There is a comment "Set up shemata with 100% allocation on the first run" in function mbm_setup(), but there is an increment bug and the condition "num_of_runs == 0" will never be met and write_schemata() will never be called to set schemata to 100%. Even if write_schemata() is called in MBM test, since it is not supported for MBM test it does not set the schemata. This is currently fine because resctrl_val_parm->mum_resctrlfs is always 1 and umount/mount will be run in each test to set the schemata to 100%.

To support the usage when MBM test does not unmount/remount resctrl filesystem before the test starts, fix to call write_schemata() and set schemata properly when the function is called for the first time.

Also, remove static local variable 'num_of_runs' because this is not needed as there is resctrl_val_param->num_of_runs which should be used instead like in cat_setup().

Reviewed-by: Reinette Chatre reinette.chatre@intel.com Signed-off-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com --- tools/testing/selftests/resctrl/mbm_test.c | 13 +++++++------ tools/testing/selftests/resctrl/resctrlfs.c | 4 +++- 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c index 8392e5c55ed0..6d550f012829 100644 --- a/tools/testing/selftests/resctrl/mbm_test.c +++ b/tools/testing/selftests/resctrl/mbm_test.c @@ -89,23 +89,24 @@ static int check_results(int span) static int mbm_setup(int num, ...) { struct resctrl_val_param *p; - static int num_of_runs; va_list param; int ret = 0;

- /* Run NUM_OF_RUNS times */ - if (num_of_runs++ >= NUM_OF_RUNS) - return -1; - va_start(param, num); p = va_arg(param, struct resctrl_val_param *); va_end(param);

+ /* Run NUM_OF_RUNS times */ + if (p->num_of_runs >= NUM_OF_RUNS) + return -1; + /* Set up shemata with 100% allocation on the first run. */ - if (num_of_runs == 0) + if (p->num_of_runs == 0) ret = write_schemata(p->ctrlgrp, "100", p->cpu_no, p->resctrl_val);

+ p->num_of_runs++; + return ret; }

diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index 6f543e470ad4..8546bc9f1786 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -498,6 +498,7 @@ int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, char *resctrl_val) FILE *fp;

if (strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) && + strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) && strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) && strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) return -ENOENT; @@ -523,7 +524,8 @@ int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, char *resctrl_val) if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) || !strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) sprintf(schema, "%s%d%c%s", "L3:", resource_id, '=', schemata); - if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) + if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) || + !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) sprintf(schema, "%s%d%c%s", "MB:", resource_id, '=', schemata);

fp = fopen(controlgroup, "w");

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 skhan@linuxfoundation.org Reviewed-by: Reinette Chatre reinette.chatre@intel.com Signed-off-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com --- tools/testing/selftests/resctrl/cat_test.c | 1 + tools/testing/selftests/resctrl/resctrl_val.c | 1 + tools/testing/selftests/resctrl/resctrlfs.c | 1 + 3 files changed, 3 insertions(+)

diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index 1c5e90c63254..6a8306b0a109 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -167,6 +167,7 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) return errno; }

+ fflush(stdout); bm_pid = fork();

/* Set param values for child thread which will be allocated bitmask diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c index b32b96356ec7..6948843bf995 100644 --- a/tools/testing/selftests/resctrl/resctrl_val.c +++ b/tools/testing/selftests/resctrl/resctrl_val.c @@ -629,6 +629,7 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param) * Fork to start benchmark, save child's pid so that it can be killed * when needed */ + fflush(stdout); bm_pid = fork(); if (bm_pid == -1) { perror("# Unable to fork"); diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index 8546bc9f1786..d95688298469 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -678,6 +678,7 @@ int filter_dmesg(void) perror("pipe"); return ret; } + fflush(stdout); pid = fork(); if (pid == 0) { close(pipefds[0]);

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 ilpo.jarvinen@linux.intel.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com Signed-off-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com --- tools/testing/selftests/resctrl/cat_test.c | 9 ++- tools/testing/selftests/resctrl/fill_buf.c | 14 ---- tools/testing/selftests/resctrl/resctrl.h | 2 + tools/testing/selftests/resctrl/resctrl_val.c | 66 ++++++++++++++----- 4 files changed, 58 insertions(+), 33 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index 477b62dac546..0bdf0305a506 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -103,7 +103,6 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) unsigned long l_mask, l_mask_1; int ret, pipefd[2], sibling_cpu_no; char pipe_message; - pid_t bm_pid;

cache_size = 0;

@@ -181,6 +180,12 @@ 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); @@ -217,8 +222,10 @@ 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(); if (bm_pid) umount_resctrlfs(); diff --git a/tools/testing/selftests/resctrl/fill_buf.c b/tools/testing/selftests/resctrl/fill_buf.c index 56ccbeae0638..322c6812e15c 100644 --- a/tools/testing/selftests/resctrl/fill_buf.c +++ b/tools/testing/selftests/resctrl/fill_buf.c @@ -33,14 +33,6 @@ static void sb(void) #endif }

