1 files changed, 792 insertions, 0 deletions

diff --git a/samples/bpf/xdp_monitor_user.c b/samples/bpf/xdp_monitor_user.c
new file mode 100644
index 000000000..03d0a1829
--- /dev/null
+++ b/samples/bpf/xdp_monitor_user.c
@@ -0,0 +1,792 @@
+/* SPDX-License-Identifier: GPL-2.0
+ * Copyright(c) 2017 Jesper Dangaard Brouer, Red Hat, Inc.
+ */
+static const char *__doc__=
+ "XDP monitor tool, based on tracepoints\n"
+;
+
+static const char *__doc_err_only__=
+ " NOTICE: Only tracking XDP redirect errors\n"
+ "         Enable TX success stats via '--stats'\n"
+ "         (which comes with a per packet processing overhead)\n"
+;
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <locale.h>
+
+#include <sys/resource.h>
+#include <getopt.h>
+#include <net/if.h>
+#include <time.h>
+
+#include <signal.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "bpf_util.h"
+
+enum map_type {
+	REDIRECT_ERR_CNT,
+	EXCEPTION_CNT,
+	CPUMAP_ENQUEUE_CNT,
+	CPUMAP_KTHREAD_CNT,
+	DEVMAP_XMIT_CNT,
+};
+
+static const char *const map_type_strings[] = {
+	[REDIRECT_ERR_CNT] = "redirect_err_cnt",
+	[EXCEPTION_CNT] = "exception_cnt",
+	[CPUMAP_ENQUEUE_CNT] = "cpumap_enqueue_cnt",
+	[CPUMAP_KTHREAD_CNT] = "cpumap_kthread_cnt",
+	[DEVMAP_XMIT_CNT] = "devmap_xmit_cnt",
+};
+
+#define NUM_MAP 5
+#define NUM_TP 8
+
+static int tp_cnt;
+static int map_cnt;
+static int verbose = 1;
+static bool debug = false;
+struct bpf_map *map_data[NUM_MAP] = {};
+struct bpf_link *tp_links[NUM_TP] = {};
+struct bpf_object *obj;
+
+static const struct option long_options[] = {
+	{"help",	no_argument,		NULL, 'h' },
+	{"debug",	no_argument,		NULL, 'D' },
+	{"stats",	no_argument,		NULL, 'S' },
+	{"sec", 	required_argument,	NULL, 's' },
+	{0, 0, NULL,  0 }
+};
+
+static void int_exit(int sig)
+{
+	/* Detach tracepoints */
+	while (tp_cnt)
+		bpf_link__destroy(tp_links[--tp_cnt]);
+
+	bpf_object__close(obj);
+	exit(0);
+}
+
+/* C standard specifies two constants, EXIT_SUCCESS(0) and EXIT_FAILURE(1) */
+#define EXIT_FAIL_MEM	5
+
+static void usage(char *argv[])
+{
+	int i;
+	printf("\nDOCUMENTATION:\n%s\n", __doc__);
+	printf("\n");
+	printf(" Usage: %s (options-see-below)\n",
+	       argv[0]);
+	printf(" Listing options:\n");
+	for (i = 0; long_options[i].name != 0; i++) {
+		printf(" --%-15s", long_options[i].name);
+		if (long_options[i].flag != NULL)
+			printf(" flag (internal value:%d)",
+			       *long_options[i].flag);
+		else
+			printf("short-option: -%c",
+			       long_options[i].val);
+		printf("\n");
+	}
+	printf("\n");
+}
+
+#define NANOSEC_PER_SEC 1000000000 /* 10^9 */
+static __u64 gettime(void)
+{
+	struct timespec t;
+	int res;
+
+	res = clock_gettime(CLOCK_MONOTONIC, &t);
+	if (res < 0) {
+		fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
+		exit(EXIT_FAILURE);
+	}
+	return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
+}
+
+enum {
+	REDIR_SUCCESS = 0,
+	REDIR_ERROR = 1,
+};
+#define REDIR_RES_MAX 2
+static const char *redir_names[REDIR_RES_MAX] = {
+	[REDIR_SUCCESS]	= "Success",
+	[REDIR_ERROR]	= "Error",
+};
+static const char *err2str(int err)
+{
+	if (err < REDIR_RES_MAX)
+		return redir_names[err];
+	return NULL;
+}
+/* enum xdp_action */
+#define XDP_UNKNOWN	XDP_REDIRECT + 1
+#define XDP_ACTION_MAX (XDP_UNKNOWN + 1)
+static const char *xdp_action_names[XDP_ACTION_MAX] = {
+	[XDP_ABORTED]	= "XDP_ABORTED",
+	[XDP_DROP]	= "XDP_DROP",
+	[XDP_PASS]	= "XDP_PASS",
+	[XDP_TX]	= "XDP_TX",
+	[XDP_REDIRECT]	= "XDP_REDIRECT",
+	[XDP_UNKNOWN]	= "XDP_UNKNOWN",
+};
+static const char *action2str(int action)
+{
+	if (action < XDP_ACTION_MAX)
+		return xdp_action_names[action];
+	return NULL;
+}
+
+/* Common stats data record shared with _kern.c */
+struct datarec {
+	__u64 processed;
+	__u64 dropped;
+	__u64 info;
+	__u64 err;
+};
+#define MAX_CPUS 64
+
+/* Userspace structs for collection of stats from maps */
+struct record {
+	__u64 timestamp;
+	struct datarec total;
+	struct datarec *cpu;
+};
+struct u64rec {
+	__u64 processed;
+};
+struct record_u64 {
+	/* record for _kern side __u64 values */
+	__u64 timestamp;
+	struct u64rec total;
+	struct u64rec *cpu;
+};
+
+struct stats_record {
+	struct record_u64 xdp_redirect[REDIR_RES_MAX];
+	struct record_u64 xdp_exception[XDP_ACTION_MAX];
+	struct record xdp_cpumap_kthread;
+	struct record xdp_cpumap_enqueue[MAX_CPUS];
+	struct record xdp_devmap_xmit;
+};
+
+static bool map_collect_record(int fd, __u32 key, struct record *rec)
+{
+	/* For percpu maps, userspace gets a value per possible CPU */
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	struct datarec values[nr_cpus];
+	__u64 sum_processed = 0;
+	__u64 sum_dropped = 0;
+	__u64 sum_info = 0;
+	__u64 sum_err = 0;
+	int i;
+
+	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
+		fprintf(stderr,
+			"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
+		return false;
+	}
+	/* Get time as close as possible to reading map contents */
+	rec->timestamp = gettime();
+
+	/* Record and sum values from each CPU */
+	for (i = 0; i < nr_cpus; i++) {
+		rec->cpu[i].processed = values[i].processed;
+		sum_processed        += values[i].processed;
+		rec->cpu[i].dropped = values[i].dropped;
+		sum_dropped        += values[i].dropped;
+		rec->cpu[i].info = values[i].info;
+		sum_info        += values[i].info;
+		rec->cpu[i].err = values[i].err;
+		sum_err        += values[i].err;
+	}
+	rec->total.processed = sum_processed;
+	rec->total.dropped   = sum_dropped;
+	rec->total.info      = sum_info;
+	rec->total.err       = sum_err;
+	return true;
+}
+
+static bool map_collect_record_u64(int fd, __u32 key, struct record_u64 *rec)
+{
+	/* For percpu maps, userspace gets a value per possible CPU */
