1 /* SPDX-License-Identifier: GPL-2.0
2  * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
3  */
4 static const char *__doc__ = " XDP RX-queue info extract example\n\n"
5 	"Monitor how many packets per sec (pps) are received\n"
6 	"per NIC RX queue index and which CPU processed the packet\n"
7 	;
8 
9 #include <errno.h>
10 #include <signal.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <stdbool.h>
14 #include <string.h>
15 #include <unistd.h>
16 #include <locale.h>
17 #include <sys/resource.h>
18 #include <getopt.h>
19 #include <net/if.h>
20 #include <time.h>
21 
22 #include <arpa/inet.h>
23 #include <linux/if_link.h>
24 
25 #include <bpf/bpf.h>
26 #include <bpf/libbpf.h>
27 #include "bpf_util.h"
28 
29 static int ifindex = -1;
30 static char ifname_buf[IF_NAMESIZE];
31 static char *ifname;
32 static __u32 prog_id;
33 
34 static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
35 
36 static struct bpf_map *stats_global_map;
37 static struct bpf_map *rx_queue_index_map;
38 
39 /* Exit return codes */
40 #define EXIT_OK		0
41 #define EXIT_FAIL		1
42 #define EXIT_FAIL_OPTION	2
43 #define EXIT_FAIL_XDP		3
44 #define EXIT_FAIL_BPF		4
45 #define EXIT_FAIL_MEM		5
46 
47 static const struct option long_options[] = {
48 	{"help",	no_argument,		NULL, 'h' },
49 	{"dev",		required_argument,	NULL, 'd' },
50 	{"skb-mode",	no_argument,		NULL, 'S' },
51 	{"sec",		required_argument,	NULL, 's' },
52 	{"no-separators", no_argument,		NULL, 'z' },
53 	{"action",	required_argument,	NULL, 'a' },
54 	{"readmem",	no_argument,		NULL, 'r' },
55 	{"swapmac",	no_argument,		NULL, 'm' },
56 	{"force",	no_argument,		NULL, 'F' },
57 	{0, 0, NULL,  0 }
58 };
59 
int_exit(int sig)60 static void int_exit(int sig)
61 {
62 	__u32 curr_prog_id = 0;
63 
64 	if (ifindex > -1) {
65 		if (bpf_get_link_xdp_id(ifindex, &curr_prog_id, xdp_flags)) {
66 			printf("bpf_get_link_xdp_id failed\n");
67 			exit(EXIT_FAIL);
68 		}
69 		if (prog_id == curr_prog_id) {
70 			fprintf(stderr,
71 				"Interrupted: Removing XDP program on ifindex:%d device:%s\n",
72 				ifindex, ifname);
73 			bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
74 		} else if (!curr_prog_id) {
75 			printf("couldn't find a prog id on a given iface\n");
76 		} else {
77 			printf("program on interface changed, not removing\n");
78 		}
79 	}
80 	exit(EXIT_OK);
81 }
82 
83 struct config {
84 	__u32 action;
85 	int ifindex;
86 	__u32 options;
87 };
88 enum cfg_options_flags {
89 	NO_TOUCH = 0x0U,
90 	READ_MEM = 0x1U,
91 	SWAP_MAC = 0x2U,
92 };
93 #define XDP_ACTION_MAX (XDP_TX + 1)
94 #define XDP_ACTION_MAX_STRLEN 11
95 static const char *xdp_action_names[XDP_ACTION_MAX] = {
96 	[XDP_ABORTED]	= "XDP_ABORTED",
97 	[XDP_DROP]	= "XDP_DROP",
98 	[XDP_PASS]	= "XDP_PASS",
99 	[XDP_TX]	= "XDP_TX",
100 };
101 
action2str(int action)102 static const char *action2str(int action)
103 {
104 	if (action < XDP_ACTION_MAX)
105 		return xdp_action_names[action];
106 	return NULL;
107 }
108 
parse_xdp_action(char * action_str)109 static int parse_xdp_action(char *action_str)
110 {
111 	size_t maxlen;
112 	__u64 action = -1;
113 	int i;
114 
115 	for (i = 0; i < XDP_ACTION_MAX; i++) {
116 		maxlen = XDP_ACTION_MAX_STRLEN;
117 		if (strncmp(xdp_action_names[i], action_str, maxlen) == 0) {
118 			action = i;
119 			break;
120 		}
121 	}
122 	return action;
123 }
124 
list_xdp_actions(void)125 static void list_xdp_actions(void)
126 {
127 	int i;
128 
129 	printf("Available XDP --action <options>\n");
