linux-stable/tools/testing/selftests/resctrl
Ilpo Järvinen 5247e6dbed selftests/resctrl: Fix MBM test failure when MBA unavailable
Commit 20d96b25cc ("selftests/resctrl: Fix schemata write error
check") exposed a problem in feature detection logic in MBM selftest.
If schemata does not support MB:x=x entries, the schemata write to
initialize 100% memory bandwidth allocation in mbm_setup() will now
fail with -EINVAL due to the error handling corrected by the commit
20d96b25cc ("selftests/resctrl: Fix schemata write error check").
That commit just uncovers the failed write, it is not wrong itself.

If MB:x=x is not supported by schemata, it is safe to assume 100%
memory bandwidth is always set. Therefore, the previously ignored error
does not make the MBM test itself wrong.

Restore the previous behavior of MBM test by checking MB support before
attempting to write it into schemata which results in behavior
equivalent to ignoring the write error.

Fixes: 20d96b25cc ("selftests/resctrl: Fix schemata write error check")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-10-18 14:33:44 -06:00
..
.gitignore selftests/resctrl: Create .gitignore to include resctrl_tests 2021-04-02 13:58:42 -06:00
Makefile selftests/resctrl: Move _GNU_SOURCE define into Makefile 2023-10-13 14:54:21 -06:00
README selftests/resctrl: Update README about using kselftest framework to build/run resctrl_tests 2022-04-25 17:11:41 -06:00
cache.c selftests/resctrl: Simplify span lifetime 2023-10-13 14:28:44 -06:00
cat_test.c selftests/resctrl: Extend signal handler coverage to unmount on receiving signal 2023-10-13 14:54:09 -06:00
cmt_test.c selftests/resctrl: Remove duplicate feature check from CMT test 2023-10-13 14:54:16 -06:00
config selftests/resctrl: Add config dependencies 2021-04-02 13:57:42 -06:00
fill_buf.c selftests/resctrl: Don't pass test name to fill_buf 2023-07-25 08:53:48 -06:00
mba_test.c selftests/resctrl: Reduce failures due to outliers in MBA/MBM tests 2023-10-13 14:54:38 -06:00
mbm_test.c selftests/resctrl: Fix MBM test failure when MBA unavailable 2023-10-18 14:33:44 -06:00
resctrl.h selftests/resctrl: Move run_benchmark() to a more fitting file 2023-10-13 14:59:06 -06:00
resctrl_tests.c selftests/resctrl: Fix feature checks 2023-10-13 14:54:34 -06:00
resctrl_val.c selftests/resctrl: Move run_benchmark() to a more fitting file 2023-10-13 14:59:06 -06:00
resctrlfs.c selftests/resctrl: Move run_benchmark() to a more fitting file 2023-10-13 14:59:06 -06:00
settings selftests/resctrl: Change the default limited time to 120 seconds 2022-04-25 17:06:53 -06:00

README

resctrl_tests - resctrl file system test suit

Authors:
	Fenghua Yu <fenghua.yu@intel.com>
	Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,

resctrl_tests tests various resctrl functionalities and interfaces including
both software and hardware.

Currently it supports Memory Bandwidth Monitoring test and Memory Bandwidth
Allocation test on Intel RDT hardware. More tests will be added in the future.
And the test suit can be extended to cover AMD QoS and ARM MPAM hardware
as well.

resctrl_tests can be run with or without kselftest framework.

WITH KSELFTEST FRAMEWORK
=======================

BUILD
-----

Build executable file "resctrl_tests" from top level directory of the kernel source:
 $ make -C tools/testing/selftests TARGETS=resctrl

RUN
---

Run resctrl_tests as sudo or root since the test needs to mount resctrl file
system and change contents in the file system.
Using kselftest framework will run all supported tests within resctrl_tests:

 $ sudo make -C tools/testing/selftests TARGETS=resctrl run_tests

More details about kselftest framework can be found in
Documentation/dev-tools/kselftest.rst.

WITHOUT KSELFTEST FRAMEWORK
===========================

BUILD
-----

Build executable file "resctrl_tests" from this directory(tools/testing/selftests/resctrl/):
  $ make

RUN
---

Run resctrl_tests as sudo or root since the test needs to mount resctrl file
system and change contents in the file system.
Executing the test without any parameter will run all supported tests:

 $ sudo ./resctrl_tests

OVERVIEW OF EXECUTION
=====================

A test case has four stages:

  - setup: mount resctrl file system, create group, setup schemata, move test
    process pids to tasks, start benchmark.
  - execute: let benchmark run
  - verify: get resctrl data and verify the data with another source, e.g.
    perf event.
  - teardown: umount resctrl and clear temporary files.

ARGUMENTS
=========

Parameter '-h' shows usage information.

usage: resctrl_tests [-h] [-b "benchmark_cmd [options]"] [-t test list] [-n no_of_bits]
        -b benchmark_cmd [options]: run specified benchmark for MBM, MBA and CMT default benchmark is builtin fill_buf
        -t test list: run tests specified in the test list, e.g. -t mbm,mba,cmt,cat
        -n no_of_bits: run cache tests using specified no of bits in cache bit mask
        -p cpu_no: specify CPU number to run the test. 1 is default
        -h: help