[PATCH 0/3][uq/master] Basic TSC-Scaling support v2

[PATCH 0/3][uq/master] Basic TSC-Scaling support v2

[Joerg Roedel]

Hi Avi, Marcelo,

here is v2 of the patches to support setting the guests tsc-frequency
from the qemu command line. This version addresses the comment from Avi
on the first version. To reflect that units can be given to the
frequency, the parameter was renamed from tsc_khz to tsc_freq.

Thanks,

	Joerg

Diffstat:

 cutils.c            |   16 +++++++++++-----
 qemu-common.h       |    2 ++
 target-i386/cpu.h   |    1 +
 target-i386/cpuid.c |   13 +++++++++++++
 target-i386/kvm.c   |   18 +++++++++++++++++-
 5 files changed, 44 insertions(+), 6 deletions(-)

[Qemu-devel] [PATCH 0/3][uq/master] Basic TSC-Scaling support v2

[Joerg Roedel]

Hi Avi, Marcelo,

here is v2 of the patches to support setting the guests tsc-frequency
from the qemu command line. This version addresses the comment from Avi
on the first version. To reflect that units can be given to the
frequency, the parameter was renamed from tsc_khz to tsc_freq.

Thanks,

	Joerg

Diffstat:

 cutils.c            |   16 +++++++++++-----
 qemu-common.h       |    2 ++
 target-i386/cpu.h   |    1 +
 target-i386/cpuid.c |   13 +++++++++++++
 target-i386/kvm.c   |   18 +++++++++++++++++-
 5 files changed, 44 insertions(+), 6 deletions(-)

[PATCH 1/3] qemu: Add strtosz_suffix_unit function

[Joerg Roedel]

This function does the same as the strtosz_suffix function
except that it allows to specify the unit to which the
k/M/B/T suffixes apply. This function will be used later to
parse the tsc-frequency from the command-line.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 cutils.c      |   16 +++++++++++-----
 qemu-common.h |    2 ++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/cutils.c b/cutils.c
index f9a7e36..28049e0 100644
--- a/cutils.c
+++ b/cutils.c
@@ -322,7 +322,8 @@ int fcntl_setfl(int fd, int flag)
  * value must be terminated by whitespace, ',' or '\0'. Return -1 on
  * error.
  */
-int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
+int64_t strtosz_suffix_unit(const char *nptr, char **end,
+                            const char default_suffix, int64_t unit)
 {
     int64_t retval = -1;
     char *endptr;
@@ -362,20 +363,20 @@ int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
         }
         break;
     case STRTOSZ_DEFSUFFIX_KB:
-        mul = 1 << 10;
+        mul = unit;
         break;
     case 0:
         if (mul_required) {
             goto fail;
         }
     case STRTOSZ_DEFSUFFIX_MB:
-        mul = 1ULL << 20;
+        mul = unit * unit;
         break;
     case STRTOSZ_DEFSUFFIX_GB:
-        mul = 1ULL << 30;
+        mul = unit * unit * unit;
         break;
     case STRTOSZ_DEFSUFFIX_TB:
-        mul = 1ULL << 40;
+        mul = unit * unit * unit * unit;
         break;
     default:
         goto fail;
@@ -405,6 +406,11 @@ fail:
     return retval;
 }
 
+int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
+{
+        return strtosz_suffix_unit(nptr, end, default_suffix, 1024);
+}
+
 int64_t strtosz(const char *nptr, char **end)
 {
     return strtosz_suffix(nptr, end, STRTOSZ_DEFSUFFIX_MB);
diff --git a/qemu-common.h b/qemu-common.h
index 109498d..854031a 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -186,6 +186,8 @@ int fcntl_setfl(int fd, int flag);
 #define STRTOSZ_DEFSUFFIX_B	'B'
 int64_t strtosz(const char *nptr, char **end);
 int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix);
+int64_t strtosz_suffix_unit(const char *nptr, char **end,
+                            const char default_suffix, int64_t unit);
 
 /* path.c */
 void init_paths(const char *prefix);
-- 
1.7.4.1

[Qemu-devel] [PATCH 1/3] qemu: Add strtosz_suffix_unit function

[Joerg Roedel]

This function does the same as the strtosz_suffix function
except that it allows to specify the unit to which the
k/M/B/T suffixes apply. This function will be used later to
parse the tsc-frequency from the command-line.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 cutils.c      |   16 +++++++++++-----
 qemu-common.h |    2 ++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/cutils.c b/cutils.c
index f9a7e36..28049e0 100644
--- a/cutils.c
+++ b/cutils.c
@@ -322,7 +322,8 @@ int fcntl_setfl(int fd, int flag)
  * value must be terminated by whitespace, ',' or '\0'. Return -1 on
  * error.
  */
-int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
+int64_t strtosz_suffix_unit(const char *nptr, char **end,
+                            const char default_suffix, int64_t unit)
 {
     int64_t retval = -1;
     char *endptr;
@@ -362,20 +363,20 @@ int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
         }
         break;
     case STRTOSZ_DEFSUFFIX_KB:
-        mul = 1 << 10;
+        mul = unit;
         break;
     case 0:
         if (mul_required) {
             goto fail;
         }
     case STRTOSZ_DEFSUFFIX_MB:
-        mul = 1ULL << 20;
+        mul = unit * unit;
         break;
     case STRTOSZ_DEFSUFFIX_GB:
-        mul = 1ULL << 30;
+        mul = unit * unit * unit;
         break;
     case STRTOSZ_DEFSUFFIX_TB:
-        mul = 1ULL << 40;
+        mul = unit * unit * unit * unit;
         break;
     default:
         goto fail;
@@ -405,6 +406,11 @@ fail:
     return retval;
 }
 