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	struct u64rec values[nr_cpus];
+	__u64 sum_total = 0;
+	int i;
+
+	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
+		fprintf(stderr,
+			"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
+		return false;
+	}
+	/* Get time as close as possible to reading map contents */
+	rec->timestamp = gettime();
+
+	/* Record and sum values from each CPU */
+	for (i = 0; i < nr_cpus; i++) {
+		rec->cpu[i].processed = values[i].processed;
+		sum_total            += values[i].processed;
+	}
+	rec->total.processed = sum_total;
+	return true;
+}
+
+static double calc_period(struct record *r, struct record *p)
+{
+	double period_ = 0;
+	__u64 period = 0;
+
+	period = r->timestamp - p->timestamp;
+	if (period > 0)
+		period_ = ((double) period / NANOSEC_PER_SEC);
+
+	return period_;
+}
+
+static double calc_period_u64(struct record_u64 *r, struct record_u64 *p)
+{
+	double period_ = 0;
+	__u64 period = 0;
+
+	period = r->timestamp - p->timestamp;
+	if (period > 0)
+		period_ = ((double) period / NANOSEC_PER_SEC);
+
+	return period_;
+}
+
+static double calc_pps(struct datarec *r, struct datarec *p, double period)
+{
+	__u64 packets = 0;
+	double pps = 0;
+
+	if (period > 0) {
+		packets = r->processed - p->processed;
+		pps = packets / period;
+	}
+	return pps;
+}
+
+static double calc_pps_u64(struct u64rec *r, struct u64rec *p, double period)
+{
+	__u64 packets = 0;
+	double pps = 0;
+
+	if (period > 0) {
+		packets = r->processed - p->processed;
+		pps = packets / period;
+	}
+	return pps;
+}
+
+static double calc_drop(struct datarec *r, struct datarec *p, double period)
+{
+	__u64 packets = 0;
+	double pps = 0;
+
+	if (period > 0) {
+		packets = r->dropped - p->dropped;
+		pps = packets / period;
+	}
+	return pps;
+}
+
+static double calc_info(struct datarec *r, struct datarec *p, double period)
+{
+	__u64 packets = 0;
+	double pps = 0;
+
+	if (period > 0) {
+		packets = r->info - p->info;
+		pps = packets / period;
+	}
+	return pps;
+}
+
+static double calc_err(struct datarec *r, struct datarec *p, double period)
+{
+	__u64 packets = 0;
+	double pps = 0;
+
+	if (period > 0) {
+		packets = r->err - p->err;
+		pps = packets / period;
+	}
+	return pps;
+}
+
+static void stats_print(struct stats_record *stats_rec,
+			struct stats_record *stats_prev,
+			bool err_only)
+{
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	int rec_i = 0, i, to_cpu;
+	double t = 0, pps = 0;
+
+	/* Header */
+	printf("%-15s %-7s %-12s %-12s %-9s\n",
+	       "XDP-event", "CPU:to", "pps", "drop-pps", "extra-info");
+
+	/* tracepoint: xdp:xdp_redirect_* */
+	if (err_only)
+		rec_i = REDIR_ERROR;
+
+	for (; rec_i < REDIR_RES_MAX; rec_i++) {
+		struct record_u64 *rec, *prev;
+		char *fmt1 = "%-15s %-7d %'-12.0f %'-12.0f %s\n";
+		char *fmt2 = "%-15s %-7s %'-12.0f %'-12.0f %s\n";