130 	for (i = 0; i < XDP_ACTION_MAX; i++)
131 		printf("\t%s\n", xdp_action_names[i]);
132 	printf("\n");
133 }
134 
options2str(enum cfg_options_flags flag)135 static char* options2str(enum cfg_options_flags flag)
136 {
137 	if (flag == NO_TOUCH)
138 		return "no_touch";
139 	if (flag & SWAP_MAC)
140 		return "swapmac";
141 	if (flag & READ_MEM)
142 		return "read";
143 	fprintf(stderr, "ERR: Unknown config option flags");
144 	exit(EXIT_FAIL);
145 }
146 
usage(char * argv[])147 static void usage(char *argv[])
148 {
149 	int i;
150 
151 	printf("\nDOCUMENTATION:\n%s\n", __doc__);
152 	printf(" Usage: %s (options-see-below)\n", argv[0]);
153 	printf(" Listing options:\n");
154 	for (i = 0; long_options[i].name != 0; i++) {
155 		printf(" --%-12s", long_options[i].name);
156 		if (long_options[i].flag != NULL)
157 			printf(" flag (internal value:%d)",
158 				*long_options[i].flag);
159 		else
160 			printf(" short-option: -%c",
161 				long_options[i].val);
162 		printf("\n");
163 	}
164 	printf("\n");
165 	list_xdp_actions();
166 }
167 
168 #define NANOSEC_PER_SEC 1000000000 /* 10^9 */
gettime(void)169 static __u64 gettime(void)
170 {
171 	struct timespec t;
172 	int res;
173 
174 	res = clock_gettime(CLOCK_MONOTONIC, &t);
175 	if (res < 0) {
176 		fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
177 		exit(EXIT_FAIL);
178 	}
179 	return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
180 }
181 
182 /* Common stats data record shared with _kern.c */
183 struct datarec {
184 	__u64 processed;
185 	__u64 issue;
186 };
187 struct record {
188 	__u64 timestamp;
189 	struct datarec total;
190 	struct datarec *cpu;
191 };
192 struct stats_record {
193 	struct record stats;
194 	struct record *rxq;
195 };
196 
alloc_record_per_cpu(void)197 static struct datarec *alloc_record_per_cpu(void)
198 {
199 	unsigned int nr_cpus = bpf_num_possible_cpus();
200 	struct datarec *array;
201 
202 	array = calloc(nr_cpus, sizeof(struct datarec));
203 	if (!array) {
204 		fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
205 		exit(EXIT_FAIL_MEM);
206 	}
207 	return array;
208 }
209 
alloc_record_per_rxq(void)210 static struct record *alloc_record_per_rxq(void)
211 {
212 	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
213 	struct record *array;
214 
215 	array = calloc(nr_rxqs, sizeof(struct record));
216 	if (!array) {
217 		fprintf(stderr, "Mem alloc error (nr_rxqs:%u)\n", nr_rxqs);
218 		exit(EXIT_FAIL_MEM);
219 	}
220 	return array;
221 }
222 
alloc_stats_record(void)223 static struct stats_record *alloc_stats_record(void)
224 {
225 	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
226 	struct stats_record *rec;
227 	int i;
228 
229 	rec = calloc(1, sizeof(struct stats_record));
230 	if (!rec) {
231 		fprintf(stderr, "Mem alloc error\n");
232 		exit(EXIT_FAIL_MEM);
233 	}
234 	rec->rxq = alloc_record_per_rxq();
235 	for (i = 0; i < nr_rxqs; i++)
236 		rec->rxq[i].cpu = alloc_record_per_cpu();
237 
238 	rec->stats.cpu = alloc_record_per_cpu();
239 	return rec;
240 }
241 
free_stats_record(struct stats_record * r)242 static void free_stats_record(struct stats_record *r)
243 {
244 	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
245 	int i;
246 
247 	for (i = 0; i < nr_rxqs; i++)
248 		free(r->rxq[i].cpu);
249 
250 	free(r->rxq);
251 	free(r->stats.cpu);
252 	free(r);
253 }
254 
map_collect_percpu(int fd,__u32 key,struct record * rec)255 static bool map_collect_percpu(int fd, __u32 key, struct record *rec)
256 {
257 	/* For percpu maps, userspace gets a value per possible CPU */
258 	unsigned int nr_cpus = bpf_num_possible_cpus();
259 	struct datarec values[nr_cpus];
260 	__u64 sum_processed = 0;
261 	__u64 sum_issue = 0;
262 	int i;
263 
264 	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
265 		fprintf(stderr,
266 			"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
267 		return false;
268 	}
269 	/* Get time as close as possible to reading map contents */
270 	rec->timestamp = gettime();
271 
272 	/* Record and sum values from each CPU */
273 	for (i = 0; i < nr_cpus; i++) {
274 		rec->cpu[i].processed = values[i].processed;
275 		sum_processed        += values[i].processed;
276 		rec->cpu[i].issue = values[i].issue;
277 		sum_issue        += values[i].issue;
278 	}
279 	rec->total.processed = sum_processed;
280 	rec->total.issue     = sum_issue;
281 	return true;
282 }
283 
stats_collect(struct stats_record * rec)284 static void stats_collect(struct stats_record *rec)
285 {
286 	int fd, i, max_rxqs;
287 
288 	fd = bpf_map__fd(stats_global_map);
289 	map_collect_percpu(fd, 0, &rec->stats);
290 
291 	fd = bpf_map__fd(rx_queue_index_map);
292 	max_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
293 	for (i = 0; i < max_rxqs; i++)
294 		map_collect_percpu(fd, i, &rec->rxq[i]);
295 }
296 
calc_period(struct record * r,struct record * p)297 static double calc_period(struct record *r, struct record *p)
298 {
299 	double period_ = 0;
300 	__u64 period = 0;
301 
302 	period = r->timestamp - p->timestamp;
303 	if (period > 0)
304 		period_ = ((double) period / NANOSEC_PER_SEC);
305 
306 	return period_;
307 }
308 
calc_pps(struct datarec * r,struct datarec * p,double period_)309 static __u64 calc_pps(struct datarec *r, struct datarec *p, double period_)
310 {
311 	__u64 packets = 0;
312 	__u64 pps = 0;
313 
314 	if (period_ > 0) {
315 		packets = r->processed - p->processed;
316 		pps = packets / period_;
317 	}
318 	return pps;
319 }
320 
calc_errs_pps(struct datarec * r,struct datarec * p,double period_)321 static __u64 calc_errs_pps(struct datarec *r,
322 			    struct datarec *p, double period_)
323 {
324 	__u64 packets = 0;
325 	__u64 pps = 0;
326 
327 	if (period_ > 0) {
328 		packets = r->issue - p->issue;
329 		pps = packets / period_;
330 	}
331 	return pps;
332 }
333 
stats_print(struct stats_record * stats_rec,struct stats_record * stats_prev,int action,__u32 cfg_opt)334 static void stats_print(struct stats_record *stats_rec,
335 			struct stats_record *stats_prev,
336 			int action, __u32 cfg_opt)
337 {
338 	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
339 	unsigned int nr_cpus = bpf_num_possible_cpus();
340 	double pps = 0, err = 0;
341 	struct record *rec, *prev;
342 	double t;
343 	int rxq;
344 	int i;
345 
346 	/* Header */
347 	printf("\nRunning XDP on dev:%s (ifindex:%d) action:%s options:%s\n",
348 	       ifname, ifindex, action2str(action), options2str(cfg_opt));
349 
350 	/* stats_global_map */
351 	{
352 		char *fmt_rx = "%-15s %-7d %'-11.0f %'-10.0f %s\n";
353 		char *fm2_rx = "%-15s %-7s %'-11.0f\n";
354 		char *errstr = "";
355 
356 		printf("%-15s %-7s %-11s %-11s\n",
357 		       "XDP stats", "CPU", "pps", "issue-pps");
358 
359 		rec  =  &stats_rec->stats;
360 		prev = &stats_prev->stats;
361 		t = calc_period(rec, prev);
362 		for (i = 0; i < nr_cpus; i++) {
363 			struct datarec *r = &rec->cpu[i];
364 			struct datarec *p = &prev->cpu[i];
365 
366 			pps = calc_pps     (r, p, t);
