samples: bpf: convert some XDP samples from bpf_load to libbpf

Now that we can use full powers of libbpf in BPF samples, we
should perhaps make the simplest XDP programs not depend on
bpf_load helpers.  This way newcomers will be exposed to the
recommended library from the start.

Use of bpf_prog_load_xattr() will also make it trivial to later
on request offload of the programs by simply adding ifindex to
the xattr.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 8ce72d211c3e4d343e7b1fb9aae2b36a90a51466..9e255ca4059ae458b8ef81e25ae68b9e31c20f2c 100644 (file)
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -79,9 +79,9 @@ test_cgrp2_attach-objs := test_cgrp2_attach.o $(LIBBPF)
 test_cgrp2_attach2-objs := test_cgrp2_attach2.o $(LIBBPF) $(CGROUP_HELPERS)
 test_cgrp2_sock-objs := test_cgrp2_sock.o $(LIBBPF)
 test_cgrp2_sock2-objs := bpf_load.o $(LIBBPF) test_cgrp2_sock2.o
-xdp1-objs := bpf_load.o $(LIBBPF) xdp1_user.o
+xdp1-objs := xdp1_user.o $(LIBBPF)
 # reuse xdp1 source intentionally
-xdp2-objs := bpf_load.o $(LIBBPF) xdp1_user.o
+xdp2-objs := xdp1_user.o $(LIBBPF)
 xdp_router_ipv4-objs := bpf_load.o $(LIBBPF) xdp_router_ipv4_user.o
 test_current_task_under_cgroup-objs := bpf_load.o $(LIBBPF) $(CGROUP_HELPERS) \
                                       test_current_task_under_cgroup_user.o
@@ -96,10 +96,10 @@ xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o
 xdp_redirect_map-objs := bpf_load.o $(LIBBPF) xdp_redirect_map_user.o
 xdp_redirect_cpu-objs := bpf_load.o $(LIBBPF) xdp_redirect_cpu_user.o
 xdp_monitor-objs := bpf_load.o $(LIBBPF) xdp_monitor_user.o
-xdp_rxq_info-objs := bpf_load.o $(LIBBPF) xdp_rxq_info_user.o
+xdp_rxq_info-objs := xdp_rxq_info_user.o $(LIBBPF)
 syscall_tp-objs := bpf_load.o $(LIBBPF) syscall_tp_user.o
 cpustat-objs := bpf_load.o $(LIBBPF) cpustat_user.o
-xdp_adjust_tail-objs := bpf_load.o $(LIBBPF) xdp_adjust_tail_user.o
+xdp_adjust_tail-objs := xdp_adjust_tail_user.o $(LIBBPF)
 xdpsock-objs := bpf_load.o $(LIBBPF) xdpsock_user.o
 xdp_fwd-objs := bpf_load.o $(LIBBPF) xdp_fwd_user.o
 

diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index b901ee2b33362d4dcd13c28fa3c922c73d19918d..b02c531510ed9a0b88963f749a5d32e8dc0b3c16 100644 (file)
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -16,9 +16,9 @@
 #include <libgen.h>
 #include <sys/resource.h>
 
-#include "bpf_load.h"
 #include "bpf_util.h"
-#include "libbpf.h"
+#include "bpf/bpf.h"
+#include "bpf/libbpf.h"
 
 static int ifindex;
 static __u32 xdp_flags;
@@ -31,7 +31,7 @@ static void int_exit(int sig)
 
 /* simple per-protocol drop counter
  */
-static void poll_stats(int interval)
+static void poll_stats(int map_fd, int interval)
 {
        unsigned int nr_cpus = bpf_num_possible_cpus();
        const unsigned int nr_keys = 256;
@@ -47,7 +47,7 @@ static void poll_stats(int interval)
                for (key = 0; key < nr_keys; key++) {
                        __u64 sum = 0;
 
-                       assert(bpf_map_lookup_elem(map_fd[0], &key, values) == 0);
+                       assert(bpf_map_lookup_elem(map_fd, &key, values) == 0);
                        for (i = 0; i < nr_cpus; i++)
                                sum += (values[i] - prev[key][i]);
                        if (sum)
@@ -71,9 +71,14 @@ static void usage(const char *prog)
 int main(int argc, char **argv)
 {
        struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+       struct bpf_prog_load_attr prog_load_attr = {
+               .prog_type      = BPF_PROG_TYPE_XDP,
+       };
        const char *optstr = "SN";
+       int prog_fd, map_fd, opt;
+       struct bpf_object *obj;
+       struct bpf_map *map;
        char filename[256];
-       int opt;
 
        while ((opt = getopt(argc, argv, optstr)) != -1) {
                switch (opt) {
@@ -102,13 +107,19 @@ int main(int argc, char **argv)
        ifindex = strtoul(argv[optind], NULL, 0);
 
        snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+       prog_load_attr.file = filename;
 
