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  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 <getopt.h>
 18#include <net/if.h>
 19#include <time.h>
 20#include <limits.h>
 21#include <arpa/inet.h>
 22#include <linux/if_link.h>
 23
 24#include <bpf/bpf.h>
 25#include <bpf/libbpf.h>
 26#include "bpf_util.h"
 27
 28static int ifindex = -1;
 29static char ifname_buf[IF_NAMESIZE];
 30static char *ifname;
 31static __u32 prog_id;
 32
 33static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
 34
 35static struct bpf_map *stats_global_map;
 36static struct bpf_map *rx_queue_index_map;
 37
 38/* Exit return codes */
 39#define EXIT_OK		0
 40#define EXIT_FAIL		1
 41#define EXIT_FAIL_OPTION	2
 42#define EXIT_FAIL_XDP		3
 43#define EXIT_FAIL_BPF		4
 44#define EXIT_FAIL_MEM		5
 45
 46#define FAIL_MEM_SIG		INT_MAX
 47#define FAIL_STAT_SIG		(INT_MAX - 1)
 48
 49static const struct option long_options[] = {
 50	{"help",	no_argument,		NULL, 'h' },
 51	{"dev",		required_argument,	NULL, 'd' },
 52	{"skb-mode",	no_argument,		NULL, 'S' },
 53	{"sec",		required_argument,	NULL, 's' },
 54	{"no-separators", no_argument,		NULL, 'z' },
 55	{"action",	required_argument,	NULL, 'a' },
 56	{"readmem",	no_argument,		NULL, 'r' },
 57	{"swapmac",	no_argument,		NULL, 'm' },
 58	{"force",	no_argument,		NULL, 'F' },
 59	{0, 0, NULL,  0 }
 60};
 61
 62static void int_exit(int sig)
 63{
 64	__u32 curr_prog_id = 0;
 65
 66	if (ifindex > -1) {
 67		if (bpf_xdp_query_id(ifindex, xdp_flags, &curr_prog_id)) {
 68			printf("bpf_xdp_query_id failed\n");
 69			exit(EXIT_FAIL);
 70		}
 71		if (prog_id == curr_prog_id) {
 72			fprintf(stderr,
 73				"Interrupted: Removing XDP program on ifindex:%d device:%s\n",
 74				ifindex, ifname);
 75			bpf_xdp_detach(ifindex, xdp_flags, NULL);
 76		} else if (!curr_prog_id) {
 77			printf("couldn't find a prog id on a given iface\n");
 78		} else {
 79			printf("program on interface changed, not removing\n");
 80		}
 81	}
 82
 83	if (sig == FAIL_MEM_SIG)
 84		exit(EXIT_FAIL_MEM);
 85	else if (sig == FAIL_STAT_SIG)
 86		exit(EXIT_FAIL);
 87
 88	exit(EXIT_OK);
 89}
 90
 91struct config {
 92	__u32 action;
 93	int ifindex;
 94	__u32 options;
 95};
 96enum cfg_options_flags {
 97	NO_TOUCH = 0x0U,
 98	READ_MEM = 0x1U,
 99	SWAP_MAC = 0x2U,
100};
101#define XDP_ACTION_MAX (XDP_TX + 1)
102#define XDP_ACTION_MAX_STRLEN 11
103static const char *xdp_action_names[XDP_ACTION_MAX] = {
104	[XDP_ABORTED]	= "XDP_ABORTED",
105	[XDP_DROP]	= "XDP_DROP",
106	[XDP_PASS]	= "XDP_PASS",
107	[XDP_TX]	= "XDP_TX",
108};
109
110static const char *action2str(int action)
111{
112	if (action < XDP_ACTION_MAX)
113		return xdp_action_names[action];
114	return NULL;
115}
116
117static int parse_xdp_action(char *action_str)
118{
119	size_t maxlen;
120	__u64 action = -1;
121	int i;
122
123	for (i = 0; i < XDP_ACTION_MAX; i++) {
124		maxlen = XDP_ACTION_MAX_STRLEN;
125		if (strncmp(xdp_action_names[i], action_str, maxlen) == 0) {
126			action = i;
127			break;
128		}
129	}
130	return action;
131}
132
133static void list_xdp_actions(void)
134{
135	int i;
136
137	printf("Available XDP --action <options>\n");
138	for (i = 0; i < XDP_ACTION_MAX; i++)
