P4 to Git Change 1122235 by xcui@merged_opencl_jxcwin on 2015/02/13 17:28:52

EPR #413091 - move commit svm host memory into allocmaptarget and added hostmemref as the backing store  for multiple gpu cases

Affected files ...

... //depot/stg/opencl/drivers/opencl/api/opencl/amdocl/cl_memobj.cpp#73 edit
... //depot/stg/opencl/drivers/opencl/api/opencl/amdocl/cl_svm.cpp#11 edit
... //depot/stg/opencl/drivers/opencl/runtime/device/gpu/gpukernel.cpp#280 edit
... //depot/stg/opencl/drivers/opencl/runtime/device/gpu/gpumemory.cpp#118 edit
... //depot/stg/opencl/drivers/opencl/runtime/platform/memory.cpp#115 edit

rocclr/runtime/platform/memory.cpp

@@ -251,7 +251,7 @@ Memory::allocHostMemory(void* initFrom, bool allocHostMem, bool forceCopy)
         pipe->end_idx = asPipe()->getMaxNumPackets();
     }
 
-    if (flags_ & (CL_MEM_USE_HOST_PTR | CL_MEM_COPY_HOST_PTR)) {
+    if ((flags_ & (CL_MEM_USE_HOST_PTR | CL_MEM_COPY_HOST_PTR)) && (NULL == lastWriter_)) {
         // Signal write, so coherency mechanism will initialize
         // memory on all devices
         signalWrite(NULL);