KVM: selftests: Use generic sys_clocksource_is_tsc() in vmx_nested_tsc_scaling_test

Despite its name, system_has_stable_tsc() just checks that system
clocksource is 'tsc'; this can now be done with generic
sys_clocksource_is_tsc().

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240109141121.1619463-3-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c b/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c
index e710b6e7fb384aac124ad0c7f646a872b347ad51..93b0a850a2400326c5b2ee40f0a0a87d109aaf5c 100644 (file)
--- a/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c
@@ -116,23 +116,6 @@ static void l1_guest_code(struct vmx_pages *vmx_pages)
        GUEST_DONE();
 }
 
-static bool system_has_stable_tsc(void)
-{
-       bool tsc_is_stable;
-       FILE *fp;
-       char buf[4];
-
-       fp = fopen("/sys/devices/system/clocksource/clocksource0/current_clocksource", "r");
-       if (fp == NULL)
-               return false;
-
-       tsc_is_stable = fgets(buf, sizeof(buf), fp) &&
-                       !strncmp(buf, "tsc", sizeof(buf));
-
-       fclose(fp);
-       return tsc_is_stable;
-}
-
 int main(int argc, char *argv[])
 {
        struct kvm_vcpu *vcpu;
@@ -148,7 +131,7 @@ int main(int argc, char *argv[])
 
        TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
        TEST_REQUIRE(kvm_has_cap(KVM_CAP_TSC_CONTROL));
-       TEST_REQUIRE(system_has_stable_tsc());
+       TEST_REQUIRE(sys_clocksource_is_tsc());
 
        /*
         * We set L1's scale factor to be a random number from 2 to 10.