139		printf("\t%s\n", xdp_action_names[i]);
140	printf("\n");
141}
142
143static char* options2str(enum cfg_options_flags flag)
144{
145	if (flag == NO_TOUCH)
146		return "no_touch";
147	if (flag & SWAP_MAC)
148		return "swapmac";
149	if (flag & READ_MEM)
150		return "read";
151	fprintf(stderr, "ERR: Unknown config option flags");
152	int_exit(FAIL_STAT_SIG);
153	return "unknown";
154}
155
156static void usage(char *argv[])
157{
158	int i;
159
160	printf("\nDOCUMENTATION:\n%s\n", __doc__);
161	printf(" Usage: %s (options-see-below)\n", argv[0]);
162	printf(" Listing options:\n");
163	for (i = 0; long_options[i].name != 0; i++) {
164		printf(" --%-12s", long_options[i].name);
165		if (long_options[i].flag != NULL)
166			printf(" flag (internal value:%d)",
167				*long_options[i].flag);
168		else
169			printf(" short-option: -%c",
170				long_options[i].val);
171		printf("\n");
172	}
173	printf("\n");
174	list_xdp_actions();
175}
176
177#define NANOSEC_PER_SEC 1000000000 /* 10^9 */
178static __u64 gettime(void)
179{
180	struct timespec t;
181	int res;
182
183	res = clock_gettime(CLOCK_MONOTONIC, &t);
184	if (res < 0) {
185		fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
186		int_exit(FAIL_STAT_SIG);
187	}
188	return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
189}
190
191/* Common stats data record shared with _kern.c */
192struct datarec {
193	__u64 processed;
194	__u64 issue;
195};
196struct record {
197	__u64 timestamp;
198	struct datarec total;
199	struct datarec *cpu;
200};
201struct stats_record {
202	struct record stats;
203	struct record *rxq;
204};
205
206static struct datarec *alloc_record_per_cpu(void)
207{
208	unsigned int nr_cpus = bpf_num_possible_cpus();
209	struct datarec *array;
210
211	array = calloc(nr_cpus, sizeof(struct datarec));
212	if (!array) {
213		fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
214		int_exit(FAIL_MEM_SIG);
215	}
216	return array;
217}
218
219static struct record *alloc_record_per_rxq(void)
220{
221	unsigned int nr_rxqs = bpf_map__max_entries(rx_queue_index_map);
222	struct record *array;
223
224	array = calloc(nr_rxqs, sizeof(struct record));
225	if (!array) {
226		fprintf(stderr, "Mem alloc error (nr_rxqs:%u)\n", nr_rxqs);
227		int_exit(FAIL_MEM_SIG);
228	}
229	return array;
230}
231
232static struct stats_record *alloc_stats_record(void)
233{
234	unsigned int nr_rxqs = bpf_map__max_entries(rx_queue_index_map);
235	struct stats_record *rec;
236	int i;
237
238	rec = calloc(1, sizeof(struct stats_record));
239	if (!rec) {
240		fprintf(stderr, "Mem alloc error\n");
241		int_exit(FAIL_MEM_SIG);
242	}
243	rec->rxq = alloc_record_per_rxq();
244	for (i = 0; i < nr_rxqs; i++)
245		rec->rxq[i].cpu = alloc_record_per_cpu();
246
247	rec->stats.cpu = alloc_record_per_cpu();
248	return rec;
249}
250
251static void free_stats_record(struct stats_record *r)
252{
253	unsigned int nr_rxqs = bpf_map__max_entries(rx_queue_index_map);
254	int i;
255
256	for (i = 0; i < nr_rxqs; i++)
257		free(r->rxq[i].cpu);
258
259	free(r->rxq);
260	free(r->stats.cpu);
261	free(r);
262}
263
264static bool map_collect_percpu(int fd, __u32 key, struct record *rec)
265{
266	/* For percpu maps, userspace gets a value per possible CPU */
