1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Memory bandwidth monitoring and allocation library
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 UNCORE_IMC "uncore_imc"
14 #define READ_FILE_NAME "events/cas_count_read"
15 #define WRITE_FILE_NAME "events/cas_count_write"
16 #define DYN_PMU_PATH "/sys/bus/event_source/devices"
17 #define SCALE 0.00006103515625
18 #define MAX_IMCS 20
19 #define MAX_TOKENS 5
20 #define READ 0
21 #define WRITE 1
22 #define CON_MON_MBM_LOCAL_BYTES_PATH \
23 "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
24
25 #define CON_MBM_LOCAL_BYTES_PATH \
26 "%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
27
28 #define MON_MBM_LOCAL_BYTES_PATH \
29 "%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
30
31 #define MBM_LOCAL_BYTES_PATH \
32 "%s/mon_data/mon_L3_%02d/mbm_local_bytes"
33
34 #define CON_MON_LCC_OCCUP_PATH \
35 "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
36
37 #define CON_LCC_OCCUP_PATH \
38 "%s/%s/mon_data/mon_L3_%02d/llc_occupancy"
39
40 #define MON_LCC_OCCUP_PATH \
41 "%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
42
43 #define LCC_OCCUP_PATH \
44 "%s/mon_data/mon_L3_%02d/llc_occupancy"
45
46 struct membw_read_format {
47 __u64 value; /* The value of the event */
48 __u64 time_enabled; /* if PERF_FORMAT_TOTAL_TIME_ENABLED */
49 __u64 time_running; /* if PERF_FORMAT_TOTAL_TIME_RUNNING */
50 __u64 id; /* if PERF_FORMAT_ID */
51 };
52
53 struct imc_counter_config {
54 __u32 type;
55 __u64 event;
56 __u64 umask;
57 struct perf_event_attr pe;
58 struct membw_read_format return_value;
59 int fd;
60 };
61
62 static char mbm_total_path[1024];
63 static int imcs;
64 static struct imc_counter_config imc_counters_config[MAX_IMCS][2];
65
membw_initialize_perf_event_attr(int i,int j)66 void membw_initialize_perf_event_attr(int i, int j)
67 {
68 memset(&imc_counters_config[i][j].pe, 0,
69 sizeof(struct perf_event_attr));
70 imc_counters_config[i][j].pe.type = imc_counters_config[i][j].type;
71 imc_counters_config[i][j].pe.size = sizeof(struct perf_event_attr);
72 imc_counters_config[i][j].pe.disabled = 1;
73 imc_counters_config[i][j].pe.inherit = 1;
74 imc_counters_config[i][j].pe.exclude_guest = 0;
75 imc_counters_config[i][j].pe.config =
76 imc_counters_config[i][j].umask << 8 |
77 imc_counters_config[i][j].event;
78 imc_counters_config[i][j].pe.sample_type = PERF_SAMPLE_IDENTIFIER;
79 imc_counters_config[i][j].pe.read_format =
80 PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING;
81 }
82
membw_ioctl_perf_event_ioc_reset_enable(int i,int j)83 void membw_ioctl_perf_event_ioc_reset_enable(int i, int j)
84 {
85 ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_RESET, 0);
86 ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_ENABLE, 0);
87 }
88
membw_ioctl_perf_event_ioc_disable(int i,int j)89 void membw_ioctl_perf_event_ioc_disable(int i, int j)
90 {
91 ioctl(imc_counters_config[i][j].fd, PERF_EVENT_IOC_DISABLE, 0);
92 }
93
94 /*
95 * get_event_and_umask: Parse config into event and umask
96 * @cas_count_cfg: Config
97 * @count: iMC number
98 * @op: Operation (read/write)
99 */
get_event_and_umask(char * cas_count_cfg,int count,bool op)100 void get_event_and_umask(char *cas_count_cfg, int count, bool op)
101 {
102 char *token[MAX_TOKENS];
103 int i = 0;
104
105 strcat(cas_count_cfg, ",");
106 token[0] = strtok(cas_count_cfg, "=,");
107
108 for (i = 1; i < MAX_TOKENS; i++)
109 token[i] = strtok(NULL, "=,");
110
111 for (i = 0; i < MAX_TOKENS; i++) {
112 if (!token[i])
113 break;
114 if (strcmp(token[i], "event") == 0) {
115 if (op == READ)
116 imc_counters_config[count][READ].event =
117 strtol(token[i + 1], NULL, 16);
118 else
119 imc_counters_config[count][WRITE].event =
120 strtol(token[i + 1], NULL, 16);
121 }
122 if (strcmp(token[i], "umask") == 0) {
123 if (op == READ)
124 imc_counters_config[count][READ].umask =
125 strtol(token[i + 1], NULL, 16);
126 else
127 imc_counters_config[count][WRITE].umask =
128 strtol(token[i + 1], NULL, 16);
129 }
130 }
131 }
132
open_perf_event(int i,int cpu_no,int j)133 static int open_perf_event(int i, int cpu_no, int j)
134 {
135 imc_counters_config[i][j].fd =
136 perf_event_open(&imc_counters_config[i][j].pe, -1, cpu_no, -1,
137 PERF_FLAG_FD_CLOEXEC);
138
139 if (imc_counters_config[i][j].fd == -1) {
140 fprintf(stderr, "Error opening leader %llx\n",
141 imc_counters_config[i][j].pe.config);
142
143 return -1;
144 }
145
146 return 0;
147 }
148
149 /* Get type and config (read and write) of an iMC counter */
read_from_imc_dir(char * imc_dir,int count)150 static int read_from_imc_dir(char *imc_dir, int count)
151 {
152 char cas_count_cfg[1024], imc_counter_cfg[1024], imc_counter_type[1024];
153 FILE *fp;
154
155 /* Get type of iMC counter */
156 sprintf(imc_counter_type, "%s%s", imc_dir, "type");
157 fp = fopen(imc_counter_type, "r");
158 if (!fp) {
159 perror("Failed to open imc counter type file");
160
161 return -1;
162 }
163 if (fscanf(fp, "%u", &imc_counters_config[count][READ].type) <= 0) {
164 perror("Could not get imc type");
165 fclose(fp);
166
167 return -1;
168 }
169 fclose(fp);
170
171 imc_counters_config[count][WRITE].type =
172 imc_counters_config[count][READ].type;
173
174 /* Get read config */
175 sprintf(imc_counter_cfg, "%s%s", imc_dir, READ_FILE_NAME);
176 fp = fopen(imc_counter_cfg, "r");
177 if (!fp) {
178 perror("Failed to open imc config file");
179
180 return -1;
181 }
182 if (fscanf(fp, "%s", cas_count_cfg) <= 0) {
183 perror("Could not get imc cas count read");
184 fclose(fp);
185
186 return -1;
187 }
188 fclose(fp);
189
190 get_event_and_umask(cas_count_cfg, count, READ);
191
192 /* Get write config */
193 sprintf(imc_counter_cfg, "%s%s", imc_dir, WRITE_FILE_NAME);
194 fp = fopen(imc_counter_cfg, "r");
195 if (!fp) {
196 perror("Failed to open imc config file");
197
198 return -1;
199 }
200 if (fscanf(fp, "%s", cas_count_cfg) <= 0) {
201 perror("Could not get imc cas count write");
202 fclose(fp);
203
204 return -1;
205 }
206 fclose(fp);
207
208 get_event_and_umask(cas_count_cfg, count, WRITE);
209
210 return 0;
211 }
212
213 /*
214 * A system can have 'n' number of iMC (Integrated Memory Controller)
215 * counters, get that 'n'. For each iMC counter get it's type and config.
216 * Also, each counter has two configs, one for read and the other for write.
217 * A config again has two parts, event and umask.
218 * Enumerate all these details into an array of structures.
219 *
220 * Return: >= 0 on success. < 0 on failure.
221 */
num_of_imcs(void)222 static int num_of_imcs(void)
223 {
224 char imc_dir[512], *temp;
225 unsigned int count = 0;
226 struct dirent *ep;
227 int ret;
228 DIR *dp;
229
230 dp = opendir(DYN_PMU_PATH);
231 if (dp) {
232 while ((ep = readdir(dp))) {
233 temp = strstr(ep->d_name, UNCORE_IMC);
234 if (!temp)
235 continue;
236
237 /*
238 * imc counters are named as "uncore_imc_<n>", hence
239 * increment the pointer to point to <n>. Note that
240 * sizeof(UNCORE_IMC) would count for null character as
241 * well and hence the last underscore character in
242 * uncore_imc'_' need not be counted.
