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 ilpo.jarvinen@linux.intel.com Tested-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Reviewed-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Cc: stable@vger.kernel.org --- 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..4eab2fad97fb 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 void run_mbm_test(const char * const *benchmark_cmd, int cpu_no) +static int test_prepare() { int res;

- ksft_print_msg("Starting MBM BW change ...\n"); + res = signal_handler_register(); + if (res) { + ksft_print_msg("Failed to register signal handler\n"); + return res; + }

res = mount_resctrlfs(); if (res) { - ksft_exit_fail_msg("Failed to mount resctrl FS\n"); + signal_handler_unregister(); + ksft_print_msg("Failed to mount resctrl FS\n"); + return res; + } + return 0; +} + +static void test_cleanup() +{ + 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"); + + 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 1e8b90077218..c37ffaa49844 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);

The test runner run_cmt_test() in resctrl_tests.c checks for CMT feature and does not run cmt_resctrl_val() if CMT is not supported. Then cmt_resctrl_val() also check is CMT is supported.

Remove the duplicated feature check for CMT from cmt_resctrl_val().

Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Tested-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com Reviewed-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Cc: stable@vger.kernel.org --- tools/testing/selftests/resctrl/cmt_test.c | 3 --- 1 file changed, 3 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c index cf2f5e92dea6..50bdbce9fba9 100644 --- a/tools/testing/selftests/resctrl/cmt_test.c +++ b/tools/testing/selftests/resctrl/cmt_test.c @@ -80,9 +80,6 @@ int cmt_resctrl_val(int cpu_no, int n, const char * const *benchmark_cmd) size_t span; int ret, i;

- if (!validate_resctrl_feature_request(CMT_STR)) - return -1; - ret = get_cbm_mask("L3", cbm_mask); if (ret) return ret;

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 ilpo.jarvinen@linux.intel.com Tested-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com Reviewed-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Cc: stable@vger.kernel.org # selftests/resctrl: Remove duplicate feature check from CMT test Cc: stable@vger.kernel.org # selftests/resctrl: Move _GNU_SOURCE define into Makefile --- tools/testing/selftests/resctrl/resctrl.h | 6 +- .../testing/selftests/resctrl/resctrl_tests.c | 10 +-- tools/testing/selftests/resctrl/resctrlfs.c | 69 ++++++++----------- 3 files changed, 34 insertions(+), 51 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h index d9b5df95849d..8578a8b4e145 100644 --- a/tools/testing/selftests/resctrl/resctrl.h +++ b/tools/testing/selftests/resctrl/resctrl.h @@ -27,10 +27,6 @@ #define RESCTRL_PATH "/sys/fs/resctrl" #define PHYS_ID_PATH "/sys/devices/system/cpu/cpu" #define INFO_PATH "/sys/fs/resctrl/info" -#define L3_PATH "/sys/fs/resctrl/info/L3" -#define MB_PATH "/sys/fs/resctrl/info/MB" -#define L3_MON_PATH "/sys/fs/resctrl/info/L3_MON" -#define L3_MON_FEATURES_PATH "/sys/fs/resctrl/info/L3_MON/mon_features"

#define ARCH_INTEL 1 #define ARCH_AMD 2 @@ -87,7 +83,7 @@ int get_resource_id(int cpu_no, int *resource_id); int mount_resctrlfs(void); int umount_resctrlfs(void); int validate_bw_report_request(char *bw_report); -bool validate_resctrl_feature_request(const char *resctrl_val); +bool validate_resctrl_feature_request(const char *resource, const char *feature); char *fgrep(FILE *inf, const char *str); int taskset_benchmark(pid_t bm_pid, int cpu_no); void run_benchmark(int signum, siginfo_t *info, void *ucontext); diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c index 4eab2fad97fb..7836bf0655fe 100644 --- a/tools/testing/selftests/resctrl/resctrl_tests.c +++ b/tools/testing/selftests/resctrl/resctrl_tests.c @@ -103,7 +103,9 @@ static void run_mbm_test(const char * const *benchmark_cmd, int cpu_no) return; }

- if (!validate_resctrl_feature_request(MBM_STR) || (get_vendor() != ARCH_INTEL)) { + if (!validate_resctrl_feature_request("L3_MON", "mbm_total_bytes") || + !validate_resctrl_feature_request("L3_MON", "mbm_local_bytes") || + (get_vendor() != ARCH_INTEL)) { ksft_test_result_skip("Hardware does not support MBM or MBM is disabled\n"); goto cleanup; } @@ -128,7 +130,7 @@ static void run_mba_test(const char * const *benchmark_cmd, int cpu_no) return; }

- if (!validate_resctrl_feature_request(MBA_STR) || (get_vendor() != ARCH_INTEL)) { + if (!validate_resctrl_feature_request("MB", NULL) || (get_vendor() != ARCH_INTEL)) { ksft_test_result_skip("Hardware does not support MBA or MBA is disabled\n"); goto cleanup; } @@ -151,7 +153,7 @@ static void run_cmt_test(const char * const *benchmark_cmd, int cpu_no) return; }