+int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
+{
+        return strtosz_suffix_unit(nptr, end, default_suffix, 1024);
+}
+
 int64_t strtosz(const char *nptr, char **end)
 {
     return strtosz_suffix(nptr, end, STRTOSZ_DEFSUFFIX_MB);
diff --git a/qemu-common.h b/qemu-common.h
index 109498d..854031a 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -186,6 +186,8 @@ int fcntl_setfl(int fd, int flag);
 #define STRTOSZ_DEFSUFFIX_B	'B'
 int64_t strtosz(const char *nptr, char **end);
 int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix);
+int64_t strtosz_suffix_unit(const char *nptr, char **end,
+                            const char default_suffix, int64_t unit);
 
 /* path.c */
 void init_paths(const char *prefix);
-- 
1.7.4.1

[PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Joerg Roedel]

To let the user configure the desired tsc frequency for the
guest if running in KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 target-i386/cpu.h   |    1 +
 target-i386/cpuid.c |   13 +++++++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index cdf68ff..399e124 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -743,6 +743,7 @@ typedef struct CPUX86State {
     uint32_t cpuid_kvm_features;
     uint32_t cpuid_svm_features;
     bool tsc_valid;
+    int tsc_khz;
     
     /* in order to simplify APIC support, we leave this pointer to the
        user */
diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
index e1ae3af..89e9623 100644
--- a/target-i386/cpuid.c
+++ b/target-i386/cpuid.c
@@ -224,6 +224,7 @@ typedef struct x86_def_t {
     int family;
     int model;
     int stepping;
+    int tsc_khz;
     uint32_t features, ext_features, ext2_features, ext3_features;
     uint32_t kvm_features, svm_features;
     uint32_t xlevel;
@@ -704,6 +705,17 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
             } else if (!strcmp(featurestr, "model_id")) {
                 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 (!*val || *err) {
+                    fprintf(stderr, "bad numerical value %s\n", val);
+                    goto error;
+                }
+                x86_cpu_def->tsc_khz = tsc_freq / 1000;
             } else {
                 fprintf(stderr, "unrecognized feature %s\n", featurestr);
                 goto error;
@@ -872,6 +884,7 @@ int cpu_x86_register (CPUX86State *env, const char *cpu_model)
     env->cpuid_svm_features = def->svm_features;
     env->cpuid_ext4_features = def->ext4_features;
     env->cpuid_xlevel2 = def->xlevel2;
+    env->tsc_khz = def->tsc_khz;
     if (!kvm_enabled()) {
         env->cpuid_features &= TCG_FEATURES;
         env->cpuid_ext_features &= TCG_EXT_FEATURES;
-- 
1.7.4.1

[Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Joerg Roedel]

To let the user configure the desired tsc frequency for the
guest if running in KVM.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 target-i386/cpu.h   |    1 +
 target-i386/cpuid.c |   13 +++++++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index cdf68ff..399e124 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -743,6 +743,7 @@ typedef struct CPUX86State {
     uint32_t cpuid_kvm_features;
     uint32_t cpuid_svm_features;
     bool tsc_valid;
+    int tsc_khz;
     
     /* in order to simplify APIC support, we leave this pointer to the
        user */
diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
index e1ae3af..89e9623 100644
--- a/target-i386/cpuid.c
+++ b/target-i386/cpuid.c
@@ -224,6 +224,7 @@ typedef struct x86_def_t {
     int family;
     int model;
     int stepping;
+    int tsc_khz;
     uint32_t features, ext_features, ext2_features, ext3_features;
     uint32_t kvm_features, svm_features;
     uint32_t xlevel;
@@ -704,6 +705,17 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
             } else if (!strcmp(featurestr, "model_id")) {
                 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 (!*val || *err) {
+                    fprintf(stderr, "bad numerical value %s\n", val);
+                    goto error;
+                }
+                x86_cpu_def->tsc_khz = tsc_freq / 1000;
             } else {
                 fprintf(stderr, "unrecognized feature %s\n", featurestr);
                 goto error;
@@ -872,6 +884,7 @@ int cpu_x86_register (CPUX86State *env, const char *cpu_model)
     env->cpuid_svm_features = def->svm_features;
     env->cpuid_ext4_features = def->ext4_features;
     env->cpuid_xlevel2 = def->xlevel2;
+    env->tsc_khz = def->tsc_khz;
     if (!kvm_enabled()) {
         env->cpuid_features &= TCG_FEATURES;
         env->cpuid_ext_features &= TCG_EXT_FEATURES;
-- 
1.7.4.1

[PATCH 3/3] qemu-x86: Set tsc_khz in kvm when supported

[Joerg Roedel]

Make use of the KVM_TSC_CONTROL feature if available.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 target-i386/kvm.c |   18 +++++++++++++++++-
 1 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 10fb2c4..923d2d5 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -354,6 +354,7 @@ int kvm_arch_init_vcpu(CPUState *env)
     uint32_t unused;
     struct kvm_cpuid_entry2 *c;
     uint32_t signature[3];
+    int r;
 
     env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
 
@@ -499,7 +500,22 @@ int kvm_arch_init_vcpu(CPUState *env)
 
     qemu_add_vm_change_state_handler(cpu_update_state, env);
 
