cmWorkerPool: Set worker thread count separately to Process()
Don't pass the desired worker thread count to the `cmWorkerPool::Process()`
method but set it separately with the new `cmWorkerPool::SetThreadCount`
method. This allows calling `cmWorkerPool::Process()` repeatedly without
having to pass the thread count every time.
diff --git a/Source/cmQtAutoMocUic.cxx b/Source/cmQtAutoMocUic.cxx
index 75c5d8a..005c27d 100644
--- a/Source/cmQtAutoMocUic.cxx
+++ b/Source/cmQtAutoMocUic.cxx
@@ -1186,6 +1186,7 @@
num = std::min<unsigned long>(num, ParallelMax);
Base_.NumThreads = static_cast<unsigned int>(num);
}
+ WorkerPool_.SetThreadCount(Base_.NumThreads);
}
// - Files and directories
@@ -1482,15 +1483,12 @@
if (!CreateDirectories()) {
return false;
}
-
- if (!WorkerPool_.Process(Base().NumThreads, this)) {
+ if (!WorkerPool_.Process(this)) {
return false;
}
-
if (JobError_) {
return false;
}
-
return SettingsFileWrite();
}
diff --git a/Source/cmWorkerPool.cxx b/Source/cmWorkerPool.cxx
index 464182c..75ca47a 100644
--- a/Source/cmWorkerPool.cxx
+++ b/Source/cmWorkerPool.cxx
@@ -468,6 +468,7 @@
// -- Thread pool and job queue
std::mutex Mutex;
+ bool Processing = false;
bool Aborting = false;
bool FenceProcessing = false;
unsigned int WorkersRunning = 0;
@@ -591,7 +592,8 @@
bool cmWorkerPoolInternal::Process()
{
- // Reset state
+ // Reset state flags
+ Processing = true;
Aborting = false;
// Initialize libuv asynchronous request
UVRequestBegin.init(*UVLoop, &cmWorkerPoolInternal::UVSlotBegin, this);
@@ -599,23 +601,27 @@
// Send begin request
UVRequestBegin.send();
// Run libuv loop
- return (uv_run(UVLoop.get(), UV_RUN_DEFAULT) == 0);
+ bool success = (uv_run(UVLoop.get(), UV_RUN_DEFAULT) == 0);
+ // Update state flags
+ Processing = false;
+ Aborting = false;
+ return success;
}
void cmWorkerPoolInternal::Abort()
{
- bool firstCall = false;
+ bool notifyThreads = false;
// Clear all jobs and set abort flag
{
std::lock_guard<std::mutex> guard(Mutex);
- if (!Aborting) {
+ if (Processing && !Aborting) {
// Register abort and clear queue
Aborting = true;
Queue.clear();
- firstCall = true;
+ notifyThreads = true;
}
}
- if (firstCall) {
+ if (notifyThreads) {
// Wake threads
Condition.notify_all();
}
@@ -627,15 +633,13 @@
if (Aborting) {
return false;
}
-
// Append the job to the queue
Queue.emplace_back(std::move(jobHandle));
-
// Notify an idle worker if there's one
if (WorkersIdle != 0) {
Condition.notify_one();
}
-
+ // Return success
return true;
}
@@ -743,19 +747,22 @@
cmWorkerPool::~cmWorkerPool() = default;
-bool cmWorkerPool::Process(unsigned int threadCount, void* userData)
+void cmWorkerPool::SetThreadCount(unsigned int threadCount)
+{
+ if (!Int_->Processing) {
+ ThreadCount_ = (threadCount > 0) ? threadCount : 1u;
+ }
+}
+
+bool cmWorkerPool::Process(void* userData)
{
// Setup user data
UserData_ = userData;
- ThreadCount_ = (threadCount > 0) ? threadCount : 1u;
-
// Run libuv loop
bool success = Int_->Process();
-
// Clear user data
UserData_ = nullptr;
- ThreadCount_ = 0;
-
+ // Return
return success;
}
diff --git a/Source/cmWorkerPool.h b/Source/cmWorkerPool.h
index 71c7d84..f08bb4f 100644
--- a/Source/cmWorkerPool.h
+++ b/Source/cmWorkerPool.h
@@ -50,12 +50,12 @@
JobT& operator=(JobT const&) = delete;
/**
- * @brief Virtual destructor.
+ * Virtual destructor.
*/
virtual ~JobT();
/**
- * @brief Fence job flag
+ * Fence job flag
*
* Fence jobs require that:
* - all jobs before in the queue have been processed
@@ -66,7 +66,7 @@
protected:
/**
- * @brief Protected default constructor
+ * Protected default constructor
*/
JobT(bool fence = false)
: Fence_(fence)
@@ -125,12 +125,12 @@
};
/**
- * @brief Job handle type
+ * Job handle type
*/
typedef std::unique_ptr<JobT> JobHandleT;
/**
- * @brief Fence job base class
+ * Fence job base class
*/
class JobFenceT : public JobT
{
@@ -144,8 +144,9 @@
};
/**
- * @brief Fence job that aborts the worker pool.
- * This class is useful as the last job in the job queue.
+ * Fence job that aborts the worker pool.
+ *
+ * Useful as the last job in the job queue.
*/
class JobEndT : JobFenceT
{
@@ -160,23 +161,29 @@
~cmWorkerPool();
/**
- * @brief Blocking function that starts threads to process all Jobs in
- * the queue.
+ * Number of worker threads.
+ */
+ unsigned int ThreadCount() const { return ThreadCount_; }
+
+ /**
+ * Set the number of worker threads.
+ *
+ * Calling this method during Process() has no effect.
+ */
+ void SetThreadCount(unsigned int threadCount);
+
+ /**
+ * Blocking function that starts threads to process all Jobs in the queue.
*
* This method blocks until a job calls the Abort() method.
* @arg threadCount Number of threads to process jobs.
* @arg userData Common user data pointer available in all Jobs.
*/
- bool Process(unsigned int threadCount, void* userData = nullptr);
-
- /**
- * Number of worker threads passed to Process().
- * Only valid during Process().
- */
- unsigned int ThreadCount() const { return ThreadCount_; }
+ bool Process(void* userData = nullptr);
/**
* User data reference passed to Process().
+ *
* Only valid during Process().
*/
void* UserData() const { return UserData_; }
@@ -184,14 +191,14 @@
// -- Job processing interface
/**
- * @brief Clears the job queue and aborts all worker threads.
+ * Clears the job queue and aborts all worker threads.
*
* This method is thread safe and can be called from inside a job.
*/
void Abort();
/**
- * @brief Push job to the queue.
+ * Push job to the queue.
*
* This method is thread safe and can be called from inside a job or before
* Process().
@@ -199,7 +206,7 @@
bool PushJob(JobHandleT&& jobHandle);
/**
- * @brief Push job to the queue
+ * Push job to the queue
*
* This method is thread safe and can be called from inside a job or before
* Process().
@@ -212,7 +219,7 @@
private:
void* UserData_ = nullptr;
- unsigned int ThreadCount_ = 0;
+ unsigned int ThreadCount_ = 1;
std::unique_ptr<cmWorkerPoolInternal> Int_;
};
