# HG changeset patch
# User Merten Sach <msach@mailbox.tu-berlin.de>
# Date 1328288229 -3600
# Node ID 91d0d2e06719395f9cd1d314af4b91f15ebe656e
# Parent  c66137e4dc2f65ebdfbee157987e95cf86544511
backoff won't be optimized out by gcc

diff -r c66137e4dc2f -r 91d0d2e06719 CoreLoop.c
--- a/CoreLoop.c	Fri Jan 13 11:49:05 2012 +0100
+++ b/CoreLoop.c	Fri Feb 03 17:57:09 2012 +0100
@@ -47,6 +47,8 @@
    int32           numMasterInARow = 0;
    volatile int32 *masterLock;
    VirtProcr      *masterVP;
+   
+   double         workspace1,workspace2; //variables for master lock busy waiting
 
    // init random number generator for retries
    uint32_t seed1 = rand()%1000;
@@ -141,11 +143,16 @@
       while( currVP == NULL ) //if queue was empty, enter get masterLock loop
        {    //queue was empty, so get master lock
 
-		 if(numMasterInARow > 2){
-		 	wait_iterations=(randomNumber(&seed1, &seed2) % (numMasterInARow*numMasterInARow))*100;
-	   		int i;
-	  	    for(i=0; i<wait_iterations; i++)/*busy wait*/;
-		 }
+	if(numMasterInARow > 2){
+                wait_iterations=(randomNumber(&seed1, &seed2) % (numMasterInARow*numMasterInARow))*100;
+	   	int i;
+	  	for(i=0; i<wait_iterations; i++)
+                {/*busy wait*/
+                    workspace1 += (workspace1 + 32)/2;
+                    workspace2 += (workspace2 + 23.2)/1.4;
+                }
+        }
+                 
          gotLock = __sync_bool_compare_and_swap(masterLock,
                                                 UNLOCKED, LOCKED );
          if( gotLock )
@@ -161,7 +168,11 @@
 	   wait_iterations=(randomNumber(&seed1, &seed2) % (tries+1))*100;
 	   //addToHist( wait_iterations, coreLoopThdParams->wait_iterations_hist );
 	   int i;
-	   for(i=0; i<wait_iterations; i++)/*busy wait*/;
+	   for(i=0; i<wait_iterations; i++)
+           {/*busy wait*/
+                workspace1 += (workspace1 + 32)/2;
+                workspace2 += (workspace2 + 23.2)/1.4;
+           }
 	}
 
          tries++;      //if too many, means master on other core taking too long
@@ -199,7 +210,9 @@
           _VMSMasterEnv->startMaster.longVal = endSusp.longVal;
           #endif
           //==================================================
-   }//CoreLoop      
+   }//CoreLoop
+   
+   return (workspace1 + workspace2); //gcc fake out for -O3
  }
 
 inline uint32_t
diff -r c66137e4dc2f -r 91d0d2e06719 MasterLoop.c
--- a/MasterLoop.c	Fri Jan 13 11:49:05 2012 +0100
+++ b/MasterLoop.c	Fri Feb 03 17:57:09 2012 +0100
@@ -106,7 +106,6 @@
    slaveScheduler   = masterEnv->slaveScheduler;
    semanticEnv      = masterEnv->semanticEnv;
    
-      //masterLoopStartPt:
    while(1){    //switch to core_loop and back to here is at end of loop
        
        //============================= MEASUREMENT STUFF =======================
@@ -120,10 +119,10 @@
 
 
       //Poll each slot's Done flag
-   numSlotsFilled = 0;
-   /*
+      numSlotsFilled = 0;
+      /*
          Meas_startMasterLoop
-    */
+      */
    for( slotIdx = 0; slotIdx < NUM_SCHED_SLOTS; slotIdx++)
     {
       currSlot = schedSlots[ slotIdx ];