tvl-depot/third_party/abseil_cpp/absl/base/internal/sysinfo_test.cc
Vincent Ambo fc8dc48020 Add 'third_party/abseil_cpp/' from commit '768eb2ca2857342673fcd462792ce04b8bac3fa3'
git-subtree-dir: third_party/abseil_cpp
git-subtree-mainline: ffb2ae54be
git-subtree-split: 768eb2ca28
2020-05-20 02:32:24 +01:00

100 lines
3 KiB
C++

// Copyright 2017 The Abseil Authors.
//
// 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
//
// https://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 "absl/base/internal/sysinfo.h"
#ifndef _WIN32
#include <sys/types.h>
#include <unistd.h>
#endif
#include <thread> // NOLINT(build/c++11)
#include <unordered_set>
#include <vector>
#include "gtest/gtest.h"
#include "absl/synchronization/barrier.h"
#include "absl/synchronization/mutex.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
namespace {
TEST(SysinfoTest, NumCPUs) {
EXPECT_NE(NumCPUs(), 0)
<< "NumCPUs() should not have the default value of 0";
}
TEST(SysinfoTest, NominalCPUFrequency) {
#if !(defined(__aarch64__) && defined(__linux__)) && !defined(__EMSCRIPTEN__)
EXPECT_GE(NominalCPUFrequency(), 1000.0)
<< "NominalCPUFrequency() did not return a reasonable value";
#else
// Aarch64 cannot read the CPU frequency from sysfs, so we get back 1.0.
// Emscripten does not have a sysfs to read from at all.
EXPECT_EQ(NominalCPUFrequency(), 1.0)
<< "CPU frequency detection was fixed! Please update unittest.";
#endif
}
TEST(SysinfoTest, GetTID) {
EXPECT_EQ(GetTID(), GetTID()); // Basic compile and equality test.
#ifdef __native_client__
// Native Client has a race condition bug that leads to memory
// exaustion when repeatedly creating and joining threads.
// https://bugs.chromium.org/p/nativeclient/issues/detail?id=1027
return;
#endif
// Test that TIDs are unique to each thread.
// Uses a few loops to exercise implementations that reallocate IDs.
for (int i = 0; i < 10; ++i) {
constexpr int kNumThreads = 10;
Barrier all_threads_done(kNumThreads);
std::vector<std::thread> threads;
Mutex mutex;
std::unordered_set<pid_t> tids;
for (int j = 0; j < kNumThreads; ++j) {
threads.push_back(std::thread([&]() {
pid_t id = GetTID();
{
MutexLock lock(&mutex);
ASSERT_TRUE(tids.find(id) == tids.end());
tids.insert(id);
}
// We can't simply join the threads here. The threads need to
// be alive otherwise the TID might have been reallocated to
// another live thread.
all_threads_done.Block();
}));
}
for (auto& thread : threads) {
thread.join();
}
}
}
#ifdef __linux__
TEST(SysinfoTest, LinuxGetTID) {
// On Linux, for the main thread, GetTID()==getpid() is guaranteed by the API.
EXPECT_EQ(GetTID(), getpid());
}
#endif
} // namespace
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl