diff options
| -rw-r--r-- | tools/testing/selftests/kvm/access_tracking_perf_test.c | 62 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/include/test_util.h | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/lib/test_util.c | 7 |
3 files changed, 61 insertions, 9 deletions
diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c index 447e619cf856..f273e4a33b11 100644 --- a/tools/testing/selftests/kvm/access_tracking_perf_test.c +++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c @@ -65,6 +65,16 @@ static int vcpu_last_completed_iteration[KVM_MAX_VCPUS]; /* Whether to overlap the regions of memory vCPUs access. */ static bool overlap_memory_access; +/* + * If the test should only warn if there are too many idle pages (i.e., it is + * expected). + * -1: Not yet set. + * 0: We do not expect too many idle pages, so FAIL if too many idle pages. + * 1: Having too many idle pages is expected, so merely print a warning if + * too many idle pages are found. + */ +static int idle_pages_warn_only = -1; + struct test_params { /* The backing source for the region of memory. */ enum vm_mem_backing_src_type backing_src; @@ -177,18 +187,12 @@ static void mark_vcpu_memory_idle(struct kvm_vm *vm, * arbitrary; high enough that we ensure most memory access went through * access tracking but low enough as to not make the test too brittle * over time and across architectures. - * - * 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) { -#ifdef __x86_64__ - TEST_ASSERT(this_cpu_has(X86_FEATURE_HYPERVISOR), + TEST_ASSERT(idle_pages_warn_only, "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); @@ -328,6 +332,32 @@ static void run_test(enum vm_guest_mode mode, void *arg) memstress_destroy_vm(vm); } +static int access_tracking_unreliable(void) +{ +#ifdef __x86_64__ + /* + * When running nested, the TLB size may be effectively unlimited (for + * example, this is the case when running on KVM L0), and 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 (this_cpu_has(X86_FEATURE_HYPERVISOR)) { + puts("Skipping idle page count sanity check, because the test is run nested"); + return 1; + } +#endif + /* + * When NUMA balancing is enabled, guest memory will be unmapped to get + * NUMA faults, dropping the Accessed bits. + */ + if (is_numa_balancing_enabled()) { + puts("Skipping idle page count sanity check, because NUMA balancing is enabled"); + return 1; + } + + return 0; +} + static void help(char *name) { puts(""); @@ -342,6 +372,12 @@ static void help(char *name) printf(" -v: specify the number of vCPUs to run.\n"); printf(" -o: Overlap guest memory accesses instead of partitioning\n" " them into a separate region of memory for each vCPU.\n"); + printf(" -w: Control whether the test warns or fails if more than 10%%\n" + " of pages are still seen as idle/old after accessing guest\n" + " memory. >0 == warn only, 0 == fail, <0 == auto. For auto\n" + " mode, the test fails by default, but switches to warn only\n" + " if NUMA balancing is enabled or the test detects it's running\n" + " in a VM.\n"); backing_src_help("-s"); puts(""); exit(0); @@ -359,7 +395,7 @@ int main(int argc, char *argv[]) guest_modes_append_default(); - while ((opt = getopt(argc, argv, "hm:b:v:os:")) != -1) { + while ((opt = getopt(argc, argv, "hm:b:v:os:w:")) != -1) { switch (opt) { case 'm': guest_modes_cmdline(optarg); @@ -376,6 +412,11 @@ int main(int argc, char *argv[]) case 's': params.backing_src = parse_backing_src_type(optarg); break; + case 'w': + idle_pages_warn_only = + atoi_non_negative("Idle pages warning", + optarg); + break; case 'h': default: help(argv[0]); @@ -388,6 +429,9 @@ int main(int argc, char *argv[]) "CONFIG_IDLE_PAGE_TRACKING is not enabled"); close(page_idle_fd); + if (idle_pages_warn_only == -1) + idle_pages_warn_only = access_tracking_unreliable(); + for_each_guest_mode(run_test, ¶ms); return 0; diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h index 77d13d7920cb..c6ef895fbd9a 100644 --- a/tools/testing/selftests/kvm/include/test_util.h +++ b/tools/testing/selftests/kvm/include/test_util.h @@ -153,6 +153,7 @@ bool is_backing_src_hugetlb(uint32_t i); void backing_src_help(const char *flag); enum vm_mem_backing_src_type parse_backing_src_type(const char *type_name); long get_run_delay(void); +bool is_numa_balancing_enabled(void); /* * Whether or not the given source type is shared memory (as opposed to diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index 3dc8538f5d69..03eb99af9b8d 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -176,6 +176,13 @@ size_t get_trans_hugepagesz(void) return get_sysfs_val("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size"); } +bool is_numa_balancing_enabled(void) +{ + if (!test_sysfs_path("/proc/sys/kernel/numa_balancing")) + return false; + return get_sysfs_val("/proc/sys/kernel/numa_balancing") == 1; +} + size_t get_def_hugetlb_pagesz(void) { char buf[64]; |