-    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
+    r = kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
+    if (r)
+	    return r;
+
+#ifdef KVM_CAP_TSC_CONTROL
+    r = kvm_check_extension(env->kvm_state, KVM_CAP_TSC_CONTROL);
+    if (r && env->tsc_khz) {
+        r = kvm_vcpu_ioctl(env, KVM_SET_TSC_KHZ, env->tsc_khz);
+        if (r < 0) {
+            fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
+            return r;
+        }
+    }
+#endif
+
+    return 0;
 }
 
 void kvm_arch_reset_vcpu(CPUState *env)
-- 
1.7.4.1

[Qemu-devel] [PATCH 3/3] qemu-x86: Set tsc_khz in kvm when supported

[Joerg Roedel]

Make use of the KVM_TSC_CONTROL feature if available.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 target-i386/kvm.c |   18 +++++++++++++++++-
 1 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 10fb2c4..923d2d5 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -354,6 +354,7 @@ int kvm_arch_init_vcpu(CPUState *env)
     uint32_t unused;
     struct kvm_cpuid_entry2 *c;
     uint32_t signature[3];
+    int r;
 
     env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
 
@@ -499,7 +500,22 @@ int kvm_arch_init_vcpu(CPUState *env)
 
     qemu_add_vm_change_state_handler(cpu_update_state, env);
 
-    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
+    r = kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
+    if (r)
+	    return r;
+
+#ifdef KVM_CAP_TSC_CONTROL
+    r = kvm_check_extension(env->kvm_state, KVM_CAP_TSC_CONTROL);
+    if (r && env->tsc_khz) {
+        r = kvm_vcpu_ioctl(env, KVM_SET_TSC_KHZ, env->tsc_khz);
+        if (r < 0) {
+            fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
+            return r;
+        }
+    }
+#endif
+
+    return 0;
 }
 
 void kvm_arch_reset_vcpu(CPUState *env)
-- 
1.7.4.1

Re: [PATCH 1/3] qemu: Add strtosz_suffix_unit function

[Markus Armbruster]

Joerg Roedel <joerg.roedel@amd.com> writes:

> This function does the same as the strtosz_suffix function
> except that it allows to specify the unit to which the
> k/M/B/T suffixes apply. This function will be used later to
> parse the tsc-frequency from the command-line.
>
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  cutils.c      |   16 +++++++++++-----
>  qemu-common.h |    2 ++
>  2 files changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/cutils.c b/cutils.c
> index f9a7e36..28049e0 100644
> --- a/cutils.c
> +++ b/cutils.c
> @@ -322,7 +322,8 @@ int fcntl_setfl(int fd, int flag)
>   * value must be terminated by whitespace, ',' or '\0'. Return -1 on
>   * error.
>   */
> -int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
> +int64_t strtosz_suffix_unit(const char *nptr, char **end,
> +                            const char default_suffix, int64_t unit)
>  {
>      int64_t retval = -1;
>      char *endptr;
> @@ -362,20 +363,20 @@ int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
>          }
>          break;
>      case STRTOSZ_DEFSUFFIX_KB:
> -        mul = 1 << 10;
> +        mul = unit;
>          break;
>      case 0:
>          if (mul_required) {
>              goto fail;
>          }
>      case STRTOSZ_DEFSUFFIX_MB:
> -        mul = 1ULL << 20;
> +        mul = unit * unit;
>          break;
>      case STRTOSZ_DEFSUFFIX_GB:
> -        mul = 1ULL << 30;
> +        mul = unit * unit * unit;
>          break;
>      case STRTOSZ_DEFSUFFIX_TB:
> -        mul = 1ULL << 40;
> +        mul = unit * unit * unit * unit;
>          break;
>      default:
>          goto fail;
> @@ -405,6 +406,11 @@ fail:
>      return retval;
>  }

Why would anyone ever call this function with an unit argument other
than 1000 or 1024?

Without such a use case, I'd rather give strtosz_suffix() a flag
parameter to pick SI prefixes (multiples of 1000) vs. binary prefixes
(multiples of 1024).

[...]

Re: [Qemu-devel] [PATCH 1/3] qemu: Add strtosz_suffix_unit function

[Markus Armbruster]

Joerg Roedel <joerg.roedel@amd.com> writes:

> This function does the same as the strtosz_suffix function
> except that it allows to specify the unit to which the
> k/M/B/T suffixes apply. This function will be used later to
> parse the tsc-frequency from the command-line.
>
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  cutils.c      |   16 +++++++++++-----
>  qemu-common.h |    2 ++
>  2 files changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/cutils.c b/cutils.c
> index f9a7e36..28049e0 100644
> --- a/cutils.c
> +++ b/cutils.c
> @@ -322,7 +322,8 @@ int fcntl_setfl(int fd, int flag)
>   * value must be terminated by whitespace, ',' or '\0'. Return -1 on
>   * error.
>   */
> -int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
> +int64_t strtosz_suffix_unit(const char *nptr, char **end,
> +                            const char default_suffix, int64_t unit)
>  {
>      int64_t retval = -1;
>      char *endptr;
> @@ -362,20 +363,20 @@ int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
>          }
>          break;
>      case STRTOSZ_DEFSUFFIX_KB:
> -        mul = 1 << 10;
> +        mul = unit;
>          break;
>      case 0:
>          if (mul_required) {
>              goto fail;
>          }
>      case STRTOSZ_DEFSUFFIX_MB:
> -        mul = 1ULL << 20;
> +        mul = unit * unit;
>          break;
>      case STRTOSZ_DEFSUFFIX_GB:
> -        mul = 1ULL << 30;
> +        mul = unit * unit * unit;
>          break;
>      case STRTOSZ_DEFSUFFIX_TB:
> -        mul = 1ULL << 40;
> +        mul = unit * unit * unit * unit;
>          break;
>      default:
>          goto fail;
> @@ -405,6 +406,11 @@ fail:
>      return retval;
>  }

Why would anyone ever call this function with an unit argument other
than 1000 or 1024?

