linux/tools/testing/selftests/resctrl/resctrl_val.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: Extend signal handler coverage to unmount on receiving signal

2023-10-13T20:54:09Z

Unmounting resctrl FS has been moved into the per test functions in resctrl_tests.c by commit caddc0fbe495 ("selftests/resctrl: Move resctrl FS mount/umount to higher level"). In case a signal (SIGINT, SIGTERM, or SIGHUP) is received, the running selftest is aborted by ctrlc_handler() which then unmounts resctrl fs before exiting. The current section between signal_handler_register() and signal_handler_unregister(), however, does not cover the entire duration when resctrl FS is mounted. Move signal_handler_register() and signal_handler_unregister() calls from per test files into resctrl_tests.c to properly unmount resctrl fs. In order to not add signal_handler_register()/unregister() n times, create helpers test_prepare() and test_cleanup(). Do not call ksft_exit_fail_msg() in test_prepare() but only in the per test function to keep the control flow cleaner without adding calls to exit() deep into the call chain. Adjust child process kill() call in ctrlc_handler() to only be invoked if the child was already forked. Fixes: caddc0fbe495 ("selftests/resctrl: Move resctrl FS mount/umount to higher level") Signed-off-by: Ilpo Järvinen Tested-by: Shaopeng Tan Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Cc: Signed-off-by: Shuah Khan

selftests/resctrl: Fix uninitialized .sa_flags

2023-10-13T20:54:04Z

signal_handler_unregister() calls sigaction() with uninitializing sa_flags in the struct sigaction. Make sure sa_flags is always initialized in signal_handler_unregister() by initializing the struct sigaction when declaring it. Also add the initialization to signal_handler_register() even if there are no know bugs in there because correctness is then obvious from the code itself. Fixes: 73c55fa5ab55 ("selftests/resctrl: Commonize the signal handler register/unregister for all tests") Suggested-by: Reinette Chatre Signed-off-by: Ilpo Järvinen Cc: Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Make benchmark command const and build it with pointers

2023-10-13T20:28:55Z

Benchmark command is used in multiple tests so it should not be mutated by the tests but CMT test alters span argument. Due to the order of tests (CMT test runs last), mutating the span argument in CMT test does not trigger any real problems currently. Mark benchmark_cmd strings as const and setup the benchmark command using pointers. Because the benchmark command becomes const, the input arguments can be used directly. Besides being simpler, using the input arguments directly also removes the internal size restriction. CMT test has to create a copy of the benchmark command before altering the benchmark command. Signed-off-by: Ilpo Järvinen Tested-by: Shaopeng Tan Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Reviewed-by: "Wieczor-Retman, Maciej" Signed-off-by: Shuah Khan

selftests/resctrl: Don't use variable argument list for ->setup()

2023-07-25T14:53:53Z

struct resctrl_val_param has ->setup() function that accepts variable argument list. All test cases use only 1 argument as input and it's the struct resctrl_val_param pointer. Instead of variable argument list, directly pass struct resctrl_val_param pointer as the only parameter to ->setup(). 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: 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: Commonize the signal handler register/unregister for all tests

2023-04-13T17:34:23Z

After creating a child process with fork() in CAT test, if a signal such as SIGINT is received, the parent process will be terminated immediately, and therefore the child process will not be killed and also resctrlfs is not unmounted. There is a signal handler registered in CMT/MBM/MBA tests, which kills child process, unmount resctrlfs, cleanups result files, etc., if a signal such as SIGINT is received. Commonize the signal handler registered for CMT/MBM/MBA tests and reuse it in CAT. To reuse the signal handler to kill child process use global bm_pid instead of local bm_pid. Also, since the MBA/MBA/CMT/CAT are run in order, unregister the signal handler at the end of each test so that the signal handler cannot be inherited by other tests. Reviewed-by: Ilpo Jarvinen Reviewed-by: Reinette Chatre Signed-off-by: Shaopeng Tan Signed-off-by: Shuah Khan

selftests/resctrl: Flush stdout file buffer before executing fork()

2023-04-13T17:34:12Z

When a process has buffered output, a child process created by fork() will also copy buffered output. When using kselftest framework, the output (resctrl test result message) will be printed multiple times. Add fflush() to flush out the buffered output before executing fork(). Reviewed-by: Shuah Khan Reviewed-by: Reinette Chatre Signed-off-by: Shaopeng Tan Signed-off-by: Shuah Khan

selftests/resctrl: Allow ->setup() to return errors

2023-04-10T18:20:41Z

resctrl_val() assumes ->setup() always returns either 0 to continue tests or < 0 in case of the normal termination of tests after x runs. The latter overlaps with normal error returns. Define END_OF_TESTS (=1) to differentiate the normal termination of tests and return errors as negative values. Alter callers of ->setup() to handle errors properly. Fixes: 790bf585b0ee ("selftests/resctrl: Add Cache Allocation Technology (CAT) selftest") Fixes: ecdbb911f22d ("selftests/resctrl: Add MBM test") Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan

selftests/resctrl: Move ->setup() call outside of test specific branches

2023-04-10T18:20:35Z

resctrl_val() function is called only by MBM, MBA, and CMT tests which means the else branch is never used. Both test branches call param->setup(). Remove the unused else branch and place the ->setup() call outside of the test specific branches reducing code duplication. Co-developed-by: Fenghua Yu Signed-off-by: Fenghua Yu Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan