1 // Copyright 2017 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "absl/base/internal/sysinfo.h"
16
17 #ifndef _WIN32
18 #include <sys/types.h>
19 #include <unistd.h>
20 #endif
21
22 #include <thread> // NOLINT(build/c++11)
23 #include <unordered_set>
24 #include <vector>
25
26 #include "gtest/gtest.h"
27 #include "absl/synchronization/barrier.h"
28 #include "absl/synchronization/mutex.h"
29
30 namespace absl {
31 ABSL_NAMESPACE_BEGIN
32 namespace base_internal {
33 namespace {
34
TEST(SysinfoTest,NumCPUs)35 TEST(SysinfoTest, NumCPUs) {
36 EXPECT_NE(NumCPUs(), 0)
37 << "NumCPUs() should not have the default value of 0";
38 }
39
TEST(SysinfoTest,NominalCPUFrequency)40 TEST(SysinfoTest, NominalCPUFrequency) {
41 #if !(defined(__aarch64__) && defined(__linux__)) && !defined(__EMSCRIPTEN__)
42 EXPECT_GE(NominalCPUFrequency(), 1000.0)
43 << "NominalCPUFrequency() did not return a reasonable value";
44 #else
45 // Aarch64 cannot read the CPU frequency from sysfs, so we get back 1.0.
46 // Emscripten does not have a sysfs to read from at all.
47 EXPECT_EQ(NominalCPUFrequency(), 1.0)
48 << "CPU frequency detection was fixed! Please update unittest.";
49 #endif
50 }
51
TEST(SysinfoTest,GetTID)52 TEST(SysinfoTest, GetTID) {
53 EXPECT_EQ(GetTID(), GetTID()); // Basic compile and equality test.
54 #ifdef __native_client__
55 // Native Client has a race condition bug that leads to memory
56 // exaustion when repeatedly creating and joining threads.
57 // https://bugs.chromium.org/p/nativeclient/issues/detail?id=1027
58 return;
59 #endif
60 // Test that TIDs are unique to each thread.
61 // Uses a few loops to exercise implementations that reallocate IDs.
62 for (int i = 0; i < 10; ++i) {
63 constexpr int kNumThreads = 10;
64 Barrier all_threads_done(kNumThreads);
65 std::vector<std::thread> threads;
66
67 Mutex mutex;
68 std::unordered_set<pid_t> tids;
69
70 for (int j = 0; j < kNumThreads; ++j) {
71 threads.push_back(std::thread([&]() {
72 pid_t id = GetTID();
73 {
74 MutexLock lock(&mutex);
75 ASSERT_TRUE(tids.find(id) == tids.end());
76 tids.insert(id);
77 }
78 // We can't simply join the threads here. The threads need to
79 // be alive otherwise the TID might have been reallocated to
80 // another live thread.
81 all_threads_done.Block();
82 }));
83 }
84 for (auto& thread : threads) {
85 thread.join();
86 }
87 }
88 }
89
90 #ifdef __linux__
TEST(SysinfoTest,LinuxGetTID)91 TEST(SysinfoTest, LinuxGetTID) {
92 // On Linux, for the main thread, GetTID()==getpid() is guaranteed by the API.
93 EXPECT_EQ(GetTID(), getpid());
94 }
95 #endif
96
97 } // namespace
98 } // namespace base_internal
99 ABSL_NAMESPACE_END
100 } // namespace absl
101