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x86/xen: use capabilities instead of fake cpuid values for aperf

When running as pv domain xen_cpuid() is being used instead of
native_cpuid(). In xen_cpuid() the aperf/mperf feature is indicated
as not being present by special casing the related cpuid leaf.

Instead of delivering fake cpuid values clear the cpu capability bit
for aperf/mperf instead.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Juergen Gross 8 years ago
parent
commit
fd9145fd27
1 changed files with 1 additions and 8 deletions
  1. 1 8
      arch/x86/xen/enlighten_pv.c

+ 1 - 8
arch/x86/xen/enlighten_pv.c

@@ -165,9 +165,6 @@ xen_running_on_version_or_later(unsigned int major, unsigned int minor)
 	return false;
 }
 
-#define CPUID_THERM_POWER_LEAF 6
-#define APERFMPERF_PRESENT 0
-
 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
 
@@ -201,11 +198,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 		*dx = cpuid_leaf5_edx_val;
 		return;
 
-	case CPUID_THERM_POWER_LEAF:
-		/* Disabling APERFMPERF for kernel usage */
-		maskecx = ~(1 << APERFMPERF_PRESENT);
-		break;
-
 	case 0xb:
 		/* Suppress extended topology stuff */
 		maskebx = 0;
@@ -332,6 +324,7 @@ static void __init xen_init_capabilities(void)
 	setup_clear_cpu_cap(X86_BUG_SYSRET_SS_ATTRS);
 	setup_force_cpu_cap(X86_FEATURE_XENPV);
 	setup_clear_cpu_cap(X86_FEATURE_DCA);
+	setup_clear_cpu_cap(X86_FEATURE_APERFMPERF);
 }
 
 static void xen_set_debugreg(int reg, unsigned long val)