Re: [Qemu-devel] [PATCH 32/37] target-i386: use static properties for setting cpuid features

[Don Slutz <Don@CloudSwitch.Com>]

On 10/22/12 11:03, Igor Mammedov wrote:
>   - def->kvm_features was used only for setting hadcoded defaults,
>     with defaults set by static props, we do not need it anymore,
>     ignore it in cpudef_2_x86_cpu().
>   - take in account CPUID_EXT_HYPERVISOR feature set by static
>     property default value;
>
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
>    * fix double free of features in cpu_x86_find_by_name()
> ---
>   target-i386/cpu.c | 271 +++++++-----------------------------------------------
>   1 file changed, 31 insertions(+), 240 deletions(-)
>
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index c804965..59809f8 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -87,31 +87,6 @@ static const char *ext3_feature_name[] = {
>       NULL, NULL, NULL, NULL,
>   };
>   
> -static const char *kvm_feature_name[] = {
> -    "kvmclock", "kvm_nopiodelay", "kvm_mmu", "kvmclock", "kvm_asyncpf", NULL, "kvm_pv_eoi", NULL,
> -    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
> -};
> -
> -static const char *svm_feature_name[] = {
> -    "npt", "lbrv", "svm_lock", "nrip_save",
> -    "tsc_scale", "vmcb_clean",  "flushbyasid", "decodeassists",
> -    NULL, NULL, "pause_filter", NULL,
> -    "pfthreshold", NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL,
> -};
> -
> -static const char *cpuid_7_0_ebx_feature_name[] = {
> -    NULL, NULL, NULL, NULL, NULL, NULL, NULL, "smep",
> -    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL, "smap", NULL, NULL, NULL,
> -    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
> -};
> -
>   #if defined(CONFIG_KVM)
>   static void x86_cpu_get_kvmclock(Object *obj, Visitor *v, void *opaque,
>                                    const char *name, Error **errp)
> @@ -752,88 +727,6 @@ void host_cpuid(uint32_t function, uint32_t count,
>   #endif
>   }
>   
> -#define iswhite(c) ((c) && ((c) <= ' ' || '~' < (c)))
> -
> -/* general substring compare of *[s1..e1) and *[s2..e2).  sx is start of
> - * a substring.  ex if !NULL points to the first char after a substring,
> - * otherwise the string is assumed to sized by a terminating nul.
> - * Return lexical ordering of *s1:*s2.
> - */
> -static int sstrcmp(const char *s1, const char *e1, const char *s2,
> -    const char *e2)
> -{
> -    for (;;) {
> -        if (!*s1 || !*s2 || *s1 != *s2)
> -            return (*s1 - *s2);
> -        ++s1, ++s2;
> -        if (s1 == e1 && s2 == e2)
> -            return (0);
> -        else if (s1 == e1)
> -            return (*s2);
> -        else if (s2 == e2)
> -            return (*s1);
> -    }
> -}
> -
> -/* compare *[s..e) to *altstr.  *altstr may be a simple string or multiple
> - * '|' delimited (possibly empty) strings in which case search for a match
> - * within the alternatives proceeds left to right.  Return 0 for success,
> - * non-zero otherwise.
> - */
> -static int altcmp(const char *s, const char *e, const char *altstr)
> -{
> -    const char *p, *q;
> -
> -    for (q = p = altstr; ; ) {
> -        while (*p && *p != '|')
> -            ++p;
> -        if ((q == p && !*s) || (q != p && !sstrcmp(s, e, q, p)))
> -            return (0);
> -        if (!*p)
> -            return (1);
> -        else
> -            q = ++p;
> -    }
> -}
> -
> -/* search featureset for flag *[s..e), if found set corresponding bit in
> - * *pval and return true, otherwise return false
> - */
> -static bool lookup_feature(uint32_t *pval, const char *s, const char *e,
> -                           const char **featureset)
> -{
> -    uint32_t mask;
> -    const char **ppc;
> -    bool found = false;
> -
> -    for (mask = 1, ppc = featureset; mask; mask <<= 1, ++ppc) {
> -        if (*ppc && !altcmp(s, e, *ppc)) {
> -            *pval |= mask;
> -            found = true;
> -        }
> -    }
> -    return found;
> -}
> -
> -static void add_flagname_to_bitmaps(const char *flagname, uint32_t *features,
> -                                    uint32_t *ext_features,
> -                                    uint32_t *ext2_features,
> -                                    uint32_t *ext3_features,
> -                                    uint32_t *kvm_features,
> -                                    uint32_t *svm_features,
> -                                    uint32_t *cpuid_7_0_ebx_features)
> -{
> -    if (!lookup_feature(features, flagname, NULL, feature_name) &&
> -        !lookup_feature(ext_features, flagname, NULL, ext_feature_name) &&
> -        !lookup_feature(ext2_features, flagname, NULL, ext2_feature_name) &&
> -        !lookup_feature(ext3_features, flagname, NULL, ext3_feature_name) &&
> -        !lookup_feature(kvm_features, flagname, NULL, kvm_feature_name) &&
> -        !lookup_feature(svm_features, flagname, NULL, svm_feature_name) &&
> -        !lookup_feature(cpuid_7_0_ebx_features, flagname, NULL,
> -                        cpuid_7_0_ebx_feature_name))
> -            fprintf(stderr, "CPU feature %s not found\n", flagname);
> -}
> -
>   typedef struct x86_def_t {
>       struct x86_def_t *next;
>       const char *name;
> @@ -1432,10 +1325,10 @@ static void cpudef_2_x86_cpu(X86CPU *cpu, x86_def_t *def, Error **errp)
>       object_property_set_int(OBJECT(cpu), (int64_t)def->tsc_khz * 1000,
>                               "tsc-frequency", errp);
>       env->cpuid_features = def->features;
> -    env->cpuid_ext_features = def->ext_features;
> +    env->cpuid_ext_features = (CPUID_EXT_HYPERVISOR & env->cpuid_ext_features) |
> +                              def->ext_features;
>       env->cpuid_ext2_features = def->ext2_features;
>       env->cpuid_ext3_features = def->ext3_features;
> -    env->cpuid_kvm_features = def->kvm_features;
>       env->cpuid_svm_features = def->svm_features;
>       env->cpuid_ext4_features = def->ext4_features;
>       env->cpuid_7_0_ebx_features = def->cpuid_7_0_ebx_features;
> @@ -1532,25 +1425,32 @@ out:
>       return;
>   }
>   
> +/* Set features on X86CPU object based on a QDict */
> +static void cpu_x86_set_props(X86CPU *cpu, QDict *features, Error **errp)
> +{
> +    const QDictEntry *ent;
> +
> +    for (ent = qdict_first(features); ent; ent = qdict_next(features, ent)) {
> +        const QString *qval = qobject_to_qstring(qdict_entry_value(ent));
> +        object_property_parse(OBJECT(cpu), qstring_get_str(qval),
> +                              qdict_entry_key(ent), errp);
> +        if (error_is_set(errp)) {
> +            return;
> +        }
> +    }
> +}
> +
>   static int cpu_x86_find_by_name(X86CPU *cpu, x86_def_t *x86_cpu_def,
>                                   const char *cpu_model, Error **errp)
>   {
>       x86_def_t *def;
> -    CPUX86State *env = &cpu->env;
> +    QDict *features = NULL;
> +    char *name = NULL;
>   
> -    char *s = g_strdup(cpu_model);
> -    char *featurestr, *name = strtok(s, ",");
> -    /* Features to be added*/
> -    uint32_t plus_features = 0, plus_ext_features = env->cpuid_ext_features;
> -    uint32_t plus_ext2_features = 0, plus_ext3_features = 0;
> -    uint32_t plus_kvm_features = env->cpuid_kvm_features, plus_svm_features = 0;
> -    uint32_t plus_7_0_ebx_features = 0;
> -    /* Features to be removed */
> -    uint32_t minus_features = 0, minus_ext_features = 0;
> -    uint32_t minus_ext2_features = 0, minus_ext3_features = 0;
> -    uint32_t minus_kvm_features = 0, minus_svm_features = 0;
> -    uint32_t minus_7_0_ebx_features = 0;
> -    uint32_t numvalue;
> +    compat_normalize_cpu_model(cpu_model, &name, &features, errp);
> +    if (error_is_set(errp)) {
> +        goto error;
> +    }
>   
>       for (def = x86_defs; def; def = def->next)
>           if (name && !strcmp(name, def->name))
> @@ -1563,127 +1463,18 @@ static int cpu_x86_find_by_name(X86CPU *cpu, x86_def_t *x86_cpu_def,
>           memcpy(x86_cpu_def, def, sizeof(*def));
>       }
>   
> -    featurestr = strtok(NULL, ",");
> -
> -    while (featurestr) {
> -        char *val;
> -        if (featurestr[0] == '+') {
> -            add_flagname_to_bitmaps(featurestr + 1, &plus_features,
> -                            &plus_ext_features, &plus_ext2_features,
> -                            &plus_ext3_features, &plus_kvm_features,
> -                            &plus_svm_features, &plus_7_0_ebx_features);
> -        } else if (featurestr[0] == '-') {
> -            add_flagname_to_bitmaps(featurestr + 1, &minus_features,
> -                            &minus_ext_features, &minus_ext2_features,
> -                            &minus_ext3_features, &minus_kvm_features,
> -                            &minus_svm_features, &minus_7_0_ebx_features);
> -        } else if ((val = strchr(featurestr, '='))) {
> -            *val = 0; val++;
> -            if (!strcmp(featurestr, "family")) {
> -                char *err;
> -                numvalue = strtoul(val, &err, 0);
> -                if (!*val || *err || numvalue > 0xff + 0xf) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                x86_cpu_def->family = numvalue;
> -            } else if (!strcmp(featurestr, "model")) {
> -                char *err;
> -                numvalue = strtoul(val, &err, 0);
> -                if (!*val || *err || numvalue > 0xff) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                x86_cpu_def->model = numvalue;
> -            } else if (!strcmp(featurestr, "stepping")) {
> -                char *err;
> -                numvalue = strtoul(val, &err, 0);
> -                if (!*val || *err || numvalue > 0xf) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                x86_cpu_def->stepping = numvalue ;
> -            } else if (!strcmp(featurestr, "level")) {
> -                char *err;
> -                numvalue = strtoul(val, &err, 0);
> -                if (!*val || *err) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                x86_cpu_def->level = numvalue;
> -            } else if (!strcmp(featurestr, "xlevel")) {
> -                char *err;
> -                numvalue = strtoul(val, &err, 0);
> -                if (!*val || *err) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                if (numvalue < 0x80000000) {
> -                    numvalue += 0x80000000;
> -                }
> -                x86_cpu_def->xlevel = numvalue;
> -            } else if (!strcmp(featurestr, "vendor")) {
> -                pstrcpy(x86_cpu_def->vendor, sizeof(x86_cpu_def->vendor), val);
> -                x86_cpu_def->vendor_override = 1;
> -            } else if (!strcmp(featurestr, "model_id")) {
This makes model_id= as a feature stop working.  It needs to be added to 
this patch, or maybe #10 where "tsc_freq" was handled.
> -                pstrcpy(x86_cpu_def->model_id, sizeof(x86_cpu_def->model_id),
> -                        val);
> -            } else if (!strcmp(featurestr, "tsc_freq")) {
> -                int64_t tsc_freq;
> -                char *err;
> -
> -                tsc_freq = strtosz_suffix_unit(val, &err,
> -                                               STRTOSZ_DEFSUFFIX_B, 1000);
> -                if (tsc_freq < 0 || *err) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                x86_cpu_def->tsc_khz = tsc_freq / 1000;
> -            } else if (!strcmp(featurestr, "hv_spinlocks")) {
> -                char *err;
> -                numvalue = strtoul(val, &err, 0);
> -                if (!*val || *err) {
> -                    fprintf(stderr, "bad numerical value %s\n", val);
> -                    goto error;
> -                }
> -                hyperv_set_spinlock_retries(numvalue);
> -            } else {
> -                fprintf(stderr, "unrecognized feature %s\n", featurestr);
> -                goto error;
> -            }
> -        } else if (!strcmp(featurestr, "check")) {
> -            check_cpuid = 1;
> -        } else if (!strcmp(featurestr, "enforce")) {
> -            check_cpuid = enforce_cpuid = 1;
> -        } else if (!strcmp(featurestr, "hv_relaxed")) {
> -            hyperv_enable_relaxed_timing(true);
> -        } else if (!strcmp(featurestr, "hv_vapic")) {
> -            hyperv_enable_vapic_recommended(true);
> -        } else {
> -            fprintf(stderr, "feature string `%s' not in format (+feature|-feature|feature=xyz)\n", featurestr);
> -            goto error;
> -        }
> -        featurestr = strtok(NULL, ",");
> +    cpu_x86_set_props(cpu, features, errp);
> +    if (error_is_set(errp)) {
> +        goto error;
>       }
> -    x86_cpu_def->features |= plus_features;
> -    x86_cpu_def->ext_features |= plus_ext_features;
> -    x86_cpu_def->ext2_features |= plus_ext2_features;
> -    x86_cpu_def->ext3_features |= plus_ext3_features;
> -    x86_cpu_def->kvm_features |= plus_kvm_features;
> -    x86_cpu_def->svm_features |= plus_svm_features;
> -    x86_cpu_def->cpuid_7_0_ebx_features |= plus_7_0_ebx_features;
> -    x86_cpu_def->features &= ~minus_features;
> -    x86_cpu_def->ext_features &= ~minus_ext_features;
> -    x86_cpu_def->ext2_features &= ~minus_ext2_features;
> -    x86_cpu_def->ext3_features &= ~minus_ext3_features;
> -    x86_cpu_def->kvm_features &= ~minus_kvm_features;
> -    x86_cpu_def->svm_features &= ~minus_svm_features;
> -    x86_cpu_def->cpuid_7_0_ebx_features &= ~minus_7_0_ebx_features;
> -    g_free(s);
> +
> +    g_free(name);
> +    QDECREF(features);
>       return 0;
>   
>   error:
> -    g_free(s);
> +    g_free(name);
> +    QDECREF(features);
>       if (!error_is_set(errp)) {
>           error_set(errp, QERR_INVALID_PARAMETER_COMBINATION);
>       }
    -Don Slutz