Merge changes from The Witness.

src/nvthread/Event.cpp

@@ -34,25 +34,33 @@ void Event::wait() {
 
 #elif NV_OS_UNIX
 
-// @@ TODO
 #pragma NV_MESSAGE("Implement event using pthreads!")
 
 struct Event::Private {
+    pthread_cond_t pt_cond;
+    pthread_mutex_t pt_mutex;
 };
 
 Event::Event() : m(new Private) {
+    // pthread equivalent of auto-reset event
+    pthread_cond_init(&m->pt_cond, NULL);
+    pthread_mutex_init(&m->pt_mutex, NULL);
 }
 
 Event::~Event() {
+    pthread_cond_destroy(&m->pt_cond);
+    pthread_mutex_destroy(&m->pt_mutex);
 }
 
 void Event::post() {
+    pthread_cond_signal(&m->pt_cond);
 }
 
 void Event::wait() {
+    pthread_cond_wait(&m->pt_cond, &m->pt_mutex);
 }
 
-#endif	
+#endif // NV_OS_UNIX
 
 
 /*static*/ void Event::post(Event * events, uint count) {

src/nvthread/Thread.cpp

@@ -27,7 +27,7 @@ struct Thread::Private
 #if NV_OS_WIN32
 
 unsigned long __stdcall threadFunc(void * arg) {
-    Thread * thread = (Thread *)arg;
+    Thread::Private * thread = (Thread::Private *)arg;
     thread->func(thread->arg);
     return 0;
 }
@@ -35,7 +35,7 @@ unsigned long __stdcall threadFunc(void * arg) {
 #elif NV_OS_UNIX
 
 extern "C" void * threadFunc(void * arg) {
-    Thread * thread = (Thread *)arg;
+    Thread::Private * thread = (Thread::Private *)arg;
     thread->func(thread->arg);
     pthread_exit(0);
 }
@@ -55,15 +55,15 @@ Thread::~Thread()
 
 void Thread::start(ThreadFunc * func, void * arg)
 {
-    this->func = func;
-    this->arg = arg;
+    p->func = func;
+    p->arg = arg;
 
 #if NV_OS_WIN32
-    p->thread = CreateThread(NULL, 0, threadFunc, this, 0, NULL);
-    //p->thread = (HANDLE)_beginthreadex (0, 0, threadFunc, this, 0, NULL);     // @@ So that we can call CRT functions...
+    p->thread = CreateThread(NULL, 0, threadFunc, p.ptr(), 0, NULL);
+    //p->thread = (HANDLE)_beginthreadex (0, 0, threadFunc, p.ptr(), 0, NULL);     // @@ So that we can call CRT functions...
     nvDebugCheck(p->thread != NULL);
 #elif NV_OS_UNIX
-    int result = pthread_create(&p->thread, NULL, threadFunc, this);
+    int result = pthread_create(&p->thread, NULL, threadFunc, p.ptr());
     nvDebugCheck(result == 0);
 #endif
 }

src/nvthread/Thread.h

@@ -6,7 +6,7 @@
 
 #include "nvthread.h"
 
-#include "nvcore/Ptr.h"
+#include "nvcore/Ptr.h" // AutoPtr
 
 namespace nv
 {
@@ -30,15 +30,8 @@ namespace nv
 
         static void wait(Thread * threads, uint count);
 
-    private:
-
         struct Private;
         AutoPtr<Private> p;
-
-    public: // @@ Why public? Also in private?!
-        ThreadFunc * func;
-        void * arg;
-
     };
 
 } // nv namespace

src/nvthread/ThreadPool.cpp

@@ -79,6 +79,8 @@ ThreadPool::ThreadPool()
     startEvents = new Event[workerCount];
     finishEvents = new Event[workerCount];
 
+    nvCompilerWriteBarrier(); // @@ Use a memory fence?
+
     for (uint i = 0; i < workerCount; i++) {
         workers[i].start(workerFunc, (void *)i);
     }
@@ -110,8 +112,6 @@ void ThreadPool::start(ThreadFunc * func, void * arg)
 
     allIdle = false;
 
-    nvCompilerWriteBarrier();
-
     // Resume threads.
     Event::post(startEvents, workerCount);
 }

src/nvthread/ThreadPool.h

@@ -9,6 +9,12 @@
 #include "Event.h"
 #include "Thread.h"
 
+// The thread pool creates one worker thread for each physical core. 
+// The threads are idle waiting for their start events so that they do not consume any resources while inactive. 
+// The thread pool runs the same function in all worker threads, the idea is to use this as the foundation of a custom task scheduler.
+// When the thread pool starts, the main thread continues running, but the common use case is to inmmediately wait of the termination events of the worker threads.
+// @@ The start and wait methods could probably be merged.
+
 namespace nv {
 
     class Thread;

src/nvthread/nvthread.cpp

@@ -9,14 +9,13 @@
 #elif NV_OS_UNIX
 #include <sys/types.h>
 #include <sys/sysctl.h>
-#include <unistd.h>
 #elif NV_OS_DARWIN
 #import <stdio.h>
 #import <string.h>
 #import <mach/mach_host.h>
 #import <sys/sysctl.h>
 
-#include <CoreFoundation/CoreFoundation.h>
+//#include <CoreFoundation/CoreFoundation.h>
 
 #include <assert.h>
 #include <errno.h>