267	unsigned int nr_cpus = bpf_num_possible_cpus();
268	struct datarec values[nr_cpus];
269	__u64 sum_processed = 0;
270	__u64 sum_issue = 0;
271	int i;
272
273	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
274		fprintf(stderr,
275			"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
276		return false;
277	}
278	/* Get time as close as possible to reading map contents */
279	rec->timestamp = gettime();
280
281	/* Record and sum values from each CPU */
282	for (i = 0; i < nr_cpus; i++) {
283		rec->cpu[i].processed = values[i].processed;
284		sum_processed        += values[i].processed;
285		rec->cpu[i].issue = values[i].issue;
286		sum_issue        += values[i].issue;
287	}
288	rec->total.processed = sum_processed;
289	rec->total.issue     = sum_issue;
290	return true;
291}
292
293static void stats_collect(struct stats_record *rec)
294{
295	int fd, i, max_rxqs;
296
297	fd = bpf_map__fd(stats_global_map);
298	map_collect_percpu(fd, 0, &rec->stats);
299
300	fd = bpf_map__fd(rx_queue_index_map);
301	max_rxqs = bpf_map__max_entries(rx_queue_index_map);
302	for (i = 0; i < max_rxqs; i++)
303		map_collect_percpu(fd, i, &rec->rxq[i]);
304}
305
306static double calc_period(struct record *r, struct record *p)
307{
308	double period_ = 0;
309	__u64 period = 0;
310
311	period = r->timestamp - p->timestamp;
312	if (period > 0)
313		period_ = ((double) period / NANOSEC_PER_SEC);
314
315	return period_;
316}
317
318static __u64 calc_pps(struct datarec *r, struct datarec *p, double period_)
319{
320	__u64 packets = 0;
321	__u64 pps = 0;
322
323	if (period_ > 0) {
324		packets = r->processed - p->processed;
325		pps = packets / period_;
326	}
327	return pps;
328}
329
330static __u64 calc_errs_pps(struct datarec *r,
331			    struct datarec *p, double period_)
332{
333	__u64 packets = 0;
334	__u64 pps = 0;
335
336	if (period_ > 0) {
337		packets = r->issue - p->issue;
338		pps = packets / period_;
339	}
340	return pps;
341}
342
343static void stats_print(struct stats_record *stats_rec,
344			struct stats_record *stats_prev,
345			int action, __u32 cfg_opt)
346{
347	unsigned int nr_rxqs = bpf_map__max_entries(rx_queue_index_map);
348	unsigned int nr_cpus = bpf_num_possible_cpus();
349	double pps = 0, err = 0;
350	struct record *rec, *prev;
351	double t;
352	int rxq;
353	int i;
354
355	/* Header */
356	printf("\nRunning XDP on dev:%s (ifindex:%d) action:%s options:%s\n",
357	       ifname, ifindex, action2str(action), options2str(cfg_opt));
358
359	/* stats_global_map */
360	{
361		char *fmt_rx = "%-15s %-7d %'-11.0f %'-10.0f %s\n";
362		char *fm2_rx = "%-15s %-7s %'-11.0f\n";
363		char *errstr = "";
364
365		printf("%-15s %-7s %-11s %-11s\n",
366		       "XDP stats", "CPU", "pps", "issue-pps");
367
368		rec  =  &stats_rec->stats;
369		prev = &stats_prev->stats;
370		t = calc_period(rec, prev);
371		for (i = 0; i < nr_cpus; i++) {
372			struct datarec *r = &rec->cpu[i];
373			struct datarec *p = &prev->cpu[i];
374
375			pps = calc_pps     (r, p, t);
376			err = calc_errs_pps(r, p, t);
377			if (err > 0)
378				errstr = "invalid-ifindex";
379			if (pps > 0)
380				printf(fmt_rx, "XDP-RX CPU",
381					i, pps, err, errstr);
