From 3aff5146445582454c35900f3c0c972987cdd595 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Date: Mon, 2 Oct 2023 12:48:08 +0300 Subject: [PATCH] selftests/resctrl: Extend signal handler coverage to unmount on receiving signal MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- tools/testing/selftests/resctrl/cat_test.c | 8 --- .../testing/selftests/resctrl/resctrl_tests.c | 69 ++++++++++++------- tools/testing/selftests/resctrl/resctrl_val.c | 22 +++--- 3 files changed, 55 insertions(+), 44 deletions(-) diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index 97b87285ab2a..224ba8544d8a 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -167,12 +167,6 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) strcpy(param.filename, RESULT_FILE_NAME1); param.num_of_runs = 0; param.cpu_no = sibling_cpu_no; - } else { - ret = signal_handler_register(); - if (ret) { - kill(bm_pid, SIGKILL); - goto out; - } } remove(param.filename); @@ -209,10 +203,8 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) } close(pipefd[0]); kill(bm_pid, SIGKILL); - signal_handler_unregister(); } -out: cat_test_cleanup(); return ret; diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c index 823672a20a43..495aeee5b734 100644 --- a/tools/testing/selftests/resctrl/resctrl_tests.c +++ b/tools/testing/selftests/resctrl/resctrl_tests.c @@ -67,21 +67,45 @@ void tests_cleanup(void) cat_test_cleanup(); } +static int test_prepare(void) +{ + int res; + + res = signal_handler_register(); + if (res) { + ksft_print_msg("Failed to register signal handler\n"); + return res; + } + + res = mount_resctrlfs(); + if (res) { + signal_handler_unregister(); + ksft_print_msg("Failed to mount resctrl FS\n"); + return res; + } + return 0; +} + +static void test_cleanup(void) +{ + umount_resctrlfs(); + signal_handler_unregister(); +} + static void run_mbm_test(const char * const *benchmark_cmd, int cpu_no) { int res; ksft_print_msg("Starting MBM BW change ...\n"); - res = mount_resctrlfs(); - if (res) { - ksft_exit_fail_msg("Failed to mount resctrl FS\n"); + if (test_prepare()) { + ksft_exit_fail_msg("Abnormal failure when preparing for the test\n"); return; } if (!validate_resctrl_feature_request(MBM_STR) || (get_vendor() != ARCH_INTEL)) { ksft_test_result_skip("Hardware does not support MBM or MBM is disabled\n"); - goto umount; + goto cleanup; } res = mbm_bw_change(cpu_no, benchmark_cmd); @@ -89,8 +113,8 @@ static void run_mbm_test(const char * const *benchmark_cmd, int cpu_no) if ((get_vendor() == ARCH_INTEL) && res) ksft_print_msg("Intel MBM may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n"); -umount: - umount_resctrlfs(); +cleanup: + test_cleanup(); } static void run_mba_test(const char * const *benchmark_cmd, int cpu_no) @@ -99,22 +123,21 @@ static void run_mba_test(const char * const *benchmark_cmd, int cpu_no) ksft_print_msg("Starting MBA Schemata change ...\n"); - res = mount_resctrlfs(); - if (res) { - ksft_exit_fail_msg("Failed to mount resctrl FS\n"); + if (test_prepare()) { + ksft_exit_fail_msg("Abnormal failure when preparing for the test\n"); return; } if (!validate_resctrl_feature_request(MBA_STR) || (get_vendor() != ARCH_INTEL)) { ksft_test_result_skip("Hardware does not support MBA or MBA is disabled\n"); - goto umount; + goto cleanup; } res = mba_schemata_change(cpu_no, benchmark_cmd); ksft_test_result(!res, "MBA: schemata change\n"); -umount: - umount_resctrlfs(); +cleanup: + test_cleanup(); } static void run_cmt_test(const char * const *benchmark_cmd, int cpu_no) @@ -123,15 +146,14 @@ static void run_cmt_test(const char * const *benchmark_cmd, int cpu_no) ksft_print_msg("Starting CMT test ...