• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Basic resctrl file system operations
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 int tests_run;
14 
find_resctrl_mount(char * buffer)15 static int find_resctrl_mount(char *buffer)
16 {
17 	FILE *mounts;
18 	char line[256], *fs, *mntpoint;
19 
20 	mounts = fopen("/proc/mounts", "r");
21 	if (!mounts) {
22 		perror("/proc/mounts");
23 		return -ENXIO;
24 	}
25 	while (!feof(mounts)) {
26 		if (!fgets(line, 256, mounts))
27 			break;
28 		fs = strtok(line, " \t");
29 		if (!fs)
30 			continue;
31 		mntpoint = strtok(NULL, " \t");
32 		if (!mntpoint)
33 			continue;
34 		fs = strtok(NULL, " \t");
35 		if (!fs)
36 			continue;
37 		if (strcmp(fs, "resctrl"))
38 			continue;
39 
40 		fclose(mounts);
41 		if (buffer)
42 			strncpy(buffer, mntpoint, 256);
43 
44 		return 0;
45 	}
46 
47 	fclose(mounts);
48 
49 	return -ENOENT;
50 }
51 
52 /*
53  * remount_resctrlfs - Remount resctrl FS at /sys/fs/resctrl
54  * @mum_resctrlfs:	Should the resctrl FS be remounted?
55  *
56  * If not mounted, mount it.
57  * If mounted and mum_resctrlfs then remount resctrl FS.
58  * If mounted and !mum_resctrlfs then noop
59  *
60  * Return: 0 on success, non-zero on failure
61  */
remount_resctrlfs(bool mum_resctrlfs)62 int remount_resctrlfs(bool mum_resctrlfs)
63 {
64 	char mountpoint[256];
65 	int ret;
66 
67 	ret = find_resctrl_mount(mountpoint);
68 	if (ret)
69 		strcpy(mountpoint, RESCTRL_PATH);
70 
71 	if (!ret && mum_resctrlfs && umount(mountpoint)) {
72 		printf("not ok unmounting \"%s\"\n", mountpoint);
73 		perror("# umount");
74 		tests_run++;
75 	}
76 
77 	if (!ret && !mum_resctrlfs)
78 		return 0;
79 
80 	ret = mount("resctrl", RESCTRL_PATH, "resctrl", 0, NULL);
81 	printf("%sok mounting resctrl to \"%s\"\n", ret ? "not " : "",
82 	       RESCTRL_PATH);
83 	if (ret)
84 		perror("# mount");
85 
86 	tests_run++;
87 
88 	return ret;
89 }
90 
umount_resctrlfs(void)91 int umount_resctrlfs(void)
92 {
93 	if (umount(RESCTRL_PATH)) {
94 		perror("# Unable to umount resctrl");
95 
96 		return errno;
97 	}
98 
99 	return 0;
100 }
101 
102 /*
103  * get_resource_id - Get socket number/l3 id for a specified CPU
104  * @cpu_no:	CPU number
105  * @resource_id: Socket number or l3_id
106  *
107  * Return: >= 0 on success, < 0 on failure.
108  */
get_resource_id(int cpu_no,int * resource_id)109 int get_resource_id(int cpu_no, int *resource_id)
110 {
111 	char phys_pkg_path[1024];
112 	FILE *fp;
113 
114 	if (is_amd)
115 		sprintf(phys_pkg_path, "%s%d/cache/index3/id",
116 			PHYS_ID_PATH, cpu_no);
117 	else
118 		sprintf(phys_pkg_path, "%s%d/topology/physical_package_id",
119 			PHYS_ID_PATH, cpu_no);
120 
121 	fp = fopen(phys_pkg_path, "r");
122 	if (!fp) {
123 		perror("Failed to open physical_package_id");
124 
125 		return -1;
126 	}
127 	if (fscanf(fp, "%d", resource_id) <= 0) {
128 		perror("Could not get socket number or l3 id");
129 		fclose(fp);
130 
131 		return -1;
132 	}
133 	fclose(fp);
134 
135 	return 0;
136 }
137 
138 /*
139  * get_cache_size - Get cache size for a specified CPU
140  * @cpu_no:	CPU number
141  * @cache_type:	Cache level L2/L3
142  * @cache_size:	pointer to cache_size
143  *
144  * Return: = 0 on success, < 0 on failure.