243 */
244 temp = temp + sizeof(UNCORE_IMC);
245
246 /*
247 * Some directories under "DYN_PMU_PATH" could have
248 * names like "uncore_imc_free_running", hence, check if
249 * first character is a numerical digit or not.
250 */
251 if (temp[0] >= '0' && temp[0] <= '9') {
252 sprintf(imc_dir, "%s/%s/", DYN_PMU_PATH,
253 ep->d_name);
254 ret = read_from_imc_dir(imc_dir, count);
255 if (ret) {
256 closedir(dp);
257
258 return ret;
259 }
260 count++;
261 }
262 }
263 closedir(dp);
264 if (count == 0) {
265 perror("Unable find iMC counters!\n");
266
267 return -1;
268 }
269 } else {
270 perror("Unable to open PMU directory!\n");
271
272 return -1;
273 }
274
275 return count;
276 }
277
initialize_mem_bw_imc(void)278 static int initialize_mem_bw_imc(void)
279 {
280 int imc, j;
281
282 imcs = num_of_imcs();
283 if (imcs <= 0)
284 return imcs;
285
286 /* Initialize perf_event_attr structures for all iMC's */
287 for (imc = 0; imc < imcs; imc++) {
288 for (j = 0; j < 2; j++)
289 membw_initialize_perf_event_attr(imc, j);
290 }
291
292 return 0;
293 }
294
295 /*
296 * get_mem_bw_imc: Memory band width as reported by iMC counters
297 * @cpu_no: CPU number that the benchmark PID is binded to
298 * @bw_report: Bandwidth report type (reads, writes)
299 *
300 * Memory B/W utilized by a process on a socket can be calculated using
301 * iMC counters. Perf events are used to read these counters.
302 *
303 * Return: = 0 on success. < 0 on failure.
304 */
get_mem_bw_imc(int cpu_no,char * bw_report,float * bw_imc)305 static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
306 {
307 float reads, writes, of_mul_read, of_mul_write;
308 int imc, j, ret;
309
310 /* Start all iMC counters to log values (both read and write) */
311 reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
312 for (imc = 0; imc < imcs; imc++) {
313 for (j = 0; j < 2; j++) {
314 ret = open_perf_event(imc, cpu_no, j);
315 if (ret)
316 return -1;
317 }
318 for (j = 0; j < 2; j++)
319 membw_ioctl_perf_event_ioc_reset_enable(imc, j);
320 }
321
322 sleep(1);
323
324 /* Stop counters after a second to get results (both read and write) */
325 for (imc = 0; imc < imcs; imc++) {
326 for (j = 0; j < 2; j++)
327 membw_ioctl_perf_event_ioc_disable(imc, j);
328 }
329
330 /*
331 * Get results which are stored in struct type imc_counter_config
332 * Take over flow into consideration before calculating total b/w
333 */
334 for (imc = 0; imc < imcs; imc++) {
335 struct imc_counter_config *r =
336 &imc_counters_config[imc][READ];
337 struct imc_counter_config *w =
338 &imc_counters_config[imc][WRITE];
339
340 if (read(r->fd, &r->return_value,
341 sizeof(struct membw_read_format)) == -1) {
342 perror("Couldn't get read b/w through iMC");
343
344 return -1;
345 }
346
347 if (read(w->fd, &w->return_value,
348 sizeof(struct membw_read_format)) == -1) {
349 perror("Couldn't get write bw through iMC");
350
351 return -1;
352 }
353
354 __u64 r_time_enabled = r->return_value.time_enabled;
355 __u64 r_time_running = r->return_value.time_running;
356
357 if (r_time_enabled != r_time_running)
358 of_mul_read = (float)r_time_enabled /
359 (float)r_time_running;
360
361 __u64 w_time_enabled = w->return_value.time_enabled;
362 __u64 w_time_running = w->return_value.time_running;
363
364 if (w_time_enabled != w_time_running)
365 of_mul_write = (float)w_time_enabled /
366 (float)w_time_running;
367 reads += r->return_value.value * of_mul_read * SCALE;
368 writes += w->return_value.value * of_mul_write * SCALE;
369 }
370
371 for (imc = 0; imc < imcs; imc++) {
