Re: [PATCH v3 1/9] target/i386: Restrict X86CPUFeatureWord to X86 targets

[Markus Armbruster]

Philippe Mathieu-Daudé <address@hidden> writes:

> Move out x86-specific structures from generic machine code.
>
> Acked-by: Richard Henderson <address@hidden>
> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
> ---
>  qapi/machine-target.json   | 45 ++++++++++++++++++++++++++++++++++++++
>  qapi/machine.json          | 42 -----------------------------------
>  target/i386/cpu.c          |  2 +-
>  target/i386/machine-stub.c | 22 +++++++++++++++++++
>  target/i386/Makefile.objs  |  3 ++-
>  5 files changed, 70 insertions(+), 44 deletions(-)
>  create mode 100644 target/i386/machine-stub.c
>
> diff --git a/qapi/machine-target.json b/qapi/machine-target.json
> index f2c82949d8..fb7a4b7850 100644
> --- a/qapi/machine-target.json
> +++ b/qapi/machine-target.json
> @@ -3,6 +3,51 @@
>  # This work is licensed under the terms of the GNU GPL, version 2 or later.
>  # See the COPYING file in the top-level directory.
>  
> +##
> +# @X86CPURegister32:
> +#
> +# A X86 32-bit register
> +#
> +# Since: 1.5
> +##
> +{ 'enum': 'X86CPURegister32',
> +  'data': [ 'EAX', 'EBX', 'ECX', 'EDX', 'ESP', 'EBP', 'ESI', 'EDI' ],
> +  'if': 'defined(TARGET_I386)' }
> +
> +##
> +# @X86CPUFeatureWordInfo:
> +#
> +# Information about a X86 CPU feature word
> +#
> +# @cpuid-input-eax: Input EAX value for CPUID instruction for that feature 
> word
> +#
> +# @cpuid-input-ecx: Input ECX value for CPUID instruction for that
> +#                   feature word
> +#
> +# @cpuid-register: Output register containing the feature bits
> +#
> +# @features: value of output register, containing the feature bits
> +#
> +# Since: 1.5
> +##
> +{ 'struct': 'X86CPUFeatureWordInfo',
> +  'data': { 'cpuid-input-eax': 'int',
> +            '*cpuid-input-ecx': 'int',
> +            'cpuid-register': 'X86CPURegister32',
> +            'features': 'int' },
> +  'if': 'defined(TARGET_I386)' }
> +
> +##
> +# @DummyForceArrays:
> +#
> +# Not used by QMP; hack to let us use X86CPUFeatureWordInfoList internally
> +#
> +# Since: 2.5
> +##
> +{ 'struct': 'DummyForceArrays',
> +  'data': { 'unused': ['X86CPUFeatureWordInfo'] },
> +  'if': 'defined(TARGET_I386)' }
> +
>  ##
>  # @CpuModelInfo:
>  #
> diff --git a/qapi/machine.json b/qapi/machine.json
> index ff7b5032e3..1fe31d374c 100644
> --- a/qapi/machine.json
> +++ b/qapi/machine.json
> @@ -511,48 +511,6 @@
>     'dst': 'uint16',
>     'val': 'uint8' }}
>  
> -##
> -# @X86CPURegister32:
> -#
> -# A X86 32-bit register
> -#
> -# Since: 1.5
> -##
> -{ 'enum': 'X86CPURegister32',
> -  'data': [ 'EAX', 'EBX', 'ECX', 'EDX', 'ESP', 'EBP', 'ESI', 'EDI' ] }
> -
> -##
> -# @X86CPUFeatureWordInfo:
> -#
> -# Information about a X86 CPU feature word
> -#
> -# @cpuid-input-eax: Input EAX value for CPUID instruction for that feature 
> word
> -#
> -# @cpuid-input-ecx: Input ECX value for CPUID instruction for that
> -#                   feature word
> -#
> -# @cpuid-register: Output register containing the feature bits
> -#
> -# @features: value of output register, containing the feature bits
> -#
> -# Since: 1.5
> -##
> -{ 'struct': 'X86CPUFeatureWordInfo',
> -  'data': { 'cpuid-input-eax': 'int',
> -            '*cpuid-input-ecx': 'int',
> -            'cpuid-register': 'X86CPURegister32',
> -            'features': 'int' } }
> -
> -##
> -# @DummyForceArrays:
> -#
> -# Not used by QMP; hack to let us use X86CPUFeatureWordInfoList internally
> -#
> -# Since: 2.5
> -##
> -{ 'struct': 'DummyForceArrays',
> -  'data': { 'unused': ['X86CPUFeatureWordInfo'] } }
> -
>  ##
>  # @NumaCpuOptions:
>  #
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 7a4a8e3847..832498c723 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -37,7 +37,7 @@
>  #include "qemu/option.h"
>  #include "qemu/config-file.h"
>  #include "qapi/error.h"
> -#include "qapi/qapi-visit-machine.h"
> +#include "qapi/qapi-visit-machine-target.h"
>  #include "qapi/qapi-visit-run-state.h"
>  #include "qapi/qmp/qdict.h"
>  #include "qapi/qmp/qerror.h"
> diff --git a/target/i386/machine-stub.c b/target/i386/machine-stub.c
> new file mode 100644
> index 0000000000..cb301af057
> --- /dev/null
> +++ b/target/i386/machine-stub.c
> @@ -0,0 +1,22 @@
> +/*
> + * QAPI x86 CPU features stub
> + *
> + * Copyright (c) 2020 Red Hat, Inc.
> + *
> + * Author:
> + *   Philippe Mathieu-Daudé <address@hidden>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qapi/error.h"
> +#include "qapi/qapi-visit-machine-target.h"
> +
> +void visit_type_X86CPUFeatureWordInfoList(Visitor *v, const char *name,
> +                                      X86CPUFeatureWordInfoList **obj,
> +                                      Error **errp)

Unusual indentation.

> +{
> +}

Two kinds of stubs: stubs that can get called, and stubs that exist only
to satisfy the linker.  Which kind is this one?

> diff --git a/target/i386/Makefile.objs b/target/i386/Makefile.objs
> index 48e0c28434..1cdfc9f50c 100644
> --- a/target/i386/Makefile.objs
> +++ b/target/i386/Makefile.objs
> @@ -17,6 +17,7 @@ obj-$(CONFIG_HAX) += hax-all.o hax-mem.o hax-posix.o
>  endif
>  obj-$(CONFIG_HVF) += hvf/
>  obj-$(CONFIG_WHPX) += whpx-all.o
> -endif
> +endif # CONFIG_SOFTMMU
>  obj-$(CONFIG_SEV) += sev.o
>  obj-$(call lnot,$(CONFIG_SEV)) += sev-stub.o
> +obj-$(call lnot,$(CONFIG_SOFTMMU)) += machine-stub.o

Suggest

   ifeq ($(CONFIG_SOFTMMU),y)
   ...
   else
   obj-y += machine-stub.o
   endif

Matter of taste.