145  */
get_cache_size(int cpu_no,char * cache_type,unsigned long * cache_size)146 int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size)
147 {
148 	char cache_path[1024], cache_str[64];
149 	int length, i, cache_num;
150 	FILE *fp;
151 
152 	if (!strcmp(cache_type, "L3")) {
153 		cache_num = 3;
154 	} else if (!strcmp(cache_type, "L2")) {
155 		cache_num = 2;
156 	} else {
157 		perror("Invalid cache level");
158 		return -1;
159 	}
160 
161 	sprintf(cache_path, "/sys/bus/cpu/devices/cpu%d/cache/index%d/size",
162 		cpu_no, cache_num);
163 	fp = fopen(cache_path, "r");
164 	if (!fp) {
165 		perror("Failed to open cache size");
166 
167 		return -1;
168 	}
169 	if (fscanf(fp, "%s", cache_str) <= 0) {
170 		perror("Could not get cache_size");
171 		fclose(fp);
172 
173 		return -1;
174 	}
175 	fclose(fp);
176 
177 	length = (int)strlen(cache_str);
178 
179 	*cache_size = 0;
180 
181 	for (i = 0; i < length; i++) {
182 		if ((cache_str[i] >= '0') && (cache_str[i] <= '9'))
183 
184 			*cache_size = *cache_size * 10 + (cache_str[i] - '0');
185 
186 		else if (cache_str[i] == 'K')
187 
188 			*cache_size = *cache_size * 1024;
189 
190 		else if (cache_str[i] == 'M')
191 
192 			*cache_size = *cache_size * 1024 * 1024;
193 
194 		else
195 			break;
196 	}
197 
198 	return 0;
199 }
200 
201 #define CORE_SIBLINGS_PATH	"/sys/bus/cpu/devices/cpu"
202 
203 /*
204  * get_cbm_mask - Get cbm mask for given cache
205  * @cache_type:	Cache level L2/L3
206  * @cbm_mask:	cbm_mask returned as a string
207  *
208  * Return: = 0 on success, < 0 on failure.
209  */
get_cbm_mask(char * cache_type,char * cbm_mask)210 int get_cbm_mask(char *cache_type, char *cbm_mask)
211 {
212 	char cbm_mask_path[1024];
213 	FILE *fp;
214 
215 	if (!cbm_mask)
216 		return -1;
217 
218 	sprintf(cbm_mask_path, "%s/%s/cbm_mask", CBM_MASK_PATH, cache_type);
219 
220 	fp = fopen(cbm_mask_path, "r");
221 	if (!fp) {
222 		perror("Failed to open cache level");
223 
224 		return -1;
225 	}
226 	if (fscanf(fp, "%s", cbm_mask) <= 0) {
227 		perror("Could not get max cbm_mask");
228 		fclose(fp);
229 
230 		return -1;
231 	}
232 	fclose(fp);
233 
234 	return 0;
235 }
236 
237 /*
238  * get_core_sibling - Get sibling core id from the same socket for given CPU
239  * @cpu_no:	CPU number
240  *
241  * Return:	> 0 on success, < 0 on failure.