Without such a use case, I'd rather give strtosz_suffix() a flag
parameter to pick SI prefixes (multiples of 1000) vs. binary prefixes
(multiples of 1024).

[...]

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Marcelo Tosatti]

On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
> To let the user configure the desired tsc frequency for the
> guest if running in KVM.
> 
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  target-i386/cpu.h   |    1 +
>  target-i386/cpuid.c |   13 +++++++++++++
>  2 files changed, 14 insertions(+), 0 deletions(-)
> 
> diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> index cdf68ff..399e124 100644
> --- a/target-i386/cpu.h
> +++ b/target-i386/cpu.h
> @@ -743,6 +743,7 @@ typedef struct CPUX86State {
>      uint32_t cpuid_kvm_features;
>      uint32_t cpuid_svm_features;
>      bool tsc_valid;
> +    int tsc_khz;

This should be saved/restore in migration data (missing VMSTATE entry).

>      /* in order to simplify APIC support, we leave this pointer to the
>         user */
> diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
> index e1ae3af..89e9623 100644
> --- a/target-i386/cpuid.c
> +++ b/target-i386/cpuid.c
> @@ -224,6 +224,7 @@ typedef struct x86_def_t {
>      int family;
>      int model;
>      int stepping;
> +    int tsc_khz;
>      uint32_t features, ext_features, ext2_features, ext3_features;
>      uint32_t kvm_features, svm_features;
>      uint32_t xlevel;
> @@ -704,6 +705,17 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
>              } else if (!strcmp(featurestr, "model_id")) {
>                  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 (!*val || *err) {
> +                    fprintf(stderr, "bad numerical value %s\n", val);
> +                    goto error;
> +                }
> +                x86_cpu_def->tsc_khz = tsc_freq / 1000;
>              } else {
>                  fprintf(stderr, "unrecognized feature %s\n", featurestr);
>                  goto error;
> @@ -872,6 +884,7 @@ int cpu_x86_register (CPUX86State *env, const char *cpu_model)
>      env->cpuid_svm_features = def->svm_features;
>      env->cpuid_ext4_features = def->ext4_features;
>      env->cpuid_xlevel2 = def->xlevel2;
> +    env->tsc_khz = def->tsc_khz;
>      if (!kvm_enabled()) {
>          env->cpuid_features &= TCG_FEATURES;
>          env->cpuid_ext_features &= TCG_EXT_FEATURES;
> -- 
> 1.7.4.1
> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Marcelo Tosatti]

On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
> To let the user configure the desired tsc frequency for the
> guest if running in KVM.
> 
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  target-i386/cpu.h   |    1 +
>  target-i386/cpuid.c |   13 +++++++++++++
>  2 files changed, 14 insertions(+), 0 deletions(-)
> 
> diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> index cdf68ff..399e124 100644
> --- a/target-i386/cpu.h
> +++ b/target-i386/cpu.h
> @@ -743,6 +743,7 @@ typedef struct CPUX86State {
>      uint32_t cpuid_kvm_features;
>      uint32_t cpuid_svm_features;
>      bool tsc_valid;
> +    int tsc_khz;

This should be saved/restore in migration data (missing VMSTATE entry).

>      /* in order to simplify APIC support, we leave this pointer to the
>         user */
> diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
> index e1ae3af..89e9623 100644
> --- a/target-i386/cpuid.c
> +++ b/target-i386/cpuid.c
> @@ -224,6 +224,7 @@ typedef struct x86_def_t {
>      int family;
>      int model;
>      int stepping;
> +    int tsc_khz;
>      uint32_t features, ext_features, ext2_features, ext3_features;
>      uint32_t kvm_features, svm_features;
>      uint32_t xlevel;
> @@ -704,6 +705,17 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
>              } else if (!strcmp(featurestr, "model_id")) {
>                  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 (!*val || *err) {
> +                    fprintf(stderr, "bad numerical value %s\n", val);
> +                    goto error;
> +                }
> +                x86_cpu_def->tsc_khz = tsc_freq / 1000;
>              } else {
>                  fprintf(stderr, "unrecognized feature %s\n", featurestr);
>                  goto error;
> @@ -872,6 +884,7 @@ int cpu_x86_register (CPUX86State *env, const char *cpu_model)
>      env->cpuid_svm_features = def->svm_features;
>      env->cpuid_ext4_features = def->ext4_features;
>      env->cpuid_xlevel2 = def->xlevel2;
> +    env->tsc_khz = def->tsc_khz;
>      if (!kvm_enabled()) {
>          env->cpuid_features &= TCG_FEATURES;
>          env->cpuid_ext_features &= TCG_EXT_FEATURES;
> -- 
> 1.7.4.1
> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 3/3] qemu-x86: Set tsc_khz in kvm when supported

