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1// SPDX-License-Identifier: GPL-2.0
2
3#include <stdint.h>
4#include "resctrl.h"
5
6char llc_occup_path[1024];
7
8void perf_event_attr_initialize(struct perf_event_attr *pea, __u64 config)
9{
10 memset(pea, 0, sizeof(*pea));
11 pea->type = PERF_TYPE_HARDWARE;
12 pea->size = sizeof(*pea);
13 pea->read_format = PERF_FORMAT_GROUP;
14 pea->exclude_kernel = 1;
15 pea->exclude_hv = 1;
16 pea->exclude_idle = 1;
17 pea->exclude_callchain_kernel = 1;
18 pea->inherit = 1;
19 pea->exclude_guest = 1;
20 pea->disabled = 1;
21 pea->config = config;
22}
23
24/* Start counters to log values */
25int perf_event_reset_enable(int pe_fd)
26{
27 int ret;
28
29 ret = ioctl(pe_fd, PERF_EVENT_IOC_RESET, 0);
30 if (ret < 0)
31 return ret;
32
33 ret = ioctl(pe_fd, PERF_EVENT_IOC_ENABLE, 0);
34 if (ret < 0)
35 return ret;
36
37 return 0;
38}
39
40void perf_event_initialize_read_format(struct perf_event_read *pe_read)
41{
42 memset(pe_read, 0, sizeof(*pe_read));
43 pe_read->nr = 1;
44}
45
46int perf_open(struct perf_event_attr *pea, pid_t pid, int cpu_no)
47{
48 int pe_fd;
49
50 pe_fd = perf_event_open(pea, pid, cpu_no, -1, PERF_FLAG_FD_CLOEXEC);
51 if (pe_fd == -1) {
52 ksft_perror("Error opening leader");
53 return -1;
54 }
55
56 perf_event_reset_enable(pe_fd);
57
58 return pe_fd;
59}
60
61/*
62 * Get LLC Occupancy as reported by RESCTRL FS
63 * For CMT,
64 * 1. If con_mon grp and mon grp given, then read from mon grp in
65 * con_mon grp
66 * 2. If only con_mon grp given, then read from con_mon grp
67 * 3. If both not given, then read from root con_mon grp
68 * For CAT,
69 * 1. If con_mon grp given, then read from it
70 * 2. If con_mon grp not given, then read from root con_mon grp
71 *
72 * Return: =0 on success. <0 on failure.
73 */
74static int get_llc_occu_resctrl(unsigned long *llc_occupancy)
75{
76 FILE *fp;
77
78 fp = fopen(llc_occup_path, "r");
79 if (!fp) {
80 ksft_perror("Failed to open results file");
81
82 return -1;
83 }
84 if (fscanf(fp, "%lu", llc_occupancy) <= 0) {
85 ksft_perror("Could not get llc occupancy");
86 fclose(fp);
87
88 return -1;
89 }
90 fclose(fp);
91
92 return 0;
93}
94
95/*
96 * print_results_cache: the cache results are stored in a file
97 * @filename: file that stores the results
98 * @bm_pid: child pid that runs benchmark
99 * @llc_value: perf miss value /
100 * llc occupancy value reported by resctrl FS
101 *
102 * Return: 0 on success, < 0 on error.
103 */
104static int print_results_cache(const char *filename, pid_t bm_pid, __u64 llc_value)
105{
106 FILE *fp;
107
108 if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
109 printf("Pid: %d \t LLC_value: %llu\n", (int)bm_pid, llc_value);
110 } else {
111 fp = fopen(filename, "a");
112 if (!fp) {
113 ksft_perror("Cannot open results file");
114
115 return -1;
116 }
117 fprintf(fp, "Pid: %d \t llc_value: %llu\n", (int)bm_pid, llc_value);
118 fclose(fp);
119 }
120
121 return 0;
122}
123
124/*
125 * perf_event_measure - Measure perf events
126 * @filename: Filename for writing the results
127 * @bm_pid: PID that runs the benchmark
128 *
129 * Measures perf events (e.g., cache misses) and writes the results into
130 * @filename. @bm_pid is written to the results file along with the measured
131 * value.
