X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=Robust%2Fsrc%2FRuntime%2Fworkschedule.c;h=5b24b68d1769d46b4526ff948aacc88604a8c107;hb=296a232a015befc68bef08897bd7d3e45f1aca4f;hp=659280717815a458c1c7a80e7fc9aa626fd720be;hpb=edae4bedef87b02fa16acc12b68fc4727d90a6a4;p=IRC.git

diff --git a/Robust/src/Runtime/workschedule.c b/Robust/src/Runtime/workschedule.c
index 65928071..5b24b68d 100644
--- a/Robust/src/Runtime/workschedule.c
+++ b/Robust/src/Runtime/workschedule.c
@@ -28,8 +28,12 @@ typedef struct workerData_t {
   int             nextWorkerToLoad;
 } workerData;
 */
+
+
+static pthread_mutex_t systemLock;
+
 // just one queue for everyone
-static pthread_mutex_t dequeLock;
+//static pthread_mutex_t dequeLock;
 static deq*            dequeWorkUnits;
 
 
@@ -38,12 +42,18 @@ static deq*            dequeWorkUnits;
 static int             numWorkers;
 //static workerData*     workerDataArray;
 static pthread_t*      workerArray;
-static pthread_mutex_t systemBeginLock  = PTHREAD_MUTEX_INITIALIZER;
+
+static int systemStarted = 0;
+
+//static pthread_mutex_t systemBeginLock  = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t  systemBeginCond  = PTHREAD_COND_INITIALIZER;
-static pthread_mutex_t systemReturnLock = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t  systemReturnCond = PTHREAD_COND_INITIALIZER;
+//static pthread_mutex_t systemReturnLock = PTHREAD_MUTEX_INITIALIZER;
+//static pthread_cond_t  systemReturnCond = PTHREAD_COND_INITIALIZER;
 static void(*workFunc)(void*);
 
+static pthread_cond_t  workAvailCond  = PTHREAD_COND_INITIALIZER;
+
+
 
 /*
 // helper func
@@ -144,35 +154,29 @@ void* workerMain( void* arg ) {
   
   void* workUnit;
 
-  int tries = 3;
-
   // all workers wait until system is ready
-  pthread_mutex_lock  ( &systemBeginLock );
-  pthread_cond_wait   ( &systemBeginCond, &systemBeginLock );
-  pthread_mutex_unlock( &systemBeginLock );
-
-  while( tries > 0 ) {
-
-    pthread_mutex_lock( &dequeLock );
+  pthread_mutex_lock  ( &systemLock );
+  while( !systemStarted ) {
+    pthread_cond_wait( &systemBeginCond, &systemLock );
+  }
+  pthread_mutex_unlock( &systemLock );
 
-    // look in the queue for work
-    if( !isEmpty( dequeWorkUnits ) ) {
-      workUnit = getItem( dequeWorkUnits );
-    } else {
-      workUnit = NULL;
-    }
+  while( 1 ) {
 
-    pthread_mutex_unlock( &dequeLock );
+    pthread_mutex_lock( &systemLock );
+    // wait for work
+    while( isEmpty( dequeWorkUnits ) ) {
+      pthread_cond_wait( &workAvailCond, &systemLock );
+    }     
+    workUnit = getItem( dequeWorkUnits );
+    pthread_mutex_unlock( &systemLock );
 
-    // yield processor before moving on
+    // yield processor before moving on, just to exercise
+    // system's out-of-order correctness
     if( sched_yield() == -1 ) { printf( "Error thread trying to yield.\n" ); exit( -1 ); }
-
-    if( workUnit != NULL ) {   
-      workFunc( workUnit );
-      tries = 3;
-    } else {
-      --tries;
-    }
+    if( sched_yield() == -1 ) { printf( "Error thread trying to yield.\n" ); exit( -1 ); }
+    
+    workFunc( workUnit );
   }
 
   return NULL;
@@ -236,7 +240,7 @@ void workScheduleInit( int numProcessors,
 
   dequeWorkUnits = createQueue();
 
-  status = pthread_mutex_init( &dequeLock, NULL );
+  status = pthread_mutex_init( &systemLock, NULL );
   if( status != 0 ) { printf( "Error\n" ); exit( -1 ); }
 
   workerArray = RUNMALLOC( sizeof( pthread_t ) * numWorkers );
@@ -275,9 +279,10 @@ void workScheduleSubmit( void* workUnit ) {
 */
 
 void workScheduleSubmit( void* workUnit ) {
-  pthread_mutex_lock  ( &dequeLock );
+  pthread_mutex_lock  ( &systemLock );
   addNewItemBack      ( dequeWorkUnits, workUnit );
-  pthread_mutex_unlock( &dequeLock );
+  pthread_cond_signal( &workAvailCond );
+  pthread_mutex_unlock( &systemLock );
 }
 
 
@@ -287,9 +292,10 @@ void workScheduleBegin() {
   int i;
 
   // tell all workers to begin
-  pthread_mutex_lock    ( &systemBeginLock );
+  pthread_mutex_lock    ( &systemLock );
+  systemStarted = 1;
   pthread_cond_broadcast( &systemBeginCond );
-  pthread_mutex_unlock  ( &systemBeginLock );  
+  pthread_mutex_unlock  ( &systemLock );  
 
   for( i = 0; i < numWorkers; ++i ) {
     pthread_join( workerArray[i], NULL );