Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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_PERCENT 5
15#define NUM_OF_RUNS 5
16
17static int
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 int runs, ret, avg_diff_per;
23 float avg_diff = 0;
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 = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;
37 avg_diff_per = (int)(avg_diff * 100);
38
39 ret = avg_diff_per > MAX_DIFF_PERCENT;
40 ksft_print_msg("%s Check MBM diff within %d%%\n",
41 ret ? "Fail:" : "Pass:", MAX_DIFF_PERCENT);
42 ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);
43 ksft_print_msg("Span (MB): %d\n", span);
44 ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
45 ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
46
47 return ret;
48}
49
50static int check_results(int span)
51{
52 unsigned long bw_imc[NUM_OF_RUNS], bw_resc[NUM_OF_RUNS];
53 char temp[1024], *token_array[8];
54 char output[] = RESULT_FILE_NAME;
55 int runs, ret;
56 FILE *fp;
57
58 ksft_print_msg("Checking for pass/fail\n");
59
60 fp = fopen(output, "r");
61 if (!fp) {
62 perror(output);
63
64 return errno;
65 }
66
67 runs = 0;
68 while (fgets(temp, sizeof(temp), fp)) {
69 char *token = strtok(temp, ":\t");
70 int i = 0;
71
72 while (token) {
73 token_array[i++] = token;
74 token = strtok(NULL, ":\t");
75 }
76
77 bw_resc[runs] = strtoul(token_array[5], NULL, 0);
78 bw_imc[runs] = strtoul(token_array[3], NULL, 0);
79 runs++;
80 }
81
82 ret = show_bw_info(bw_imc, bw_resc, span);
83
84 fclose(fp);
85
86 return ret;
87}
88
89static int mbm_setup(int num, ...)
90{
91 struct resctrl_val_param *p;
92 va_list param;
93 int ret = 0;
94
95 va_start(param, num);
96 p = va_arg(param, struct resctrl_val_param *);
97 va_end(param);
98
99 /* Run NUM_OF_RUNS times */
100 if (p->num_of_runs >= NUM_OF_RUNS)
101 return END_OF_TESTS;
102
103 /* Set up shemata with 100% allocation on the first run. */
104 if (p->num_of_runs == 0)
105 ret = write_schemata(p->ctrlgrp, "100", p->cpu_no,
106 p->resctrl_val);
107
108 p->num_of_runs++;
109
110 return ret;
111}
112
113void mbm_test_cleanup(void)
114{
115 remove(RESULT_FILE_NAME);
116}
117
118int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd)
119{
120 struct resctrl_val_param param = {
121 .resctrl_val = MBM_STR,
122 .ctrlgrp = "c1",
123 .mongrp = "m1",
124 .span = span,
125 .cpu_no = cpu_no,
126 .mum_resctrlfs = true,
127 .filename = RESULT_FILE_NAME,
128 .bw_report = bw_report,
129 .setup = mbm_setup
130 };
131 int ret;
132
133 remove(RESULT_FILE_NAME);
134
135 ret = resctrl_val(benchmark_cmd, ¶m);
136 if (ret)
137 goto out;
138
139 ret = check_results(span);
140
141out:
142 mbm_test_cleanup();
143
144 return ret;
145}