diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c
index 63b551c44f1d..8ae9ac150fd3 100644
--- a/tools/testing/selftests/resctrl/cache.c
+++ b/tools/testing/selftests/resctrl/cache.c
@@ -247,8 +247,7 @@ int cat_val(struct resctrl_val_param *param)
 			if (ret)
 				break;
 
-			if (run_fill_buf(param->span, memflush, operation,
-					 resctrl_val)) {
+			if (run_fill_buf(param->span, memflush, operation, true)) {
 				fprintf(stderr, "Error-running fill buffer\n");
 				ret = -1;
 				goto pe_close;
diff --git a/tools/testing/selftests/resctrl/fill_buf.c b/tools/testing/selftests/resctrl/fill_buf.c
index 5f16c4f5dfbf..0d425f26583a 100644
--- a/tools/testing/selftests/resctrl/fill_buf.c
+++ b/tools/testing/selftests/resctrl/fill_buf.c
@@ -101,15 +101,14 @@ static void fill_one_span_write(unsigned char *buf, size_t buf_size)
 	}
 }
 
-static int fill_cache_read(unsigned char *buf, size_t buf_size,
-			   char *resctrl_val)
+static int fill_cache_read(unsigned char *buf, size_t buf_size, bool once)
 {
 	int ret = 0;
 	FILE *fp;
 
 	while (1) {
 		ret = fill_one_span_read(buf, buf_size);
-		if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)))
+		if (once)
 			break;
 	}
 
@@ -125,19 +124,18 @@ static int fill_cache_read(unsigned char *buf, size_t buf_size,
 	return 0;
 }
 
-static int fill_cache_write(unsigned char *buf, size_t buf_size,
-			    char *resctrl_val)
+static int fill_cache_write(unsigned char *buf, size_t buf_size, bool once)
 {
 	while (1) {
 		fill_one_span_write(buf, buf_size);
-		if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)))
+		if (once)
 			break;
 	}
 
 	return 0;
 }
 
-static int fill_cache(size_t buf_size, int memflush, int op, char *resctrl_val)
+static int fill_cache(size_t buf_size, int memflush, int op, bool once)
 {
 	unsigned char *buf;
 	int ret;
@@ -151,9 +149,9 @@ static int fill_cache(size_t buf_size, int memflush, int op, char *resctrl_val)
 		mem_flush(buf, buf_size);
 
 	if (op == 0)
-		ret = fill_cache_read(buf, buf_size, resctrl_val);
+		ret = fill_cache_read(buf, buf_size, once);
 	else
-		ret = fill_cache_write(buf, buf_size, resctrl_val);
+		ret = fill_cache_write(buf, buf_size, once);
 
 	free(buf);
 
@@ -166,12 +164,12 @@ static int fill_cache(size_t buf_size, int memflush, int op, char *resctrl_val)
 	return 0;
 }
 
-int run_fill_buf(size_t span, int memflush, int op, char *resctrl_val)
+int run_fill_buf(size_t span, int memflush, int op, bool once)
 {
 	size_t cache_size = span;
 	int ret;
 
-	ret = fill_cache(cache_size, memflush, op, resctrl_val);
+	ret = fill_cache(cache_size, memflush, op, once);
 	if (ret) {
 		printf("\n Error in fill cache\n");
 		return -1;
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 3054cc4ef0e3..645ad407bd8d 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -97,7 +97,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
 			    char *resctrl_val);
 int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
 		    int group_fd, unsigned long flags);
-int run_fill_buf(size_t span, int memflush, int op, char *resctrl_val);
+int run_fill_buf(size_t span, int memflush, int op, bool once);
 int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param);
 int mbm_bw_change(size_t span, int cpu_no, char *bw_report, char **benchmark_cmd);
 void tests_cleanup(void);
diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
index 125ed0ca11e3..d511daeb6851 100644
--- a/tools/testing/selftests/resctrl/resctrl_tests.c
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -70,7 +70,7 @@ void tests_cleanup(void)
 	cat_test_cleanup();
 }
 