- if (!validate_resctrl_feature_request(CMT_STR)) { + if (!validate_resctrl_feature_request("L3_MON", "llc_occupancy")) { ksft_test_result_skip("Hardware does not support CMT or CMT is disabled\n"); goto cleanup; } @@ -176,7 +178,7 @@ static void run_cat_test(int cpu_no, int no_of_bits) return; }

- if (!validate_resctrl_feature_request(CAT_STR)) { + if (!validate_resctrl_feature_request("L3", NULL)) { ksft_test_result_skip("Hardware does not support CAT or CAT is disabled\n"); goto cleanup; } diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index bd36ee206602..3a8111362d26 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -8,6 +8,8 @@ * Sai Praneeth Prakhya sai.praneeth.prakhya@intel.com, * Fenghua Yu fenghua.yu@intel.com */ +#include <limits.h> + #include "resctrl.h"

static int find_resctrl_mount(char *buffer) @@ -604,63 +606,46 @@ char *fgrep(FILE *inf, const char *str)

/* * validate_resctrl_feature_request - Check if requested feature is valid. - * @resctrl_val: Requested feature + * @resource: Required resource (e.g., MB, L3, L2, L3_MON, etc.) + * @feature: Required monitor feature (in mon_features file). Can only be + * set for L3_MON. Must be NULL for all other resources. * - * Return: True if the feature is supported, else false. False is also - * returned if resctrl FS is not mounted. + * Return: True if the resource/feature is supported, else false. False is + * also returned if resctrl FS is not mounted. */ -bool validate_resctrl_feature_request(const char *resctrl_val) +bool validate_resctrl_feature_request(const char *resource, const char *feature) { + char res_path[PATH_MAX]; struct stat statbuf; - bool found = false; char *res; FILE *inf; int ret;

- if (!resctrl_val) + if (!resource) return false;

ret = find_resctrl_mount(NULL); if (ret) return false;

- if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR))) { - if (!stat(L3_PATH, &statbuf)) - return true; - } else if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) { - if (!stat(MB_PATH, &statbuf)) - return true; - } else if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) || - !strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) { - if (!stat(L3_MON_PATH, &statbuf)) { - inf = fopen(L3_MON_FEATURES_PATH, "r"); - if (!inf) - return false; - - if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) { - res = fgrep(inf, "llc_occupancy"); - if (res) { - found = true; - free(res); - } - } - - if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) { - res = fgrep(inf, "mbm_total_bytes"); - if (res) { - free(res); - res = fgrep(inf, "mbm_local_bytes"); - if (res) { - found = true; - free(res); - } - } - } - fclose(inf); - } - } + snprintf(res_path, sizeof(res_path), "%s/%s", INFO_PATH, resource); + + if (stat(res_path, &statbuf)) + return false; + + if (!feature) + return true; + + snprintf(res_path, sizeof(res_path), "%s/%s/mon_features", INFO_PATH, resource); + inf = fopen(res_path, "r"); + if (!inf) + return false; + + res = fgrep(inf, feature); + free(res); + fclose(inf);

- return found; + return !!res; }

int filter_dmesg(void)

The initial value of 5% chosen for the maximum allowed percentage difference between resctrl mbm value and IMC mbm value in commit 06bd03a57f8c ("selftests/resctrl: Fix MBA/MBM results reporting format") was "randomly chosen value" (as admitted by the changelog).

When running tests in our lab across a large number platforms, 5% difference upper bound for success seems a bit on the low side for the MBA and MBM tests. Some platforms produce outliers that are slightly above that, typically 6-7%, which leads MBA/MBM test frequently failing.

Replace the "randomly chosen value" with a success bound that is based on those measurements across large number of platforms by relaxing the MBA/MBM success bound to 8%. The relaxed bound removes the failures due the frequent outliers.

Fixes: 06bd03a57f8c ("selftests/resctrl: Fix MBA/MBM results reporting format") Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Tested-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com Reviewed-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Cc: stable@vger.kernel.org --- tools/testing/selftests/resctrl/mba_test.c | 2 +- tools/testing/selftests/resctrl/mbm_test.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c index cf8284dadcb2..d3bf4368341e 100644 --- a/tools/testing/selftests/resctrl/mba_test.c +++ b/tools/testing/selftests/resctrl/mba_test.c @@ -12,7 +12,7 @@

#define RESULT_FILE_NAME "result_mba" #define NUM_OF_RUNS 5 -#define MAX_DIFF_PERCENT 5 +#define MAX_DIFF_PERCENT 8 #define ALLOCATION_MAX 100 #define ALLOCATION_MIN 10 #define ALLOCATION_STEP 10 diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c index 1ae131a2e246..d3c0d30c676a 100644 --- a/tools/testing/selftests/resctrl/mbm_test.c +++ b/tools/testing/selftests/resctrl/mbm_test.c @@ -11,7 +11,7 @@ #include "resctrl.h"

#define RESULT_FILE_NAME "result_mbm" -#define MAX_DIFF_PERCENT 5 +#define MAX_DIFF_PERCENT 8 #define NUM_OF_RUNS 5

static int