-static void ctrl_handler(int signo) -{ - free(startptr); - printf("\nEnding\n"); - sb(); - exit(EXIT_SUCCESS); -} - static void cl_flush(void *p) { #if defined(__i386) || defined(__x86_64) @@ -198,12 +190,6 @@ int run_fill_buf(unsigned long span, int malloc_and_init_memory, unsigned long long cache_size = span; int ret;

- /* set up ctrl-c handler */ - if (signal(SIGINT, ctrl_handler) == SIG_ERR) - printf("Failed to catch SIGINT!\n"); - if (signal(SIGHUP, ctrl_handler) == SIG_ERR) - printf("Failed to catch SIGHUP!\n"); - ret = fill_cache(cache_size, malloc_and_init_memory, memflush, op, resctrl_val); if (ret) { diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h index f0ded31fb3c7..92b59d2f603d 100644 --- a/tools/testing/selftests/resctrl/resctrl.h +++ b/tools/testing/selftests/resctrl/resctrl.h @@ -107,6 +107,8 @@ void mba_test_cleanup(void); int get_cbm_mask(char *cache_type, char *cbm_mask); int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size); void ctrlc_handler(int signum, siginfo_t *info, void *ptr); +int signal_handler_register(void); +void signal_handler_unregister(void); int cat_val(struct resctrl_val_param *param); void cat_test_cleanup(void); int cat_perf_miss_val(int cpu_no, int no_of_bits, char *cache_type); diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c index 6948843bf995..7c8d5c25e6da 100644 --- a/tools/testing/selftests/resctrl/resctrl_val.c +++ b/tools/testing/selftests/resctrl/resctrl_val.c @@ -476,6 +476,45 @@ void ctrlc_handler(int signum, siginfo_t *info, void *ptr) exit(EXIT_SUCCESS); }

+/* + * Register CTRL-C handler for parent, as it has to kill + * child process before exiting. + */ +int signal_handler_register(void) +{ + struct sigaction sigact; + int ret = 0; + + sigact.sa_sigaction = ctrlc_handler; + sigemptyset(&sigact.sa_mask); + sigact.sa_flags = SA_SIGINFO; + if (sigaction(SIGINT, &sigact, NULL) || + sigaction(SIGTERM, &sigact, NULL) || + sigaction(SIGHUP, &sigact, NULL)) { + perror("# sigaction"); + ret = -1; + } + return ret; +} + +/* + * Reset signal handler to SIG_DFL. + * Non-Value return because the caller should keep + * the error code of other path even if sigaction fails. + */ +void signal_handler_unregister(void) +{ + struct sigaction sigact; + + sigact.sa_handler = SIG_DFL; + sigemptyset(&sigact.sa_mask); + if (sigaction(SIGINT, &sigact, NULL) || + sigaction(SIGTERM, &sigact, NULL) || + sigaction(SIGHUP, &sigact, NULL)) { + perror("# sigaction"); + } +} + /* * print_results_bw: the memory bandwidth results are stored in a file * @filename: file that stores the results @@ -671,39 +710,28 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param)

ksft_print_msg("Benchmark PID: %d\n", bm_pid);

- /* - * Register CTRL-C handler for parent, as it has to kill benchmark - * before exiting - */ - sigact.sa_sigaction = ctrlc_handler; - sigemptyset(&sigact.sa_mask); - sigact.sa_flags = SA_SIGINFO; - if (sigaction(SIGINT, &sigact, NULL) || - sigaction(SIGTERM, &sigact, NULL) || - sigaction(SIGHUP, &sigact, NULL)) { - perror("# sigaction"); - ret = errno; + ret = signal_handler_register(); + if (ret) goto out; - }

value.sival_ptr = benchmark_cmd;

/* Taskset benchmark to specified cpu */ ret = taskset_benchmark(bm_pid, param->cpu_no); if (ret) - goto out; + goto unregister;

/* 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 out; + goto unregister;

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 out; + goto unregister;

initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp, param->cpu_no, resctrl_val); @@ -718,7 +746,7 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param) sizeof(pipe_message)) { perror("# failed reading message from child process"); close(pipefd[0]); - goto out; + goto unregister; } } close(pipefd[0]); @@ -727,7 +755,7 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param) if (sigqueue(bm_pid, SIGUSR1, value) == -1) { perror("# sigqueue SIGUSR1 to child"); ret = errno; - goto out; + goto unregister; }

/* Give benchmark enough time to fully run */ @@ -761,6 +789,8 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param) } }

+unregister: + signal_handler_unregister(); out: kill(bm_pid, SIGKILL); umount_resctrlfs();