1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Memory Bandwidth Monitoring (MBM) test
  4 *
  5 * Copyright (C) 2018 Intel Corporation
  6 *
  7 * Authors:
  8 *    Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
  9 *    Fenghua Yu <fenghua.yu@intel.com>
 10 */
 11#include "resctrl.h"
 12
 13#define RESULT_FILE_NAME	"result_mbm"
 14#define MAX_DIFF		300
 15#define NUM_OF_RUNS		5
 16
 17static void
 18show_bw_info(unsigned long *bw_imc, unsigned long *bw_resc, int span)
 19{
 20	unsigned long avg_bw_imc = 0, avg_bw_resc = 0;
 21	unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
 22	long avg_diff = 0;
 23	int runs;
 24
 25	/*
 26	 * Discard the first value which is inaccurate due to monitoring setup
 27	 * transition phase.
 28	 */
 29	for (runs = 1; runs < NUM_OF_RUNS ; runs++) {
 30		sum_bw_imc += bw_imc[runs];
 31		sum_bw_resc += bw_resc[runs];
 32	}
 33
 34	avg_bw_imc = sum_bw_imc / 4;
 35	avg_bw_resc = sum_bw_resc / 4;
 36	avg_diff = avg_bw_resc - avg_bw_imc;
 37
 38	printf("%sok MBM: diff within %d%%\n",
 39	       labs(avg_diff) > MAX_DIFF ? "not " : "", MAX_DIFF);
 40	tests_run++;
 41	printf("# avg_diff: %lu\n", labs(avg_diff));
 42	printf("# Span (MB): %d\n", span);
 43	printf("# avg_bw_imc: %lu\n", avg_bw_imc);
 44	printf("# avg_bw_resc: %lu\n", avg_bw_resc);
 45}
 46
 47static int check_results(int span)
 48{
 49	unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS];
 50	char temp[1024], *token_array[8];
 51	char output[] = RESULT_FILE_NAME;
 52	int runs;
 53	FILE *fp;
 54
 55	printf("# Checking for pass/fail\n");
 56
 57	fp = fopen(output, "r");
 58	if (!fp) {
 59		perror(output);
 60
 61		return errno;
 62	}
 63
 64	runs = 0;
 65	while (fgets(temp, sizeof(temp), fp)) {
 66		char *token = strtok(temp, ":\t");
 67		int i = 0;
 68
 69		while (token) {
 70			token_array[i++] = token;
 71			token = strtok(NULL, ":\t");
 72		}
 73
 74		bw_resc[runs] = strtoul(token_array[5], NULL, 0);
 75		bw_imc[runs] = strtoul(token_array[3], NULL, 0);
 76		runs++;
 77	}
 78
 79	show_bw_info(bw_imc, bw_resc, span);
 80
 81	fclose(fp);
 82
 83	return 0;
 84}
 85
 86static int mbm_setup(int num, ...)
 87{
 88	struct resctrl_val_param *p;
 89	static int num_of_runs;
 90	va_list param;
 91	int ret = 0;
 92
 93	/* Run NUM_OF_RUNS times */
 94	if (num_of_runs++ >= NUM_OF_RUNS)
 95		return -1;
 96
 97	va_start(param, num);
 98	p = va_arg(param, struct resctrl_val_param *);
 99	va_end(param);
100
101	/* Set up shemata with 100% allocation on the first run. */
102	if (num_of_runs == 0)
103		ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
104				     p->resctrl_val);
105
106	return ret;
107}
108
109void mbm_test_cleanup(void)
110{
111	remove(RESULT_FILE_NAME);
112}
113
114int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
115{
116	struct resctrl_val_param param = {
117		.resctrl_val	= "mbm",
118		.ctrlgrp	= "c1",
119		.mongrp		= "m1",
120		.span		= span,
121		.cpu_no		= cpu_no,
122		.mum_resctrlfs	= 1,
123		.filename	= RESULT_FILE_NAME,
124		.bw_report	=  bw_report,
125		.setup		= mbm_setup
126	};
127	int ret;
128
129	remove(RESULT_FILE_NAME);
130
131	if (!validate_resctrl_feature_request("mbm"))
132		return -1;
133
134	ret = resctrl_val(benchmark_cmd, &param);
135	if (ret)
136		return ret;
137
138	ret = check_results(span);
139	if (ret)
140		return ret;
141
142	mbm_test_cleanup();
143
144	return 0;
145}