1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Cache Monitoring Technology (CMT) 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 #include <unistd.h>
13
14 #define RESULT_FILE_NAME "result_cmt"
15 #define NUM_OF_RUNS 5
16 #define MAX_DIFF 2000000
17 #define MAX_DIFF_PERCENT 15
18
19 #define CON_MON_LCC_OCCUP_PATH \
20 "%s/%s/mon_data/mon_L3_%02d/llc_occupancy"
21
22 static int cmt_init(const struct resctrl_val_param *param, int domain_id)
23 {
24 sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
25 param->ctrlgrp, domain_id);
26
27 return 0;
28 }
29
30 static int cmt_setup(const struct resctrl_test *test,
31 const struct user_params *uparams,
32 struct resctrl_val_param *p)
33 {
34 /* Run NUM_OF_RUNS times */
35 if (p->num_of_runs >= NUM_OF_RUNS)
36 return END_OF_TESTS;
37
38 p->num_of_runs++;
39
40 return 0;
41 }
42
43 static int cmt_measure(const struct user_params *uparams,
44 struct resctrl_val_param *param, pid_t bm_pid)
45 {
46 sleep(1);
47 return measure_llc_resctrl(param->filename, bm_pid);
48 }
49
50 static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
51 unsigned long cache_span, unsigned long max_diff,
52 unsigned long max_diff_percent, unsigned long num_of_runs,
53 bool platform)
54 {
55 unsigned long avg_llc_val = 0;
56 float diff_percent;
57 long avg_diff = 0;
58 int ret;
59
60 avg_llc_val = sum_llc_val / num_of_runs;
61 avg_diff = (long)(cache_span - avg_llc_val);
62 diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100;
63
64 ret = platform && abs((int)diff_percent) > max_diff_percent &&
65 labs(avg_diff) > max_diff;
66
67 ksft_print_msg("%s Check cache miss rate within %lu%%\n",
68 ret ? "Fail:" : "Pass:", max_diff_percent);
69
70 ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));
71
72 show_cache_info(no_of_bits, avg_llc_val, cache_span, false);
73
74 return ret;
75 }
76
77 static int check_results(struct resctrl_val_param *param, size_t span, int no_of_bits)
78 {
79 char *token_array[8], temp[512];
80 unsigned long sum_llc_occu_resc = 0;
81 int runs = 0;
82 FILE *fp;
83
84 ksft_print_msg("Checking for pass/fail\n");
85 fp = fopen(param->filename, "r");
86 if (!fp) {
87 ksft_perror("Error in opening file");
88
89 return -1;
90 }
91
92 while (fgets(temp, sizeof(temp), fp)) {
93 char *token = strtok(temp, ":\t");
94 int fields = 0;
95
96 while (token) {
97 token_array[fields++] = token;
98 token = strtok(NULL, ":\t");
99 }
100
101 /* Field 3 is llc occ resc value */
102 if (runs > 0)
103 sum_llc_occu_resc += strtoul(token_array[3], NULL, 0);
104 runs++;
105 }
106 fclose(fp);
107
108 return show_results_info(sum_llc_occu_resc, no_of_bits, span,
109 MAX_DIFF, MAX_DIFF_PERCENT, runs - 1, true);
110 }
111
112 static void cmt_test_cleanup(void)
113 {
114 remove(RESULT_FILE_NAME);
115 }
116
117 static int cmt_run_test(const struct resctrl_test *test, const struct user_params *uparams)
118 {
119 const char * const *cmd = uparams->benchmark_cmd;
120 const char *new_cmd[BENCHMARK_ARGS];
121 unsigned long cache_total_size = 0;
122 int n = uparams->bits ? : 5;
123 unsigned long long_mask;
124 char *span_str = NULL;
125 int count_of_bits;
126 size_t span;
127 int ret, i;
128
129 ret = get_full_cbm("L3", &long_mask);
130 if (ret)
131 return ret;
132
133 ret = get_cache_size(uparams->cpu, "L3", &cache_total_size);
134 if (ret)
135 return ret;
136 ksft_print_msg("Cache size :%lu\n", cache_total_size);
137
138 count_of_bits = count_bits(long_mask);
139
140 if (n < 1 || n > count_of_bits) {
141 ksft_print_msg("Invalid input value for numbr_of_bits n!\n");
142 ksft_print_msg("Please enter value in range 1 to %d\n", count_of_bits);
143 return -1;
144 }
145
146 struct resctrl_val_param param = {
147 .ctrlgrp = "c1",
148 .filename = RESULT_FILE_NAME,
149 .mask = ~(long_mask << n) & long_mask,
150 .num_of_runs = 0,
151 .init = cmt_init,
152 .setup = cmt_setup,
153 .measure = cmt_measure,
154 };
155
156 span = cache_portion_size(cache_total_size, param.mask, long_mask);
157
158 if (strcmp(cmd[0], "fill_buf") == 0) {
159 /* Duplicate the command to be able to replace span in it */
160 for (i = 0; uparams->benchmark_cmd[i]; i++)
161 new_cmd[i] = uparams->benchmark_cmd[i];
162 new_cmd[i] = NULL;
163
164 ret = asprintf(&span_str, "%zu", span);
165 if (ret < 0)
166 return -1;
167 new_cmd[1] = span_str;
168 cmd = new_cmd;
169 }
170
171 remove(RESULT_FILE_NAME);
172
173 ret = resctrl_val(test, uparams, cmd, ¶m);
174 if (ret)
175 goto out;
176
177 ret = check_results(¶m, span, n);
178 if (ret && (get_vendor() == ARCH_INTEL))
179 ksft_print_msg("Intel CMT may be inaccurate when Sub-NUMA Clustering is enabled. Check BIOS configuration.\n");
180
181 out:
182 free(span_str);
183
184 return ret;
185 }
186
187 static bool cmt_feature_check(const struct resctrl_test *test)
188 {
189 return test_resource_feature_check(test) &&
190 resctrl_mon_feature_exists("L3_MON", "llc_occupancy");
191 }
192
193 struct resctrl_test cmt_test = {
194 .name = "CMT",
195 .resource = "L3",
196 .feature_check = cmt_feature_check,
197 .run_test = cmt_run_test,
198 .cleanup = cmt_test_cleanup,
199 };
200
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