selftests/resctrl: Express span internally in bytes

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 <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan (Fujitsu) <tan.shaopeng@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/resctrl/mbm_test.c

@@ -40,7 +40,7 @@ show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, size_t span)
 	ksft_print_msg("%s Check MBM diff within %d%%\n",
 		       ret ? "Fail:" : "Pass:", MAX_DIFF_PERCENT);
 	ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);
-	ksft_print_msg("Span (MB): %zu\n", span);
+	ksft_print_msg("Span (MB): %zu\n", span / MB);
 	ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
 	ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
 

tools/testing/selftests/resctrl/resctrl_tests.c

@@ -185,8 +185,8 @@ int main(int argc, char **argv)
 	char benchmark_cmd_area[BENCHMARK_ARGS][BENCHMARK_ARG_SIZE];
 	int c, cpu_no = 1, argc_new = argc, i, no_of_bits = 0;
 	int ben_ind, ben_count, tests = 0;
+	size_t span = 250 * MB;
 	bool cat_test = true;
-	size_t span = 250;
 
 	for (i = 0; i < argc; i++) {
 		if (strcmp(argv[i], "-b") == 0) {

tools/testing/selftests/resctrl/resctrlfs.c

@@ -303,9 +303,9 @@ int taskset_benchmark(pid_t bm_pid, int cpu_no)
 void run_benchmark(int signum, siginfo_t *info, void *ucontext)
 {
 	int operation, ret, malloc_and_init_memory, memflush;
-	size_t span, buffer_span;
 	char **benchmark_cmd;
 	char resctrl_val[64];
+	size_t span;
 	FILE *fp;
 
 	benchmark_cmd = info->si_ptr;
@@ -326,12 +326,7 @@ void run_benchmark(int signum, siginfo_t *info, void *ucontext)
 		operation = atoi(benchmark_cmd[4]);
 		sprintf(resctrl_val, "%s", benchmark_cmd[5]);
 
-		if (strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
-			buffer_span = span * MB;
-		else
-			buffer_span = span;
-
-		if (run_fill_buf(buffer_span, malloc_and_init_memory, memflush,
+		if (run_fill_buf(span, malloc_and_init_memory, memflush,
 				 operation, resctrl_val))
 			fprintf(stderr, "Error in running fill buffer\n");
 	} else {