1 files changed, 145 insertions, 0 deletions
diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
new file mode 100644
index 000000000..5dc1dce89
--- /dev/null
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Memory Bandwidth Monitoring (MBM) test
+ *
+ * Copyright (C) 2018 Intel Corporation
+ *
+ * Authors:
+ *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
+ *    Fenghua Yu <fenghua.yu@intel.com>
+ */
+#include "resctrl.h"
+
+#define RESULT_FILE_NAME	"result_mbm"
+#define MAX_DIFF_PERCENT	8
+#define NUM_OF_RUNS		5
+
+static int
+show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, int span)
+{
+	unsigned long avg_bw_imc = 0, avg_bw_resc = 0;
+	unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
+	int runs, ret, avg_diff_per;
+	float avg_diff = 0;
+
+	/*
+	 * Discard the first value which is inaccurate due to monitoring setup
+	 * transition phase.
+	 */
+	for (runs = 1; runs < NUM_OF_RUNS ; runs++) {
+		sum_bw_imc += bw_imc[runs];
+		sum_bw_resc += bw_resc[runs];
+	}
+
+	avg_bw_imc = sum_bw_imc / 4;
+	avg_bw_resc = sum_bw_resc / 4;
+	avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;
+	avg_diff_per = (int)(avg_diff * 100);
+
+	ret = avg_diff_per > MAX_DIFF_PERCENT;
+	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): %d\n", span);
+	ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
+	ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
+
+	return ret;
+}
+
+static int check_results(int span)
+{
+	unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS];
+	char temp[1024], *token_array[8];
+	char output[] = RESULT_FILE_NAME;
+	int runs, ret;
+	FILE *fp;
+
+	ksft_print_msg("Checking for pass/fail\n");
+
+	fp = fopen(output, "r");
+	if (!fp) {
+		perror(output);
+
+		return errno;
+	}
+
+	runs = 0;
+	while (fgets(temp, sizeof(temp), fp)) {
+		char *token = strtok(temp, ":\t");
+		int i = 0;
+
+		while (token) {
+			token_array[i++] = token;
+			token = strtok(NULL, ":\t");
+		}
+
+		bw_resc[runs] = strtoul(token_array[5], NULL, 0);
+		bw_imc[runs] = strtoul(token_array[3], NULL, 0);
+		runs++;
+	}
+
+	ret = show_bw_info(bw_imc, bw_resc, span);
+
+	fclose(fp);
+
+	return ret;
+}
+
+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 END_OF_TESTS;
+
+	va_start(param, num);
+	p = va_arg(param, struct resctrl_val_param *);
+	va_end(param);
+
+	/* Set up shemata with 100% allocation on the first run. */
+	if (num_of_runs == 0)
+		ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
+				     p->resctrl_val);
+
+	return ret;
+}
+
+void mbm_test_cleanup(void)
+{
+	remove(RESULT_FILE_NAME);
+}
+
+int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
+{
+	struct resctrl_val_param param = {
+		.resctrl_val	= MBM_STR,
+		.ctrlgrp	= "c1",
+		.mongrp		= "m1",
+		.span		= span,
+		.cpu_no		= cpu_no,
+		.mum_resctrlfs	= 1,
+		.filename	= RESULT_FILE_NAME,
+		.bw_report	=  bw_report,
+		.setup		= mbm_setup
+	};
+	int ret;
+
+	remove(RESULT_FILE_NAME);
+
+	ret = resctrl_val(benchmark_cmd, &param);
+	if (ret)
+		return ret;
+
+	ret = check_results(span);
+	if (ret)
+		return ret;
+
+	mbm_test_cleanup();
+
+	return 0;
+}