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example/49_maxpool2d_bwd/maxpool2d_bwd_common.hpp

@@ -163,6 +163,8 @@ bool maxpool_bwd_test(bool do_verification,
 
     size_t pool_bwd_workspace_sz = pool_bwd.GetWorkSpaceSize(pool_bwd_argument_ptr.get());
     DeviceMem pool_bwd_workspace_device_buf(pool_bwd_workspace_sz);
+    // similar to din_device_buf.SetZero()
+    // we need to set workspace to be zero
     pool_bwd_workspace_device_buf.SetZero();
     pool_bwd.SetWorkSpacePointer(pool_bwd_argument_ptr.get(),
                                  pool_bwd_workspace_device_buf.GetDeviceBuffer());

include/ck/tensor_operation/gpu/device/impl/device_index_pool_bwd_impl.hpp

@@ -244,6 +244,7 @@ struct DeviceIndexPoolBwdImpl : public DeviceIndexPoolBwd<DOutDataType, IndexDat
         }
     };
 
+    // User need to set the value of workspace to zero
     size_t GetWorkSpaceSize(const BaseArgument* pArg) const override
     {
         const Argument* pArg_ = dynamic_cast<const Argument*>(pArg);