132 *
133 * Return: =0 on success. <0 on failure.
134 */
135int perf_event_measure(int pe_fd, struct perf_event_read *pe_read,
136 const char *filename, pid_t bm_pid)
137{
138 int ret;
139
140 /* Stop counters after one span to get miss rate */
141 ret = ioctl(pe_fd, PERF_EVENT_IOC_DISABLE, 0);
142 if (ret < 0)
143 return ret;
144
145 ret = read(pe_fd, pe_read, sizeof(*pe_read));
146 if (ret == -1) {
147 ksft_perror("Could not get perf value");
148 return -1;
149 }
150
151 return print_results_cache(filename, bm_pid, pe_read->values[0].value);
152}
153
154/*
155 * measure_llc_resctrl - Measure resctrl LLC value from resctrl
156 * @filename: Filename for writing the results
157 * @bm_pid: PID that runs the benchmark
158 *
159 * Measures LLC occupancy from resctrl and writes the results into @filename.
160 * @bm_pid is written to the results file along with the measured value.
161 *
162 * Return: =0 on success. <0 on failure.
163 */
164int measure_llc_resctrl(const char *filename, pid_t bm_pid)
165{
166 unsigned long llc_occu_resc = 0;
167 int ret;
168
169 ret = get_llc_occu_resctrl(&llc_occu_resc);
170 if (ret < 0)
171 return ret;
172
173 return print_results_cache(filename, bm_pid, llc_occu_resc);
174}
175
176/*
177 * show_cache_info - Show generic cache test information
178 * @no_of_bits: Number of bits
179 * @avg_llc_val: Average of LLC cache result data
180 * @cache_span: Cache span
181 * @lines: @cache_span in lines or bytes
182 */
183void show_cache_info(int no_of_bits, __u64 avg_llc_val, size_t cache_span, bool lines)
184{
185 ksft_print_msg("Number of bits: %d\n", no_of_bits);
186 ksft_print_msg("Average LLC val: %llu\n", avg_llc_val);
187 ksft_print_msg("Cache span (%s): %zu\n", lines ? "lines" : "bytes",
188 cache_span);
189}
1// SPDX-License-Identifier: GPL-2.0
2
3#include <stdint.h>
4#include "resctrl.h"
5
6struct read_format {
7 __u64 nr; /* The number of events */
8 struct {
9 __u64 value; /* The value of the event */
10 } values[2];
11};
12
13static struct perf_event_attr pea_llc_miss;
14static struct read_format rf_cqm;
15static int fd_lm;
16char llc_occup_path[1024];
17
18static void initialize_perf_event_attr(void)
19{
20 pea_llc_miss.type = PERF_TYPE_HARDWARE;
21 pea_llc_miss.size = sizeof(struct perf_event_attr);
22 pea_llc_miss.read_format = PERF_FORMAT_GROUP;
23 pea_llc_miss.exclude_kernel = 1;
24 pea_llc_miss.exclude_hv = 1;
25 pea_llc_miss.exclude_idle = 1;
26 pea_llc_miss.exclude_callchain_kernel = 1;
27 pea_llc_miss.inherit = 1;
28 pea_llc_miss.exclude_guest = 1;
29 pea_llc_miss.disabled = 1;
30}
31
32static void ioctl_perf_event_ioc_reset_enable(void)
33{
34 ioctl(fd_lm, PERF_EVENT_IOC_RESET, 0);
35 ioctl(fd_lm, PERF_EVENT_IOC_ENABLE, 0);
36}
37
38static int perf_event_open_llc_miss(pid_t pid, int cpu_no)
39{
40 fd_lm = perf_event_open(&pea_llc_miss, pid, cpu_no, -1,
41 PERF_FLAG_FD_CLOEXEC);
42 if (fd_lm == -1) {
43 perror("Error opening leader");
44 ctrlc_handler(0, NULL, NULL);
45 return -1;
46 }
47
48 return 0;
49}
50
51static void initialize_llc_perf(void)
52{
53 memset(&pea_llc_miss, 0, sizeof(struct perf_event_attr));
54 memset(&rf_cqm, 0, sizeof(struct read_format));
55
56 /* Initialize perf_event_attr structures for HW_CACHE_MISSES */
57 initialize_perf_event_attr();
58
59 pea_llc_miss.config = PERF_COUNT_HW_CACHE_MISSES;
60
61 rf_cqm.nr = 1;
62}
63
64static int reset_enable_llc_perf(pid_t pid, int cpu_no)
65{
66 int ret = 0;
67
68 ret = perf_event_open_llc_miss(pid, cpu_no);
69 if (ret < 0)
70 return ret;
71
72 /* Start counters to log values */
73 ioctl_perf_event_ioc_reset_enable();
74
75 return 0;
76}
77
78/*
79 * get_llc_perf: llc cache miss through perf events
80 * @llc_perf_miss: LLC miss counter that is filled on success
81 *
82 * Perf events like HW_CACHE_MISSES could be used to validate number of
83 * cache lines allocated.
