1/* SPDX-License-Identifier: GPL-2.0
  2 * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
  3 */
  4static 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.h"
 26#include "libbpf.h"
 27#include "bpf_util.h"
 28
 29static int ifindex = -1;
 30static char ifname_buf[IF_NAMESIZE];
 31static char *ifname;
 32static __u32 prog_id;
 33
 34static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
 35
 36static struct bpf_map *stats_global_map;
 37static 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
 47static 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
 60static 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
 83struct config {
 84	__u32 action;
 85	int ifindex;
 86	__u32 options;
 87};
 88enum 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
 95static 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
102static const char *action2str(int action)
103{
104	if (action < XDP_ACTION_MAX)
105		return xdp_action_names[action];
106	return NULL;
107}
108
109static 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
125static 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
135static 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
147static 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 */
169static __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 */
183struct datarec {
184	__u64 processed;
185	__u64 issue;
186};
187struct record {
188	__u64 timestamp;
189	struct datarec total;
190	struct datarec *cpu;
191};
192struct stats_record {
193	struct record stats;
194	struct record *rxq;
195};
196
197static struct datarec *alloc_record_per_cpu(void)
198{
199	unsigned int nr_cpus = bpf_num_possible_cpus();
200	struct datarec *array;
201	size_t size;
202
203	size = sizeof(struct datarec) * nr_cpus;
204	array = malloc(size);
205	memset(array, 0, size);
206	if (!array) {
207		fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
208		exit(EXIT_FAIL_MEM);
209	}
210	return array;
211}
212
213static struct record *alloc_record_per_rxq(void)
214{
215	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
216	struct record *array;
217	size_t size;
218
219	size = sizeof(struct record) * nr_rxqs;
220	array = malloc(size);
221	memset(array, 0, size);
222	if (!array) {
223		fprintf(stderr, "Mem alloc error (nr_rxqs:%u)\n", nr_rxqs);
224		exit(EXIT_FAIL_MEM);
225	}
226	return array;
227}
228
229static struct stats_record *alloc_stats_record(void)
230{
231	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
232	struct stats_record *rec;
233	int i;
234
235	rec = malloc(sizeof(*rec));
236	memset(rec, 0, sizeof(*rec));
237	if (!rec) {
238		fprintf(stderr, "Mem alloc error\n");
239		exit(EXIT_FAIL_MEM);
240	}
241	rec->rxq = alloc_record_per_rxq();
242	for (i = 0; i < nr_rxqs; i++)
243		rec->rxq[i].cpu = alloc_record_per_cpu();
244
245	rec->stats.cpu = alloc_record_per_cpu();
246	return rec;
247}
248
249static void free_stats_record(struct stats_record *r)
250{
251	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
252	int i;
253
254	for (i = 0; i < nr_rxqs; i++)
255		free(r->rxq[i].cpu);
256
257	free(r->rxq);
258	free(r->stats.cpu);
259	free(r);
260}
261
262static bool map_collect_percpu(int fd, __u32 key, struct record *rec)
263{
264	/* For percpu maps, userspace gets a value per possible CPU */
265	unsigned int nr_cpus = bpf_num_possible_cpus();
266	struct datarec values[nr_cpus];
267	__u64 sum_processed = 0;
268	__u64 sum_issue = 0;
269	int i;
270
271	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
272		fprintf(stderr,
273			"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
274		return false;
275	}
276	/* Get time as close as possible to reading map contents */
277	rec->timestamp = gettime();
278
279	/* Record and sum values from each CPU */
280	for (i = 0; i < nr_cpus; i++) {
281		rec->cpu[i].processed = values[i].processed;
282		sum_processed        += values[i].processed;
283		rec->cpu[i].issue = values[i].issue;
284		sum_issue        += values[i].issue;
285	}
286	rec->total.processed = sum_processed;
287	rec->total.issue     = sum_issue;
288	return true;
289}
290
291static void stats_collect(struct stats_record *rec)
292{
293	int fd, i, max_rxqs;
294
295	fd = bpf_map__fd(stats_global_map);
296	map_collect_percpu(fd, 0, &rec->stats);
297
298	fd = bpf_map__fd(rx_queue_index_map);
299	max_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
300	for (i = 0; i < max_rxqs; i++)
301		map_collect_percpu(fd, i, &rec->rxq[i]);
302}
303
304static double calc_period(struct record *r, struct record *p)
305{
306	double period_ = 0;
307	__u64 period = 0;
308
309	period = r->timestamp - p->timestamp;
310	if (period > 0)
311		period_ = ((double) period / NANOSEC_PER_SEC);
312
313	return period_;
314}
315
316static __u64 calc_pps(struct datarec *r, struct datarec *p, double period_)
317{
318	__u64 packets = 0;
319	__u64 pps = 0;
320
321	if (period_ > 0) {
322		packets = r->processed - p->processed;
323		pps = packets / period_;
324	}
325	return pps;
326}
327
328static __u64 calc_errs_pps(struct datarec *r,
329			    struct datarec *p, double period_)
330{
331	__u64 packets = 0;
332	__u64 pps = 0;
333
334	if (period_ > 0) {
335		packets = r->issue - p->issue;
336		pps = packets / period_;
337	}
338	return pps;
339}
340
341static void stats_print(struct stats_record *stats_rec,
342			struct stats_record *stats_prev,
343			int action, __u32 cfg_opt)
344{
345	unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
346	unsigned int nr_cpus = bpf_num_possible_cpus();
347	double pps = 0, err = 0;
348	struct record *rec, *prev;
349	double t;
350	int rxq;
351	int i;
352
353	/* Header */
354	printf("\nRunning XDP on dev:%s (ifindex:%d) action:%s options:%s\n",
355	       ifname, ifindex, action2str(action), options2str(cfg_opt));
356
357	/* stats_global_map */
358	{
359		char *fmt_rx = "%-15s %-7d %'-11.0f %'-10.0f %s\n";
360		char *fm2_rx = "%-15s %-7s %'-11.0f\n";
361		char *errstr = "";
362
363		printf("%-15s %-7s %-11s %-11s\n",
364		       "XDP stats", "CPU", "pps", "issue-pps");
365
366		rec  =  &stats_rec->stats;
367		prev = &stats_prev->stats;
368		t = calc_period(rec, prev);
369		for (i = 0; i < nr_cpus; i++) {
370			struct datarec *r = &rec->cpu[i];
371			struct datarec *p = &prev->cpu[i];
372
373			pps = calc_pps     (r, p, t);
374			err = calc_errs_pps(r, p, t);
375			if (err > 0)
376				errstr = "invalid-ifindex";
377			if (pps > 0)
378				printf(fmt_rx, "XDP-RX CPU",
379					i, pps, err, errstr);
380		}
381		pps  = calc_pps     (&rec->total, &prev->total, t);
382		err  = calc_errs_pps(&rec->total, &prev->total, t);
383		printf(fm2_rx, "XDP-RX CPU", "total", pps, err);
384	}
385
386	/* rx_queue_index_map */
387	printf("\n%-15s %-7s %-11s %-11s\n",
388	       "RXQ stats", "RXQ:CPU", "pps", "issue-pps");
389
390	for (rxq = 0; rxq < nr_rxqs; rxq++) {
391		char *fmt_rx = "%-15s %3d:%-3d %'-11.0f %'-10.0f %s\n";
392		char *fm2_rx = "%-15s %3d:%-3s %'-11.0f\n";
393		char *errstr = "";
394		int rxq_ = rxq;
395
396		/* Last RXQ in map catch overflows */
397		if (rxq_ == nr_rxqs - 1)
398			rxq_ = -1;
399
400		rec  =  &stats_rec->rxq[rxq];
401		prev = &stats_prev->rxq[rxq];
402		t = calc_period(rec, prev);
403		for (i = 0; i < nr_cpus; i++) {
404			struct datarec *r = &rec->cpu[i];
405			struct datarec *p = &prev->cpu[i];
406
407			pps = calc_pps     (r, p, t);
408			err = calc_errs_pps(r, p, t);
409			if (err > 0) {
410				if (rxq_ == -1)
411					errstr = "map-overflow-RXQ";
412				else
413					errstr = "err";
414			}
415			if (pps > 0)
416				printf(fmt_rx, "rx_queue_index",
417				       rxq_, i, pps, err, errstr);
418		}
419		pps  = calc_pps     (&rec->total, &prev->total, t);
420		err  = calc_errs_pps(&rec->total, &prev->total, t);
421		if (pps || err)
422			printf(fm2_rx, "rx_queue_index", rxq_, "sum", pps, err);
423	}
424}
425
426
427/* Pointer swap trick */
428static inline void swap(struct stats_record **a, struct stats_record **b)
429{
430	struct stats_record *tmp;
431
432	tmp = *a;
433	*a = *b;
434	*b = tmp;
435}
436
437static void stats_poll(int interval, int action, __u32 cfg_opt)
438{
439	struct stats_record *record, *prev;
440
441	record = alloc_stats_record();
442	prev   = alloc_stats_record();
443	stats_collect(record);
444
445	while (1) {
446		swap(&prev, &record);
447		stats_collect(record);
448		stats_print(record, prev, action, cfg_opt);
449		sleep(interval);
450	}
451
452	free_stats_record(record);
453	free_stats_record(prev);
454}
455
456