242  */
get_core_sibling(int cpu_no)243 int get_core_sibling(int cpu_no)
244 {
245 	char core_siblings_path[1024], cpu_list_str[64];
246 	int sibling_cpu_no = -1;
247 	FILE *fp;
248 
249 	sprintf(core_siblings_path, "%s%d/topology/core_siblings_list",
250 		CORE_SIBLINGS_PATH, cpu_no);
251 
252 	fp = fopen(core_siblings_path, "r");
253 	if (!fp) {
254 		perror("Failed to open core siblings path");
255 
256 		return -1;
257 	}
258 	if (fscanf(fp, "%s", cpu_list_str) <= 0) {
259 		perror("Could not get core_siblings list");
260 		fclose(fp);
261 
262 		return -1;
263 	}
264 	fclose(fp);
265 
266 	char *token = strtok(cpu_list_str, "-,");
267 
268 	while (token) {
269 		sibling_cpu_no = atoi(token);
270 		/* Skipping core 0 as we don't want to run test on core 0 */
271 		if (sibling_cpu_no != 0)
272 			break;
273 		token = strtok(NULL, "-,");
274 	}
275 
276 	return sibling_cpu_no;
277 }
278 
279 /*
280  * taskset_benchmark - Taskset PID (i.e. benchmark) to a specified cpu
281  * @bm_pid:	PID that should be binded
282  * @cpu_no:	CPU number at which the PID would be binded
283  *
284  * Return: 0 on success, non-zero on failure
285  */
taskset_benchmark(pid_t bm_pid,int cpu_no)286 int taskset_benchmark(pid_t bm_pid, int cpu_no)
287 {
288 	cpu_set_t my_set;
289 
290 	CPU_ZERO(&my_set);
291 	CPU_SET(cpu_no, &my_set);
292 
293 	if (sched_setaffinity(bm_pid, sizeof(cpu_set_t), &my_set)) {
294 		perror("Unable to taskset benchmark");
295 
296 		return -1;
297 	}
298 
299 	return 0;
300 }
301 
302 /*
303  * run_benchmark - Run a specified benchmark or fill_buf (default benchmark)
304  *		   in specified signal. Direct benchmark stdio to /dev/null.
305  * @signum:	signal number
306  * @info:	signal info
307  * @ucontext:	user context in signal handling
308  *
309  * Return: void
310  */
run_benchmark(int signum,siginfo_t * info,void * ucontext)311 void run_benchmark(int signum, siginfo_t *info, void *ucontext)
312 {
313 	int operation, ret, malloc_and_init_memory, memflush;
314 	unsigned long span, buffer_span;
315 	char **benchmark_cmd;
316 	char resctrl_val[64];
317 	FILE *fp;
318 
319 	benchmark_cmd = info->si_ptr;
320 
321 	/*
322 	 * Direct stdio of child to /dev/null, so that only parent writes to
323 	 * stdio (console)
324 	 */
325 	fp = freopen("/dev/null", "w", stdout);
326 	if (!fp)
327 		PARENT_EXIT("Unable to direct benchmark status to /dev/null");
328 
329 	if (strcmp(benchmark_cmd[0], "fill_buf") == 0) {
330 		/* Execute default fill_buf benchmark */
331 		span = strtoul(benchmark_cmd[1], NULL, 10);
332 		malloc_and_init_memory = atoi(benchmark_cmd[2]);
333 		memflush =  atoi(benchmark_cmd[3]);
334 		operation = atoi(benchmark_cmd[4]);
335 		sprintf(resctrl_val, "%s", benchmark_cmd[5]);
336 
337 		if (strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
338 			buffer_span = span * MB;
339 		else
340 			buffer_span = span;
341 
342 		if (run_fill_buf(buffer_span, malloc_and_init_memory, memflush,
343 				 operation, resctrl_val))
344 			fprintf(stderr, "Error in running fill buffer\n");
345 	} else {
346 		/* Execute specified benchmark */
347 		ret = execvp(benchmark_cmd[0], benchmark_cmd);
348 		if (ret)
349 			perror("wrong\n");
350 	}
351 
352 	fclose(stdout);
353 	PARENT_EXIT("Unable to run specified benchmark");
354 }
355 
356 /*
357  * create_grp - Create a group only if one doesn't exist
358  * @grp_name:	Name of the group
359  * @grp:	Full path and name of the group
360  * @parent_grp:	Full path and name of the parent group
361  *
362  * Return: 0 on success, non-zero on failure
363  */
