mirror_ubuntu-kernels/tools/testing/selftests/resctrl
Fenghua Yu 06bd03a57f selftests/resctrl: Fix MBA/MBM results reporting format
MBM unit test starts fill_buf (default built-in benchmark) in a new con_mon
group (c1, m1) and records resctrl reported mbm values and iMC (Integrated
Memory Controller) values every second. It does this for five seconds
(randomly chosen value) in total. It then calculates average of resctrl_mbm
values and imc_mbm values and if the difference is greater than 300 MB/sec
(randomly chosen value), the test treats it as a failure. MBA unit test is
similar to MBM but after every run it changes schemata.

Checking for a difference of 300 MB/sec doesn't look very meaningful when
the mbm values are changing over a wide range. For example, below are the
values running MBA test on SKL with different allocations

1. With 10% as schemata both iMC and resctrl mbm_values are around 2000
   MB/sec
2. With 100% as schemata both iMC and resctrl mbm_values are around 10000
   MB/sec

A 300 MB/sec difference between resctrl_mbm and imc_mbm values is
acceptable at 100% schemata but it isn't acceptable at 10% schemata because
that's a huge difference.

So, fix this by checking for percentage difference instead of absolute
difference i.e. check if the difference between resctrl_mbm value and
imc_mbm value is within 5% (randomly chosen value) of imc_mbm value. If the
difference is greater than 5% of imc_mbm value, treat it is a failure.

Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-04-02 13:58:02 -06:00
..
cache.c selftests/resctrl: Share show_cache_info() by CAT and CMT tests 2021-04-02 13:54:14 -06:00
cat_test.c selftests/resctrl: Share show_cache_info() by CAT and CMT tests 2021-04-02 13:54:14 -06:00
cmt_test.c selftests/resctrl: Share show_cache_info() by CAT and CMT tests 2021-04-02 13:54:14 -06:00
config selftests/resctrl: Add config dependencies 2021-04-02 13:57:42 -06:00
fill_buf.c selftests/resctrl: Clean up resctrl features check 2021-04-02 13:51:36 -06:00
Makefile selftests/resctrl: Enable gcc checks to detect buffer overflows 2021-04-02 13:51:16 -06:00
mba_test.c selftests/resctrl: Fix MBA/MBM results reporting format 2021-04-02 13:58:02 -06:00
mbm_test.c selftests/resctrl: Fix MBA/MBM results reporting format 2021-04-02 13:58:02 -06:00
README selftests/resctrl: Rename CQM test as CMT test 2021-04-02 13:53:54 -06:00
resctrl_tests.c selftests/resctrl: Fix a printed message 2021-04-02 13:54:20 -06:00
resctrl_val.c selftests/resctrl: Call kselftest APIs to log test results 2021-04-02 13:54:08 -06:00
resctrl.h selftests/resctrl: Use resctrl/info for feature detection 2021-04-02 13:57:57 -06:00
resctrlfs.c selftests/resctrl: Use resctrl/info for feature detection 2021-04-02 13:57:57 -06:00

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.

BUILD
-----

Run "make" to build executable file "resctrl_tests".

RUN
---

To use resctrl_tests, root or sudoer privileges are required. This is because
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