-static void run_mbm_test(bool has_ben, char **benchmark_cmd, size_t span,
+static void run_mbm_test(char **benchmark_cmd, size_t span,
 			 int cpu_no, char *bw_report)
 {
 	int res;
@@ -88,8 +88,6 @@ static void run_mbm_test(bool has_ben, char **benchmark_cmd, size_t span,
 		goto umount;
 	}
 
-	if (!has_ben)
-		sprintf(benchmark_cmd[4], "%s", MBA_STR);
 	res = mbm_bw_change(span, cpu_no, bw_report, benchmark_cmd);
 	ksft_test_result(!res, "MBM: bw change\n");
 	if ((get_vendor() == ARCH_INTEL) && res)
@@ -123,7 +121,7 @@ static void run_mba_test(char **benchmark_cmd, int cpu_no, char *bw_report)
 	umount_resctrlfs();
 }
 
-static void run_cmt_test(bool has_ben, char **benchmark_cmd, int cpu_no)
+static void run_cmt_test(char **benchmark_cmd, int cpu_no)
 {
 	int res;
 
@@ -140,8 +138,6 @@ static void run_cmt_test(bool has_ben, char **benchmark_cmd, int cpu_no)
 		goto umount;
 	}
 
-	if (!has_ben)
-		sprintf(benchmark_cmd[4], "%s", CMT_STR);
 	res = cmt_resctrl_val(cpu_no, 5, benchmark_cmd);
 	ksft_test_result(!res, "CMT: test\n");
 	if ((get_vendor() == ARCH_INTEL) && res)
@@ -274,7 +270,7 @@ int main(int argc, char **argv)
 		sprintf(benchmark_cmd[1], "%zu", span);
 		strcpy(benchmark_cmd[2], "1");
 		strcpy(benchmark_cmd[3], "0");
-		strcpy(benchmark_cmd[4], "");
+		strcpy(benchmark_cmd[4], "false");
 		benchmark_cmd[5] = NULL;
 	}
 
@@ -292,13 +288,13 @@ int main(int argc, char **argv)
 	ksft_set_plan(tests ? : 4);
 
 	if (mbm_test)
-		run_mbm_test(has_ben, benchmark_cmd, span, cpu_no, bw_report);
+		run_mbm_test(benchmark_cmd, span, cpu_no, bw_report);
 
 	if (mba_test)
 		run_mba_test(benchmark_cmd, cpu_no, bw_report);
 
 	if (cmt_test)
-		run_cmt_test(has_ben, benchmark_cmd, cpu_no);
+		run_cmt_test(benchmark_cmd, cpu_no);
 
 	if (cat_test)
 		run_cat_test(cpu_no, no_of_bits);
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 8a66445079f8..bd36ee206602 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -304,8 +304,8 @@ void run_benchmark(int signum, siginfo_t *info, void *ucontext)
 {
 	int operation, ret, memflush;
 	char **benchmark_cmd;
-	char resctrl_val[64];
 	size_t span;
+	bool once;
 	FILE *fp;
 
 	benchmark_cmd = info->si_ptr;
@@ -323,9 +323,14 @@ void run_benchmark(int signum, siginfo_t *info, void *ucontext)
 		span = strtoul(benchmark_cmd[1], NULL, 10);
 		memflush =  atoi(benchmark_cmd[2]);
 		operation = atoi(benchmark_cmd[3]);
-		sprintf(resctrl_val, "%s", benchmark_cmd[4]);
+		if (!strcmp(benchmark_cmd[4], "true"))
+			once = true;
+		else if (!strcmp(benchmark_cmd[4], "false"))
+			once = false;
+		else
+			PARENT_EXIT("Invalid once parameter");
 
-		if (run_fill_buf(span, memflush, operation, resctrl_val))
+		if (run_fill_buf(span, memflush, operation, once))
 			fprintf(stderr, "Error in running fill buffer\n");
 	} else {
 		/* Execute specified benchmark */
