doc: extend instructions on benchdnn validation

Author: dzarukin

CONTRIBUTING.md

@@ -137,7 +137,17 @@ following information:
 oneDNN uses gtests for lightweight functional testing and benchdnn for
 performance and functional testing.
 
-Be sure to extend the existing tests when fixing an issue.
+Verify the modified code is covered by existing tests. If not, update the
+coverage to validate the change and sumbit it as a part of the PR.
 
-Developing new benchdnn tests can be hard, so it is a good idea to start with
-gtests first.
+Use the following command to run tests selected by a build configuration:
+``` sh
+    ctest
+```
+
+To modify the coverage, use the
+[`ONEDNN_TEST_SET`](https://oneapi-src.github.io/oneDNN/dev_guide_build_options.html#onednn-test-set)
+build option.
+
+More details on how to run benchdnn can be found in
+[benchdnn documentation](tests/benchdnn/doc/benchdnn_general_info.md#running-tests).

tests/benchdnn/doc/benchdnn_general_info.md

@@ -16,18 +16,18 @@ Returns `1` if any submitted tests returned status `FAILED` or `UNIMPLEMENTED`,
 
 ## Running Tests
 
-oneDNN comes with its own testing infrastructure enabled through CMake. Tests
-can be executed via the command:
+oneDNN comes with its own testing infrastructure enabled through CMake.
+If the project is built with `DNNL_BUILD_TESTS` set to `TRUE`, then Cmake will
+add test targets automatically.
+Targets can be triggered by the following command:
 ``` sh
-    make test_<test-name>
+    ctest [-R ".*benchdnn.*"]
 ```
-This instructs CMake to build a deployable project and run the specific test.
-
-These tests target specific oneDNN features and are based on benchdnn
-configurable executions.
+, where the content in brackets is optional and limits testing to benchdnn only.
+The pattern can be extended further for finer granularity.
 
 The available tests can be found in the oneDNN directory:
-tests/benchdnn/inputs/<driver>/<test-name>.
+tests/benchdnn/inputs/
 
 ## Glossary