@@ -26,7 +26,8 @@ FLATLIBS = lib/libcflat.a $(libgcc)
tests-common = $(TEST_DIR)/vmexit.flat $(TEST_DIR)/tsc.flat \
$(TEST_DIR)/smptest.flat $(TEST_DIR)/port80.flat \
$(TEST_DIR)/realmode.flat $(TEST_DIR)/msr.flat \
- $(TEST_DIR)/hypercall.flat $(TEST_DIR)/sieve.flat
+ $(TEST_DIR)/hypercall.flat $(TEST_DIR)/sieve.flat \
+ $(TEST_DIR)/kvmclock_test.flat
tests_and_config = $(TEST_DIR)/*.flat $(TEST_DIR)/unittests.cfg
@@ -70,6 +71,9 @@ $(TEST_DIR)/rmap_chain.flat: $(cstart.o) $(TEST_DIR)/rmap_chain.o \
$(TEST_DIR)/svm.flat: $(cstart.o) $(TEST_DIR)/vm.o
+$(TEST_DIR)/kvmclock_test.flat: $(cstart.o) $(TEST_DIR)/kvmclock.o \
+ $(TEST_DIR)/kvmclock_test.o
+
arch_clean:
$(RM) $(TEST_DIR)/*.o $(TEST_DIR)/*.flat \
$(TEST_DIR)/.*.d $(TEST_DIR)/lib/.*.d $(TEST_DIR)/lib/*.o
@@ -12,3 +12,4 @@ sieve: heavy memory access with no paging and with paging static and with paging
smptest: run smp_id() on every cpu and compares return value to number
tsc: write to tsc(0) and write to tsc(100000000000) and read it back
vmexit: long loops for each: cpuid, vmcall, mov_from_cr8, mov_to_cr8, inl_pmtimer, ipi, ipi+halt
+kvmclock_test: test of wallclock, monotonic cycle and performance of kvmclock
new file mode 100644
@@ -0,0 +1,166 @@
+#include "libcflat.h"
+#include "smp.h"
+#include "atomic.h"
+#include "processor.h"
+#include "kvmclock.h"
+
+#define DEFAULT_TEST_LOOPS 100000000L
+#define DEFAULT_THRESHOLD 5L
+
+struct test_info {
+ struct spinlock lock;
+ long loops; /* test loops */
+ u64 warps; /* warp count */
+ u64 stalls; /* stall count */
+ long long worst; /* worst warp */
+ volatile cycle_t last; /* last cycle seen by test */
+ atomic_t ncpus; /* number of cpu in the test*/
+ int check; /* check cycle ? */
+};
+
+struct test_info ti[4];
+
+static int wallclock_test(long sec, long threshold)
+{
+ long ksec, offset;
+ struct timespec ts;
+
+ printf("Wallclock test, threshold %ld\n", threshold);
+ kvm_get_wallclock(&ts);
+ ksec = ts.tv_sec;
+
+ offset = ksec - sec;
+ printf("Seconds get from host: %ld\n", sec);
+ printf("Seconds get from kvmclock: %ld\n", ksec);
+ printf("Offset: %ld\n", offset);
+
+ if (offset > threshold || offset < -threshold) {
+ printf("offset too large!\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+static void kvm_clock_test(void *data)
+{
+ struct test_info *hv_test_info = (struct test_info *)data;
+ long i, check = hv_test_info->check;
+
+ for (i = 0; i < hv_test_info->loops; i++){
+ cycle_t t0, t1;
+ long long delta;
+
+ if (check == 0) {
+ kvm_clock_read();
+ continue;
+ }
+
+ spin_lock(&hv_test_info->lock);
+ t1 = kvm_clock_read();
+ t0 = hv_test_info->last;
+ hv_test_info->last = kvm_clock_read();
+ spin_unlock(&hv_test_info->lock);
+
+ delta = t1 - t0;
+ if (delta < 0) {
+ spin_lock(&hv_test_info->lock);
+ ++hv_test_info->warps;
+ if (delta < hv_test_info->worst){
+ hv_test_info->worst = delta;
+ printf("Worst warp %lld %\n", hv_test_info->worst);
+ }
+ spin_unlock(&hv_test_info->lock);
+ }
+ if (delta == 0)
+ ++hv_test_info->stalls;
+
+ if (!((unsigned long)i & 31))
+ asm volatile("rep; nop");
+ }
+
+ atomic_dec(&hv_test_info->ncpus);
+}
+
+static int cycle_test(int ncpus, long loops, int check, struct test_info *ti)
+{
+ int i;
+ unsigned long long begin, end;
+
+ begin = rdtsc();
+
+ atomic_set(&ti->ncpus, ncpus);
+ ti->loops = loops;
+ ti->check = check;
+ for (i = ncpus - 1; i >= 0; i--)
+ on_cpu_async(i, kvm_clock_test, (void *)ti);
+
+ /* Wait for the end of other vcpu */
+ while(atomic_read(&ti->ncpus))
+ ;
+
+ end = rdtsc();
+
+ printf("Total vcpus: %d\n", ncpus);
+ printf("Test loops: %ld\n", ti->loops);
+ if (check == 1) {
+ printf("Total warps: %lld\n", ti->warps);
+ printf("Total stalls: %lld\n", ti->stalls);
+ printf("Worst warp: %lld\n", ti->worst);
+ } else
+ printf("TSC cycles: %lld\n", end - begin);
+
+ return ti->warps ? 1 : 0;
+}
+
+int main(int ac, char **av)
+{
+ int ncpus = cpu_count();
+ int nerr = 0, i;
+ long loops = DEFAULT_TEST_LOOPS;
+ long sec = 0;
+ long threshold = DEFAULT_THRESHOLD;
+
+ if (ac > 1)
+ loops = atol(av[1]);
+ if (ac > 2)
+ sec = atol(av[2]);
+ if (ac > 3)
+ threshold = atol(av[3]);
+
+ smp_init();
+
+ if (ncpus > MAX_CPU)
+ ncpus = MAX_CPU;
+ for (i = 0; i < ncpus; ++i)
+ on_cpu(i, kvm_clock_init, (void *)0);
+
+ if (ac > 2)
+ nerr += wallclock_test(sec, threshold);
+
+ printf("Check the stability of raw cycle ...\n");
+ pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT
+ | PVCLOCK_RAW_CYCLE_BIT);
+ if (cycle_test(ncpus, loops, 1, &ti[0]))
+ printf("Raw cycle is not stable\n");
+ else
+ printf("Raw cycle is stable\n");
+
+ pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT);
+ printf("Monotonic cycle test:\n");
+ nerr += cycle_test(ncpus, loops, 1, &ti[1]);
+
+ printf("Measure the performance of raw cycle ...\n");
+ pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT
+ | PVCLOCK_RAW_CYCLE_BIT);
+ cycle_test(ncpus, loops, 0, &ti[2]);
+
+ printf("Measure the performance of adjusted cycle ...\n");
+ pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT);
+ cycle_test(ncpus, loops, 0, &ti[3]);
+
+ for (i = 0; i < ncpus; ++i)
+ on_cpu(i, kvm_clock_clear, (void *)0);
+
+ return nerr > 0 ? 1 : 0;
+}
@@ -63,3 +63,8 @@ extra_params = -enable-nesting -cpu qemu64,+svm
file = svm.flat
smp = 2
extra_params = -cpu qemu64,-svm
+
+[kvmclock_test]
+file = kvmclock_test.flat
+smp = 2
+extra_params = --append "10000000 `date +%s`"