diff options
Diffstat (limited to 'tools/testing/selftests/kvm/access_tracking_perf_test.c')
| -rw-r--r-- | tools/testing/selftests/kvm/access_tracking_perf_test.c | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c index 57a16371e9c2..3c7defd34f56 100644 --- a/tools/testing/selftests/kvm/access_tracking_perf_test.c +++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c @@ -46,6 +46,7 @@ #include "test_util.h" #include "memstress.h" #include "guest_modes.h" +#include "processor.h" /* Global variable used to synchronize all of the vCPU threads. */ static int iteration; @@ -177,16 +178,21 @@ static void mark_vcpu_memory_idle(struct kvm_vm *vm, * access tracking but low enough as to not make the test too brittle * over time and across architectures. * - * Note that when run in nested virtualization, this check will trigger - * much more frequently because TLB size is unlimited and since no flush - * happens, much more pages are cached there and guest won't see the - * "idle" bit cleared. + * When running the guest as a nested VM, "warn" instead of asserting + * as the TLB size is effectively unlimited and the KVM doesn't + * explicitly flush the TLB when aging SPTEs. As a result, more pages + * are cached and the guest won't see the "idle" bit cleared. */ - if (still_idle < pages / 10) - printf("WARNING: vCPU%d: Too many pages still idle (%" PRIu64 - "out of %" PRIu64 "), this will affect performance results" - ".\n", + if (still_idle >= pages / 10) { +#ifdef __x86_64__ + TEST_ASSERT(this_cpu_has(X86_FEATURE_HYPERVISOR), + "vCPU%d: Too many pages still idle (%lu out of %lu)", + vcpu_idx, still_idle, pages); +#endif + printf("WARNING: vCPU%d: Too many pages still idle (%lu out of %lu), " + "this will affect performance results.\n", vcpu_idx, still_idle, pages); + } close(page_idle_fd); close(pagemap_fd); |