SERVER-40111 Switch ThreadPool classes from try-catch to noexcept

5 files changed, 24 insertions, 43 deletions

diff --git a/src/mongo/executor/network_interface_thread_pool.cpp b/src/mongo/executor/network_interface_thread_pool.cpp
index 4620d9bc19f..0fa5ed7632e 100644
--- a/src/mongo/executor/network_interface_thread_pool.cpp
+++ b/src/mongo/executor/network_interface_thread_pool.cpp
@@ -148,7 +148,7 @@ void NetworkInterfaceThreadPool::_consumeTasks(stdx::unique_lock<stdx::mutex> lk
     invariant(ret.isOK() || ErrorCodes::isShutdownError(ret.code()));
 }
 
-void NetworkInterfaceThreadPool::_consumeTasksInline(stdx::unique_lock<stdx::mutex> lk) {
+void NetworkInterfaceThreadPool::_consumeTasksInline(stdx::unique_lock<stdx::mutex> lk) noexcept {
     _consumeState = ConsumeState::kConsuming;
     const auto consumingTasksGuard = makeGuard([&] { _consumeState = ConsumeState::kNeutral; });
 
@@ -162,12 +162,7 @@ void NetworkInterfaceThreadPool::_consumeTasksInline(stdx::unique_lock<stdx::mut
         const auto lkGuard = makeGuard([&] { lk.lock(); });
 
         for (auto&& task : tasks) {
-            try {
-                task();
-            } catch (...) {
-                severe() << "Exception escaped task in network interface thread pool";
-                std::terminate();
-            }
+            task();
         }
 
         tasks.clear();
diff --git a/src/mongo/executor/network_interface_thread_pool.h b/src/mongo/executor/network_interface_thread_pool.h
index da9146f6fe6..712ad2d6df7 100644
--- a/src/mongo/executor/network_interface_thread_pool.h
+++ b/src/mongo/executor/network_interface_thread_pool.h
@@ -61,7 +61,7 @@ public:
 
 private:
     void _consumeTasks(stdx::unique_lock<stdx::mutex> lk);
-    void _consumeTasksInline(stdx::unique_lock<stdx::mutex> lk);
+    void _consumeTasksInline(stdx::unique_lock<stdx::mutex> lk) noexcept;
     void _dtorImpl();
 
     NetworkInterface* const _net;
diff --git a/src/mongo/util/concurrency/thread_pool.cpp b/src/mongo/util/concurrency/thread_pool.cpp
index 755ad56bffd..81f1e3c2285 100644
--- a/src/mongo/util/concurrency/thread_pool.cpp
+++ b/src/mongo/util/concurrency/thread_pool.cpp
@@ -130,14 +130,8 @@ void ThreadPool::_shutdown_inlock() {
 }
 
 void ThreadPool::join() {
-    try {
-        stdx::unique_lock<stdx::mutex> lk(_mutex);
-        _join_inlock(&lk);
-    } catch (...) {
-        severe() << "Exception escaped join in thread pool " << _options.poolName << ": "
-                 << exceptionToStatus();
-        std::terminate();
-    }
+    stdx::unique_lock<stdx::mutex> lk(_mutex);
+    _join_inlock(&lk);
 }
 
 void ThreadPool::_join_inlock(stdx::unique_lock<stdx::mutex>* lk) {
@@ -244,13 +238,7 @@ void ThreadPool::_workerThreadBody(ThreadPool* pool, const std::string& threadNa
     pool->_options.onCreateThread(threadName);
     const auto poolName = pool->_options.poolName;
     LOG(1) << "starting thread in pool " << poolName;
-    try {
-        pool->_consumeTasks();
-    } catch (...) {
-        severe() << "Exception reached top of stack in thread pool " << poolName << ": "
-                 << exceptionToStatus();
-        std::terminate();
-    }
+    pool->_consumeTasks();
 
     // At this point, another thread may have destroyed "pool", if this thread chose to detach
     // itself and remove itself from pool->_threads before releasing pool->_mutex.  Do not access
@@ -337,24 +325,18 @@ void ThreadPool::_consumeTasks() {
     fassertFailedNoTrace(28703);
 }
 
-void ThreadPool::_doOneTask(stdx::unique_lock<stdx::mutex>* lk) {
+void ThreadPool::_doOneTask(stdx::unique_lock<stdx::mutex>* lk) noexcept {
     invariant(!_pendingTasks.empty());
-    try {
-        LOG(3) << "Executing a task on behalf of pool " << _options.poolName;
-        Task task = std::move(_pendingTasks.front());
-        _pendingTasks.pop_front();
-        --_numIdleThreads;
-        lk->unlock();
-        task();
-        lk->lock();
-        ++_numIdleThreads;
-        if (_pendingTasks.empty() && _threads.size() == _numIdleThreads) {
-            _poolIsIdle.notify_all();
-        }
-    } catch (...) {
-        severe() << "Exception escaped task in thread pool " << _options.poolName << ": "
-                 << exceptionToStatus();
-        std::terminate();
+    LOG(3) << "Executing a task on behalf of pool " << _options.poolName;
+    Task task = std::move(_pendingTasks.front());
+    _pendingTasks.pop_front();
+    --_numIdleThreads;
+    lk->unlock();
+    task();
+    lk->lock();
+    ++_numIdleThreads;
+    if (_pendingTasks.empty() && _threads.size() == _numIdleThreads) {
+        _poolIsIdle.notify_all();
     }
 }
 
diff --git a/src/mongo/util/concurrency/thread_pool.h b/src/mongo/util/concurrency/thread_pool.h
index 16e9ada80bd..b95956c4832 100644
--- a/src/mongo/util/concurrency/thread_pool.h
+++ b/src/mongo/util/concurrency/thread_pool.h
@@ -201,7 +201,7 @@ private:
      * Executes one task from _pendingTasks. "lk" must own _mutex, and _pendingTasks must have at
      * least one entry.
      */
-    void _doOneTask(stdx::unique_lock<stdx::mutex>* lk);
+    void _doOneTask(stdx::unique_lock<stdx::mutex>* lk) noexcept;
 
     /**
      * Changes the lifecycle state (_state) of the pool and wakes up any threads waiting for a state
diff --git a/src/mongo/util/concurrency/thread_pool_test_common.cpp b/src/mongo/util/concurrency/thread_pool_test_common.cpp
index 70a0c41ef19..5df135ac19c 100644
--- a/src/mongo/util/concurrency/thread_pool_test_common.cpp
+++ b/src/mongo/util/concurrency/thread_pool_test_common.cpp
@@ -151,11 +151,15 @@ COMMON_THREAD_POOL_DEATH_TEST(DieOnDoubleStartUp, "it has already started") {
     pool.startup();
 }
 
-COMMON_THREAD_POOL_DEATH_TEST(DieWhenExceptionBubblesUp, "Exception escaped task in") {
+namespace {
+constexpr auto kExceptionMessage = "No good very bad exception";
+}
+
+COMMON_THREAD_POOL_DEATH_TEST(DieWhenExceptionBubblesUp, kExceptionMessage) {
     auto& pool = getThreadPool();
     pool.startup();
     ASSERT_OK(pool.schedule([] {
-        uassertStatusOK(Status({ErrorCodes::BadValue, "No good very bad exception"}));
+        uassertStatusOK(Status({ErrorCodes::BadValue, kExceptionMessage}));
     }));
     pool.shutdown();
     pool.join();