doc: dev-tools: kselftest.rst: Update examples and paths

Update the installation commands and path details, detail the new
options available in the run_kselftests.sh script.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Author: kees

Documentation/dev-tools/kselftest.rst

@@ -125,32 +125,41 @@ Note that some tests will require root privileges.
 Install selftests
 =================
 
-You can use the kselftest_install.sh tool to install selftests in the
-default location, which is tools/testing/selftests/kselftest, or in a
-user specified location.
+You can use the "install" target of "make" (which calls the `kselftest_install.sh`
+tool) to install selftests in the default location (`tools/testing/selftests/kselftest_install`),
+or in a user specified location via the `INSTALL_PATH` "make" variable.
 
 To install selftests in default location::
 
-   $ cd tools/testing/selftests
-   $ ./kselftest_install.sh
+   $ make -C tools/testing/selftests install
 
 To install selftests in a user specified location::
 
-   $ cd tools/testing/selftests
-   $ ./kselftest_install.sh install_dir
+   $ make -C tools/testing/selftests install INSTALL_PATH=/some/other/path
 
 Running installed selftests
 ===========================
 
-Kselftest install as well as the Kselftest tarball provide a script
-named "run_kselftest.sh" to run the tests.
+Found in the install directory, as well as in the Kselftest tarball,
+is a script named `run_kselftest.sh` to run the tests.
 
 You can simply do the following to run the installed Kselftests. Please
 note some tests will require root privileges::
 
-   $ cd kselftest
+   $ cd kselftest_install
    $ ./run_kselftest.sh
 
+To see the list of available tests, the `-l` option can be used::
+
+   $ ./run_kselftest.sh -l
+
+The `-c` option can be used to run all the tests from a test collection, or
+the `-t` option for specific single tests. Either can be used multiple times::
+
+   $ ./run_kselftest.sh -c bpf -c seccomp -t timers:posix_timers -t timer:nanosleep
+
+For other features see the script usage output, seen with the `-h` option.
+
 Packaging selftests
 ===================
 
@@ -160,9 +169,9 @@ different system. To package selftests, run::
    $ make -C tools/testing/selftests gen_tar
 
 This generates a tarball in the `INSTALL_PATH/kselftest-packages` directory. By
-default, `.gz` format is used. The tar format can be overridden by specifying
-a `FORMAT` make variable. Any value recognized by `tar's auto-compress`_ option
-is supported, such as::
+default, `.gz` format is used. The tar compression format can be overridden by
+specifying a `FORMAT` make variable. Any value recognized by `tar's auto-compress`_
+option is supported, such as::
 
     $ make -C tools/testing/selftests gen_tar FORMAT=.xz