code: public double getAccumulatedExecutionTime() {
        KernelProfile profile = KernelManager.instance().getProfile(getClass());
        synchronized (profile) {
           return profile.getAccumulatedTotalTime();
        }
     }
docs: Determine the total execution time of all previous Kernel.execute(range) calls for all threads
  that ran this kernel for the device used in the last kernel execution.
  <br/>
  <b>Note1: </b>This is kept for backwards compatibility only, usage of
  {@link #getAccumulatedExecutionTimeAllThreads(Device)} is encouraged instead.<br/>
  <b>Note2: </b>Calling this method is not recommended when using more than a single thread to execute
  the same kernel on multiple devices concurrently.<br/>
  <br/>
  Note that this will include the initial conversion time.
  
  @return <ul><li>The total time spent executing the kernel (ms)</li>
  <li>NaN, if no profiling information is available</li></ul>
  
  @see #getAccumulatedExecutionTime(Device));
  @see #getProfileReport(Device)
  @see #registerProfileReportObserver(IProfileReportObserver)
  
  @see #getExecutionTime();
  @see #getConversionTime();