kernel/linux.git/tools/testing/selftests/resctrl/mbm_test.c, branch v6.12.80

selftests/resctrl: Print accurate buffer size as part of MBM results

2024-12-05T13:01:33+00:00

[ Upstream commit 1b4840395f08e9723a15fea42c2d31090e8375f3 ] By default the MBM test uses the "fill_buf" benchmark to keep reading from a buffer with size DEFAULT_SPAN while measuring memory bandwidth. User space can provide an alternate benchmark or amend the size of the buffer "fill_buf" should use. Analysis of the MBM measurements do not require that a buffer be used and thus do not require knowing the size of the buffer if it was used during testing. Even so, the buffer size is printed as informational as part of the MBM test results. What is printed as buffer size is hardcoded as DEFAULT_SPAN, even if the test relied on another benchmark (that may or may not use a buffer) or if user space amended the buffer size. Ensure that accurate buffer size is printed when using "fill_buf" benchmark and omit the buffer size information if another benchmark is used. Fixes: ecdbb911f22d ("selftests/resctrl: Add MBM test") Signed-off-by: Reinette Chatre Reviewed-by: Ilpo Järvinen Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests/resctrl: Remove test name comparing from write_bm_pid_to_resctrl()

2024-07-11T17:23:54+00:00

write_bm_pid_to_resctrl() uses resctrl_val to check test name which is not a good interface generic resctrl FS functions should provide. Tests define mongrp when needed. Remove the test name check in write_bm_pid_to_resctrl() to only rely on the mongrp parameter being non-NULL. Remove write_bm_pid_to_resctrl() resctrl_val parameter and resctrl_val member from the struct resctrl_val_param that are not used anymore. Similarly, remove the test name constants that are no longer used. Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Simplify bandwidth report type handling

2024-07-11T17:23:54+00:00

bw_report is only needed for selecting the correct value from the values IMC measured. It is a member in the resctrl_val_param struct and is always set to "reads". The value is then checked in resctrl_val() using validate_bw_report_request() that besides validating the input, assumes it can mutate the string which is questionable programming practice. Simplify handling bw_report: - Convert validate_bw_report_request() into get_bw_report_type() that inputs and returns const char *. Use NULL to indicate error. - Validate the report types inside measure_mem_bw(), not in resctrl_val(). - Pass bw_report to measure_mem_bw() from ->measure() hook because resctrl_val() no longer needs bw_report for anything. Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Add ->init() callback into resctrl_val_param

2024-07-11T17:23:54+00:00

The struct resctrl_val_param is there to customize behavior inside resctrl_val() which is currently not used to full extent and there are number of strcmp()s for test name in resctrl_val done by resctrl_val(). Create ->init() hook into the struct resctrl_val_param to cleanly do per test initialization. Remove also unused branches to setup paths and the related #defines for CMT test. While touching kerneldoc, make the adjacent line consistent with the newly added form (callback vs call back). Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Add ->measure() callback to resctrl_val_param

2024-07-11T17:23:54+00:00

The measurement done in resctrl_val() varies depending on test type. The decision for how to measure is decided based on the string compare to test name which is quite inflexible. Add ->measure() callback into the struct resctrl_val_param to allow each test to provide necessary code as a function which simplifies what resctrl_val() has to do. Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM tests

2024-07-11T17:23:54+00:00

initialize_mem_bw_resctrl() and set_mbm_path() contain complicated set of conditions, each yielding different file to be opened to measure memory bandwidth through resctrl FS. In practice, only two of them are used. For MBA test, ctrlgrp is always provided, and for MBM test both ctrlgrp and mongrp are set. The file used differ between MBA/MBM test, however, MBM test unnecessarily create monitor group because resctrl FS already provides monitoring interface underneath any ctrlgrp too, which is what the MBA selftest uses. Consolidate memory bandwidth file used to the one used by the MBA selftest. Remove all unused branches opening other files to simplify the code. Suggested-by: Reinette Chatre Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: fix clang build warnings related to abs(), labs() calls

2024-05-08T22:53:19+00:00

When building with clang, via: make LLVM=1 -C tools/testing/selftests ...two types of warnings occur: warning: absolute value function 'abs' given an argument of type 'long' but has parameter of type 'int' which may cause truncation of value warning: taking the absolute value of unsigned type 'unsigned long' has no effect Fix these by: a) using labs() in place of abs(), when long integers are involved, and b) Change to use signed integer data types, in places where subtraction is used (and could end up with negative values). c) Remove a duplicate abs() call in cmt_test.c. Cc: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: John Hubbard Signed-off-by: Shuah Khan

selftests/resctrl: Move cleanups out of individual tests

2024-05-06T19:57:19+00:00

Every test calls its cleanup function at the end of it's test function. After the cleanup function pointer is added to the test framework this can be simplified to executing the callback function at the end of the generic test running function. Make test cleanup functions static and call them from the end of run_single_test() from the resctrl_test's cleanup function pointer. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Add cleanup function to test framework

2024-05-06T19:57:19+00:00

Resctrl selftests use very similar functions to cleanup after themselves. This creates a lot of code duplication. Also not being hooked to the test framework means that ctrl-c handler isn't aware of what test is currently running and executes all cleanups even though only one is needed. Add a function pointer to the resctrl_test struct and attach to it cleanup functions from individual tests. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Split validate_resctrl_feature_request()

2024-02-23T22:19:15+00:00

validate_resctrl_feature_request() is used to test both if a resource is present in the info directory, and if a passed monitoring feature is present in the mon_features file. Refactor validate_resctrl_feature_request() into two smaller functions that each accomplish one check to give feature checking more granularity: - Resource directory presence in the /sys/fs/resctrl/info directory. - Feature name presence in the /sys/fs/resctrl/info//mon_features file. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan