Expose stream-ordering in public transpose API

cpp/include/cudf/transpose.hpp

@@ -36,14 +36,16 @@ namespace CUDF_EXPORT cudf {
  * @throw cudf::logic_error if column types are non-homogeneous
  * @throw cudf::logic_error if column types are non-fixed-width
  *
- * @param[in] input A table (M cols x N rows) to be transposed
- * @param[in] mr Device memory resource used to allocate the device memory of returned value
- * @return          The transposed input (N cols x M rows) as a `column` and
- *                  `table_view`, representing the owner and transposed table,
- *                  respectively.
+ * @param[in] input   A table (M cols x N rows) to be transposed
+ * @param[in] stream  CUDA stream used for device memory operations and kernel launches
+ * @param[in] mr      Device memory resource used to allocate the device memory of returned value
+ * @return            The transposed input (N cols x M rows) as a `column` and
+ *                    `table_view`, representing the owner and transposed table,
+ *                    respectively.
  */
 std::pair<std::unique_ptr<column>, table_view> transpose(
   table_view const& input,
+  rmm::cuda_stream_view stream      = cudf::get_default_stream(),
   rmm::device_async_resource_ref mr = cudf::get_current_device_resource_ref());
 
 /** @} */  // end of group

cpp/src/transpose/transpose.cu

@@ -61,10 +61,11 @@ std::pair<std::unique_ptr<column>, table_view> transpose(table_view const& input
 }  // namespace detail
 
 std::pair<std::unique_ptr<column>, table_view> transpose(table_view const& input,
+                                                         rmm::cuda_stream_view stream,
                                                          rmm::device_async_resource_ref mr)
 {
   CUDF_FUNC_RANGE();
-  return detail::transpose(input, cudf::get_default_stream(), mr);
+  return detail::transpose(input, stream, mr);
 }
 
 }  // namespace cudf

cpp/tests/CMakeLists.txt

@@ -749,6 +749,7 @@ ConfigureTest(
   testing
 )
 ConfigureTest(STREAM_TRANSFORM_TEST streams/transform_test.cpp STREAM_MODE testing)
+ConfigureTest(STREAM_TRANSPOSE_TEST streams/transpose_test.cpp STREAM_MODE testing)
 ConfigureTest(STREAM_UNARY_TEST streams/unary_test.cpp STREAM_MODE testing)
 
 # ##################################################################################################

cpp/tests/streams/transpose_test.cpp

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2024, NVIDIA CORPORATION.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <cudf_test/base_fixture.hpp>
+#include <cudf_test/column_utilities.hpp>
+#include <cudf_test/column_wrapper.hpp>
+#include <cudf_test/default_stream.hpp>
+#include <cudf_test/testing_main.hpp>
+
+#include <cudf/transpose.hpp>
+
+#include <algorithm>
+#include <random>
+#include <string>
+
+class TransposeTest : public cudf::test::BaseFixture {};
+
+TEST_F(TransposeTest, StringTest)
+{
+  using ColumnWrapper = cudf::test::strings_column_wrapper;
+  size_t ncols        = 10;
+  size_t nrows        = 10;
+
+  std::mt19937 rng(1);
+
+  auto const values = [&rng, nrows, ncols]() {
+    std::vector<std::vector<std::string>> values(ncols);
+    std::for_each(values.begin(), values.end(), [&rng, nrows](std::vector<std::string>& col) {
+      col.resize(nrows);
+      std::generate(col.begin(), col.end(), [&rng]() { return std::to_string(rng()); });
+    });
+    return values;
+  }();
+
+  auto input_cols = [&values]() {
+    std::vector<ColumnWrapper> columns;
+    columns.reserve(values.size());
+    for (auto const& value_col : values) {
+      columns.emplace_back(value_col.begin(), value_col.end());
+    }
+    return columns;
+  }();
+
+  auto input_view = [&input_cols]() {
+    std::vector<cudf::column_view> views(input_cols.size());
+    std::transform(input_cols.begin(), input_cols.end(), views.begin(), [](auto const& col) {
+      return static_cast<cudf::column_view>(col);
+    });
+    return cudf::table_view(views);
+  }();
+
+  auto result = transpose(input_view, cudf::test::get_default_stream());
+}
+
+CUDF_TEST_PROGRAM_MAIN()