create_grp(const char * grp_name,char * grp,const char * parent_grp)364 static int create_grp(const char *grp_name, char *grp, const char *parent_grp)
365 {
366 	int found_grp = 0;
367 	struct dirent *ep;
368 	DIR *dp;
369 
370 	/*
371 	 * At this point, we are guaranteed to have resctrl FS mounted and if
372 	 * length of grp_name == 0, it means, user wants to use root con_mon
373 	 * grp, so do nothing
374 	 */
375 	if (strlen(grp_name) == 0)
376 		return 0;
377 
378 	/* Check if requested grp exists or not */
379 	dp = opendir(parent_grp);
380 	if (dp) {
381 		while ((ep = readdir(dp)) != NULL) {
382 			if (strcmp(ep->d_name, grp_name) == 0)
383 				found_grp = 1;
384 		}
385 		closedir(dp);
386 	} else {
387 		perror("Unable to open resctrl for group");
388 
389 		return -1;
390 	}
391 
392 	/* Requested grp doesn't exist, hence create it */
393 	if (found_grp == 0) {
394 		if (mkdir(grp, 0) == -1) {
395 			perror("Unable to create group");
396 
397 			return -1;
398 		}
399 	}
400 
401 	return 0;
402 }
403 
write_pid_to_tasks(char * tasks,pid_t pid)404 static int write_pid_to_tasks(char *tasks, pid_t pid)
405 {
406 	FILE *fp;
407 
408 	fp = fopen(tasks, "w");
409 	if (!fp) {
410 		perror("Failed to open tasks file");
411 
412 		return -1;
413 	}
414 	if (fprintf(fp, "%d\n", pid) < 0) {
415 		perror("Failed to wr pid to tasks file");
416 		fclose(fp);
417 
418 		return -1;
419 	}
420 	fclose(fp);
421 
422 	return 0;
423 }
424 
425 /*
426  * write_bm_pid_to_resctrl - Write a PID (i.e. benchmark) to resctrl FS
427  * @bm_pid:		PID that should be written
428  * @ctrlgrp:		Name of the control monitor group (con_mon grp)
429  * @mongrp:		Name of the monitor group (mon grp)
430  * @resctrl_val:	Resctrl feature (Eg: mbm, mba.. etc)
431  *
432  * If a con_mon grp is requested, create it and write pid to it, otherwise
433  * write pid to root con_mon grp.
434  * If a mon grp is requested, create it and write pid to it, otherwise
435  * pid is not written, this means that pid is in con_mon grp and hence
436  * should consult con_mon grp's mon_data directory for results.
437  *
438  * Return: 0 on success, non-zero on failure
439  */
write_bm_pid_to_resctrl(pid_t bm_pid,char * ctrlgrp,char * mongrp,char * resctrl_val)440 int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
441 			    char *resctrl_val)
442 {
443 	char controlgroup[128], monitorgroup[512], monitorgroup_p[256];
444 	char tasks[1024];
445 	int ret = 0;
446 
447 	if (strlen(ctrlgrp))
448 		sprintf(controlgroup, "%s/%s", RESCTRL_PATH, ctrlgrp);
449 	else
450 		sprintf(controlgroup, "%s", RESCTRL_PATH);
451 
452 	/* Create control and monitoring group and write pid into it */
453 	ret = create_grp(ctrlgrp, controlgroup, RESCTRL_PATH);
454 	if (ret)
455 		goto out;
456 	sprintf(tasks, "%s/tasks", controlgroup);
457 	ret = write_pid_to_tasks(tasks, bm_pid);
458 	if (ret)
459 		goto out;
460 
461 	/* Create mon grp and write pid into it for "mbm" and "cqm" test */
462 	if (!strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)) ||
463 	    !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
464 		if (strlen(mongrp)) {
465 			sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
466 			sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
467 			ret = create_grp(mongrp, monitorgroup, monitorgroup_p);
468 			if (ret)
469 				goto out;
470 
471 			sprintf(tasks, "%s/mon_groups/%s/tasks",
472 				controlgroup, mongrp);
473 			ret = write_pid_to_tasks(tasks, bm_pid);
474 			if (ret)
475 				goto out;
476 		}
477 	}
478 
479 out:
480 	printf("%sok writing benchmark parameters to resctrl FS\n",
481 	       ret ? "not " : "");