84 *
85 * Return: =0 on success. <0 on failure.
86 */
87static int get_llc_perf(unsigned long *llc_perf_miss)
88{
89 __u64 total_misses;
90 int ret;
91
92 /* Stop counters after one span to get miss rate */
93
94 ioctl(fd_lm, PERF_EVENT_IOC_DISABLE, 0);
95
96 ret = read(fd_lm, &rf_cqm, sizeof(struct read_format));
97 if (ret == -1) {
98 perror("Could not get llc misses through perf");
99 return -1;
100 }
101
102 total_misses = rf_cqm.values[0].value;
103 *llc_perf_miss = total_misses;
104
105 return 0;
106}
107
108/*
109 * Get LLC Occupancy as reported by RESCTRL FS
110 * For CMT,
111 * 1. If con_mon grp and mon grp given, then read from mon grp in
112 * con_mon grp
113 * 2. If only con_mon grp given, then read from con_mon grp
114 * 3. If both not given, then read from root con_mon grp
115 * For CAT,
116 * 1. If con_mon grp given, then read from it
117 * 2. If con_mon grp not given, then read from root con_mon grp
118 *
119 * Return: =0 on success. <0 on failure.
120 */
121static int get_llc_occu_resctrl(unsigned long *llc_occupancy)
122{
123 FILE *fp;
124
125 fp = fopen(llc_occup_path, "r");
126 if (!fp) {
127 perror("Failed to open results file");
128
129 return errno;
130 }
131 if (fscanf(fp, "%lu", llc_occupancy) <= 0) {
132 perror("Could not get llc occupancy");
133 fclose(fp);
134
135 return -1;
136 }
137 fclose(fp);
138
139 return 0;
140}
141
142/*
143 * print_results_cache: the cache results are stored in a file
144 * @filename: file that stores the results
145 * @bm_pid: child pid that runs benchmark
146 * @llc_value: perf miss value /
147 * llc occupancy value reported by resctrl FS
148 *
149 * Return: 0 on success. non-zero on failure.
150 */
151static int print_results_cache(char *filename, int bm_pid,
152 unsigned long llc_value)
153{
154 FILE *fp;
155
156 if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
157 printf("Pid: %d \t LLC_value: %lu\n", bm_pid,
158 llc_value);
159 } else {
160 fp = fopen(filename, "a");
161 if (!fp) {
162 perror("Cannot open results file");
163
164 return errno;
165 }
166 fprintf(fp, "Pid: %d \t llc_value: %lu\n", bm_pid, llc_value);
167 fclose(fp);
168 }
169
170 return 0;
171}
172
173int measure_cache_vals(struct resctrl_val_param *param, int bm_pid)
174{
175 unsigned long llc_perf_miss = 0, llc_occu_resc = 0, llc_value = 0;
176 int ret;
177
178 /*
179 * Measure cache miss from perf.
180 */
181 if (!strncmp(param->resctrl_val, CAT_STR, sizeof(CAT_STR))) {
182 ret = get_llc_perf(&llc_perf_miss);
183 if (ret < 0)
184 return ret;
185 llc_value = llc_perf_miss;
186 }
187
188 /*
189 * Measure llc occupancy from resctrl.
