[PATCH v2 09/11] KVM: Expose the architectural performance monitoring CPUID leaf

[Avi Kivity <avi@redhat.com>]

Provide a CPUID leaf that describes the emulated PMU.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/x86.c |   20 +++++++++++++++++++-
 1 files changed, 19 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7bc5e56..7e1a02b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2442,6 +2442,25 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 	}
 	case 9:
 		break;
+	case 0xA: { /* Architectural Performance Monitoring */
+		unsigned version = entry->eax & 0xff;
+		unsigned gp_nr = (entry->eax >> 8) & 0xff;
+		unsigned gp_width = (entry->eax >> 16) & 0xff;
+
+		if (version < 1) {
+			gp_nr = 2;
+			gp_width = 40;
+		}
+
+		entry->eax = 0x01             /* version */
+			| (gp_nr << 8)
+			| (gp_width << 16)
+			| (7 << 24);   /* supported counters bitmask length */
+		entry->ebx &= (1 << 7) - 1;
+		entry->ecx = 0;
+		entry->edx = 0;
+		break;
+	}
 	/* function 0xb has additional index. */
 	case 0xb: {
 		int i, level_type;
@@ -2532,7 +2551,6 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 	case 3: /* Processor serial number */
 	case 5: /* MONITOR/MWAIT */
 	case 6: /* Thermal management */
-	case 0xA: /* Architectural Performance Monitoring */
 	case 0x80000007: /* Advanced power management */
 	case 0xC0000002:
 	case 0xC0000003:
-- 
1.7.5.3