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Commit20d96b25cc("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 commit20d96b25cc("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>
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