[Marcelo Tosatti]

On Thu, Jul 07, 2011 at 04:13:13PM +0200, Joerg Roedel wrote:
> Make use of the KVM_TSC_CONTROL feature if available.
> 
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  target-i386/kvm.c |   18 +++++++++++++++++-
>  1 files changed, 17 insertions(+), 1 deletions(-)
> 
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 10fb2c4..923d2d5 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -354,6 +354,7 @@ int kvm_arch_init_vcpu(CPUState *env)
>      uint32_t unused;
>      struct kvm_cpuid_entry2 *c;
>      uint32_t signature[3];
> +    int r;
>  
>      env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
>  
> @@ -499,7 +500,22 @@ int kvm_arch_init_vcpu(CPUState *env)
>  
>      qemu_add_vm_change_state_handler(cpu_update_state, env);
>  
> -    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
> +    r = kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
> +    if (r)
> +	    return r;
> +
> +#ifdef KVM_CAP_TSC_CONTROL
> +    r = kvm_check_extension(env->kvm_state, KVM_CAP_TSC_CONTROL);
> +    if (r && env->tsc_khz) {
> +        r = kvm_vcpu_ioctl(env, KVM_SET_TSC_KHZ, env->tsc_khz);
> +        if (r < 0) {
> +            fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
> +            return r;
> +        }
> +    }
> +#endif

And this should be moved to kvm_arch_put_registers, in case 
level == KVM_PUT_FULL_STATE.

Re: [Qemu-devel] [PATCH 3/3] qemu-x86: Set tsc_khz in kvm when supported

[Marcelo Tosatti]

On Thu, Jul 07, 2011 at 04:13:13PM +0200, Joerg Roedel wrote:
> Make use of the KVM_TSC_CONTROL feature if available.
> 
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  target-i386/kvm.c |   18 +++++++++++++++++-
>  1 files changed, 17 insertions(+), 1 deletions(-)
> 
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 10fb2c4..923d2d5 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -354,6 +354,7 @@ int kvm_arch_init_vcpu(CPUState *env)
>      uint32_t unused;
>      struct kvm_cpuid_entry2 *c;
>      uint32_t signature[3];
> +    int r;
>  
>      env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
>  
> @@ -499,7 +500,22 @@ int kvm_arch_init_vcpu(CPUState *env)
>  
>      qemu_add_vm_change_state_handler(cpu_update_state, env);
>  
> -    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
> +    r = kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
> +    if (r)
> +	    return r;
> +
> +#ifdef KVM_CAP_TSC_CONTROL
> +    r = kvm_check_extension(env->kvm_state, KVM_CAP_TSC_CONTROL);
> +    if (r && env->tsc_khz) {
> +        r = kvm_vcpu_ioctl(env, KVM_SET_TSC_KHZ, env->tsc_khz);
> +        if (r < 0) {
> +            fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
> +            return r;
> +        }
> +    }
> +#endif

And this should be moved to kvm_arch_put_registers, in case 
level == KVM_PUT_FULL_STATE.

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 02:46 PM, Marcelo Tosatti wrote:
> On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
> >  To let the user configure the desired tsc frequency for the
> >  guest if running in KVM.
> >
> >  Signed-off-by: Joerg Roedel<joerg.roedel@amd.com>
> >  ---
> >   target-i386/cpu.h   |    1 +
> >   target-i386/cpuid.c |   13 +++++++++++++
> >   2 files changed, 14 insertions(+), 0 deletions(-)
> >
> >  diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> >  index cdf68ff..399e124 100644
> >  --- a/target-i386/cpu.h
> >  +++ b/target-i386/cpu.h
> >  @@ -743,6 +743,7 @@ typedef struct CPUX86State {
> >       uint32_t cpuid_kvm_features;
> >       uint32_t cpuid_svm_features;
> >       bool tsc_valid;
> >  +    int tsc_khz;
>
> This should be saved/restore in migration data (missing VMSTATE entry).

Why?  It's static data.  Traditionally we only migrate runtime data.

(although we've been talking about starting a naked qemu and pushing all 
of the configuration from the source).

-- 
error compiling committee.c: too many arguments to function

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 02:46 PM, Marcelo Tosatti wrote:
> On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
> >  To let the user configure the desired tsc frequency for the
> >  guest if running in KVM.
> >
> >  Signed-off-by: Joerg Roedel<joerg.roedel@amd.com>
> >  ---
> >   target-i386/cpu.h   |    1 +
> >   target-i386/cpuid.c |   13 +++++++++++++
> >   2 files changed, 14 insertions(+), 0 deletions(-)
> >
> >  diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> >  index cdf68ff..399e124 100644
> >  --- a/target-i386/cpu.h
> >  +++ b/target-i386/cpu.h
> >  @@ -743,6 +743,7 @@ typedef struct CPUX86State {
> >       uint32_t cpuid_kvm_features;
> >       uint32_t cpuid_svm_features;
> >       bool tsc_valid;
> >  +    int tsc_khz;
>
> This should be saved/restore in migration data (missing VMSTATE entry).

Why?  It's static data.  Traditionally we only migrate runtime data.

(although we've been talking about starting a naked qemu and pushing all 
of the configuration from the source).

