selftests/resctrl: Clean up resctrl features check

Checking resctrl features call strcmp() to compare feature strings
(e.g. "mba", "cat" etc). The checkings are error prone and don't have
good coding style. Define the constant strings in macros and call
strncmp() to solve the potential issues.

Suggested-by: Shuah Khan <[e-mail]>
Tested-by: Babu Moger <[e-mail]>
Signed-off-by: Fenghua Yu <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/selftests/resctrl/cache.c

···
 	/*
 	 * Measure cache miss from perf.
 	 */
-	if (!strcmp(param->resctrl_val, "cat")) {
+	if (!strncmp(param->resctrl_val, CAT_STR, sizeof(CAT_STR))) {
 		ret = get_llc_perf(&llc_perf_miss);
 		if (ret < 0)
 			return ret;
···
 	/*
 	 * Measure llc occupancy from resctrl.
 	 */
-	if (!strcmp(param->resctrl_val, "cqm")) {
+	if (!strncmp(param->resctrl_val, CQM_STR, sizeof(CQM_STR))) {
 		ret = get_llc_occu_resctrl(&llc_occu_resc);
 		if (ret < 0)
 			return ret;
···
 	if (ret)
 		return ret;
 
-	if ((strcmp(resctrl_val, "cat") == 0)) {
+	if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR))) {
 		ret = initialize_llc_perf();
 		if (ret)
 			return ret;
···
 
 	/* Test runs until the callback setup() tells the test to stop. */
 	while (1) {
-		if (strcmp(resctrl_val, "cat") == 0) {
+		if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR))) {
 			ret = param->setup(1, param);
 			if (ret) {
 				ret = 0;

tools/testing/selftests/resctrl/cat_test.c

···
 		return -1;
 
 	struct resctrl_val_param param = {
-		.resctrl_val	= "cat",
+		.resctrl_val	= CAT_STR,
 		.cpu_no		= cpu_no,
 		.mum_resctrlfs	= 0,
 		.setup		= cat_setup,

tools/testing/selftests/resctrl/cqm_test.c

···
 	}
 
 	struct resctrl_val_param param = {
-		.resctrl_val	= "cqm",
+		.resctrl_val	= CQM_STR,
 		.ctrlgrp	= "c1",
 		.mongrp		= "m1",
 		.cpu_no		= cpu_no,

tools/testing/selftests/resctrl/fill_buf.c

···
 
 	while (1) {
 		ret = fill_one_span_read(start_ptr, end_ptr);
-		if (!strcmp(resctrl_val, "cat"))
+		if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)))
 			break;
 	}
 
···
 {
 	while (1) {
 		fill_one_span_write(start_ptr, end_ptr);
-		if (!strcmp(resctrl_val, "cat"))
+		if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)))
 			break;
 	}
 

tools/testing/selftests/resctrl/mba_test.c

···
 int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd)
 {
 	struct resctrl_val_param param = {
-		.resctrl_val	= "mba",
+		.resctrl_val	= MBA_STR,
 		.ctrlgrp	= "c1",
 		.mongrp		= "m1",
 		.cpu_no		= cpu_no,

tools/testing/selftests/resctrl/mbm_test.c

···
 int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
 {
 	struct resctrl_val_param param = {
-		.resctrl_val	= "mbm",
+		.resctrl_val	= MBM_STR,
 		.ctrlgrp	= "c1",
 		.mongrp		= "m1",
 		.span		= span,

tools/testing/selftests/resctrl/resctrl.h

···
 	int		(*setup)(int num, ...);
 };
 
+#define MBM_STR			"mbm"
+#define MBA_STR			"mba"
+#define CQM_STR			"cqm"
+#define CAT_STR			"cat"
+
 extern pid_t bm_pid, ppid;
 extern int tests_run;
 