+
+		rec  =  &stats_rec->xdp_redirect[rec_i];
+		prev = &stats_prev->xdp_redirect[rec_i];
+		t = calc_period_u64(rec, prev);
+
+		for (i = 0; i < nr_cpus; i++) {
+			struct u64rec *r = &rec->cpu[i];
+			struct u64rec *p = &prev->cpu[i];
+
+			pps = calc_pps_u64(r, p, t);
+			if (pps > 0)
+				printf(fmt1, "XDP_REDIRECT", i,
+				       rec_i ? 0.0: pps, rec_i ? pps : 0.0,
+				       err2str(rec_i));
+		}
+		pps = calc_pps_u64(&rec->total, &prev->total, t);
+		printf(fmt2, "XDP_REDIRECT", "total",
+		       rec_i ? 0.0: pps, rec_i ? pps : 0.0, err2str(rec_i));
+	}
+
+	/* tracepoint: xdp:xdp_exception */
+	for (rec_i = 0; rec_i < XDP_ACTION_MAX; rec_i++) {
+		struct record_u64 *rec, *prev;
+		char *fmt1 = "%-15s %-7d %'-12.0f %'-12.0f %s\n";
+		char *fmt2 = "%-15s %-7s %'-12.0f %'-12.0f %s\n";
+
+		rec  =  &stats_rec->xdp_exception[rec_i];
+		prev = &stats_prev->xdp_exception[rec_i];
+		t = calc_period_u64(rec, prev);
+
+		for (i = 0; i < nr_cpus; i++) {
+			struct u64rec *r = &rec->cpu[i];
+			struct u64rec *p = &prev->cpu[i];
+
+			pps = calc_pps_u64(r, p, t);
+			if (pps > 0)
+				printf(fmt1, "Exception", i,
+				       0.0, pps, action2str(rec_i));
+		}
+		pps = calc_pps_u64(&rec->total, &prev->total, t);
+		if (pps > 0)
+			printf(fmt2, "Exception", "total",
+			       0.0, pps, action2str(rec_i));
+	}
+
+	/* cpumap enqueue stats */
+	for (to_cpu = 0; to_cpu < MAX_CPUS; to_cpu++) {
+		char *fmt1 = "%-15s %3d:%-3d %'-12.0f %'-12.0f %'-10.2f %s\n";
+		char *fmt2 = "%-15s %3s:%-3d %'-12.0f %'-12.0f %'-10.2f %s\n";
+		struct record *rec, *prev;
+		char *info_str = "";
+		double drop, info;
+
+		rec  =  &stats_rec->xdp_cpumap_enqueue[to_cpu];
+		prev = &stats_prev->xdp_cpumap_enqueue[to_cpu];
+		t = calc_period(rec, prev);
+		for (i = 0; i < nr_cpus; i++) {
+			struct datarec *r = &rec->cpu[i];
+			struct datarec *p = &prev->cpu[i];
+
+			pps  = calc_pps(r, p, t);
+			drop = calc_drop(r, p, t);
+			info = calc_info(r, p, t);
+			if (info > 0) {
+				info_str = "bulk-average";
+				info = pps / info; /* calc average bulk size */
+			}
+			if (pps > 0)
+				printf(fmt1, "cpumap-enqueue",
+				       i, to_cpu, pps, drop, info, info_str);
+		}
+		pps = calc_pps(&rec->total, &prev->total, t);
+		if (pps > 0) {
+			drop = calc_drop(&rec->total, &prev->total, t);
+			info = calc_info(&rec->total, &prev->total, t);
+			if (info > 0) {
+				info_str = "bulk-average";
+				info = pps / info; /* calc average bulk size */
+			}
+			printf(fmt2, "cpumap-enqueue",
+			       "sum", to_cpu, pps, drop, info, info_str);
+		}
+	}
+
+	/* cpumap kthread stats */
+	{
+		char *fmt1 = "%-15s %-7d %'-12.0f %'-12.0f %'-10.0f %s\n";
+		char *fmt2 = "%-15s %-7s %'-12.0f %'-12.0f %'-10.0f %s\n";
+		struct record *rec, *prev;
+		double drop, info;
+		char *i_str = "";
+
+		rec  =  &stats_rec->xdp_cpumap_kthread;
+		prev = &stats_prev->xdp_cpumap_kthread;
+		t = calc_period(rec, prev);
+		for (i = 0; i < nr_cpus; i++) {
+			struct datarec *r = &rec->cpu[i];
+			struct datarec *p = &prev->cpu[i];
+
+			pps  = calc_pps(r, p, t);
+			drop = calc_drop(r, p, t);
+			info = calc_info(r, p, t);
+			if (info > 0)
+				i_str = "sched";
+			if (pps > 0 || drop > 0)
+				printf(fmt1, "cpumap-kthread",
+				       i, pps, drop, info, i_str);
+		}
+		pps = calc_pps(&rec->total, &prev->total, t);
+		drop = calc_drop(&rec->total, &prev->total, t);
+		info = calc_info(&rec->total, &prev->total, t);
+		if (info > 0)
+			i_str = "sched-sum";
+		printf(fmt2, "cpumap-kthread", "total", pps, drop, info, i_str);
+	}
+
+	/* devmap ndo_xdp_xmit stats */
+	{
+		char *fmt1 = "%-15s %-7d %'-12.0f %'-12.0f %'-10.2f %s %s\n";
+		char *fmt2 = "%-15s %-7s %'-12.0f %'-12.0f %'-10.2f %s %s\n";
+		struct record *rec, *prev;
+		double drop, info, err;
+		char *i_str = "";
+		char *err_str = "";
+
+		rec  =  &stats_rec->xdp_devmap_xmit;
+		prev = &stats_prev->xdp_devmap_xmit;
+		t = calc_period(rec, prev);
+		for (i = 0; i < nr_cpus; i++) {
+			struct datarec *r = &rec->cpu[i];
+			struct datarec *p = &prev->cpu[i];
+
+			pps  = calc_pps(r, p, t);
+			drop = calc_drop(r, p, t);
+			info = calc_info(r, p, t);
+			err  = calc_err(r, p, t);
+			if (info > 0) {
+				i_str = "bulk-average";
+				info = (pps+drop) / info; /* calc avg bulk */
+			}
+			if (err > 0)
+				err_str = "drv-err";
+			if (pps > 0 || drop > 0)
+				printf(fmt1, "devmap-xmit",
+				       i, pps, drop, info, i_str, err_str);
+		}
+		pps = calc_pps(&rec->total, &prev->total, t);
+		drop = calc_drop(&rec->total, &prev->total, t);
+		info = calc_info(&rec->total, &prev->total, t);
+		err  = calc_err(&rec->total, &prev->total, t);
+		if (info > 0) {
+			i_str = "bulk-average";
+			info = (pps+drop) / info; /* calc avg bulk */
+		}
+		if (err > 0)
+			err_str = "drv-err";
+		printf(fmt2, "devmap-xmit", "total", pps, drop,
+		       info, i_str, err_str);
+	}
+
+	printf("\n");
+}
+
+static bool stats_collect(struct stats_record *rec)
+{
+	int fd;
+	int i;
+
+	/* TODO: Detect if someone unloaded the perf event_fd's, as
+	 * this can happen by someone running perf-record -e
+	 */
+
+	fd = bpf_map__fd(map_data[REDIRECT_ERR_CNT]);
+	for (i = 0; i < REDIR_RES_MAX; i++)
+		map_collect_record_u64(fd, i, &rec->xdp_redirect[i]);
+
+	fd = bpf_map__fd(map_data[EXCEPTION_CNT]);
+	for (i = 0; i < XDP_ACTION_MAX; i++) {
+		map_collect_record_u64(fd, i, &rec->xdp_exception[i]);
+	}
+
+	fd = bpf_map__fd(map_data[CPUMAP_ENQUEUE_CNT]);
+	for (i = 0; i < MAX_CPUS; i++)
+		map_collect_record(fd, i, &rec->xdp_cpumap_enqueue[i]);
+
+	fd = bpf_map__fd(map_data[CPUMAP_KTHREAD_CNT]);
+	map_collect_record(fd, 0, &rec->xdp_cpumap_kthread);
+
+	fd = bpf_map__fd(map_data[DEVMAP_XMIT_CNT]);
