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Date: Thu, 13 Apr 2017 12:11:08 +0200 From: Juergen Gross <jgross@...e.com> To: linux-kernel@...r.kernel.org, xen-devel@...ts.xenproject.org Cc: boris.ostrovsky@...cle.com, Juergen Gross <jgross@...e.com> Subject: [PATCH v2 03/11] 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@...e.com> --- arch/x86/xen/enlighten_pv.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index bd69868909b4..4c8cd7278189 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/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) -- 2.12.0
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