tools/testing/selftests/resctrl/resctrl_tests.c

···
 			cqm_test = false;
 			cat_test = false;
 			while (token) {
-				if (!strcmp(token, "mbm")) {
+				if (!strncmp(token, MBM_STR, sizeof(MBM_STR))) {
 					mbm_test = true;
-				} else if (!strcmp(token, "mba")) {
+				} else if (!strncmp(token, MBA_STR, sizeof(MBA_STR))) {
 					mba_test = true;
-				} else if (!strcmp(token, "cqm")) {
+				} else if (!strncmp(token, CQM_STR, sizeof(CQM_STR))) {
 					cqm_test = true;
-				} else if (!strcmp(token, "cat")) {
+				} else if (!strncmp(token, CAT_STR, sizeof(CAT_STR))) {
 					cat_test = true;
 				} else {
 					printf("invalid argument\n");
···
 	if (!is_amd && mbm_test) {
 		printf("# Starting MBM BW change ...\n");
 		if (!has_ben)
-			sprintf(benchmark_cmd[5], "%s", "mba");
+			sprintf(benchmark_cmd[5], "%s", MBA_STR);
 		res = mbm_bw_change(span, cpu_no, bw_report, benchmark_cmd);
 		printf("%sok MBM: bw change\n", res ? "not " : "");
 		mbm_test_cleanup();
···
 	if (cqm_test) {
 		printf("# Starting CQM test ...\n");
 		if (!has_ben)
-			sprintf(benchmark_cmd[5], "%s", "cqm");
+			sprintf(benchmark_cmd[5], "%s", CQM_STR);
 		res = cqm_resctrl_val(cpu_no, no_of_bits, benchmark_cmd);
 		printf("%sok CQM: test\n", res ? "not " : "");
 		cqm_test_cleanup();

tools/testing/selftests/resctrl/resctrl_val.c

···
 		return;
 	}
 
-	if (strcmp(resctrl_val, "mbm") == 0)
+	if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
 		set_mbm_path(ctrlgrp, mongrp, resource_id);
 
-	if ((strcmp(resctrl_val, "mba") == 0)) {
+	if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
 		if (ctrlgrp)
 			sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH,
 				RESCTRL_PATH, ctrlgrp, resource_id);
···
 		return;
 	}
 
-	if (strcmp(resctrl_val, "cqm") == 0)
+	if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
 		set_cqm_path(ctrlgrp, mongrp, resource_id);
 }
 
···
 	if (strcmp(param->filename, "") == 0)
 		sprintf(param->filename, "stdio");
 
-	if ((strcmp(resctrl_val, "mba")) == 0 ||
-	    (strcmp(resctrl_val, "mbm")) == 0) {
+	if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
+	    !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
 		ret = validate_bw_report_request(param->bw_report);
 		if (ret)
 			return ret;
···
 	if (ret)
 		goto out;
 
-	if ((strcmp(resctrl_val, "mbm") == 0) ||
-	    (strcmp(resctrl_val, "mba") == 0)) {
+	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;
 
 		initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
 					  param->cpu_no, resctrl_val);
-	} else if (strcmp(resctrl_val, "cqm") == 0)
+	} else if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
 		initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
 					    param->cpu_no, resctrl_val);
 
···
 
 	/* Test runs until the callback setup() tells the test to stop. */
 	while (1) {
-		if ((strcmp(resctrl_val, "mbm") == 0) ||
-		    (strcmp(resctrl_val, "mba") == 0)) {
+		if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
+		    !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
 			ret = param->setup(1, param);
 			if (ret) {
 				ret = 0;
···
 			ret = measure_vals(param, &bw_resc_start);
 			if (ret)
 				break;
-		} else if (strcmp(resctrl_val, "cqm") == 0) {
+		} else if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR))) {
 			ret = param->setup(1, param);
 			if (ret) {
 				ret = 0;

tools/testing/selftests/resctrl/resctrlfs.c

···
 		operation = atoi(benchmark_cmd[4]);
 		sprintf(resctrl_val, "%s", benchmark_cmd[5]);
 
-		if (strcmp(resctrl_val, "cqm") != 0)
+		if (strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
 			buffer_span = span * MB;
 		else
 			buffer_span = span;
···
 		goto out;
 
 	/* Create mon grp and write pid into it for "mbm" and "cqm" test */
-	if ((strcmp(resctrl_val, "cqm") == 0) ||
-	    (strcmp(resctrl_val, "mbm") == 0)) {
+	if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)) ||
+	    !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
 		if (strlen(mongrp)) {
 			sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
 			sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
···
 	int resource_id, ret = 0;
 	FILE *fp;
 
-	if ((strcmp(resctrl_val, "mba") != 0) &&
-	    (strcmp(resctrl_val, "cat") != 0) &&
-	    (strcmp(resctrl_val, "cqm") != 0))
+	if (strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) &&
+	    strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) &&
+	    strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
 		return -ENOENT;
 
 	if (!schemata) {
···
 	else
 		sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);
 
-	if (!strcmp(resctrl_val, "cat") || !strcmp(resctrl_val, "cqm"))
+	if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) ||
+	    !strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
 		sprintf(schema, "%s%d%c%s", "L3:", resource_id, '=', schemata);
-	if (strcmp(resctrl_val, "mba") == 0)
+	if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)))
 		sprintf(schema, "%s%d%c%s", "MB:", resource_id, '=', schemata);
 
 	fp = fopen(controlgroup, "w");