+	map_collect_record(fd, 0, &rec->xdp_devmap_xmit);
+
+	return true;
+}
+
+static void *alloc_rec_per_cpu(int record_size)
+{
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	void *array;
+
+	array = calloc(nr_cpus, record_size);
+	if (!array) {
+		fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
+		exit(EXIT_FAIL_MEM);
+	}
+	return array;
+}
+
+static struct stats_record *alloc_stats_record(void)
+{
+	struct stats_record *rec;
+	int rec_sz;
+	int i;
+
+	/* Alloc main stats_record structure */
+	rec = calloc(1, sizeof(*rec));
+	if (!rec) {
+		fprintf(stderr, "Mem alloc error\n");
+		exit(EXIT_FAIL_MEM);
+	}
+
+	/* Alloc stats stored per CPU for each record */
+	rec_sz = sizeof(struct u64rec);
+	for (i = 0; i < REDIR_RES_MAX; i++)
+		rec->xdp_redirect[i].cpu = alloc_rec_per_cpu(rec_sz);
+
+	for (i = 0; i < XDP_ACTION_MAX; i++)
+		rec->xdp_exception[i].cpu = alloc_rec_per_cpu(rec_sz);
+
+	rec_sz = sizeof(struct datarec);
+	rec->xdp_cpumap_kthread.cpu = alloc_rec_per_cpu(rec_sz);
+	rec->xdp_devmap_xmit.cpu    = alloc_rec_per_cpu(rec_sz);
+
+	for (i = 0; i < MAX_CPUS; i++)
+		rec->xdp_cpumap_enqueue[i].cpu = alloc_rec_per_cpu(rec_sz);
+
+	return rec;
+}
+
+static void free_stats_record(struct stats_record *r)
+{
+	int i;
+
+	for (i = 0; i < REDIR_RES_MAX; i++)
+		free(r->xdp_redirect[i].cpu);
+
+	for (i = 0; i < XDP_ACTION_MAX; i++)
+		free(r->xdp_exception[i].cpu);
+
+	free(r->xdp_cpumap_kthread.cpu);
+	free(r->xdp_devmap_xmit.cpu);
+
+	for (i = 0; i < MAX_CPUS; i++)
+		free(r->xdp_cpumap_enqueue[i].cpu);
+
+	free(r);
+}
+
+/* Pointer swap trick */
+static inline void swap(struct stats_record **a, struct stats_record **b)
+{
+	struct stats_record *tmp;
+
+	tmp = *a;
+	*a = *b;
+	*b = tmp;
+}
+
+static void stats_poll(int interval, bool err_only)
+{
+	struct stats_record *rec, *prev;
+
+	rec  = alloc_stats_record();
+	prev = alloc_stats_record();
+	stats_collect(rec);
+
+	if (err_only)
+		printf("\n%s\n", __doc_err_only__);
+
+	/* Trick to pretty printf with thousands separators use %' */
+	setlocale(LC_NUMERIC, "en_US");
+
+	/* Header */
+	if (verbose)
+		printf("\n%s", __doc__);
+
+	/* TODO Need more advanced stats on error types */
+	if (verbose) {
+		printf(" - Stats map0: %s\n", bpf_map__name(map_data[0]));
+		printf(" - Stats map1: %s\n", bpf_map__name(map_data[1]));
+		printf("\n");
+	}
+	fflush(stdout);
+
+	while (1) {
+		swap(&prev, &rec);
+		stats_collect(rec);
+		stats_print(rec, prev, err_only);
+		fflush(stdout);
+		sleep(interval);
+	}
+
+	free_stats_record(rec);
+	free_stats_record(prev);
+}
+
+static void print_bpf_prog_info(void)
+{
+	struct bpf_program *prog;
+	struct bpf_map *map;
+	int i = 0;
+
+	/* Prog info */
+	printf("Loaded BPF prog have %d bpf program(s)\n", tp_cnt);
+	bpf_object__for_each_program(prog, obj) {
+		printf(" - prog_fd[%d] = fd(%d)\n", i, bpf_program__fd(prog));