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Marcelo Tosatti]

On Tue, Jul 19, 2011 at 03:20:37PM +0300, Avi Kivity wrote:
> On 07/19/2011 02:46 PM, Marcelo Tosatti wrote:
> >On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
> >>  To let the user configure the desired tsc frequency for the
> >>  guest if running in KVM.
> >>
> >>  Signed-off-by: Joerg Roedel<joerg.roedel@amd.com>
> >>  ---
> >>   target-i386/cpu.h   |    1 +
> >>   target-i386/cpuid.c |   13 +++++++++++++
> >>   2 files changed, 14 insertions(+), 0 deletions(-)
> >>
> >>  diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> >>  index cdf68ff..399e124 100644
> >>  --- a/target-i386/cpu.h
> >>  +++ b/target-i386/cpu.h
> >>  @@ -743,6 +743,7 @@ typedef struct CPUX86State {
> >>       uint32_t cpuid_kvm_features;
> >>       uint32_t cpuid_svm_features;
> >>       bool tsc_valid;
> >>  +    int tsc_khz;
> >
> >This should be saved/restore in migration data (missing VMSTATE entry).
> 
> Why?  It's static data.  Traditionally we only migrate runtime data.
> 
> (although we've been talking about starting a naked qemu and pushing
> all of the configuration from the source).

Right.

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Marcelo Tosatti]

On Tue, Jul 19, 2011 at 03:20:37PM +0300, Avi Kivity wrote:
> On 07/19/2011 02:46 PM, Marcelo Tosatti wrote:
> >On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
> >>  To let the user configure the desired tsc frequency for the
> >>  guest if running in KVM.
> >>
> >>  Signed-off-by: Joerg Roedel<joerg.roedel@amd.com>
> >>  ---
> >>   target-i386/cpu.h   |    1 +
> >>   target-i386/cpuid.c |   13 +++++++++++++
> >>   2 files changed, 14 insertions(+), 0 deletions(-)
> >>
> >>  diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> >>  index cdf68ff..399e124 100644
> >>  --- a/target-i386/cpu.h
> >>  +++ b/target-i386/cpu.h
> >>  @@ -743,6 +743,7 @@ typedef struct CPUX86State {
> >>       uint32_t cpuid_kvm_features;
> >>       uint32_t cpuid_svm_features;
> >>       bool tsc_valid;
> >>  +    int tsc_khz;
> >
> >This should be saved/restore in migration data (missing VMSTATE entry).
> 
> Why?  It's static data.  Traditionally we only migrate runtime data.
> 
> (although we've been talking about starting a naked qemu and pushing
> all of the configuration from the source).

Right.

Re: [PATCH 0/3][uq/master] Basic TSC-Scaling support v2

[Marcelo Tosatti]

On Thu, Jul 07, 2011 at 04:13:10PM +0200, Joerg Roedel wrote:
> Hi Avi, Marcelo,
> 
> here is v2 of the patches to support setting the guests tsc-frequency
> from the qemu command line. This version addresses the comment from Avi
> on the first version. To reflect that units can be given to the
> frequency, the parameter was renamed from tsc_khz to tsc_freq.
> 
> Thanks,
> 
> 	Joerg

Applied to uq/master, thanks.

Re: [Qemu-devel] [PATCH 0/3][uq/master] Basic TSC-Scaling support v2

[Marcelo Tosatti]

On Thu, Jul 07, 2011 at 04:13:10PM +0200, Joerg Roedel wrote:
> Hi Avi, Marcelo,
> 
> here is v2 of the patches to support setting the guests tsc-frequency
> from the qemu command line. This version addresses the comment from Avi
> on the first version. To reflect that units can be given to the
> frequency, the parameter was renamed from tsc_khz to tsc_freq.
> 
> Thanks,
> 
> 	Joerg

Applied to uq/master, thanks.

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Joerg Roedel]

On Tue, Jul 19, 2011 at 03:20:37PM +0300, Avi Kivity wrote:
> On 07/19/2011 02:46 PM, Marcelo Tosatti wrote:
>> On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
>> >  To let the user configure the desired tsc frequency for the
>> >  guest if running in KVM.
>> >
>> >  Signed-off-by: Joerg Roedel<joerg.roedel@amd.com>
>> >  ---
>> >   target-i386/cpu.h   |    1 +
>> >   target-i386/cpuid.c |   13 +++++++++++++
>> >   2 files changed, 14 insertions(+), 0 deletions(-)
>> >
>> >  diff --git a/target-i386/cpu.h b/target-i386/cpu.h
>> >  index cdf68ff..399e124 100644
>> >  --- a/target-i386/cpu.h
>> >  +++ b/target-i386/cpu.h
>> >  @@ -743,6 +743,7 @@ typedef struct CPUX86State {
>> >       uint32_t cpuid_kvm_features;
>> >       uint32_t cpuid_svm_features;
>> >       bool tsc_valid;
>> >  +    int tsc_khz;
>>
>> This should be saved/restore in migration data (missing VMSTATE entry).
>
> Why?  It's static data.  Traditionally we only migrate runtime data.
>
> (although we've been talking about starting a naked qemu and pushing all  
> of the configuration from the source).

Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
hosts and migrate it over so that the destination host can set the
tsc-freq if it supports tsc-scaling.

