Expose stream-ordering in subword tokenizer API (rapidsai#17206)

Add stream parameter to public APIs:
```
nvtext::subword_tokenize
nvtext::load_vocabulary_file
```
Added stream gtest.

Reference: rapidsai#13744

Authors:
  - Shruti Shivakumar (https://github.com/shrshi)
  - Muhammad Haseeb (https://github.com/mhaseeb123)

Approvers:
  - Nghia Truong (https://github.com/ttnghia)
  - David Wendt (https://github.com/davidwendt)
  - Muhammad Haseeb (https://github.com/mhaseeb123)

URL: rapidsai#17206

cpp/include/nvtext/subword_tokenize.hpp

@@ -62,11 +62,13 @@ struct hashed_vocabulary {
  * @param filename_hashed_vocabulary A path to the preprocessed vocab.txt file.
  *        Note that this is the file AFTER python/perfect_hash.py has been used
  *        for preprocessing.
+ * @param stream CUDA stream used for device memory operations and kernel launches
  * @param mr Memory resource to allocate any returned objects.
  * @return vocabulary hash-table elements
  */
 std::unique_ptr<hashed_vocabulary> load_vocabulary_file(
   std::string const& filename_hashed_vocabulary,
+  rmm::cuda_stream_view stream      = cudf::get_default_stream(),
   rmm::device_async_resource_ref mr = cudf::get_current_device_resource_ref());
 
 /**
@@ -147,6 +149,7 @@ struct tokenizer_result {
  * @param do_truncate If true, the tokenizer will discard all the token-ids after
  *        `max_sequence_length` for each input string. If false, it will use a new row
  *        in the output token-ids to continue generating the output.
+ * @param stream CUDA stream used for device memory operations and kernel launches
  * @param mr Memory resource to allocate any returned objects.
  * @return token-ids, attention-mask, and metadata
  */
@@ -157,6 +160,7 @@ tokenizer_result subword_tokenize(
   uint32_t stride,
   bool do_lower_case,
   bool do_truncate,
+  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/text/subword/load_hash_file.cu

@@ -289,10 +289,12 @@ std::unique_ptr<hashed_vocabulary> load_vocabulary_file(
 }  // namespace detail
 
 std::unique_ptr<hashed_vocabulary> load_vocabulary_file(
-  std::string const& filename_hashed_vocabulary, rmm::device_async_resource_ref mr)
+  std::string const& filename_hashed_vocabulary,
+  rmm::cuda_stream_view stream,
+  rmm::device_async_resource_ref mr)
 {
   CUDF_FUNC_RANGE();
-  return detail::load_vocabulary_file(filename_hashed_vocabulary, cudf::get_default_stream(), mr);
+  return detail::load_vocabulary_file(filename_hashed_vocabulary, stream, mr);
 }
 
 }  // namespace nvtext

cpp/src/text/subword/subword_tokenize.cu

@@ -293,17 +293,12 @@ tokenizer_result subword_tokenize(cudf::strings_column_view const& strings,
                                   uint32_t stride,
                                   bool do_lower_case,
                                   bool do_truncate,
+                                  rmm::cuda_stream_view stream,
                                   rmm::device_async_resource_ref mr)
 {
   CUDF_FUNC_RANGE();
-  return detail::subword_tokenize(strings,
-                                  vocabulary_table,
-                                  max_sequence_length,
-                                  stride,
-                                  do_lower_case,
-                                  do_truncate,
-                                  cudf::get_default_stream(),
-                                  mr);
+  return detail::subword_tokenize(
+    strings, vocabulary_table, max_sequence_length, stride, do_lower_case, do_truncate, stream, mr);
 }
 
 }  // namespace nvtext

cpp/tests/CMakeLists.txt

@@ -743,6 +743,7 @@ ConfigureTest(
   streams/text/ngrams_test.cpp
   streams/text/replace_test.cpp
   streams/text/stemmer_test.cpp
+  streams/text/subword_tokenize_test.cpp
   streams/text/tokenize_test.cpp
   STREAM_MODE
   testing

cpp/tests/streams/text/subword_tokenize_test.cpp

@@ -0,0 +1,81 @@
+/*
+ * 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/column/column.hpp>
+#include <cudf/strings/strings_column_view.hpp>
+
+#include <nvtext/subword_tokenize.hpp>
+
+#include <fstream>
+#include <vector>
+
+// Global environment for temporary files
+auto const temp_env = static_cast<cudf::test::TempDirTestEnvironment*>(
+  ::testing::AddGlobalTestEnvironment(new cudf::test::TempDirTestEnvironment));
+
+struct TextSubwordTest : public cudf::test::BaseFixture {};
+
+// Create a fake hashed vocab text file for the tests in this source file.
+// The vocab only includes the following words:
+//  'this', 'is', 'a', 'test', 'tést'
+// The period '.' character also has a token id.
+void create_hashed_vocab(std::string const& hash_file)
+{
+  constexpr size_t coefsize = 23;
+  std::vector<std::pair<int, int>> coefficients(coefsize, {65559, 0});
+  std::ofstream outfile(hash_file, std::ofstream::out);
+  outfile << "1\n0\n" << coefficients.size() << "\n";
+  for (auto c : coefficients) {
+    outfile << c.first << " " << c.second << "\n";
+  }
+  std::vector<uint64_t> hash_table(coefsize, 0);
+  outfile << hash_table.size() << "\n";
+  hash_table[0]  = 3015668L;              // based on values
+  hash_table[1]  = 6205475701751155871L;  // from the
+  hash_table[5]  = 6358029;               // bert_hash_table.txt
+  hash_table[16] = 451412625363L;         // file for the test
+  hash_table[20] = 6206321707968235495L;  // words above
+  for (auto h : hash_table) {
+    outfile << h << "\n";
+  }
+  outfile << "100\n101\n102\n\n";
+}
+
+TEST(TextSubwordTest, Tokenize)
+{
+  uint32_t const nrows = 100;
+  std::vector<char const*> h_strings(nrows, "This is a test. A test this is.");
+  cudf::test::strings_column_wrapper strings(h_strings.cbegin(), h_strings.cend());
+  std::string const hash_file = temp_env->get_temp_filepath("hashed_vocab.txt");
+  create_hashed_vocab(hash_file);
+  auto vocab = nvtext::load_vocabulary_file(hash_file, cudf::test::get_default_stream());
+
+  uint32_t const max_sequence_length = 16;
+  uint32_t const stride              = 16;
+
+  auto result = nvtext::subword_tokenize(cudf::strings_column_view{strings},
+                                         *vocab,
+                                         max_sequence_length,
+                                         stride,
+                                         true,   // do_lower_case
+                                         false,  // do_truncate
+                                         cudf::test::get_default_stream());
+}