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225 lines · 5.6 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Memory Bandwidth Allocation (MBA) test
4 *
5 * Copyright (C) 2018 Intel Corporation
6 *
7 * Authors:
8 * Sai Praneeth Prakhya <[email protected]>,
9 * Fenghua Yu <[email protected]>
10 */
11#include "resctrl.h"
12
13#define RESULT_FILE_NAME "result_mba"
14#define NUM_OF_RUNS 5
15#define MAX_DIFF_PERCENT 15
16#define ALLOCATION_MAX 100
17#define ALLOCATION_MIN 10
18#define ALLOCATION_STEP 10
19
20static int mba_init(const struct resctrl_test *test,
21 const struct user_params *uparams,
22 const struct resctrl_val_param *param, int domain_id)
23{
24 int ret;
25
26 ret = initialize_read_mem_bw_imc();
27 if (ret)
28 return ret;
29
30 initialize_mem_bw_resctrl(param, domain_id);
31
32 return 0;
33}
34
35/*
36 * Change schemata percentage from 100 to 10%. Write schemata to specified
37 * con_mon grp, mon_grp in resctrl FS.
38 * For each allocation, run 5 times in order to get average values.
39 */
40static int mba_setup(const struct resctrl_test *test,
41 const struct user_params *uparams,
42 struct resctrl_val_param *p)
43{
44 static unsigned int allocation = ALLOCATION_MIN;
45 static int runs_per_allocation;
46 char allocation_str[64];
47 int ret;
48
49 if (runs_per_allocation >= NUM_OF_RUNS)
50 runs_per_allocation = 0;
51
52 /* Only set up schemata once every NUM_OF_RUNS of allocations */
53 if (runs_per_allocation++ != 0)
54 return 0;
55
56 if (allocation > ALLOCATION_MAX)
57 return END_OF_TESTS;
58
59 sprintf(allocation_str, "%d", allocation);
60
61 ret = write_schemata(p->ctrlgrp, allocation_str, uparams->cpu, test->resource);
62 if (ret < 0)
63 return ret;
64
65 allocation += ALLOCATION_STEP;
66
67 return 0;
68}
69
70static int mba_measure(const struct user_params *uparams,
71 struct resctrl_val_param *param, pid_t bm_pid)
72{
73 return measure_read_mem_bw(uparams, param, bm_pid);
74}
75
76static bool show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
77{
78 unsigned int allocation;
79 bool ret = false;
80 int runs;
81
82 ksft_print_msg("Results are displayed in (MB)\n");
83 /* Memory bandwidth from 100% down to 10% */
84 for (allocation = 0; allocation < ALLOCATION_MAX / ALLOCATION_STEP;
85 allocation++) {
86 unsigned long sum_bw_imc = 0, sum_bw_resc = 0;
87 long avg_bw_imc, avg_bw_resc;
88 int avg_diff_per;
89 float avg_diff;
90
91 for (runs = NUM_OF_RUNS * allocation;
92 runs < NUM_OF_RUNS * allocation + NUM_OF_RUNS ; runs++) {
93 sum_bw_imc += bw_imc[runs];
94 sum_bw_resc += bw_resc[runs];
95 }
96
97 avg_bw_imc = sum_bw_imc / NUM_OF_RUNS;
98 avg_bw_resc = sum_bw_resc / NUM_OF_RUNS;
99 if (avg_bw_imc < THROTTLE_THRESHOLD || avg_bw_resc < THROTTLE_THRESHOLD) {
100 ksft_print_msg("Bandwidth below threshold (%d MiB). Dropping results from MBA schemata %u.\n",
101 THROTTLE_THRESHOLD,
102 ALLOCATION_MIN + ALLOCATION_STEP * allocation);
103 continue;
104 }
105
106 avg_diff = (float)labs(avg_bw_resc - avg_bw_imc) / avg_bw_imc;
107 avg_diff_per = (int)(avg_diff * 100);
108
109 ksft_print_msg("%s Check MBA diff within %d%% for schemata %u\n",
110 avg_diff_per > MAX_DIFF_PERCENT ?
