linux/tools/testing/selftests/resctrl/resctrlfs.c, branch v6.7

selftests/resctrl: Move run_benchmark() to a more fitting file

2023-10-13T20:59:06Z

resctrlfs.c contains mostly functions that interact in some way with resctrl FS entries while functions inside resctrl_val.c deal with measurements and benchmarking. run_benchmark() is located in resctrlfs.c even though it's purpose is not interacting with the resctrl FS but to execute cache checking logic. Move run_benchmark() to resctrl_val.c just before resctrl_val() that makes use of run_benchmark(). Make run_benchmark() static since it's not used between multiple files anymore. Remove return comment from kernel-doc since the function is type void. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Fix schemata write error check

2023-10-13T20:59:01Z

Writing bitmasks to the schemata can fail when the bitmask doesn't adhere to constraints defined by what a particular CPU supports. Some example of constraints are max length or having contiguous bits. The driver should properly return errors when any rule concerning bitmask format is broken. Resctrl FS returns error codes from fprintf() only when fclose() is called. Current error checking scheme allows invalid bitmasks to be written into schemata file and the selftest doesn't notice because the fclose() error code isn't checked. Substitute fopen(), flose() and fprintf() with open(), close() and write() to avoid error code buffering between fprintf() and fclose(). Remove newline character from the schema string after writing it to the schemata file so it prints correctly before function return. Pass the string generated with strerror() to the "reason" buffer so the error message is more verbose. Extend "reason" buffer so it can hold longer messages. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Refactor feature check to use resource and feature name

2023-10-13T20:54:27Z

Feature check in validate_resctrl_feature_request() takes in the test name string and maps that to what to check per test. Pass resource and feature names to validate_resctrl_feature_request() directly rather than deriving them from the test name inside the function which makes the feature check easier to extend for new test cases. Use !! in the return statement to make the boolean conversion more obvious even if it is not strictly necessary from correctness point of view (to avoid it looking like the function is returning a freed pointer). Signed-off-by: Ilpo Järvinen Tested-by: Shaopeng Tan Reviewed-by: Reinette Chatre Reviewed-by: Shaopeng Tan Cc: # selftests/resctrl: Remove duplicate feature check from CMT test Cc: # selftests/resctrl: Move _GNU_SOURCE define into Makefile Signed-off-by: Shuah Khan

selftests/resctrl: Don't pass test name to fill_buf

2023-07-25T14:53:48Z

Test name is passed to fill_buf functions so that they can loop around buffer only once. This is required for CAT test case. To loop around buffer only once, caller doesn't need to let fill_buf know which test case it is. Instead, pass a boolean argument 'once' which makes fill_buf more generic. As run_benchmark() no longer needs to pass the test name to run_fill_buf(), a few test running functions can be simplified to not write the test name into the default benchmark_cmd. The has_ben argument can also be removed now from those test running functions. Co-developed-by: Fenghua Yu Signed-off-by: Fenghua Yu Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan

selftests/resctrl: Remove "malloc_and_init_memory" param from run_fill_buf()

2023-07-25T14:53:29Z

run_fill_buf()'s malloc_and_init_memory parameter is always 1. There's also duplicated memory init code for malloc_and_init_memory == 0 case in fill_buf() which is unused. Remove the malloc_and_init_memory parameter and the duplicated mem init code. While at it, fix also a typo in run_fill_buf() prototype's argument. Co-developed-by: Fenghua Yu Signed-off-by: Fenghua Yu Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan

selftests/resctrl: Express span internally in bytes

2023-07-25T14:53:18Z

MBA and MBM tests to use megabytes to represent span. CMT test uses bytes. The difference requires run_benchmark() to size the buffer differently based on the test name, which in turn requires passing the test name into run_benchmark(). Convert MBA and MBM tests to use span internally in bytes like CMT test to remove the internal inconsistency between the tests. Remove the test dependent buffer sizing from run_benchmark(). This change eliminates one of the reasons why the test name has to be passed around but there are still other users too so the test name passing cannot yet be removed. Co-developed-by: Fenghua Yu Signed-off-by: Fenghua Yu Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan

selftests/resctrl: Convert span to size_t

2023-07-25T14:53:13Z

Span is defined either as unsigned long or int. Consistently use size_t everywhere for span as it refers to size of the memory block. Co-developed-by: Fenghua Yu Signed-off-by: Fenghua Yu Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan

selftests/resctrl: Refactor remount_resctrl(bool mum_resctrlfs) to mount_resctrl()

2023-07-25T14:53:00Z

Mount/umount of the resctrl FS is now paired nicely per test. Rename remount_resctrl(bool mum_resctrlfs) to mount_resctrl(). Make it unconditionally try to mount the resctrl FS and return error if resctrl FS was mounted already. While at it, group the mount/umount prototypes in the header. Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan

selftests/resctrl: Move resctrl FS mount/umount to higher level

2023-07-25T14:52:54Z

A few places currently lack umounting resctrl FS on error paths: - cmt_resctrl_val() has multiple error paths with direct return. - cat_perf_miss_val() has multiple error paths with direct return. In addition, validate_resctrl_feature_request() is called by run_mbm_test() and run_mba_test(). Neither MBA nor MBM test tries to umount resctrl FS. Each and every test does require resctrl FS to be present already for feature check. Thus, it makes sense to just mount it on higher level in resctrl_tests.c and properly pair it with umount. Move resctrl FS (re)mount/unmount into each test function in resctrl_tests.c. Make feature validation to simply check that resctrl FS is mounted. As there's the final umount in main() before this change, the selftest should not leave resctrl FS behind after the tests even if one of the forementioned paths is taken (thus, no fixes tag). Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan

selftests/resctrl: Unmount resctrl FS before starting the first test

2023-07-25T14:52:33Z

Resctrl FS mount/remount/umount code is hard to track. Better approach is to use mount/umount pair for each test but that assumes resctrl FS is not mounted beforehand. Change umount_resctrlfs() so that it can unmount resctrl FS from any path, and enable further simplifications into mount/remount/umount logic by unmounting resctrl FS at the start if a pre-existing mountpoint is found. Suggested-by: Reinette Chatre Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Tested-by: Shaopeng Tan (Fujitsu) Signed-off-by: Shuah Khan