457int main(int argc, char **argv)
458{
459	__u32 cfg_options= NO_TOUCH ; /* Default: Don't touch packet memory */
460	struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
461	struct bpf_prog_load_attr prog_load_attr = {
462		.prog_type	= BPF_PROG_TYPE_XDP,
463	};
464	struct bpf_prog_info info = {};
465	__u32 info_len = sizeof(info);
466	int prog_fd, map_fd, opt, err;
467	bool use_separators = true;
468	struct config cfg = { 0 };
469	struct bpf_object *obj;
470	struct bpf_map *map;
471	char filename[256];
472	int longindex = 0;
473	int interval = 2;
474	__u32 key = 0;
475
476
477	char action_str_buf[XDP_ACTION_MAX_STRLEN + 1 /* for \0 */] = { 0 };
478	int action = XDP_PASS; /* Default action */
479	char *action_str = NULL;
480
481	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
482	prog_load_attr.file = filename;
483
484	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
485		perror("setrlimit(RLIMIT_MEMLOCK)");
486		return 1;
487	}
488
489	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
490		return EXIT_FAIL;
491
492	map = bpf_map__next(NULL, obj);
493	stats_global_map = bpf_map__next(map, obj);
494	rx_queue_index_map = bpf_map__next(stats_global_map, obj);
495	if (!map || !stats_global_map || !rx_queue_index_map) {
496		printf("finding a map in obj file failed\n");
497		return EXIT_FAIL;
498	}
499	map_fd = bpf_map__fd(map);
500
501	if (!prog_fd) {
502		fprintf(stderr, "ERR: load_bpf_file: %s\n", strerror(errno));
503		return EXIT_FAIL;
504	}
505
506	/* Parse commands line args */
507	while ((opt = getopt_long(argc, argv, "FhSrmzd:s:a:",
508				  long_options, &longindex)) != -1) {
509		switch (opt) {
510		case 'd':
511			if (strlen(optarg) >= IF_NAMESIZE) {
512				fprintf(stderr, "ERR: --dev name too long\n");
513				goto error;
514			}
515			ifname = (char *)&ifname_buf;
516			strncpy(ifname, optarg, IF_NAMESIZE);
517			ifindex = if_nametoindex(ifname);
518			if (ifindex == 0) {
519				fprintf(stderr,
520					"ERR: --dev name unknown err(%d):%s\n",
521					errno, strerror(errno));
522				goto error;
523			}
524			break;
525		case 's':
526			interval = atoi(optarg);
527			break;
528		case 'S':
529			xdp_flags |= XDP_FLAGS_SKB_MODE;
530			break;
531		case 'z':
532			use_separators = false;
533			break;
534		case 'a':
535			action_str = (char *)&action_str_buf;
536			strncpy(action_str, optarg, XDP_ACTION_MAX_STRLEN);
537			break;
538		case 'r':
539			cfg_options |= READ_MEM;
540			break;
541		case 'm':
542			cfg_options |= SWAP_MAC;
543			break;
544		case 'F':
545			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
546			break;
547		case 'h':
548		error:
549		default:
550			usage(argv);
551			return EXIT_FAIL_OPTION;
552		}
553	}
554	/* Required option */
555	if (ifindex == -1) {
556		fprintf(stderr, "ERR: required option --dev missing\n");
557		usage(argv);
558		return EXIT_FAIL_OPTION;
559	}
560	cfg.ifindex = ifindex;
561
562	/* Parse action string */
563	if (action_str) {
564		action = parse_xdp_action(action_str);
565		if (action < 0) {
566			fprintf(stderr, "ERR: Invalid XDP --action: %s\n",
567				action_str);
568			list_xdp_actions();
569			return EXIT_FAIL_OPTION;
570		}
571	}
572	cfg.action = action;
573
574	/* XDP_TX requires changing MAC-addrs, else HW may drop */
575	if (action == XDP_TX)
576		cfg_options |= SWAP_MAC;
577	cfg.options = cfg_options;
578
579	/* Trick to pretty printf with thousands separators use %' */
580	if (use_separators)
581		setlocale(LC_NUMERIC, "en_US");
582
583	/* User-side setup ifindex in config_map */
584	err = bpf_map_update_elem(map_fd, &key, &cfg, 0);
585	if (err) {
586		fprintf(stderr, "Store config failed (err:%d)\n", err);
587		exit(EXIT_FAIL_BPF);
588	}
589
590	/* Remove XDP program when program is interrupted or killed */
591	signal(SIGINT, int_exit);
592	signal(SIGTERM, int_exit);
593
594	if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
595		fprintf(stderr, "link set xdp fd failed\n");
596		return EXIT_FAIL_XDP;
597	}
598
599	err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
600	if (err) {
601		printf("can't get prog info - %s\n", strerror(errno));
602		return err;
603	}
604	prog_id = info.id;
605
606	stats_poll(interval, action, cfg_options);
607	return EXIT_OK;
608}