	Joerg

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Joerg Roedel]

On Tue, Jul 19, 2011 at 03:20:37PM +0300, Avi Kivity wrote:
> On 07/19/2011 02:46 PM, Marcelo Tosatti wrote:
>> On Thu, Jul 07, 2011 at 04:13:12PM +0200, Joerg Roedel wrote:
>> >  To let the user configure the desired tsc frequency for the
>> >  guest if running in KVM.
>> >
>> >  Signed-off-by: Joerg Roedel<joerg.roedel@amd.com>
>> >  ---
>> >   target-i386/cpu.h   |    1 +
>> >   target-i386/cpuid.c |   13 +++++++++++++
>> >   2 files changed, 14 insertions(+), 0 deletions(-)
>> >
>> >  diff --git a/target-i386/cpu.h b/target-i386/cpu.h
>> >  index cdf68ff..399e124 100644
>> >  --- a/target-i386/cpu.h
>> >  +++ b/target-i386/cpu.h
>> >  @@ -743,6 +743,7 @@ typedef struct CPUX86State {
>> >       uint32_t cpuid_kvm_features;
>> >       uint32_t cpuid_svm_features;
>> >       bool tsc_valid;
>> >  +    int tsc_khz;
>>
>> This should be saved/restore in migration data (missing VMSTATE entry).
>
> Why?  It's static data.  Traditionally we only migrate runtime data.
>
> (although we've been talking about starting a naked qemu and pushing all  
> of the configuration from the source).

Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
hosts and migrate it over so that the destination host can set the
tsc-freq if it supports tsc-scaling.

	Joerg

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 04:30 PM, Joerg Roedel wrote:
> >
> >  (although we've been talking about starting a naked qemu and pushing all
> >  of the configuration from the source).
>
> Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
> plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
> hosts and migrate it over so that the destination host can set the
> tsc-freq if it supports tsc-scaling.

This can be done by a management tool if desired.

-- 
error compiling committee.c: too many arguments to function

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 04:30 PM, Joerg Roedel wrote:
> >
> >  (although we've been talking about starting a naked qemu and pushing all
> >  of the configuration from the source).
>
> Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
> plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
> hosts and migrate it over so that the destination host can set the
> tsc-freq if it supports tsc-scaling.

This can be done by a management tool if desired.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 04:54 PM, Avi Kivity wrote:
> On 07/19/2011 04:30 PM, Joerg Roedel wrote:
>> >
>> >  (although we've been talking about starting a naked qemu and 
>> pushing all
>> >  of the configuration from the source).
>>
>> Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
>> plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
>> hosts and migrate it over so that the destination host can set the
>> tsc-freq if it supports tsc-scaling.
>
> This can be done by a management tool if desired.
>

Although, if we do this unconditionally (that is, also for tsc-scale 
hosts) then we get stable tsc even without supplying a tsc frequency 
argument... need to think about this.

-- 
error compiling committee.c: too many arguments to function

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 04:54 PM, Avi Kivity wrote:
> On 07/19/2011 04:30 PM, Joerg Roedel wrote:
>> >
>> >  (although we've been talking about starting a naked qemu and 
>> pushing all
>> >  of the configuration from the source).
>>
>> Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
>> plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
>> hosts and migrate it over so that the destination host can set the
>> tsc-freq if it supports tsc-scaling.
>
> This can be done by a management tool if desired.
>

Although, if we do this unconditionally (that is, also for tsc-scale 
hosts) then we get stable tsc even without supplying a tsc frequency 
argument... need to think about this.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Joerg Roedel]

On Tue, Jul 19, 2011 at 04:55:53PM +0300, Avi Kivity wrote:
> On 07/19/2011 04:54 PM, Avi Kivity wrote:
>> On 07/19/2011 04:30 PM, Joerg Roedel wrote:

>>> Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
>>> plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
>>> hosts and migrate it over so that the destination host can set the
>>> tsc-freq if it supports tsc-scaling.
>>
>> This can be done by a management tool if desired.
>>
>
> Although, if we do this unconditionally (that is, also for tsc-scale  
> hosts) then we get stable tsc even without supplying a tsc frequency  
> argument... need to think about this.

It has the advantage that it "just works", without the need to extend
management tools and the like. And it makes migration more transparent
to the guests.

	Joerg

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Joerg Roedel]

On Tue, Jul 19, 2011 at 04:55:53PM +0300, Avi Kivity wrote:
> On 07/19/2011 04:54 PM, Avi Kivity wrote:
>> On 07/19/2011 04:30 PM, Joerg Roedel wrote:

>>> Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
>>> plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
>>> hosts and migrate it over so that the destination host can set the
>>> tsc-freq if it supports tsc-scaling.
>>
>> This can be done by a management tool if desired.
>>
>
> Although, if we do this unconditionally (that is, also for tsc-scale  
> hosts) then we get stable tsc even without supplying a tsc frequency  
> argument... need to think about this.

It has the advantage that it "just works", without the need to extend
management tools and the like. And it makes migration more transparent
to the guests.

	Joerg

Re: [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 05:14 PM, Joerg Roedel wrote:
> On Tue, Jul 19, 2011 at 04:55:53PM +0300, Avi Kivity wrote:
> >  On 07/19/2011 04:54 PM, Avi Kivity wrote:
> >>  On 07/19/2011 04:30 PM, Joerg Roedel wrote:
>
> >>>  Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
> >>>  plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
> >>>  hosts and migrate it over so that the destination host can set the
> >>>  tsc-freq if it supports tsc-scaling.
> >>
> >>  This can be done by a management tool if desired.
> >>
> >
> >  Although, if we do this unconditionally (that is, also for tsc-scale
> >  hosts) then we get stable tsc even without supplying a tsc frequency
> >  argument... need to think about this.
>
> It has the advantage that it "just works", without the need to extend
> management tools and the like. And it makes migration more transparent
> to the guests.
>

Yes, exactly.  The flip side is that automagic stuff is sometimes 
unexpected and leads to breakage.  I'm not sure what the right thing is.