-       if (load_bpf_file(filename)) {
-               printf("%s", bpf_log_buf);
+       if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
+               return 1;
+
+       map = bpf_map__next(NULL, obj);
+       if (!map) {
+               printf("finding a map in obj file failed\n");
                return 1;
        }
+       map_fd = bpf_map__fd(map);
 
-       if (!prog_fd[0]) {
+       if (!prog_fd) {
                printf("load_bpf_file: %s\n", strerror(errno));
                return 1;
        }
@@ -116,12 +127,12 @@ int main(int argc, char **argv)
        signal(SIGINT, int_exit);
        signal(SIGTERM, int_exit);
 
-       if (bpf_set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
+       if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
                printf("link set xdp fd failed\n");
                return 1;
        }
 
-       poll_stats(2);
+       poll_stats(map_fd, 2);
 
        return 0;
 }

diff --git a/samples/bpf/xdp_adjust_tail_user.c b/samples/bpf/xdp_adjust_tail_user.c
index f621a541b57451c61e5ef1d0f9d99433d541cd30..3042ce37dae8ec14c149f21ad9a96191ed49d217 100644 (file)
--- a/samples/bpf/xdp_adjust_tail_user.c
+++ b/samples/bpf/xdp_adjust_tail_user.c
@@ -18,9 +18,8 @@
 #include <netinet/ether.h>
 #include <unistd.h>
 #include <time.h>
-#include "bpf_load.h"
-#include "libbpf.h"
-#include "bpf_util.h"
+#include "bpf/bpf.h"
+#include "bpf/libbpf.h"
 
 #define STATS_INTERVAL_S 2U
 
@@ -36,7 +35,7 @@ static void int_exit(int sig)
 
 /* simple "icmp packet too big sent" counter
  */
-static void poll_stats(unsigned int kill_after_s)
+static void poll_stats(unsigned int map_fd, unsigned int kill_after_s)
 {
        time_t started_at = time(NULL);
        __u64 value = 0;
@@ -46,7 +45,7 @@ static void poll_stats(unsigned int kill_after_s)
        while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {
                sleep(STATS_INTERVAL_S);
 
-               assert(bpf_map_lookup_elem(map_fd[0], &key, &value) == 0);
+               assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0);
 
                printf("icmp \"packet too big\" sent: %10llu pkts\n", value);
        }
@@ -66,14 +65,17 @@ static void usage(const char *cmd)
 
 int main(int argc, char **argv)
 {
+       struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+       struct bpf_prog_load_attr prog_load_attr = {
+               .prog_type      = BPF_PROG_TYPE_XDP,
+       };
        unsigned char opt_flags[256] = {};
        unsigned int kill_after_s = 0;
        const char *optstr = "i:T:SNh";
-       struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+       int i, prog_fd, map_fd, opt;
+       struct bpf_object *obj;
+       struct bpf_map *map;
        char filename[256];
-       int opt;
-       int i;
-
 
        for (i = 0; i < strlen(optstr); i++)
                if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
@@ -115,13 +117,19 @@ int main(int argc, char **argv)
        }
 
        snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+       prog_load_attr.file = filename;
+
+       if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
+               return 1;
 
-       if (load_bpf_file(filename)) {
-               printf("%s", bpf_log_buf);
+       map = bpf_map__next(NULL, obj);
+       if (!map) {
+               printf("finding a map in obj file failed\n");
                return 1;
        }
+       map_fd = bpf_map__fd(map);
 
-       if (!prog_fd[0]) {
+       if (!prog_fd) {
                printf("load_bpf_file: %s\n", strerror(errno));
                return 1;
        }
@@ -129,12 +137,12 @@ int main(int argc, char **argv)
        signal(SIGINT, int_exit);
        signal(SIGTERM, int_exit);
 
-       if (bpf_set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
+       if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
                printf("link set xdp fd failed\n");
                return 1;
        }
 
-       poll_stats(kill_after_s);
+       poll_stats(map_fd, kill_after_s);
 
        bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
 

diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c
index 478d95412de438be21908ed5363d72387187dbca..e4e9ba52bff02c457410543424b0f90148a01730 100644 (file)
--- a/samples/bpf/xdp_rxq_info_user.c
+++ b/samples/bpf/xdp_rxq_info_user.c
@@ -22,8 +22,8 @@ static const char *__doc__ = " XDP RX-queue info extract example\n\n"
 #include <arpa/inet.h>
 #include <linux/if_link.h>
 
-#include "libbpf.h"
-#include "bpf_load.h"
+#include "bpf/bpf.h"
+#include "bpf/libbpf.h"
 #include "bpf_util.h"
 
 static int ifindex = -1;
@@ -32,6 +32,9 @@ static char *ifname;
 
 static __u32 xdp_flags;
 
