qemu-trivial
[Top][All Lists]
Advanced

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

Re: [PATCH v4 3/3] target/i386: Restrict X86CPUFeatureWord to X86 target


From: Eduardo Habkost
Subject: Re: [PATCH v4 3/3] target/i386: Restrict X86CPUFeatureWord to X86 targets
Date: Thu, 1 Oct 2020 11:53:47 -0400

On Thu, Oct 01, 2020 at 05:37:26PM +0200, Philippe Mathieu-Daudé wrote:
> On 10/1/20 5:29 PM, Eduardo Habkost wrote:
> > On Thu, Oct 01, 2020 at 04:41:52PM +0200, Philippe Mathieu-Daudé wrote:
> >> Only qemu-system-FOO and qemu-storage-daemon provide QMP
> >> monitors, therefore such declarations and definitions are
> >> irrelevant for user-mode emulation.
> >>
> >> Restricting the x86-specific commands to machine-target.json
> >> pulls less QAPI-generated code into user-mode.
> > 
> > Is this still true without "qapi: Restrict code generated for
> > user-mode"?
> 
> The correct description so far is:
> 
> "Restricting the x86-specific commands to machine-target.json
> pulls less QAPI-generated code into non-x86 targets.", as of
> this commit the X86CPURegister32 definitions are not built in
> the other ARM/S390/PPC/... targets.

This seems to have other side effects in addition to remove the
code from non-x86 targets and I don't understand why.

> 
> I still have some hope "qapi: Restrict code generated for user-mode"
> get merged some day.
> 
> > 
> > Markus, Eric: what's the difference between machine.json and
> > machine-target.json? commit 7f7b4e7abef4 ("qapi: Split
> > machine-target.json off target.json and misc.json") explains what
> > but not why.

[1]

> > 
> >>
> >> Acked-by: Richard Henderson <richard.henderson@linaro.org>
> >> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> > 
> > Why the visit_type_X86CPUFeatureWordInfoList() stub was required
> > in v3, but not in this version?
> 
> Because it is ifdef'ed out in the previous (new) patch:
> "target/i386/cpu: Restrict some of feature-words uses to system-mode".

Sorry for the confusion, I thought this patch was _before_
"Restrict some of feature-words ..".

Now, what I don't understand is: why moving the code from
machine.json to machine-target.json makes patch 2/3 necessary?
I assume the answer to the question above[1] would clarify this.

> 
> > 
> > 
> >> ---
> >>  qapi/machine-target.json | 45 ++++++++++++++++++++++++++++++++++++++++
> >>  qapi/machine.json        | 42 -------------------------------------
> >>  target/i386/cpu.c        |  2 +-
> >>  3 files changed, 46 insertions(+), 43 deletions(-)
> >>
> >> diff --git a/qapi/machine-target.json b/qapi/machine-target.json
> >> index 698850cc78..b4d769a53b 100644
> >> --- a/qapi/machine-target.json
> >> +++ b/qapi/machine-target.json
> >> @@ -4,6 +4,51 @@
> >>  # 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 756dacb06f..995e972858 100644
> >> --- a/qapi/machine.json
> >> +++ b/qapi/machine.json
> >> @@ -574,48 +574,6 @@
> >>     '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 9f72342506..848a65ded2 100644
> >> --- a/target/i386/cpu.c
> >> +++ b/target/i386/cpu.c
> >> @@ -38,7 +38,7 @@
> >>  #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"
> >> -- 
> >> 2.26.2
> >>
> > 
> 

-- 
Eduardo




reply via email to

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