selftests/user_events: Test multi-format events

User_events now has multi-format events which allow for the same
register name, but with different formats. When this occurs, different
tracepoints are created with unique names.

Add a new test that ensures the same name can be used for two different
formats. Ensure they are isolated from each other and that name and arg
matching still works if yet another register comes in with the same
format as one of the two.

Link: https://lore.kernel.org/linux-trace-kernel/20240222001807.1463-4-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

selftests/user_events: Test persist flag cases

Now that we have exposed USER_EVENT_REG_PERSIST events can persist both
via the ABI and in the /sys/kernel/tracing/dynamic_events file.

Ensure both the ABI and DYN cases work by calling both during the parse
tests. Add new flags test that ensures only USER_EVENT_REG_PERSIST is
honored and any other flag is invalid.

Link: https://lkml.kernel.org/r/20230912180704.1284-3-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

selftests/user_events: Fix abi_test for BE archs

The abi_test currently uses a long sized test value for enablement
checks. On LE this works fine, however, on BE this results in inaccurate
assert checks due to a bit being used and assuming it's value is the
same on both LE and BE.

Use int type for 32-bit values and long type for 64-bit values to ensure
appropriate behavior on both LE and BE.

Fixes: 60b1af8de8c1 ("tracing/user_events: Add ABI self-test")
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests/user_events: Fix to unmount tracefs when test created mount

Fix to unmount tracefs if the self-test mounted it to allow testing.
If tracefs was already mounted, this does nothing.

Suggested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/all/29fce076-746c-4650-8358-b4e0fa215cf7@sirena.org.uk/
Fixes: a06023a8f78d ("selftests/user_events: Fix failures when user_events is not installed")

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests/user_events: Fix failures when user_events is not installed

When user_events is not installed the self tests currently fail. Now
that these self tests run by default we need to ensure they don't fail
when user_events was not enabled for the kernel being tested.

Add common methods to detect if tracefs and user_events is enabled. If
either is not enabled skip the test. If tracefs is enabled, but is not
mounted, mount tracefs and fail if there were any errors. Fail if not
run as root.

Fixes: 68b4d2d58389 ("selftests/user_events: Reenable build")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Link: https://lore.kernel.org/all/CA+G9fYuugZ0OMeS6HvpSS4nuf_A3s455ecipGBvER0LJHojKZg@mail.gmail.com/

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tracing/user_events: Ensure bit is cleared on unregister

If an event is enabled and a user process unregisters user_events, the
bit is left set. Fix this by always clearing the bit in the user process
if unregister is successful.

Update abi self-test to ensure this occurs properly.

Link: https://lkml.kernel.org/r/20230425225107.8525-3-beaub@linux.microsoft.com

Suggested-by: Doug Cook <dcook@linux.microsoft.com>
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

tracing/user_events: Add ABI self-test

Add ABI specific self-test to ensure enablements work in various
scenarios such as fork, VM_CLONE, and basic event enable/disable.
Ensure ABI contracts/limits are also being upheld, such as bit limits
and data size limits.

Link: https://lkml.kernel.org/r/20230328235219.203-8-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>