\n"); - res = mount_resctrlfs(); - if (res) { - ksft_exit_fail_msg("Failed to mount resctrl FS\n"); + if (test_prepare()) { + ksft_exit_fail_msg("Abnormal failure when preparing for the test\n"); return; } if (!validate_resctrl_feature_request(CMT_STR)) { ksft_test_result_skip("Hardware does not support CMT or CMT is disabled\n"); - goto umount; + goto cleanup; } res = cmt_resctrl_val(cpu_no, 5, benchmark_cmd); @@ -139,8 +161,8 @@ static void run_cmt_test(const char * const *benchmark_cmd, int cpu_no) if ((get_vendor() == ARCH_INTEL) && res) ksft_print_msg("Intel CMT may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n"); -umount: - umount_resctrlfs(); +cleanup: + test_cleanup(); } static void run_cat_test(int cpu_no, int no_of_bits) @@ -149,22 +171,21 @@ static void run_cat_test(int cpu_no, int no_of_bits) ksft_print_msg("Starting CAT test ...\n"); - res = mount_resctrlfs(); - if (res) { - ksft_exit_fail_msg("Failed to mount resctrl FS\n"); + if (test_prepare()) { + ksft_exit_fail_msg("Abnormal failure when preparing for the test\n"); return; } if (!validate_resctrl_feature_request(CAT_STR)) { ksft_test_result_skip("Hardware does not support CAT or CAT is disabled\n"); - goto umount; + goto cleanup; } res = cat_perf_miss_val(cpu_no, no_of_bits, "L3"); ksft_test_result(!res, "CAT: test\n"); -umount: - umount_resctrlfs(); +cleanup: + test_cleanup(); } int main(int argc, char **argv) diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c index 01bbe11a8983..b8ca6fa40b3b 100644 --- a/tools/testing/selftests/resctrl/resctrl_val.c +++ b/tools/testing/selftests/resctrl/resctrl_val.c @@ -468,7 +468,9 @@ pid_t bm_pid, ppid; void ctrlc_handler(int signum, siginfo_t *info, void *ptr) { - kill(bm_pid, SIGKILL); + /* Only kill child after bm_pid is set after fork() */ + if (bm_pid) + kill(bm_pid, SIGKILL); umount_resctrlfs(); tests_cleanup(); ksft_print_msg("Ending\n\n"); @@ -485,6 +487,8 @@ int signal_handler_register(void) struct sigaction sigact = {}; int ret = 0; + bm_pid = 0; + sigact.sa_sigaction = ctrlc_handler; sigemptyset(&sigact.sa_mask); sigact.sa_flags = SA_SIGINFO; @@ -706,10 +710,6 @@ int resctrl_val(const char * const *benchmark_cmd, struct resctrl_val_param *par ksft_print_msg("Benchmark PID: %d\n", bm_pid); - ret = signal_handler_register(); - if (ret) - goto out; - /* * The cast removes constness but nothing mutates benchmark_cmd within * the context of this process. At the receiving process, it becomes @@ -721,19 +721,19 @@ int resctrl_val(const char * const *benchmark_cmd, struct resctrl_val_param *par /* Taskset benchmark to specified cpu */ ret = taskset_benchmark(bm_pid, param->cpu_no); if (ret) - goto unregister; + goto out; /* Write benchmark to specified control&monitoring grp in resctrl FS */ ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp, resctrl_val); if (ret) - goto unregister; + goto out; if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) || !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) { ret = initialize_mem_bw_imc(); if (ret) - goto unregister; + goto out; initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp, param->cpu_no, resctrl_val); @@ -748,7 +748,7 @@ int resctrl_val(const char * const *benchmark_cmd, struct resctrl_val_param *par sizeof(pipe_message)) { perror("# failed reading message from child process"); close(pipefd[0]); - goto unregister; + goto out; } } close(pipefd[0]); @@ -757,7 +757,7 @@ int resctrl_val(const char * const *benchmark_cmd, struct resctrl_val_param *par if (sigqueue(bm_pid, SIGUSR1, value) == -1) { perror("# sigqueue SIGUSR1 to child"); ret = errno; - goto unregister; + goto out; } /* Give benchmark enough time to fully run */ @@ -786,8 +786,6 @@ int resctrl_val(const char * const *benchmark_cmd, struct resctrl_val_param *par } } -unregister: - signal_handler_unregister(); out: kill(bm_pid, SIGKILL);