482 	if (ret)
483 		perror("# writing to resctrlfs");
484 
485 	tests_run++;
486 
487 	return ret;
488 }
489 
490 /*
491  * write_schemata - Update schemata of a con_mon grp
492  * @ctrlgrp:		Name of the con_mon grp
493  * @schemata:		Schemata that should be updated to
494  * @cpu_no:		CPU number that the benchmark PID is binded to
495  * @resctrl_val:	Resctrl feature (Eg: mbm, mba.. etc)
496  *
497  * Update schemata of a con_mon grp *only* if requested resctrl feature is
498  * allocation type
499  *
500  * Return: 0 on success, non-zero on failure
501  */
write_schemata(char * ctrlgrp,char * schemata,int cpu_no,char * resctrl_val)502 int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, char *resctrl_val)
503 {
504 	char controlgroup[1024], schema[1024], reason[64];
505 	int resource_id, ret = 0;
506 	FILE *fp;
507 
508 	if (strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) &&
509 	    strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) &&
510 	    strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
511 		return -ENOENT;
512 
513 	if (!schemata) {
514 		printf("# Skipping empty schemata update\n");
515 
516 		return -1;
517 	}
518 
519 	if (get_resource_id(cpu_no, &resource_id) < 0) {
520 		sprintf(reason, "Failed to get resource id");
521 		ret = -1;
522 
523 		goto out;
524 	}
525 
526 	if (strlen(ctrlgrp) != 0)
527 		sprintf(controlgroup, "%s/%s/schemata", RESCTRL_PATH, ctrlgrp);
528 	else
529 		sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);
530 
531 	if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR)) ||
532 	    !strncmp(resctrl_val, CQM_STR, sizeof(CQM_STR)))
533 		sprintf(schema, "%s%d%c%s", "L3:", resource_id, '=', schemata);
534 	if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)))
535 		sprintf(schema, "%s%d%c%s", "MB:", resource_id, '=', schemata);
536 
537 	fp = fopen(controlgroup, "w");
538 	if (!fp) {
539 		sprintf(reason, "Failed to open control group");
540 		ret = -1;
541 
542 		goto out;
543 	}
544 
545 	if (fprintf(fp, "%s\n", schema) < 0) {
546 		sprintf(reason, "Failed to write schemata in control group");
547 		fclose(fp);
548 		ret = -1;
549 
550 		goto out;
551 	}
552 	fclose(fp);
553 
554 out:
555 	printf("%sok Write schema \"%s\" to resctrl FS%s%s\n",
556 	       ret ? "not " : "", schema, ret ? " # " : "",
557 	       ret ? reason : "");
558 	tests_run++;
559 
560 	return ret;
561 }
562 
check_resctrlfs_support(void)563 bool check_resctrlfs_support(void)
564 {
565 	FILE *inf = fopen("/proc/filesystems", "r");
566 	DIR *dp;
567 	char *res;
568 	bool ret = false;
569 
570 	if (!inf)
571 		return false;
572 
573 	res = fgrep(inf, "nodev\tresctrl\n");
574 
575 	if (res) {
576 		ret = true;
577 		free(res);
578 	}
579 
580 	fclose(inf);
581 
582 	printf("%sok kernel supports resctrl filesystem\n", ret ? "" : "not ");
583 	tests_run++;
584 
585 	dp = opendir(RESCTRL_PATH);
586 	printf("%sok resctrl mountpoint \"%s\" exists\n",
587 	       dp ? "" : "not ", RESCTRL_PATH);
588 	if (dp)
589 		closedir(dp);
590 	tests_run++;
591 
592 	printf("# resctrl filesystem %s mounted\n",
593 	       find_resctrl_mount(NULL) ? "not" : "is");
594 
595 	return ret;
596 }
597 
fgrep(FILE * inf,const char * str)598 char *fgrep(FILE *inf, const char *str)
599 {
600 	char line[256];
601 	int slen = strlen(str);
602 
603 	while (!feof(inf)) {
604 		if (!fgets(line, 256, inf))
605 			break;
606 		if (strncmp(line, str, slen))
607 			continue;
608 
609 		return strdup(line);
610 	}
611 
612 	return NULL;
613 }
614 
615 /*
616  * validate_resctrl_feature_request - Check if requested feature is valid.
