It's only used to override the existing dirty ring size/count. If with a bigger ring count, we test async of dirty ring. If with a smaller ring count, we test ring full code path. It has no use for non-dirty-ring tests. Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> --- tools/testing/selftests/kvm/dirty_log_test.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c index 4799db91e919..c9db136a1f12 100644 --- a/tools/testing/selftests/kvm/dirty_log_test.c +++ b/tools/testing/selftests/kvm/dirty_log_test.c @@ -157,6 +157,7 @@ enum log_mode_t { /* Mode of logging. Default is LOG_MODE_DIRTY_LOG */ static enum log_mode_t host_log_mode; pthread_t vcpu_thread; +static uint32_t test_dirty_ring_count = TEST_DIRTY_RING_COUNT; /* Only way to pass this to the signal handler */ struct kvm_vm *current_vm; @@ -216,7 +217,7 @@ static void dirty_ring_create_vm_done(struct kvm_vm *vm) * Switch to dirty ring mode after VM creation but before any * of the vcpu creation. */ - vm_enable_dirty_ring(vm, TEST_DIRTY_RING_COUNT * + vm_enable_dirty_ring(vm, test_dirty_ring_count * sizeof(struct kvm_dirty_gfn)); } @@ -658,6 +659,9 @@ static void help(char *name) printf("usage: %s [-h] [-i iterations] [-I interval] " "[-p offset] [-m mode]\n", name); puts(""); + printf(" -c: specify dirty ring size, in number of entries\n"); + printf(" (only useful for dirty-ring test; default: %"PRIu32")\n", + TEST_DIRTY_RING_COUNT); printf(" -i: specify iteration counts (default: %"PRIu64")\n", TEST_HOST_LOOP_N); printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n", @@ -713,8 +717,11 @@ int main(int argc, char *argv[]) vm_guest_mode_params_init(VM_MODE_P40V48_4K, true, true); #endif - while ((opt = getopt(argc, argv, "hi:I:p:m:M:")) != -1) { + while ((opt = getopt(argc, argv, "c:hi:I:p:m:M:")) != -1) { switch (opt) { + case 'c': + test_dirty_ring_count = strtol(optarg, NULL, 10); + break; case 'i': iterations = strtol(optarg, NULL, 10); break; -- 2.21.0