x86/xen: use capabilities instead of fake cpuid values for aperf
authorJuergen Gross <jgross@suse.com>
Wed, 12 Apr 2017 06:27:07 +0000 (08:27 +0200)
committerJuergen Gross <jgross@suse.com>
Tue, 2 May 2017 09:13:42 +0000 (11:13 +0200)
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>
arch/x86/xen/enlighten_pv.c

index bd69868909b4eb8dbd030eaaea82240950528029..4c8cd7278189d59bcd1813b2047a355251efd00c 100644 (file)
@@ -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)