-- 
error compiling committee.c: too many arguments to function

Re: [Qemu-devel] [PATCH 2/3] qemu-x86: Add tsc_freq option to -cpu

[Avi Kivity]

On 07/19/2011 05:14 PM, Joerg Roedel wrote:
> On Tue, Jul 19, 2011 at 04:55:53PM +0300, Avi Kivity wrote:
> >  On 07/19/2011 04:54 PM, Avi Kivity wrote:
> >>  On 07/19/2011 04:30 PM, Joerg Roedel wrote:
>
> >>>  Hmm, I planned to do the VMSTATE thing in a follow-on patch-set. The
> >>>  plan is to read the VCPU tsc_freq at guest start time on !tsc-scale
> >>>  hosts and migrate it over so that the destination host can set the
> >>>  tsc-freq if it supports tsc-scaling.
> >>
> >>  This can be done by a management tool if desired.
> >>
> >
> >  Although, if we do this unconditionally (that is, also for tsc-scale
> >  hosts) then we get stable tsc even without supplying a tsc frequency
> >  argument... need to think about this.
>
> It has the advantage that it "just works", without the need to extend
> management tools and the like. And it makes migration more transparent
> to the guests.
>

Yes, exactly.  The flip side is that automagic stuff is sometimes 
unexpected and leads to breakage.  I'm not sure what the right thing is.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH 3/3] qemu-x86: Set tsc_khz in kvm when supported

[Jan Kiszka]

On 2011-07-19 13:48, Marcelo Tosatti wrote:
> On Thu, Jul 07, 2011 at 04:13:13PM +0200, Joerg Roedel wrote:
>> Make use of the KVM_TSC_CONTROL feature if available.
>>
>> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
>> ---
>>  target-i386/kvm.c |   18 +++++++++++++++++-
>>  1 files changed, 17 insertions(+), 1 deletions(-)
>>
>> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
>> index 10fb2c4..923d2d5 100644
>> --- a/target-i386/kvm.c
>> +++ b/target-i386/kvm.c
>> @@ -354,6 +354,7 @@ int kvm_arch_init_vcpu(CPUState *env)
>>      uint32_t unused;
>>      struct kvm_cpuid_entry2 *c;
>>      uint32_t signature[3];
>> +    int r;
>>  
>>      env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
>>  
>> @@ -499,7 +500,22 @@ int kvm_arch_init_vcpu(CPUState *env)
>>  
>>      qemu_add_vm_change_state_handler(cpu_update_state, env);
>>  
>> -    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
>> +    r = kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
>> +    if (r)
>> +	    return r;
>> +
>> +#ifdef KVM_CAP_TSC_CONTROL
>> +    r = kvm_check_extension(env->kvm_state, KVM_CAP_TSC_CONTROL);
>> +    if (r && env->tsc_khz) {
>> +        r = kvm_vcpu_ioctl(env, KVM_SET_TSC_KHZ, env->tsc_khz);
>> +        if (r < 0) {
>> +            fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
>> +            return r;
>> +        }
>> +    }
>> +#endif
> 

#ifdef times are over, please clean up before pushing upstream.

Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux

Re: [Qemu-devel] [PATCH 3/3] qemu-x86: Set tsc_khz in kvm when supported

[Jan Kiszka]

On 2011-07-19 13:48, Marcelo Tosatti wrote:
> On Thu, Jul 07, 2011 at 04:13:13PM +0200, Joerg Roedel wrote:
>> Make use of the KVM_TSC_CONTROL feature if available.
>>
>> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
>> ---
>>  target-i386/kvm.c |   18 +++++++++++++++++-
>>  1 files changed, 17 insertions(+), 1 deletions(-)
>>
>> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
>> index 10fb2c4..923d2d5 100644
>> --- a/target-i386/kvm.c
>> +++ b/target-i386/kvm.c
>> @@ -354,6 +354,7 @@ int kvm_arch_init_vcpu(CPUState *env)
>>      uint32_t unused;
>>      struct kvm_cpuid_entry2 *c;
>>      uint32_t signature[3];
>> +    int r;
>>  
>>      env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
>>  
>> @@ -499,7 +500,22 @@ int kvm_arch_init_vcpu(CPUState *env)
>>  
>>      qemu_add_vm_change_state_handler(cpu_update_state, env);
>>  
>> -    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
>> +    r = kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
>> +    if (r)
>> +	    return r;
>> +
>> +#ifdef KVM_CAP_TSC_CONTROL
>> +    r = kvm_check_extension(env->kvm_state, KVM_CAP_TSC_CONTROL);
>> +    if (r && env->tsc_khz) {
>> +        r = kvm_vcpu_ioctl(env, KVM_SET_TSC_KHZ, env->tsc_khz);
>> +        if (r < 0) {
>> +            fprintf(stderr, "KVM_SET_TSC_KHZ failed\n");
>> +            return r;
>> +        }
>> +    }
>> +#endif
> 

#ifdef times are over, please clean up before pushing upstream.

Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux