Patchwork [07/22] target-i386: convert cpuid features into properties

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Submitter Igor Mammedov
Date Sept. 26, 2012, 8:32 p.m.
Message ID <1348691578-17231-8-git-send-email-imammedo@redhat.com>
Download mbox | patch
Permalink /patch/187203/
State New
Headers show

Comments

Igor Mammedov - Sept. 26, 2012, 8:32 p.m.
add property accessors for cpuid feature bits defined by
*_feature_name arrays.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v2:
  * replaced mask/ffs tricks by plain 'for (bit = 0; bit < 32; bit++)'
    as suggested by Eduardo Habkost
v3:
  * check if property exists before adding it
  * rebased on top of  "i386: cpu: remove duplicate feature names"
          http://www.mail-archive.com/qemu-devel@nongnu.org/msg129458.html
    place ext2_feature_name for AMD case into setter, so that not to
    clutter x86_cpu_realize() with property specific code.
  * fix for convert cpuid features
---
 target-i386/cpu.c |  114 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 114 insertions(+), 0 deletions(-)
H. Peter Anvin - Sept. 26, 2012, 9:31 p.m.
On 09/26/2012 01:32 PM, Igor Mammedov wrote:
> +
> +static void x86_cpuid_get_feature(Object *obj, Visitor *v, void *opaque,
> +                                         const char *name, Error **errp)
> +{
> +    X86CPU *cpu = X86_CPU(obj);
> +    CPUX86State *env = &cpu->env;
> +    bool value = true;
> +
> +    if (!is_feature_set(name, env->cpuid_features, feature_name) &&
> +       !is_feature_set(name, env->cpuid_ext_features, ext_feature_name) &&
> +       !is_feature_set(name, env->cpuid_ext2_features, ext2_feature_name) &&
> +       !is_feature_set(name, env->cpuid_ext3_features, ext3_feature_name) &&
> +       !is_feature_set(name, env->cpuid_kvm_features, kvm_feature_name) &&
> +       !is_feature_set(name, env->cpuid_svm_features, svm_feature_name)) {
> +        value = false;
> +    }
> +

If you're going to do a full-blown restructuring of the CPUID handling,
how about actually turning this into a composite object, specifically an
array, instead of this insane collection of arguments (which needs to be
augmented)?

	-hpa
Eduardo Habkost - Sept. 26, 2012, 9:39 p.m.
On Wed, Sep 26, 2012 at 02:31:25PM -0700, H. Peter Anvin wrote:
> On 09/26/2012 01:32 PM, Igor Mammedov wrote:
> > +
> > +static void x86_cpuid_get_feature(Object *obj, Visitor *v, void *opaque,
> > +                                         const char *name, Error **errp)
> > +{
> > +    X86CPU *cpu = X86_CPU(obj);
> > +    CPUX86State *env = &cpu->env;
> > +    bool value = true;
> > +
> > +    if (!is_feature_set(name, env->cpuid_features, feature_name) &&
> > +       !is_feature_set(name, env->cpuid_ext_features, ext_feature_name) &&
> > +       !is_feature_set(name, env->cpuid_ext2_features, ext2_feature_name) &&
> > +       !is_feature_set(name, env->cpuid_ext3_features, ext3_feature_name) &&
> > +       !is_feature_set(name, env->cpuid_kvm_features, kvm_feature_name) &&
> > +       !is_feature_set(name, env->cpuid_svm_features, svm_feature_name)) {
> > +        value = false;
> > +    }
> > +
> 
> If you're going to do a full-blown restructuring of the CPUID handling,
> how about actually turning this into a composite object, specifically an
> array, instead of this insane collection of arguments (which needs to be
> augmented)?

I have a series that does that, based on this one, that I will clean up
and submit after the other changes get in.

https://github.com/ehabkost/qemu-hacks/commits/work/cpuid-refactor-v0.22-2012-08-31

Patch

diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index a713960..213368b 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -833,6 +833,114 @@  static int check_features_against_host(x86_def_t *guest_def)
     return rv;
 }
 
+static bool is_feature_set(const char *name, const uint32_t featbitmap,
+                                  const char **featureset)
+{
+    uint32_t bit;
+
+    for (bit = 0; bit < 32; ++bit) {
+        if (featureset[bit] && !altcmp(name, NULL, featureset[bit])) {
+            if (featbitmap & (1 << bit)) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
+static void x86_cpuid_get_feature(Object *obj, Visitor *v, void *opaque,
+                                         const char *name, Error **errp)
+{
+    X86CPU *cpu = X86_CPU(obj);
+    CPUX86State *env = &cpu->env;
+    bool value = true;
+
+    if (!is_feature_set(name, env->cpuid_features, feature_name) &&
+       !is_feature_set(name, env->cpuid_ext_features, ext_feature_name) &&
+       !is_feature_set(name, env->cpuid_ext2_features, ext2_feature_name) &&
+       !is_feature_set(name, env->cpuid_ext3_features, ext3_feature_name) &&
+       !is_feature_set(name, env->cpuid_kvm_features, kvm_feature_name) &&
+       !is_feature_set(name, env->cpuid_svm_features, svm_feature_name)) {
+        value = false;
+    }
+
+    visit_type_bool(v, &value, name, errp);
+}
+
+static void x86_cpuid_set_feature(Object *obj, Visitor *v, void *opaque,
+                                         const char *name, Error **errp)
+{
+    X86CPU *cpu = X86_CPU(obj);
+    CPUX86State *env = &cpu->env;
+    uint32_t mask = 0;
+    uint32_t *dst_features;
+    bool value;
+
+    visit_type_bool(v, &value, name, errp);
+    if (error_is_set(errp)) {
+        return;
+    }
+
+    if (lookup_feature(&mask, name, NULL, feature_name)) {
+        dst_features = &env->cpuid_features;
+    } else if (lookup_feature(&mask, name, NULL, ext_feature_name)) {
+        dst_features = &env->cpuid_ext_features;
+    } else if (lookup_feature(&mask, name, NULL, ext2_feature_name)) {
+        dst_features = &env->cpuid_ext2_features;
+    } else if (lookup_feature(&mask, name, NULL, ext3_feature_name)) {
+        dst_features = &env->cpuid_ext3_features;
+    } else if (lookup_feature(&mask, name, NULL, kvm_feature_name)) {
+        dst_features = &env->cpuid_kvm_features;
+    } else if (lookup_feature(&mask, name, NULL, svm_feature_name)) {
+        dst_features = &env->cpuid_svm_features;
+    } else {
+        error_set(errp, QERR_PROPERTY_NOT_FOUND, "", name);
+        return;
+    }
+
+    if (value) {
+        *dst_features |= mask;
+    } else {
+        *dst_features &= ~mask;
+    }
+
+    /* On AMD CPUs, some CPUID[8000_0001].EDX bits must match the bits on
+     * CPUID[1].EDX.
+     */
+    if (dst_features == &env->cpuid_features &&
+            env->cpuid_vendor1 == CPUID_VENDOR_AMD_1 &&
+            env->cpuid_vendor2 == CPUID_VENDOR_AMD_2 &&
+            env->cpuid_vendor3 == CPUID_VENDOR_AMD_3) {
+        env->cpuid_ext2_features &= ~CPUID_EXT2_AMD_ALIASES;
+        env->cpuid_ext2_features |= *dst_features & CPUID_EXT2_AMD_ALIASES;
+    }
+}
+
+static void x86_register_cpuid_properties(Object *obj, const char **featureset)
+{
+    uint32_t bit;
+
+    for (bit = 0; bit < 32; ++bit) {
+        if (featureset[bit]) {
+            char *feature_name, *save_ptr;
+            char buf[32];
+            if (strlen(featureset[bit]) > sizeof(buf) - 1) {
+                abort();
+            }
+            pstrcpy(buf, sizeof(buf), featureset[bit]);
+            feature_name = strtok_r(buf, "|", &save_ptr);
+            while (feature_name) {
+                if (!object_property_find(obj, feature_name, NULL)) {
+                    object_property_add(obj, feature_name, "bool",
+                                    x86_cpuid_get_feature,
+                                    x86_cpuid_set_feature, NULL, NULL, NULL);
+                }
+                feature_name = strtok_r(NULL, "|", &save_ptr);
+            }
+        }
+    }
+}
+
 static void x86_cpuid_version_get_family(Object *obj, Visitor *v, void *opaque,
                                          const char *name, Error **errp)
 {
@@ -1920,6 +2028,12 @@  static void x86_cpu_initfn(Object *obj)
     object_property_add(obj, "tsc-frequency", "int",
                         x86_cpuid_get_tsc_freq,
                         x86_cpuid_set_tsc_freq, NULL, NULL, NULL);
+    x86_register_cpuid_properties(obj, feature_name);
+    x86_register_cpuid_properties(obj, ext_feature_name);
+    x86_register_cpuid_properties(obj, ext2_feature_name);
+    x86_register_cpuid_properties(obj, ext3_feature_name);
+    x86_register_cpuid_properties(obj, kvm_feature_name);
+    x86_register_cpuid_properties(obj, svm_feature_name);
 
     env->cpuid_apic_id = env->cpu_index;