367 			err = calc_errs_pps(r, p, t);
368 			if (err > 0)
369 				errstr = "invalid-ifindex";
370 			if (pps > 0)
371 				printf(fmt_rx, "XDP-RX CPU",
372 					i, pps, err, errstr);
373 		}
374 		pps  = calc_pps     (&rec->total, &prev->total, t);
375 		err  = calc_errs_pps(&rec->total, &prev->total, t);
376 		printf(fm2_rx, "XDP-RX CPU", "total", pps, err);
377 	}
378 
379 	/* rx_queue_index_map */
380 	printf("\n%-15s %-7s %-11s %-11s\n",
381 	       "RXQ stats", "RXQ:CPU", "pps", "issue-pps");
382 
383 	for (rxq = 0; rxq < nr_rxqs; rxq++) {
384 		char *fmt_rx = "%-15s %3d:%-3d %'-11.0f %'-10.0f %s\n";
385 		char *fm2_rx = "%-15s %3d:%-3s %'-11.0f\n";
386 		char *errstr = "";
387 		int rxq_ = rxq;
388 
389 		/* Last RXQ in map catch overflows */
390 		if (rxq_ == nr_rxqs - 1)
391 			rxq_ = -1;
392 
393 		rec  =  &stats_rec->rxq[rxq];
394 		prev = &stats_prev->rxq[rxq];
395 		t = calc_period(rec, prev);
396 		for (i = 0; i < nr_cpus; i++) {
397 			struct datarec *r = &rec->cpu[i];
398 			struct datarec *p = &prev->cpu[i];
399 
400 			pps = calc_pps     (r, p, t);
401 			err = calc_errs_pps(r, p, t);
402 			if (err > 0) {
403 				if (rxq_ == -1)
404 					errstr = "map-overflow-RXQ";
405 				else
406 					errstr = "err";
407 			}
408 			if (pps > 0)
409 				printf(fmt_rx, "rx_queue_index",
410 				       rxq_, i, pps, err, errstr);
411 		}
412 		pps  = calc_pps     (&rec->total, &prev->total, t);
413 		err  = calc_errs_pps(&rec->total, &prev->total, t);
414 		if (pps || err)
415 			printf(fm2_rx, "rx_queue_index", rxq_, "sum", pps, err);
416 	}
417 }
418 
419 
420 /* Pointer swap trick */
swap(struct stats_record ** a,struct stats_record ** b)421 static inline void swap(struct stats_record **a, struct stats_record **b)
422 {
423 	struct stats_record *tmp;
424 
425 	tmp = *a;
426 	*a = *b;
427 	*b = tmp;
428 }
429 
stats_poll(int interval,int action,__u32 cfg_opt)430 static void stats_poll(int interval, int action, __u32 cfg_opt)
431 {
432 	struct stats_record *record, *prev;
433 
434 	record = alloc_stats_record();
435 	prev   = alloc_stats_record();
436 	stats_collect(record);
437 
438 	while (1) {
439 		swap(&prev, &record);
440 		stats_collect(record);
441 		stats_print(record, prev, action, cfg_opt);
442 		sleep(interval);
443 	}
444 
445 	free_stats_record(record);
446 	free_stats_record(prev);
447 }
448 
449 
main(int argc,char ** argv)450 int main(int argc, char **argv)
451 {
452 	__u32 cfg_options= NO_TOUCH ; /* Default: Don't touch packet memory */
453 	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
454 	struct bpf_prog_load_attr prog_load_attr = {
455 		.prog_type	= BPF_PROG_TYPE_XDP,
456 	};
457 	struct bpf_prog_info info = {};
458 	__u32 info_len = sizeof(info);
459 	int prog_fd, map_fd, opt, err;
460 	bool use_separators = true;
461 	struct config cfg = { 0 };
462 	struct bpf_object *obj;
463 	struct bpf_map *map;
464 	char filename[256];
465 	int longindex = 0;
466 	int interval = 2;
467 	__u32 key = 0;
468 
469 
470 	char action_str_buf[XDP_ACTION_MAX_STRLEN + 1 /* for \0 */] = { 0 };
471 	int action = XDP_PASS; /* Default action */
472 	char *action_str = NULL;
473 
474 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
475 	prog_load_attr.file = filename;
476 
477 	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
478 		perror("setrlimit(RLIMIT_MEMLOCK)");
479 		return 1;
480 	}
481 
482 	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
483 		return EXIT_FAIL;
484 
