Create the ability to randomize page access order with the -a
argument, including the possibility that the same pages may be hit
multiple times during an iteration or not at all.
Signed-off-by: Colton Lewis <coltonlewis@xxxxxxxxxx>
---
.../testing/selftests/kvm/dirty_log_perf_test.c | 12 ++++++++++--
.../selftests/kvm/include/perf_test_util.h | 2 ++
tools/testing/selftests/kvm/lib/perf_test_util.c | 16 +++++++++++++++-
3 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
index c9441f8354be..631b3883ed12 100644
--- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
@@ -127,6 +127,7 @@ struct test_params {
int slots;
uint32_t write_percent;
uint32_t random_seed;
+ bool random_access;
};
static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable)
@@ -269,6 +270,9 @@ static void run_test(enum vm_guest_mode mode, void *arg)
pr_info("Enabling dirty logging time: %ld.%.9lds\n\n",
ts_diff.tv_sec, ts_diff.tv_nsec);
+ /* Set random access here, after population phase. */
+ perf_test_set_random_access(vm, p->random_access);
+
while (iteration < p->iterations) {
/*
* Incrementing the iteration number will start the vCPUs
@@ -339,10 +343,11 @@ static void run_test(enum vm_guest_mode mode, void *arg)
static void help(char *name)
{
puts("");
- printf("usage: %s [-h] [-i iterations] [-p offset] [-g] "
+ printf("usage: %s [-h] [-a] [-i iterations] [-p offset] [-g] "
"[-m mode] [-n] [-b vcpu bytes] [-v vcpus] [-o] [-r random seed ] [-s mem type]"
"[-x memslots] [-w percentage]\n", name);
puts("");
+ printf(" -a: access memory randomly rather than in order.\n");
printf(" -i: specify iteration counts (default: %"PRIu64")\n",
TEST_HOST_LOOP_N);
printf(" -g: Do not enable KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2. This\n"
@@ -394,8 +399,11 @@ int main(int argc, char *argv[])
guest_modes_append_default();
- while ((opt = getopt(argc, argv, "ghi:p:m:nb:v:or:s:x:w:")) != -1) {
+ while ((opt = getopt(argc, argv, "aghi:p:m:nb:v:or:s:x:w:")) != -1) {
switch (opt) {
+ case 'a':
+ p.random_access = true;
+ break;
case 'g':
dirty_log_manual_caps = 0;
break;
diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h
index 52c450eb6b9b..380c31375b60 100644
--- a/tools/testing/selftests/kvm/include/perf_test_util.h
+++ b/tools/testing/selftests/kvm/include/perf_test_util.h
@@ -39,6 +39,7 @@ struct perf_test_args {
/* Run vCPUs in L2 instead of L1, if the architecture supports it. */
bool nested;
+ bool random_access;
struct perf_test_vcpu_args vcpu_args[KVM_MAX_VCPUS];
};
@@ -53,6 +54,7 @@ void perf_test_destroy_vm(struct kvm_vm *vm);
void perf_test_set_write_percent(struct kvm_vm *vm, uint32_t write_percent);
void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed);
+void perf_test_set_random_access(struct kvm_vm *vm, bool random_access);
void perf_test_start_vcpu_threads(int vcpus, void (*vcpu_fn)(struct perf_test_vcpu_args *));
void perf_test_join_vcpu_threads(int vcpus);
diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c
index be6176faaf8e..c6123b75d5e3 100644
--- a/tools/testing/selftests/kvm/lib/perf_test_util.c
+++ b/tools/testing/selftests/kvm/lib/perf_test_util.c
@@ -53,6 +53,7 @@ void perf_test_guest_code(uint32_t vcpu_id)
struct perf_test_vcpu_args *vcpu_args = &pta->vcpu_args[vcpu_id];
uint64_t gva;
uint64_t pages;
+ uint64_t addr;
int i;
uint32_t rand = pta->random_seed + vcpu_id;
@@ -64,7 +65,14 @@ void perf_test_guest_code(uint32_t vcpu_id)
while (true) {
for (i = 0; i < pages; i++) {
- uint64_t addr = gva + (i * pta->guest_page_size);
+ rand = perf_test_random(rand);
+
+ if (pta->random_access)
+ addr = gva +
+ ((rand % pages) * pta->guest_page_size);
+ else
+ addr = gva + (i * pta->guest_page_size);
+
rand = perf_test_random(rand);
if (rand % 100 < pta->write_percent)
@@ -240,6 +248,12 @@ void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed)
sync_global_to_guest(vm, perf_test_args);
}
+void perf_test_set_random_access(struct kvm_vm *vm, bool random_access)
+{
+ perf_test_args.random_access = random_access;
+ sync_global_to_guest(vm, perf_test_args);
+}
+
uint64_t __weak perf_test_nested_pages(int nr_vcpus)
{
return 0;
--
2.37.2.789.g6183377224-goog