372 close(imc_counters_config[imc][READ].fd);
373 close(imc_counters_config[imc][WRITE].fd);
374 }
375
376 if (strcmp(bw_report, "reads") == 0) {
377 *bw_imc = reads;
378 return 0;
379 }
380
381 if (strcmp(bw_report, "writes") == 0) {
382 *bw_imc = writes;
383 return 0;
384 }
385
386 *bw_imc = reads + writes;
387 return 0;
388 }
389
set_mbm_path(const char * ctrlgrp,const char * mongrp,int resource_id)390 void set_mbm_path(const char *ctrlgrp, const char *mongrp, int resource_id)
391 {
392 if (ctrlgrp && mongrp)
393 sprintf(mbm_total_path, CON_MON_MBM_LOCAL_BYTES_PATH,
394 RESCTRL_PATH, ctrlgrp, mongrp, resource_id);
395 else if (!ctrlgrp && mongrp)
396 sprintf(mbm_total_path, MON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
397 mongrp, resource_id);
398 else if (ctrlgrp && !mongrp)
399 sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
400 ctrlgrp, resource_id);
401 else if (!ctrlgrp && !mongrp)
402 sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
403 resource_id);
404 }
405
406 /*
407 * initialize_mem_bw_resctrl: Appropriately populate "mbm_total_path"
408 * @ctrlgrp: Name of the control monitor group (con_mon grp)
409 * @mongrp: Name of the monitor group (mon grp)
410 * @cpu_no: CPU number that the benchmark PID is binded to
411 * @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
412 */
initialize_mem_bw_resctrl(const char * ctrlgrp,const char * mongrp,int cpu_no,char * resctrl_val)413 static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
414 int cpu_no, char *resctrl_val)
415 {
416 int resource_id;
417
418 if (get_resource_id(cpu_no, &resource_id) < 0) {
419 perror("Could not get resource_id");
420 return;
421 }
422
423 if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
424 set_mbm_path(ctrlgrp, mongrp, resource_id);
425
426 if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
427 if (ctrlgrp)
428 sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH,
429 RESCTRL_PATH, ctrlgrp, resource_id);
430 else
431 sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH,
432 RESCTRL_PATH, resource_id);
433 }
434 }
435
436 /*
437 * Get MBM Local bytes as reported by resctrl FS
438 * For MBM,
439 * 1. If con_mon grp and mon grp are given, then read from con_mon grp's mon grp
440 * 2. If only con_mon grp is given, then read from con_mon grp
441 * 3. If both are not given, then read from root con_mon grp
442 * For MBA,
443 * 1. If con_mon grp is given, then read from it
444 * 2. If con_mon grp is not given, then read from root con_mon grp
445 */
get_mem_bw_resctrl(unsigned long * mbm_total)446 static int get_mem_bw_resctrl(unsigned long *mbm_total)
447 {
448 FILE *fp;
449
450 fp = fopen(mbm_total_path, "r");
451 if (!fp) {
452 perror("Failed to open total bw file");
453
454 return -1;
455 }
456 if (fscanf(fp, "%lu", mbm_total) <= 0) {
457 perror("Could not get mbm local bytes");
458 fclose(fp);
459
460 return -1;
461 }
462 fclose(fp);
463
464 return 0;
465 }
466
467 pid_t bm_pid, ppid;
468
ctrlc_handler(int signum,siginfo_t * info,void * ptr)469 void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
470 {
471 kill(bm_pid, SIGKILL);
472 umount_resctrlfs();
473 tests_cleanup();
474 printf("Ending\n\n");
475
476 exit(EXIT_SUCCESS);
477 }
478
479 /*
480 * print_results_bw: the memory bandwidth results are stored in a file
481 * @filename: file that stores the results
482 * @bm_pid: child pid that runs benchmark
483 * @bw_imc: perf imc counter value
484 * @bw_resc: memory bandwidth value
485 *
486 * Return: 0 on success. non-zero on failure.
