Apply minor fix and documentation to ThreadPool

This commit is contained in:
Stephen Seo 2022-06-16 13:38:53 +09:00
parent 2745362e41
commit b4b0802e7c

View file

@ -36,8 +36,8 @@ using PointersT =
/*!
\brief Implementation of a Thread Pool.
Note that if SIZE is less than 2, then ThreadPool will not create threads
and run queued functions on the calling thread.
Note that MAXSIZE template parameter determines how many threads are created
each time that startThreads() (or easyStartAndWait()) is called.
*/
template <unsigned int MAXSIZE>
class ThreadPool {
@ -54,15 +54,26 @@ class ThreadPool {
/*!
\brief Queues a function to be called (doesn't start calling yet).
To run the queued functions, wakeThreads() must be called to wake the
To run the queued functions, startThreads() must be called to wake the
waiting threads which will start pulling functions from the queue to be
called.
Note that the easyStartAndWait() calls startThreads() and waits until
the threads have finished execution.
*/
void queueFn(std::function<void(void *)> &&fn, void *ud = nullptr) {
std::lock_guard<std::mutex> lock(queueMutex);
fnQueue.emplace(std::make_tuple(fn, ud));
}
/*!
\brief Creates MAXSIZE threads that will process queueFn() functions.
Note that if MAXSIZE < 2, then this function will synchronously execute
the queued functions and block until the functions have been executed.
Otherwise, this function may return before the queued functions have
been executed.
*/
Internal::PointersT startThreads() {
if (MAXSIZE >= 2) {
checkStacks();
@ -132,15 +143,14 @@ class ThreadPool {
},
threadStack, threadStackMutex, &fnQueue, &queueMutex,
aCounter);
// Wait until thread has pushed to threadStack before setting
// the handle to it
while (aCounter->load() != i + 1) {
std::this_thread::sleep_for(std::chrono::microseconds(15));
}
std::lock_guard<std::mutex> stackLock(*threadStackMutex);
std::get<0>(threadStack->at(i)).reset(newThread);
}
while (aCounter->load() != MAXSIZE) {
std::this_thread::sleep_for(std::chrono::microseconds(15));
}
return pointers;
} else {
sequentiallyRunTasks();
@ -157,10 +167,16 @@ class ThreadPool {
}
/*!
\brief Returns the ThreadCount that this class was created with.
\brief Returns the MAXSIZE count that this class was created with.
*/
constexpr unsigned int getMaxThreadCount() { return MAXSIZE; }
/*!
\brief Calls startThreads() and waits until all threads have finished.
Regardless of the value set to MAXSIZE, this function will block until
all previously queued functions have been executed.
*/
void easyStartAndWait() {
if (MAXSIZE >= 2) {
Internal::PointersT pointers = startThreads();
@ -194,6 +210,10 @@ class ThreadPool {
}
}
/*!
\brief Checks if any threads are currently running, returning true if
there are no threads running.
*/
bool isNotRunning() {
std::lock_guard<std::mutex> lock(dequesMutex);
auto tIter = threadStacks.begin();