Xiao Yang f0c0d0cf59 selftests/ftrace: Check the first record for kprobe_args_type.tc
It is possible to get multiple records from trace during test and then more
than 4 arguments are assigned to ARGS.  This situation results in the failure
of kprobe_args_type.tc.  For example:
-----------------------------------------------------------
grep testprobe trace
   ftracetest-5902  [001] d... 111195.682227: testprobe: (_do_fork+0x0/0x460) arg1=334823024 arg2=334823024 arg3=0x13f4fe70 arg4=7
     pmlogger-5949  [000] d... 111195.709898: testprobe: (_do_fork+0x0/0x460) arg1=345308784 arg2=345308784 arg3=0x1494fe70 arg4=7
 grep testprobe trace
 sed -e 's/.* arg1=\(.*\) arg2=\(.*\) arg3=\(.*\) arg4=\(.*\)/\1 \2 \3 \4/'
ARGS='334823024 334823024 0x13f4fe70 7
345308784 345308784 0x1494fe70 7'
-----------------------------------------------------------

We don't care which process calls do_fork so just check the first record to
fix the issue.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-04-24 09:39:26 -06:00
..

Linux Ftrace Testcases

This is a collection of testcases for ftrace tracing feature in the Linux
kernel. Since ftrace exports interfaces via the debugfs, we just need
shell scripts for testing. Feel free to add new test cases.

Running the ftrace testcases
============================

At first, you need to be the root user to run this script.
To run all testcases:

  $ sudo ./ftracetest

To run specific testcases:

  # ./ftracetest test.d/basic3.tc

Or you can also run testcases under given directory:

  # ./ftracetest test.d/kprobe/

Contributing new testcases
==========================

Copy test.d/template to your testcase (whose filename must have *.tc
extension) and rewrite the test description line.

 * The working directory of the script is <debugfs>/tracing/.

 * Take care with side effects as the tests are run with root privilege.

 * The tests should not run for a long period of time (more than 1 min.)
   These are to be unit tests.

 * You can add a directory for your testcases under test.d/ if needed.

 * The test cases should run on dash (busybox shell) for testing on
   minimal cross-build environments.

 * Note that the tests are run with "set -e" (errexit) option. If any
   command fails, the test will be terminated immediately.

 * The tests can return some result codes instead of pass or fail by
   using exit_unresolved, exit_untested, exit_unsupported and exit_xfail.

Result code
===========

Ftracetest supports following result codes.

 * PASS: The test succeeded as expected. The test which exits with 0 is
         counted as passed test.

 * FAIL: The test failed, but was expected to succeed. The test which exits
         with !0 is counted as failed test.

 * UNRESOLVED: The test produced unclear or intermidiate results.
             for example, the test was interrupted
                       or the test depends on a previous test, which failed.
                       or the test was set up incorrectly
             The test which is in above situation, must call exit_unresolved.

 * UNTESTED: The test was not run, currently just a placeholder.
             In this case, the test must call exit_untested.

 * UNSUPPORTED: The test failed because of lack of feature.
               In this case, the test must call exit_unsupported.

 * XFAIL: The test failed, and was expected to fail.
          To return XFAIL, call exit_xfail from the test.

There are some sample test scripts for result code under samples/.
You can also run samples as below:

  # ./ftracetest samples/

TODO
====

 * Fancy colored output :)