Address comments

Author: wangyum

sql/core/src/test/scala/org/apache/spark/sql/execution/benchmark/AggregateBenchmark.scala

@@ -47,19 +47,19 @@ object AggregateBenchmark extends SqlBasedBenchmark {
   override def benchmark(): Unit = {
     runBenchmark("aggregate without grouping") {
       val N = 500L << 22
-      runBenchmarkWithCodegen("agg w/o group", N) {
+      codegenBenchmark("agg w/o group", N) {
         spark.range(N).selectExpr("sum(id)").collect()
       }
     }
 
     runBenchmark("stat functions") {
       val N = 100L << 20
 
-      runBenchmarkWithCodegen("stddev", N) {
+      codegenBenchmark("stddev", N) {
         spark.range(N).groupBy().agg("id" -> "stddev").collect()
       }
 
-      runBenchmarkWithCodegen("kurtosis", N) {
+      codegenBenchmark("kurtosis", N) {
         spark.range(N).groupBy().agg("id" -> "kurtosis").collect()
       }
     }
@@ -313,7 +313,7 @@ object AggregateBenchmark extends SqlBasedBenchmark {
     runBenchmark("cube") {
       val N = 5 << 20
 
-      runBenchmarkWithCodegen("cube", N) {
+      codegenBenchmark("cube", N) {
         spark.range(N).selectExpr("id", "id % 1000 as k1", "id & 256 as k2")
           .cube("k1", "k2").sum("id").collect()
       }

sql/core/src/test/scala/org/apache/spark/sql/execution/benchmark/SqlBasedBenchmark.scala

@@ -27,7 +27,7 @@ import org.apache.spark.sql.internal.SQLConf
  */
 trait SqlBasedBenchmark extends BenchmarkBase with SQLHelper {
 
-  val spark: SparkSession = getSparkSession
+  protected val spark: SparkSession = getSparkSession
 
   /** Subclass can override this function to build their own SparkSession */
   def getSparkSession: SparkSession = {
@@ -40,7 +40,7 @@ trait SqlBasedBenchmark extends BenchmarkBase with SQLHelper {
   }
 
   /** Runs function `f` with whole stage codegen on and off. */
-  def runBenchmarkWithCodegen(name: String, cardinality: Long)(f: => Unit): Unit = {
+  final def codegenBenchmark(name: String, cardinality: Long)(f: => Unit): Unit = {
     val benchmark = new Benchmark(name, cardinality, output = output)
 
     benchmark.addCase(s"$name wholestage off", numIters = 2) { _ =>