382		}
383		pps  = calc_pps     (&rec->total, &prev->total, t);
384		err  = calc_errs_pps(&rec->total, &prev->total, t);
385		printf(fm2_rx, "XDP-RX CPU", "total", pps, err);
386	}
387
388	/* rx_queue_index_map */
389	printf("\n%-15s %-7s %-11s %-11s\n",
390	       "RXQ stats", "RXQ:CPU", "pps", "issue-pps");
391
392	for (rxq = 0; rxq < nr_rxqs; rxq++) {
393		char *fmt_rx = "%-15s %3d:%-3d %'-11.0f %'-10.0f %s\n";
394		char *fm2_rx = "%-15s %3d:%-3s %'-11.0f\n";
395		char *errstr = "";
396		int rxq_ = rxq;
397
398		/* Last RXQ in map catch overflows */
399		if (rxq_ == nr_rxqs - 1)
400			rxq_ = -1;
401
402		rec  =  &stats_rec->rxq[rxq];
403		prev = &stats_prev->rxq[rxq];
404		t = calc_period(rec, prev);
405		for (i = 0; i < nr_cpus; i++) {
406			struct datarec *r = &rec->cpu[i];
407			struct datarec *p = &prev->cpu[i];
408
409			pps = calc_pps     (r, p, t);
410			err = calc_errs_pps(r, p, t);
411			if (err > 0) {
412				if (rxq_ == -1)
413					errstr = "map-overflow-RXQ";
414				else
415					errstr = "err";
416			}
417			if (pps > 0)
418				printf(fmt_rx, "rx_queue_index",
419				       rxq_, i, pps, err, errstr);
420		}
421		pps  = calc_pps     (&rec->total, &prev->total, t);
422		err  = calc_errs_pps(&rec->total, &prev->total, t);
423		if (pps || err)
424			printf(fm2_rx, "rx_queue_index", rxq_, "sum", pps, err);
425	}
426}
427
428
429/* Pointer swap trick */
430static inline void swap(struct stats_record **a, struct stats_record **b)
431{
432	struct stats_record *tmp;
433
434	tmp = *a;
435	*a = *b;
436	*b = tmp;
437}
438
439static void stats_poll(int interval, int action, __u32 cfg_opt)
440{
441	struct stats_record *record, *prev;
442
443	record = alloc_stats_record();
444	prev   = alloc_stats_record();
445	stats_collect(record);
446
447	while (1) {
448		swap(&prev, &record);
449		stats_collect(record);
450		stats_print(record, prev, action, cfg_opt);
451		sleep(interval);
452	}
453
454	free_stats_record(record);
455	free_stats_record(prev);
456}
457
458
459int main(int argc, char **argv)
460{
461	__u32 cfg_options= NO_TOUCH ; /* Default: Don't touch packet memory */
462	struct bpf_prog_info info = {};
463	__u32 info_len = sizeof(info);
464	int prog_fd, map_fd, opt, err;
465	bool use_separators = true;
466	struct config cfg = { 0 };
467	struct bpf_program *prog;
468	struct bpf_object *obj;
469	struct bpf_map *map;
470	char filename[256];
471	int longindex = 0;
472	int interval = 2;
473	__u32 key = 0;
474
475
476	char action_str_buf[XDP_ACTION_MAX_STRLEN + 1 /* for \0 */] = { 0 };
477	int action = XDP_PASS; /* Default action */
478	char *action_str = NULL;
479
480	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
481
482	obj = bpf_object__open_file(filename, NULL);
483	if (libbpf_get_error(obj))
484		return EXIT_FAIL;
485
486	prog = bpf_object__next_program(obj, NULL);
487	bpf_program__set_type(prog, BPF_PROG_TYPE_XDP);
488
489	err = bpf_object__load(obj);
490	if (err)
491		return EXIT_FAIL;
492	prog_fd = bpf_program__fd(prog);
493
494	map =  bpf_object__find_map_by_name(obj, "config_map");
495	stats_global_map = bpf_object__find_map_by_name(obj, "stats_global_map");
496	rx_queue_index_map = bpf_object__find_map_by_name(obj, "rx_queue_index_map");