190 */
191 if (!strncmp(param->resctrl_val, CMT_STR, sizeof(CMT_STR))) {
192 ret = get_llc_occu_resctrl(&llc_occu_resc);
193 if (ret < 0)
194 return ret;
195 llc_value = llc_occu_resc;
196 }
197 ret = print_results_cache(param->filename, bm_pid, llc_value);
198 if (ret)
199 return ret;
200
201 return 0;
202}
203
204/*
205 * cache_val: execute benchmark and measure LLC occupancy resctrl
206 * and perf cache miss for the benchmark
207 * @param: parameters passed to cache_val()
208 * @span: buffer size for the benchmark
209 *
210 * Return: 0 on success. non-zero on failure.
211 */
212int cat_val(struct resctrl_val_param *param, size_t span)
213{
214 int memflush = 1, operation = 0, ret = 0;
215 char *resctrl_val = param->resctrl_val;
216 pid_t bm_pid;
217
218 if (strcmp(param->filename, "") == 0)
219 sprintf(param->filename, "stdio");
220
221 bm_pid = getpid();
222
223 /* Taskset benchmark to specified cpu */
224 ret = taskset_benchmark(bm_pid, param->cpu_no);
225 if (ret)
226 return ret;
227
228 /* Write benchmark to specified con_mon grp, mon_grp in resctrl FS*/
229 ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
230 resctrl_val);
231 if (ret)
232 return ret;
233
234 initialize_llc_perf();
235
236 /* Test runs until the callback setup() tells the test to stop. */
237 while (1) {
238 ret = param->setup(param);
239 if (ret == END_OF_TESTS) {
240 ret = 0;
241 break;
242 }
243 if (ret < 0)
244 break;
245 ret = reset_enable_llc_perf(bm_pid, param->cpu_no);
246 if (ret)
247 break;
248
249 if (run_fill_buf(span, memflush, operation, true)) {
250 fprintf(stderr, "Error-running fill buffer\n");
251 ret = -1;
252 goto pe_close;
253 }
254
255 sleep(1);
256 ret = measure_cache_vals(param, bm_pid);
257 if (ret)
258 goto pe_close;
259 }
260
261 return ret;
262
263pe_close:
264 close(fd_lm);
265 return ret;
266}
267
268/*
269 * show_cache_info: show cache test result information
270 * @sum_llc_val: sum of LLC cache result data
271 * @no_of_bits: number of bits
272 * @cache_span: cache span in bytes for CMT or in lines for CAT
273 * @max_diff: max difference
274 * @max_diff_percent: max difference percentage
275 * @num_of_runs: number of runs
276 * @platform: show test information on this platform
277 * @cmt: CMT test or CAT test
278 *
279 * Return: 0 on success. non-zero on failure.
280 */
281int show_cache_info(unsigned long sum_llc_val, int no_of_bits,
282 size_t cache_span, unsigned long max_diff,
283 unsigned long max_diff_percent, unsigned long num_of_runs,
284 bool platform, bool cmt)
285{
286 unsigned long avg_llc_val = 0;
287 float diff_percent;
288 long avg_diff = 0;
289 int ret;
290
291 avg_llc_val = sum_llc_val / num_of_runs;
292 avg_diff = (long)abs(cache_span - avg_llc_val);
293 diff_percent = ((float)cache_span - avg_llc_val) / cache_span * 100;
294
295 ret = platform && abs((int)diff_percent) > max_diff_percent &&
296 (cmt ? (abs(avg_diff) > max_diff) : true);
297
298 ksft_print_msg("%s Check cache miss rate within %lu%%\n",
299 ret ? "Fail:" : "Pass:", max_diff_percent);
300
301 ksft_print_msg("Percent diff=%d\n", abs((int)diff_percent));
302 ksft_print_msg("Number of bits: %d\n", no_of_bits);
303 ksft_print_msg("Average LLC val: %lu\n", avg_llc_val);
304 ksft_print_msg("Cache span (%s): %zu\n", cmt ? "bytes" : "lines",
305 cache_span);
306
307 return ret;
308}