selftests/resctrl: Add MBM test

MBM (Memory Bandwidth Monitoring) test is the first implemented selftest.
It starts a stressful memory bandwidth benchmark and assigns the
bandwidth pid in a resctrl monitoring group. Read and compare perf IMC
counter and MBM total bytes for the benchmark. The numbers should be
close enough to pass the test.

Default benchmark is built-in fill_buf. But users can specify their
own benchmark by option "-b".

We can add memory bandwidth monitoring for multiple processes in the
future.

Co-developed-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Co-developed-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

1 files changed, 132 insertions, 0 deletions

diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
new file mode 100644
index 000000000000..496c8030fe43
--- /dev/null
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Resctrl tests
+ *
+ * Copyright (C) 2018 Intel Corporation
+ *
+ * Authors:
+ *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
+ *    Fenghua Yu <fenghua.yu@intel.com>
+ */
+#include "resctrl.h"
+
+#define BENCHMARK_ARGS		64
+#define BENCHMARK_ARG_SIZE	64
+
+static void cmd_help(void)
+{
+	printf("usage: resctrl_tests [-h] [-b \"benchmark_cmd [options]\"] [-t test list]\n");
+	printf("\t-b benchmark_cmd [options]: run specified benchmark\n");
+	printf("\t default benchmark is builtin fill_buf\n");
+	printf("\t-t test list: run tests specified in the test list, ");
+	printf("e.g. -t mbm,mba\n");
+	printf("\t-h: help\n");
+}
+
+void tests_cleanup(void)
+{
+	mbm_test_cleanup();
+}
+
+int main(int argc, char **argv)
+{
+	int res, c, cpu_no = 1, span = 250, argc_new = argc, i, ben_ind;
+	char *benchmark_cmd[BENCHMARK_ARGS], bw_report[64], bm_type[64];
+	char benchmark_cmd_area[BENCHMARK_ARGS][BENCHMARK_ARG_SIZE];
+	bool has_ben = false, mbm_test = true;
+	int ben_count;
+
+	for (i = 0; i < argc; i++) {
+		if (strcmp(argv[i], "-b") == 0) {
+			ben_ind = i + 1;
+			ben_count = argc - ben_ind;
+			argc_new = ben_ind - 1;
+			has_ben = true;
+			break;
+		}
+	}
+
+	while ((c = getopt(argc_new, argv, "ht:b:")) != -1) {
+		char *token;
+
+		switch (c) {
+		case 't':
+			token = strtok(optarg, ",");
+
+			mbm_test = false;
+			while (token) {
+				if (!strcmp(token, "mbm")) {
+					mbm_test = true;
+				} else {
+					printf("invalid argument\n");
+
+					return -1;
+				}
+				token = strtok(NULL, ":\t");
+			}
+			break;
+		case 'p':
+			cpu_no = atoi(optarg);
+			break;
+		case 'h':
+			cmd_help();
+
+			return 0;
+		default:
+			printf("invalid argument\n");
+
+			return -1;
+		}
+	}
+
+	printf("TAP version 13\n");
+
+	/*
+	 * Typically we need root privileges, because:
+	 * 1. We write to resctrl FS
+	 * 2. We execute perf commands
+	 */
+	if (geteuid() != 0)
+		printf("# WARNING: not running as root, tests may fail.\n");
+
+	if (has_ben) {
+		/* Extract benchmark command from command line. */
+		for (i = ben_ind; i < argc; i++) {
+			benchmark_cmd[i - ben_ind] = benchmark_cmd_area[i];
+			sprintf(benchmark_cmd[i - ben_ind], "%s", argv[i]);
+		}
+		benchmark_cmd[ben_count] = NULL;
+	} else {
+		/* If no benchmark is given by "-b" argument, use fill_buf. */
+		for (i = 0; i < 6; i++)
+			benchmark_cmd[i] = benchmark_cmd_area[i];
+
+		strcpy(benchmark_cmd[0], "fill_buf");
+		sprintf(benchmark_cmd[1], "%d", span);
+		strcpy(benchmark_cmd[2], "1");
+		strcpy(benchmark_cmd[3], "1");
+		strcpy(benchmark_cmd[4], "0");
+		strcpy(benchmark_cmd[5], "");
+		benchmark_cmd[6] = NULL;
+	}
+
+	sprintf(bw_report, "reads");
+	sprintf(bm_type, "fill_buf");
+
+	check_resctrlfs_support();
+	filter_dmesg();
+
+	if (mbm_test) {
+		printf("# Starting MBM BW change ...\n");
+		if (!has_ben)
+			sprintf(benchmark_cmd[5], "%s", "mba");
+		res = mbm_bw_change(span, cpu_no, bw_report, benchmark_cmd);
+		printf("%sok MBM: bw change\n", res ? "not " : "");
+		mbm_test_cleanup();
+		tests_run++;
+	}
+
+	printf("1..%d\n", tests_run);
+
+	return 0;
+}