+		i++;
+	}
+
+	i = 0;
+	/* Maps info */
+	printf("Loaded BPF prog have %d map(s)\n", map_cnt);
+	bpf_object__for_each_map(map, obj) {
+		const char *name = bpf_map__name(map);
+		int fd		 = bpf_map__fd(map);
+
+		printf(" - map_data[%d] = fd(%d) name:%s\n", i, fd, name);
+		i++;
+	}
+
+	/* Event info */
+	printf("Searching for (max:%d) event file descriptor(s)\n", tp_cnt);
+	for (i = 0; i < tp_cnt; i++) {
+		int fd = bpf_link__fd(tp_links[i]);
+
+		if (fd != -1)
+			printf(" - event_fd[%d] = fd(%d)\n", i, fd);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+	struct bpf_program *prog;
+	int longindex = 0, opt;
+	int ret = EXIT_FAILURE;
+	enum map_type type;
+	char filename[256];
+
+	/* Default settings: */
+	bool errors_only = true;
+	int interval = 2;
+
+	/* Parse commands line args */
+	while ((opt = getopt_long(argc, argv, "hDSs:",
+				  long_options, &longindex)) != -1) {
+		switch (opt) {
+		case 'D':
+			debug = true;
+			break;
+		case 'S':
+			errors_only = false;
+			break;
+		case 's':
+			interval = atoi(optarg);
+			break;
+		case 'h':
+		default:
+			usage(argv);
+			return ret;
+		}
+	}
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
+		perror("setrlimit(RLIMIT_MEMLOCK)");
+		return ret;
+	}
+
+	/* Remove tracepoint program when program is interrupted or killed */
+	signal(SIGINT, int_exit);
+	signal(SIGTERM, int_exit);
+
+	obj = bpf_object__open_file(filename, NULL);
+	if (libbpf_get_error(obj)) {
+		printf("ERROR: opening BPF object file failed\n");
+		obj = NULL;
+		goto cleanup;
+	}
+
+	/* load BPF program */
+	if (bpf_object__load(obj)) {
+		printf("ERROR: loading BPF object file failed\n");
+		goto cleanup;
+	}
+
+	for (type = 0; type < NUM_MAP; type++) {
+		map_data[type] =
+			bpf_object__find_map_by_name(obj, map_type_strings[type]);
+
+		if (libbpf_get_error(map_data[type])) {
+			printf("ERROR: finding a map in obj file failed\n");
+			goto cleanup;
+		}
+		map_cnt++;
+	}
+
+	bpf_object__for_each_program(prog, obj) {
+		tp_links[tp_cnt] = bpf_program__attach(prog);
+		if (libbpf_get_error(tp_links[tp_cnt])) {
+			printf("ERROR: bpf_program__attach failed\n");
+			tp_links[tp_cnt] = NULL;
+			goto cleanup;
+		}
+		tp_cnt++;
+	}
+
+	if (debug) {
+		print_bpf_prog_info();
+	}
+
+	/* Unload/stop tracepoint event by closing bpf_link's */
+	if (errors_only) {
+		/* The bpf_link[i] depend on the order of
+		 * the functions was defined in _kern.c
+		 */
+		bpf_link__destroy(tp_links[2]);	/* tracepoint/xdp/xdp_redirect */
+		tp_links[2] = NULL;
+
+		bpf_link__destroy(tp_links[3]);	/* tracepoint/xdp/xdp_redirect_map */
+		tp_links[3] = NULL;
+	}
+
+	stats_poll(interval, errors_only);
+
+	ret = EXIT_SUCCESS;
+
+cleanup:
+	/* Detach tracepoints */
+	while (tp_cnt)
+		bpf_link__destroy(tp_links[--tp_cnt]);
+
+	bpf_object__close(obj);
+	return ret;
+}