617  * @resctrl_val:	Requested feature
618  *
619  * Return: 0 on success, non-zero on failure
620  */
validate_resctrl_feature_request(char * resctrl_val)621 bool validate_resctrl_feature_request(char *resctrl_val)
622 {
623 	FILE *inf = fopen("/proc/cpuinfo", "r");
624 	bool found = false;
625 	char *res;
626 
627 	if (!inf)
628 		return false;
629 
630 	res = fgrep(inf, "flags");
631 
632 	if (res) {
633 		char *s = strchr(res, ':');
634 
635 		found = s && !strstr(s, resctrl_val);
636 		free(res);
637 	}
638 	fclose(inf);
639 
640 	return found;
641 }
642 
filter_dmesg(void)643 int filter_dmesg(void)
644 {
645 	char line[1024];
646 	FILE *fp;
647 	int pipefds[2];
648 	pid_t pid;
649 	int ret;
650 
651 	ret = pipe(pipefds);
652 	if (ret) {
653 		perror("pipe");
654 		return ret;
655 	}
656 	pid = fork();
657 	if (pid == 0) {
658 		close(pipefds[0]);
659 		dup2(pipefds[1], STDOUT_FILENO);
660 		execlp("dmesg", "dmesg", NULL);
661 		perror("executing dmesg");
662 		exit(1);
663 	}
664 	close(pipefds[1]);
665 	fp = fdopen(pipefds[0], "r");
666 	if (!fp) {
667 		perror("fdopen(pipe)");
668 		kill(pid, SIGTERM);
669 
670 		return -1;
671 	}
672 
673 	while (fgets(line, 1024, fp)) {
674 		if (strstr(line, "intel_rdt:"))
675 			printf("# dmesg: %s", line);
676 		if (strstr(line, "resctrl:"))
677 			printf("# dmesg: %s", line);
678 	}
679 	fclose(fp);
680 	waitpid(pid, NULL, 0);
681 
682 	return 0;
683 }
684 
validate_bw_report_request(char * bw_report)685 int validate_bw_report_request(char *bw_report)
686 {
687 	if (strcmp(bw_report, "reads") == 0)
688 		return 0;
689 	if (strcmp(bw_report, "writes") == 0)
690 		return 0;
691 	if (strcmp(bw_report, "nt-writes") == 0) {
692 		strcpy(bw_report, "writes");
693 		return 0;
694 	}
695 	if (strcmp(bw_report, "total") == 0)
696 		return 0;
697 
698 	fprintf(stderr, "Requested iMC B/W report type unavailable\n");
699 
700 	return -1;
701 }
702 
perf_event_open(struct perf_event_attr * hw_event,pid_t pid,int cpu,int group_fd,unsigned long flags)703 int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
704 		    int group_fd, unsigned long flags)
705 {
706 	int ret;
707 
708 	ret = syscall(__NR_perf_event_open, hw_event, pid, cpu,
709 		      group_fd, flags);
710 	return ret;
711 }
712 
count_bits(unsigned long n)713 unsigned int count_bits(unsigned long n)
714 {
715 	unsigned int count = 0;
716 
717 	while (n) {
718 		count += n & 1;
719 		n >>= 1;
720 	}
721 
722 	return count;
723 }
724