linux/tools/testing/selftests/ftrace
Linus Torvalds e1fd0b2acd Second set of tracing updates for 5.16:
- osnoise and timerlat updates that will work with the RTLA tool (Real-Time
   Linux Analysis). Specifically it disconnects the work load (threads
   that look for latency) from the tracing instances attached to them,
   allowing for more than one instance to retrieve data from the work load.
 
 - Optimization on division in the trace histogram trigger code to use shift
   and multiply when possible. Also added documentation.
 
 - Fix prototype to my_direct_func in direct ftrace trampoline sample code.
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Merge tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull more tracing updates from Steven Rostedt:

 - osnoise and timerlat updates that will work with the RTLA tool
   (Real-Time Linux Analysis).

   Specifically it disconnects the work load (threads that look for
   latency) from the tracing instances attached to them, allowing for
   more than one instance to retrieve data from the work load.

 - Optimization on division in the trace histogram trigger code to use
   shift and multiply when possible. Also added documentation.

 - Fix prototype to my_direct_func in direct ftrace trampoline sample
   code.

* tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/samples: Add missing prototype for my_direct_func
  tracing/selftests: Add tests for hist trigger expression parsing
  tracing/histogram: Document hist trigger variables
  tracing/histogram: Update division by 0 documentation
  tracing/histogram: Optimize division by constants
  tracing/osnoise: Remove PREEMPT_RT ifdefs from inside functions
  tracing/osnoise: Remove STACKTRACE ifdefs from inside functions
  tracing/osnoise: Allow multiple instances of the same tracer
  tracing/osnoise: Remove TIMERLAT ifdefs from inside functions
  tracing/osnoise: Support a list of trace_array *tr
  tracing/osnoise: Use start/stop_per_cpu_kthreads() on osnoise_cpus_write()
  tracing/osnoise: Split workload start from the tracer start
  tracing/osnoise: Improve comments about barrier need for NMI callbacks
  tracing/osnoise: Do not follow tracing_cpumask
2021-11-03 09:08:47 -07:00
..
samples ftracetest: Add POSIX.3 standard and XFAIL result codes 2014-10-03 16:44:02 -04:00
test.d Second set of tracing updates for 5.16: 2021-11-03 09:08:47 -07:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
config selftests/ftrace: Add CONFIG_SAMPLE_FTRACE_DIRECT=m kconfig 2020-04-14 10:00:29 -06:00
ftracetest selftests/ftrace: Stop tracing while reading the trace file by default 2021-10-26 20:27:19 -04:00
Makefile selftests: Install settings files to fix TIMEOUT failures 2020-02-20 08:56:42 -07:00
README ftracetest: Add POSIX.3 standard and XFAIL result codes 2014-10-03 16:44:02 -04:00
settings tracing/selftests: Turn off timeout setting 2019-11-14 13:15:11 -05:00

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 :)