111 "Fail:" : "Pass:",
112 MAX_DIFF_PERCENT,
113 ALLOCATION_MIN + ALLOCATION_STEP * allocation);
114
115 ksft_print_msg("avg_diff_per: %d%%\n", avg_diff_per);
116 ksft_print_msg("avg_bw_imc: %lu\n", avg_bw_imc);
117 ksft_print_msg("avg_bw_resc: %lu\n", avg_bw_resc);
118 if (avg_diff_per > MAX_DIFF_PERCENT)
119 ret = true;
120 }
121
122 ksft_print_msg("%s Check schemata change using MBA\n",
123 ret ? "Fail:" : "Pass:");
124 if (ret)
125 ksft_print_msg("At least one test failed\n");
126
127 return ret;
128}
129
130static int check_results(void)
131{
132 unsigned long bw_resc[NUM_OF_RUNS * ALLOCATION_MAX / ALLOCATION_STEP];
133 unsigned long bw_imc[NUM_OF_RUNS * ALLOCATION_MAX / ALLOCATION_STEP];
134 char *token_array[8], output[] = RESULT_FILE_NAME, temp[512];
135 int runs;
136 FILE *fp;
137
138 fp = fopen(output, "r");
139 if (!fp) {
140 ksft_perror(output);
141
142 return -1;
143 }
144
145 runs = 0;
146 while (fgets(temp, sizeof(temp), fp)) {
147 char *token = strtok(temp, ":\t");
148 int fields = 0;
149
150 while (token) {
151 token_array[fields++] = token;
152 token = strtok(NULL, ":\t");
153 }
154
155 /* Field 3 is perf imc value */
156 bw_imc[runs] = strtoul(token_array[3], NULL, 0);
157 /* Field 5 is resctrl value */
158 bw_resc[runs] = strtoul(token_array[5], NULL, 0);
159 runs++;
160 }
161
162 fclose(fp);
163
164 return show_mba_info(bw_imc, bw_resc);
165}
166
167static void mba_test_cleanup(void)
168{
169 remove(RESULT_FILE_NAME);
170}
171
172static int mba_run_test(const struct resctrl_test *test, const struct user_params *uparams)
173{
174 struct resctrl_val_param param = {
175 .ctrlgrp = "c1",
176 .filename = RESULT_FILE_NAME,
177 .init = mba_init,
178 .setup = mba_setup,
179 .measure = mba_measure,
180 };
181 struct fill_buf_param fill_buf = {};
182 int ret;
183
184 remove(RESULT_FILE_NAME);
185
186 if (uparams->fill_buf) {
187 fill_buf.buf_size = uparams->fill_buf->buf_size;
188 fill_buf.memflush = uparams->fill_buf->memflush;
189 param.fill_buf = &fill_buf;
190 } else if (!uparams->benchmark_cmd[0]) {
191 ssize_t buf_size;
192
193 buf_size = get_fill_buf_size(uparams->cpu, "L3");
194 if (buf_size < 0)
195 return buf_size;
196 fill_buf.buf_size = buf_size;
197 fill_buf.memflush = true;
198 param.fill_buf = &fill_buf;
199 }
200
201 ret = resctrl_val(test, uparams, &param);
202 if (ret)
203 return ret;
204
205 ret = check_results();
206 if (ret && (get_vendor() == ARCH_INTEL) && !snc_kernel_support())
207 ksft_print_msg("Kernel doesn't support Sub-NUMA Clustering but it is enabled on the system.\n");
208
209 return ret;
210}
211
212static bool mba_feature_check(const struct resctrl_test *test)
213{
214 return test_resource_feature_check(test) &&
215 resctrl_mon_feature_exists("L3_MON", "mbm_local_bytes");
216}
217
218struct resctrl_test mba_test = {
219 .name = "MBA",
220 .resource = "MB",
221 .vendor_specific = ARCH_INTEL,
222 .feature_check = mba_feature_check,
223 .run_test = mba_run_test,
224 .cleanup = mba_test_cleanup,
225};