497	if (!map || !stats_global_map || !rx_queue_index_map) {
498		printf("finding a map in obj file failed\n");
499		return EXIT_FAIL;
500	}
501	map_fd = bpf_map__fd(map);
502
503	if (!prog_fd) {
504		fprintf(stderr, "ERR: bpf_prog_load_xattr: %s\n", strerror(errno));
505		return EXIT_FAIL;
506	}
507
508	/* Parse commands line args */
509	while ((opt = getopt_long(argc, argv, "FhSrmzd:s:a:",
510				  long_options, &longindex)) != -1) {
511		switch (opt) {
512		case 'd':
513			if (strlen(optarg) >= IF_NAMESIZE) {
514				fprintf(stderr, "ERR: --dev name too long\n");
515				goto error;
516			}
517			ifname = (char *)&ifname_buf;
518			strncpy(ifname, optarg, IF_NAMESIZE);
519			ifindex = if_nametoindex(ifname);
520			if (ifindex == 0) {
521				fprintf(stderr,
522					"ERR: --dev name unknown err(%d):%s\n",
523					errno, strerror(errno));
524				goto error;
525			}
526			break;
527		case 's':
528			interval = atoi(optarg);
529			break;
530		case 'S':
531			xdp_flags |= XDP_FLAGS_SKB_MODE;
532			break;
533		case 'z':
534			use_separators = false;
535			break;
536		case 'a':
537			action_str = (char *)&action_str_buf;
538			strncpy(action_str, optarg, XDP_ACTION_MAX_STRLEN);
539			break;
540		case 'r':
541			cfg_options |= READ_MEM;
542			break;
543		case 'm':
544			cfg_options |= SWAP_MAC;
545			break;
546		case 'F':
547			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
548			break;
549		case 'h':
550		error:
551		default:
552			usage(argv);
553			return EXIT_FAIL_OPTION;
554		}
555	}
556
557	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
558		xdp_flags |= XDP_FLAGS_DRV_MODE;
559
560	/* Required option */
561	if (ifindex == -1) {
562		fprintf(stderr, "ERR: required option --dev missing\n");
563		usage(argv);
564		return EXIT_FAIL_OPTION;
565	}
566	cfg.ifindex = ifindex;
567
568	/* Parse action string */
569	if (action_str) {
570		action = parse_xdp_action(action_str);
571		if (action < 0) {
572			fprintf(stderr, "ERR: Invalid XDP --action: %s\n",
573				action_str);
574			list_xdp_actions();
575			return EXIT_FAIL_OPTION;
576		}
577	}
578	cfg.action = action;
579
580	/* XDP_TX requires changing MAC-addrs, else HW may drop */
581	if (action == XDP_TX)
582		cfg_options |= SWAP_MAC;
583	cfg.options = cfg_options;
584
585	/* Trick to pretty printf with thousands separators use %' */
586	if (use_separators)
587		setlocale(LC_NUMERIC, "en_US");
588
589	/* User-side setup ifindex in config_map */
590	err = bpf_map_update_elem(map_fd, &key, &cfg, 0);
591	if (err) {
592		fprintf(stderr, "Store config failed (err:%d)\n", err);
593		exit(EXIT_FAIL_BPF);
594	}
595
596	/* Remove XDP program when program is interrupted or killed */
597	signal(SIGINT, int_exit);
598	signal(SIGTERM, int_exit);
599
600	if (bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL) < 0) {
601		fprintf(stderr, "link set xdp fd failed\n");
602		return EXIT_FAIL_XDP;
603	}
604
605	err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
606	if (err) {
607		printf("can't get prog info - %s\n", strerror(errno));
608		return err;
609	}
610	prog_id = info.id;
611
612	stats_poll(interval, action, cfg_options);
613	return EXIT_OK;
614}