105 lines
3.1 KiB
C++
105 lines
3.1 KiB
C++
// Copyright 2018 Google LLC
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#include <stdint.h>
|
|
#include <sys/time.h>
|
|
#include <syscall.h>
|
|
#include <time.h>
|
|
#include <unistd.h>
|
|
#include <map>
|
|
#include <string>
|
|
#include <utility>
|
|
|
|
#include "gmock/gmock.h"
|
|
#include "gtest/gtest.h"
|
|
#include "absl/strings/numbers.h"
|
|
#include "absl/time/clock.h"
|
|
#include "absl/time/time.h"
|
|
#include "test/util/test_util.h"
|
|
|
|
namespace gvisor {
|
|
namespace testing {
|
|
|
|
namespace {
|
|
|
|
std::string PrintClockId(::testing::TestParamInfo<clockid_t> info) {
|
|
switch (info.param) {
|
|
case CLOCK_MONOTONIC:
|
|
return "CLOCK_MONOTONIC";
|
|
case CLOCK_REALTIME:
|
|
return "CLOCK_REALTIME";
|
|
default:
|
|
return absl::StrCat(info.param);
|
|
}
|
|
}
|
|
|
|
class CorrectVDSOClockTest : public ::testing::TestWithParam<clockid_t> {};
|
|
|
|
TEST_P(CorrectVDSOClockTest, IsCorrect) {
|
|
struct timespec tvdso, tsys;
|
|
absl::Time vdso_time, sys_time;
|
|
uint64_t total_calls = 0;
|
|
|
|
// It is expected that 82.5% of clock_gettime calls will be less than 100us
|
|
// skewed from the system time.
|
|
// Unfortunately this is not only influenced by the VDSO clock skew, but also
|
|
// by arbitrary scheduling delays and the like. The test is therefore
|
|
// regularly disabled.
|
|
std::map<absl::Duration, std::tuple<double, uint64_t, uint64_t>> confidence =
|
|
{
|
|
{absl::Microseconds(100), std::make_tuple(0.825, 0, 0)},
|
|
{absl::Microseconds(250), std::make_tuple(0.94, 0, 0)},
|
|
{absl::Milliseconds(1), std::make_tuple(0.999, 0, 0)},
|
|
};
|
|
|
|
absl::Time start = absl::Now();
|
|
while (absl::Now() < start + absl::Seconds(30)) {
|
|
EXPECT_THAT(clock_gettime(GetParam(), &tvdso), SyscallSucceeds());
|
|
EXPECT_THAT(syscall(__NR_clock_gettime, GetParam(), &tsys),
|
|
SyscallSucceeds());
|
|
|
|
vdso_time = absl::TimeFromTimespec(tvdso);
|
|
|
|
for (auto const& conf : confidence) {
|
|
std::get<1>(confidence[conf.first]) +=
|
|
(sys_time - vdso_time) < conf.first;
|
|
}
|
|
|
|
sys_time = absl::TimeFromTimespec(tsys);
|
|
|
|
for (auto const& conf : confidence) {
|
|
std::get<2>(confidence[conf.first]) +=
|
|
(vdso_time - sys_time) < conf.first;
|
|
}
|
|
|
|
++total_calls;
|
|
}
|
|
|
|
for (auto const& conf : confidence) {
|
|
EXPECT_GE(std::get<1>(conf.second) / static_cast<double>(total_calls),
|
|
std::get<0>(conf.second));
|
|
EXPECT_GE(std::get<2>(conf.second) / static_cast<double>(total_calls),
|
|
std::get<0>(conf.second));
|
|
}
|
|
}
|
|
|
|
INSTANTIATE_TEST_CASE_P(ClockGettime, CorrectVDSOClockTest,
|
|
::testing::Values(CLOCK_MONOTONIC, CLOCK_REALTIME),
|
|
PrintClockId);
|
|
|
|
} // namespace
|
|
|
|
} // namespace testing
|
|
} // namespace gvisor
|