487 */
print_results_bw(char * filename,int bm_pid,float bw_imc,unsigned long bw_resc)488 static int print_results_bw(char *filename, int bm_pid, float bw_imc,
489 unsigned long bw_resc)
490 {
491 unsigned long diff = fabs(bw_imc - bw_resc);
492 FILE *fp;
493
494 if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
495 printf("Pid: %d \t Mem_BW_iMC: %f \t ", bm_pid, bw_imc);
496 printf("Mem_BW_resc: %lu \t Difference: %lu\n", bw_resc, diff);
497 } else {
498 fp = fopen(filename, "a");
499 if (!fp) {
500 perror("Cannot open results file");
501
502 return errno;
503 }
504 if (fprintf(fp, "Pid: %d \t Mem_BW_iMC: %f \t Mem_BW_resc: %lu \t Difference: %lu\n",
505 bm_pid, bw_imc, bw_resc, diff) <= 0) {
506 fclose(fp);
507 perror("Could not log results.");
508
509 return errno;
510 }
511 fclose(fp);
512 }
513
514 return 0;
515 }
516
set_cqm_path(const char * ctrlgrp,const char * mongrp,char sock_num)517 static void set_cqm_path(const char *ctrlgrp, const char *mongrp, char sock_num)
518 {
519 if (strlen(ctrlgrp) && strlen(mongrp))
520 sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
521 ctrlgrp, mongrp, sock_num);
522 else if (!strlen(ctrlgrp) && strlen(mongrp))
523 sprintf(llc_occup_path, MON_LCC_OCCUP_PATH, RESCTRL_PATH,
524 mongrp, sock_num);
525 else if (strlen(ctrlgrp) && !strlen(mongrp))
526 sprintf(llc_occup_path, CON_LCC_OCCUP_PATH, RESCTRL_PATH,
527 ctrlgrp, sock_num);
528 else if (!strlen(ctrlgrp) && !strlen(mongrp))
529 sprintf(llc_occup_path, LCC_OCCUP_PATH, RESCTRL_PATH, sock_num);
530 }
531
532 /*
533 * initialize_llc_occu_resctrl: Appropriately populate "llc_occup_path"
534 * @ctrlgrp: Name of the control monitor group (con_mon grp)
535 * @mongrp: Name of the monitor group (mon grp)
536 * @cpu_no: CPU number that the benchmark PID is binded to
537 * @resctrl_val: Resctrl feature (Eg: cat, cqm.. etc)
538 */
initialize_llc_occu_resctrl(const char * ctrlgrp,const char * mongrp,int cpu_no,char * resctrl_val)539 static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
540 int cpu_no, char *resctrl_val)
541 {
542 int resource_id;
543
544 if (get_resource_id(cpu_no, &resource_id) < 0) {
545 perror("# Unable to resource_id");
546 return;
547 }
548
549 if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
550 set_cqm_path(ctrlgrp, mongrp, resource_id);
551 }
552
553 static int
measure_vals(struct resctrl_val_param * param,unsigned long * bw_resc_start)554 measure_vals(struct resctrl_val_param *param, unsigned long *bw_resc_start)
555 {
556 unsigned long bw_resc, bw_resc_end;
557 float bw_imc;
558 int ret;
559
560 /*
561 * Measure memory bandwidth from resctrl and from
562 * another source which is perf imc value or could
563 * be something else if perf imc event is not available.
564 * Compare the two values to validate resctrl value.
565 * It takes 1sec to measure the data.
566 */
567 ret = get_mem_bw_imc(param->cpu_no, param->bw_report, &bw_imc);
568 if (ret < 0)
569 return ret;
570
571 ret = get_mem_bw_resctrl(&bw_resc_end);
572 if (ret < 0)
573 return ret;
574
575 bw_resc = (bw_resc_end - *bw_resc_start) / MB;
576 ret = print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
577 if (ret)
578 return ret;
579
580 *bw_resc_start = bw_resc_end;
581
582 return 0;
583 }
584
585 /*
586 * resctrl_val: execute benchmark and measure memory bandwidth on
587 * the benchmark
588 * @benchmark_cmd: benchmark command and its arguments
589 * @param: parameters passed to resctrl_val()
590 *
591 * Return: 0 on success. non-zero on failure.