+static struct bpf_map *stats_global_map;
+static struct bpf_map *rx_queue_index_map;
+
 /* Exit return codes */
 #define EXIT_OK                0
 #define EXIT_FAIL              1
@@ -174,7 +177,7 @@ static struct datarec *alloc_record_per_cpu(void)
 
 static struct record *alloc_record_per_rxq(void)
 {
-       unsigned int nr_rxqs = map_data[2].def.max_entries;
+       unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
        struct record *array;
        size_t size;
 
@@ -190,7 +193,7 @@ static struct record *alloc_record_per_rxq(void)
 
 static struct stats_record *alloc_stats_record(void)
 {
-       unsigned int nr_rxqs = map_data[2].def.max_entries;
+       unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
        struct stats_record *rec;
        int i;
 
@@ -210,7 +213,7 @@ static struct stats_record *alloc_stats_record(void)
 
 static void free_stats_record(struct stats_record *r)
 {
-       unsigned int nr_rxqs = map_data[2].def.max_entries;
+       unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
        int i;
 
        for (i = 0; i < nr_rxqs; i++)
@@ -254,11 +257,11 @@ static void stats_collect(struct stats_record *rec)
 {
        int fd, i, max_rxqs;
 
-       fd = map_data[1].fd; /* map: stats_global_map */
+       fd = bpf_map__fd(stats_global_map);
        map_collect_percpu(fd, 0, &rec->stats);
 
-       fd = map_data[2].fd; /* map: rx_queue_index_map */
-       max_rxqs = map_data[2].def.max_entries;
+       fd = bpf_map__fd(rx_queue_index_map);
+       max_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
        for (i = 0; i < max_rxqs; i++)
                map_collect_percpu(fd, i, &rec->rxq[i]);
 }
@@ -304,8 +307,8 @@ static void stats_print(struct stats_record *stats_rec,
                        struct stats_record *stats_prev,
                        int action)
 {
+       unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries;
        unsigned int nr_cpus = bpf_num_possible_cpus();
-       unsigned int nr_rxqs = map_data[2].def.max_entries;
        double pps = 0, err = 0;
        struct record *rec, *prev;
        double t;
@@ -419,31 +422,44 @@ static void stats_poll(int interval, int action)
 int main(int argc, char **argv)
 {
        struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
+       struct bpf_prog_load_attr prog_load_attr = {
+               .prog_type      = BPF_PROG_TYPE_XDP,
+       };
+       int prog_fd, map_fd, opt, err;
        bool use_separators = true;
        struct config cfg = { 0 };
+       struct bpf_object *obj;
+       struct bpf_map *map;
        char filename[256];
        int longindex = 0;
        int interval = 2;
        __u32 key = 0;
-       int opt, err;
 
        char action_str_buf[XDP_ACTION_MAX_STRLEN + 1 /* for \0 */] = { 0 };
        int action = XDP_PASS; /* Default action */
        char *action_str = NULL;
 
        snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+       prog_load_attr.file = filename;
 
        if (setrlimit(RLIMIT_MEMLOCK, &r)) {
                perror("setrlimit(RLIMIT_MEMLOCK)");
                return 1;
        }
 
-       if (load_bpf_file(filename)) {
-               fprintf(stderr, "ERR in load_bpf_file(): %s", bpf_log_buf);
+       if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
+               return EXIT_FAIL;
+
+       map = bpf_map__next(NULL, obj);
+       stats_global_map = bpf_map__next(map, obj);
+       rx_queue_index_map = bpf_map__next(stats_global_map, obj);
+       if (!map || !stats_global_map || !rx_queue_index_map) {
+               printf("finding a map in obj file failed\n");
                return EXIT_FAIL;
        }
+       map_fd = bpf_map__fd(map);
 
-       if (!prog_fd[0]) {
+       if (!prog_fd) {
                fprintf(stderr, "ERR: load_bpf_file: %s\n", strerror(errno));
                return EXIT_FAIL;
        }
@@ -512,7 +528,7 @@ int main(int argc, char **argv)
                setlocale(LC_NUMERIC, "en_US");
 
        /* User-side setup ifindex in config_map */
-       err = bpf_map_update_elem(map_fd[0], &key, &cfg, 0);
+       err = bpf_map_update_elem(map_fd, &key, &cfg, 0);
        if (err) {
                fprintf(stderr, "Store config failed (err:%d)\n", err);
                exit(EXIT_FAIL_BPF);
@@ -521,7 +537,7 @@ int main(int argc, char **argv)
        /* Remove XDP program when program is interrupted */
        signal(SIGINT, int_exit);
 
-       if (bpf_set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
+       if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
                fprintf(stderr, "link set xdp fd failed\n");
                return EXIT_FAIL_XDP;
        }