> > the model_name to the CPUState. The accel_id is initialized by
> > common code, the model name needs to be initialized by target
> > specific code.
> >
> > Signed-off-by: Michael Mueller <address@hidden>
> > Acked-by: Christian Borntraeger <address@hidden>
> > ---
> > include/qom/cpu.h | 5 +++++
> > qapi-schema.json | 9 +++++++++
> > qom/cpu.c | 14 ++++++++++++++
> > 3 files changed, 28 insertions(+)
> >
> > diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> > index 9dafb48..4ffc050 100644
> > --- a/include/qom/cpu.h
> > +++ b/include/qom/cpu.h
> > @@ -236,6 +236,8 @@ struct kvm_run;
> > * @mem_io_pc: Host Program Counter at which the memory was accessed.
> > * @mem_io_vaddr: Target virtual address at which the memory was accessed.
> > * @kvm_fd: vCPU file descriptor for KVM.
> > + * @accel_id: accelerator id of this CPU.
> > + * @model_name: model name of this CPU
> > *
> > * State of one CPU core or thread.
> > */
> > @@ -313,6 +315,9 @@ struct CPUState {
> > (absolute value) offset as small as possible. This reduces code
> > size, especially for hosts without large memory offsets. */
> > volatile sig_atomic_t tcg_exit_req;
> > +
> > + AccelId accel_id;
>
> This can be a AccelState pointer, set on initialization, because we have
> another user case for having a AccelState pointer: query-cpu-definition
> implementations may create temporary CPU objects with a different accel
> object to be able to probe for accel-specific data.
>
> (The pointer may become a link QOM property later.)
>
>
> > + char *model_name;
> > };
> >
> > QTAILQ_HEAD(CPUTailQ, CPUState);
> > diff --git a/qapi-schema.json b/qapi-schema.json
> > index ac9594d..540e520 100644
> > --- a/qapi-schema.json
> > +++ b/qapi-schema.json
> > @@ -2515,6 +2515,15 @@
> > ##
> > { 'command': 'query-machines', 'returns': ['MachineInfo'] }
> >
> > +# @AccelId
> > +#
> > +# Defines accelerator ids
> > +#
> > +# Since: 2.4
> > +##
> > +{ 'enum': 'AccelId',
> > + 'data': ['qtest', 'tcg', 'kvm', 'xen'] }
> > +
>
> Not sure if it is better to have an enum or simply a string here.
>
> > ##
> > # @CpuDefinitionInfo:
> > #
> > diff --git a/qom/cpu.c b/qom/cpu.c
> > index 108bfa2..457afc7 100644
> > --- a/qom/cpu.c
> > +++ b/qom/cpu.c
> > @@ -67,6 +67,20 @@ CPUState *cpu_generic_init(const char *typename, const
> > char *cpu_model)
> > goto out;
> > }
> >
> > + if (tcg_enabled()) {
> > + cpu->accel_id = ACCEL_ID_TCG;
> > + } else if (kvm_enabled()) {
> > + cpu->accel_id = ACCEL_ID_KVM;
> > + }
> > +#ifdef CONFIG_XEN
> > + else if (xen_enabled()) {
> > + cpu->accel_id = ACCEL_ID_XEN;
> > + }
> > +#endif
> > + else {
> > + cpu->accel_id = ACCEL_ID_QTEST;
> > + }
>
> You can simply use ACCEL_GET_CLASS(current_machine->accelerator)->name
> here. If we really want an enum, we can add an AccelId field to
> AccelClass, and initialize it properly on the accel class_init
> functions.
The AccelClass (ac = ACCEL_GET_CLASS(current_machine->accelerator) would be ok
though.
That will allow to access the ac->accel_id (not yet there) at places where
required.
I'm just not sure how to access current_machine here.
>
> CONFIG_USER may require some special code when returning the accelerator
> ID as "tcg" because IIRC it doesn't use the QOM accel classes (yet).
>
> > +
> > object_property_set_bool(OBJECT(cpu), true, "realized", &err);
> >
> > out:
> > --
> > 1.8.3.1
> >
>