592 */
resctrl_val(char ** benchmark_cmd,struct resctrl_val_param * param)593 int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param)
594 {
595 char *resctrl_val = param->resctrl_val;
596 unsigned long bw_resc_start = 0;
597 struct sigaction sigact;
598 int ret = 0, pipefd[2];
599 char pipe_message = 0;
600 union sigval value;
601
602 if (strcmp(param->filename, "") == 0)
603 sprintf(param->filename, "stdio");
604
605 if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
606 !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
607 ret = validate_bw_report_request(param->bw_report);
608 if (ret)
609 return ret;
610 }
611
612 ret = remount_resctrlfs(param->mum_resctrlfs);
613 if (ret)
614 return ret;
615
616 /*
617 * If benchmark wasn't successfully started by child, then child should
618 * kill parent, so save parent's pid
619 */
620 ppid = getpid();
621
622 if (pipe(pipefd)) {
623 perror("# Unable to create pipe");
624
625 return -1;
626 }
627
628 /*
629 * Fork to start benchmark, save child's pid so that it can be killed
630 * when needed
631 */
632 bm_pid = fork();
633 if (bm_pid == -1) {
634 perror("# Unable to fork");
635
636 return -1;
637 }
638
639 if (bm_pid == 0) {
640 /*
641 * Mask all signals except SIGUSR1, parent uses SIGUSR1 to
642 * start benchmark
643 */
644 sigfillset(&sigact.sa_mask);
645 sigdelset(&sigact.sa_mask, SIGUSR1);
646
647 sigact.sa_sigaction = run_benchmark;
648 sigact.sa_flags = SA_SIGINFO;
649
650 /* Register for "SIGUSR1" signal from parent */
651 if (sigaction(SIGUSR1, &sigact, NULL))
652 PARENT_EXIT("Can't register child for signal");
653
654 /* Tell parent that child is ready */
655 close(pipefd[0]);
656 pipe_message = 1;
657 if (write(pipefd[1], &pipe_message, sizeof(pipe_message)) <
658 sizeof(pipe_message)) {
659 perror("# failed signaling parent process");
660 close(pipefd[1]);
661 return -1;
662 }
663 close(pipefd[1]);
664
665 /* Suspend child until delivery of "SIGUSR1" from parent */
666 sigsuspend(&sigact.sa_mask);
667
668 PARENT_EXIT("Child is done");
669 }
670
671 printf("# benchmark PID: %d\n", bm_pid);
672
673 /*
674 * Register CTRL-C handler for parent, as it has to kill benchmark
675 * before exiting
676 */
677 sigact.sa_sigaction = ctrlc_handler;
678 sigemptyset(&sigact.sa_mask);
679 sigact.sa_flags = SA_SIGINFO;
680 if (sigaction(SIGINT, &sigact, NULL) ||
681 sigaction(SIGHUP, &sigact, NULL)) {
682 perror("# sigaction");
683 ret = errno;
684 goto out;
685 }
686
687 value.sival_ptr = benchmark_cmd;
688
689 /* Taskset benchmark to specified cpu */
690 ret = taskset_benchmark(bm_pid, param->cpu_no);
691 if (ret)
692 goto out;
693
694 /* Write benchmark to specified control&monitoring grp in resctrl FS */
695 ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
696 resctrl_val);
697 if (ret)
698 goto out;
699
700 if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
701 !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
702 ret = initialize_mem_bw_imc();
703 if (ret)
704 goto out;
705
706 initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
707 param->cpu_no, resctrl_val);
708 } else if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
709 initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
710 param->cpu_no, resctrl_val);
711
712 /* Parent waits for child to be ready. */
713 close(pipefd[1]);
714 while (pipe_message != 1) {
715 if (read(pipefd[0], &pipe_message, sizeof(pipe_message)) <
716 sizeof(pipe_message)) {
717 perror("# failed reading message from child process");
718 close(pipefd[0]);
719 goto out;
720 }
721 }
722 close(pipefd[0]);
723
724 /* Signal child to start benchmark */
725 if (sigqueue(bm_pid, SIGUSR1, value) == -1) {
726 perror("# sigqueue SIGUSR1 to child");
727 ret = errno;
728 goto out;
729 }
730
731 /* Give benchmark enough time to fully run */
732 sleep(1);
733
734 /* Test runs until the callback setup() tells the test to stop. */
735 while (1) {
736 if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
737 !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
738 ret = param->setup(1, param);
739 if (ret) {
740 ret = 0;
741 break;
742 }
743
744 ret = measure_vals(param, &bw_resc_start);
745 if (ret)
746 break;
747 } else if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR))) {
748 ret = param->setup(1, param);
749 if (ret) {
750 ret = 0;
751 break;
752 }
753 sleep(1);
754 ret = measure_cache_vals(param, bm_pid);
755 if (ret)
756 break;
757 } else {
758 break;
759 }
760 }
761
762 out:
763 kill(bm_pid, SIGKILL);
764 umount_resctrlfs();
765
766 return ret;
767 }
768