485 	map =  bpf_object__find_map_by_name(obj, "config_map");
486 	stats_global_map = bpf_object__find_map_by_name(obj, "stats_global_map");
487 	rx_queue_index_map = bpf_object__find_map_by_name(obj, "rx_queue_index_map");
488 	if (!map || !stats_global_map || !rx_queue_index_map) {
489 		printf("finding a map in obj file failed\n");
490 		return EXIT_FAIL;
491 	}
492 	map_fd = bpf_map__fd(map);
493 
494 	if (!prog_fd) {
495 		fprintf(stderr, "ERR: bpf_prog_load_xattr: %s\n", strerror(errno));
496 		return EXIT_FAIL;
497 	}
498 
499 	/* Parse commands line args */
500 	while ((opt = getopt_long(argc, argv, "FhSrmzd:s:a:",
501 				  long_options, &longindex)) != -1) {
502 		switch (opt) {
503 		case 'd':
504 			if (strlen(optarg) >= IF_NAMESIZE) {
505 				fprintf(stderr, "ERR: --dev name too long\n");
506 				goto error;
507 			}
508 			ifname = (char *)&ifname_buf;
509 			strncpy(ifname, optarg, IF_NAMESIZE);
510 			ifindex = if_nametoindex(ifname);
511 			if (ifindex == 0) {
512 				fprintf(stderr,
513 					"ERR: --dev name unknown err(%d):%s\n",
514 					errno, strerror(errno));
515 				goto error;
516 			}
517 			break;
518 		case 's':
519 			interval = atoi(optarg);
520 			break;
521 		case 'S':
522 			xdp_flags |= XDP_FLAGS_SKB_MODE;
523 			break;
524 		case 'z':
525 			use_separators = false;
526 			break;
527 		case 'a':
528 			action_str = (char *)&action_str_buf;
529 			strncpy(action_str, optarg, XDP_ACTION_MAX_STRLEN);
530 			break;
531 		case 'r':
532 			cfg_options |= READ_MEM;
533 			break;
534 		case 'm':
535 			cfg_options |= SWAP_MAC;
536 			break;
537 		case 'F':
538 			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
539 			break;
540 		case 'h':
541 		error:
542 		default:
543 			usage(argv);
544 			return EXIT_FAIL_OPTION;
545 		}
546 	}
547 
548 	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
549 		xdp_flags |= XDP_FLAGS_DRV_MODE;
550 
551 	/* Required option */
552 	if (ifindex == -1) {
553 		fprintf(stderr, "ERR: required option --dev missing\n");
554 		usage(argv);
555 		return EXIT_FAIL_OPTION;
556 	}
557 	cfg.ifindex = ifindex;
558 
559 	/* Parse action string */
560 	if (action_str) {
561 		action = parse_xdp_action(action_str);
562 		if (action < 0) {
563 			fprintf(stderr, "ERR: Invalid XDP --action: %s\n",
564 				action_str);
565 			list_xdp_actions();
566 			return EXIT_FAIL_OPTION;
567 		}
568 	}
569 	cfg.action = action;
570 
571 	/* XDP_TX requires changing MAC-addrs, else HW may drop */
572 	if (action == XDP_TX)
573 		cfg_options |= SWAP_MAC;
574 	cfg.options = cfg_options;
575 
576 	/* Trick to pretty printf with thousands separators use %' */
577 	if (use_separators)
578 		setlocale(LC_NUMERIC, "en_US");
579 
580 	/* User-side setup ifindex in config_map */
581 	err = bpf_map_update_elem(map_fd, &key, &cfg, 0);
582 	if (err) {
583 		fprintf(stderr, "Store config failed (err:%d)\n", err);
584 		exit(EXIT_FAIL_BPF);
585 	}
586 
587 	/* Remove XDP program when program is interrupted or killed */
588 	signal(SIGINT, int_exit);
589 	signal(SIGTERM, int_exit);
590 
591 	if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
592 		fprintf(stderr, "link set xdp fd failed\n");
593 		return EXIT_FAIL_XDP;
594 	}
595 
596 	err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
597 	if (err) {
598 		printf("can't get prog info - %s\n", strerror(errno));
599 		return err;
600 	}
601 	prog_id = info.id;
602 
603 	stats_poll(interval, action, cfg_options);
604 	return EXIT_OK;
605 }
606