llvm-project/clang-tools-extra/unittests/clangd/ThreadingTests.cpp

66 lines
1.9 KiB
C++

//===-- ThreadingTests.cpp --------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Threading.h"
#include "gtest/gtest.h"
#include <mutex>
namespace clang {
namespace clangd {
class ThreadingTest : public ::testing::Test {};
TEST_F(ThreadingTest, TaskRunner) {
const int TasksCnt = 100;
// This should be const, but MSVC does not allow to use const vars in lambdas
// without capture. On the other hand, clang gives a warning that capture of
// const var is not required.
// Making it non-const makes both compilers happy.
int IncrementsPerTask = 1000;
std::mutex Mutex;
int Counter(0); /* GUARDED_BY(Mutex) */
{
AsyncTaskRunner Tasks;
auto scheduleIncrements = [&]() {
for (int TaskI = 0; TaskI < TasksCnt; ++TaskI) {
Tasks.runAsync("task", [&Counter, &Mutex, IncrementsPerTask]() {
for (int Increment = 0; Increment < IncrementsPerTask; ++Increment) {
std::lock_guard<std::mutex> Lock(Mutex);
++Counter;
}
});
}
};
{
// Make sure runAsync is not running tasks synchronously on the same
// thread by locking the Mutex used for increments.
std::lock_guard<std::mutex> Lock(Mutex);
scheduleIncrements();
}
Tasks.wait();
{
std::lock_guard<std::mutex> Lock(Mutex);
ASSERT_EQ(Counter, TasksCnt * IncrementsPerTask);
}
{
std::lock_guard<std::mutex> Lock(Mutex);
Counter = 0;
scheduleIncrements();
}
}
// Check that destructor has waited for tasks to finish.
std::lock_guard<std::mutex> Lock(Mutex);
ASSERT_EQ(Counter, TasksCnt * IncrementsPerTask);
}
} // namespace clangd
} // namespace clang