[PATCH 2/5] KVM: selftests: Use generic sys_clocksource_is_tsc() in vmx_nested_tsc_scaling_test

From: Vitaly Kuznetsov
Date: Tue Jan 09 2024 - 09:12:24 EST


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@xxxxxxxxxx>
---
.../kvm/x86_64/vmx_nested_tsc_scaling_test.c | 19 +------------------
1 file changed, 1 insertion(+), 18 deletions(-)

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 e710b6e7fb38..93b0a850a240 100644
--- 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.
--
2.43.0