Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
lib/x86/processor.h | 16 ++++++++++++++++
x86/tsc.c | 23 +++++++++++++++++++++++
x86/unittests.cfg | 1 +
3 files changed, 40 insertions(+)
diff --git a/lib/x86/processor.h b/lib/x86/processor.h
index 7973879..b9cb753 100644
--- a/lib/x86/processor.h
+++ b/lib/x86/processor.h
@@ -2,6 +2,7 @@
#define LIBCFLAT_PROCESSOR_H
#include "libcflat.h"
+#include "msr.h"
#include <stdint.h>
#ifdef __x86_64__
@@ -340,6 +341,21 @@ static inline unsigned long long rdtsc()
return r;
}
+static inline unsigned long long rdtscp(u32 *aux)
+{
+ long long r;
+
+#ifdef __x86_64__
+ unsigned a, d;
+
+ asm volatile ("rdtscp" : "=a"(a), "=d"(d), "=c"(*aux));
+ r = a | ((long long)d << 32);
+#else
+ asm volatile ("rdtscp" : "=A"(r), "=c"(*aux));
+#endif
+ return r;
+}
+
static inline void wrtsc(u64 tsc)
{
unsigned a = tsc, d = tsc >> 32;
diff --git a/x86/tsc.c b/x86/tsc.c
index 58f332d..c71dc2a 100644
--- a/x86/tsc.c
+++ b/x86/tsc.c
@@ -1,6 +1,13 @@
#include "libcflat.h"
#include "processor.h"
+#define CPUID_80000001_EDX_RDTSCP (1 << 27)
+int check_cpuid_80000001_edx(unsigned int bit)
+{
+ return (cpuid(0x80000001).d & bit) != 0;
+}
+
+
void test_wrtsc(u64 t1)
{
u64 t2;
@@ -10,6 +17,15 @@ void test_wrtsc(u64 t1)
printf("rdtsc after wrtsc(%lld): %lld\n", t1, t2);
}
+void test_rdtscp(u64 aux)
+{
+ u32 ecx;
+
+ wrmsr(MSR_TSC_AUX, aux);
+ rdtscp(&ecx);
+ report("Test RDTSCP %d", ecx == aux, aux);
+}
+
int main()
{
u64 t1, t2;
@@ -20,5 +36,12 @@ int main()
test_wrtsc(0);
test_wrtsc(100000000000ull);
+
+ if (check_cpuid_80000001_edx(CPUID_80000001_EDX_RDTSCP)) {
+ test_rdtscp(0);
+ test_rdtscp(10);
+ test_rdtscp(0x100);
+ } else
+ printf("rdtscp not supported\n");
return 0;
}
diff --git a/x86/unittests.cfg b/x86/unittests.cfg
index ac652fc..fd7e9b2 100644
--- a/x86/unittests.cfg
+++ b/x86/unittests.cfg
@@ -114,6 +114,7 @@ file = sieve.flat
[tsc]
file = tsc.flat
+extra_params = -cpu kvm64,+rdtscp
[tsc_adjust]
file = tsc_adjust.flat
--
2.5.0
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