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
17 static void
show_bw_info(unsigned long * bw_imc,unsigned long * bw_resc,int span)18 show_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
check_results(int span)47 static 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
mbm_setup(int num,...)86 static 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
mbm_test_cleanup(void)109 void mbm_test_cleanup(void)
110 {
111 remove(RESULT_FILE_NAME);
112 }
113
mbm_bw_change(int span,int cpu_no,char * bw_report,char ** benchmark_cmd)114 int 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_STR,
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, ¶m);
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 }
146