samples/bpf/xdp_redirect_cpu_user.c

   1 /* GPLv2 Copyright(c) 2017 Jesper Dangaard Brouer, Red Hat, Inc.
   2  */
   3 static const char *__doc__ =
   4         " XDP redirect with a CPU-map type \"BPF_MAP_TYPE_CPUMAP\"";
   5
   6 #include <errno.h>
   7 #include <signal.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <stdbool.h>
  11 #include <string.h>
  12 #include <unistd.h>
  13 #include <locale.h>
  14 #include <sys/resource.h>
  15 #include <getopt.h>
  16 #include <net/if.h>
  17 #include <time.h>
  18
  19 #include <arpa/inet.h>
  20 #include <linux/if_link.h>
  21
  22 #define MAX_CPUS 12 /* WARNING - sync with _kern.c */
  23
  24 /* How many xdp_progs are defined in _kern.c */
  25 #define MAX_PROG 5
  26
  27 /* Wanted to get rid of bpf_load.h and fake-"libbpf.h" (and instead
  28  * use bpf/libbpf.h), but cannot as (currently) needed for XDP
  29  * attaching to a device via set_link_xdp_fd()
  30  */
  31 #include "libbpf.h"
  32 #include "bpf_load.h"
  33
  34 #include "bpf_util.h"
  35
  36 static int ifindex = -1;
  37 static char ifname_buf[IF_NAMESIZE];
  38 static char *ifname;
  39
  40 static __u32 xdp_flags;
  41
  42 /* Exit return codes */
  43 #define EXIT_OK         0
  44 #define EXIT_FAIL               1
  45 #define EXIT_FAIL_OPTION        2
  46 #define EXIT_FAIL_XDP           3
  47 #define EXIT_FAIL_BPF           4
  48 #define EXIT_FAIL_MEM           5
  49
  50 static const struct option long_options[] = {
  51         {"help",        no_argument,            NULL, 'h' },
  52         {"dev",         required_argument,      NULL, 'd' },
  53         {"skb-mode",    no_argument,            NULL, 'S' },
  54         {"debug",       no_argument,            NULL, 'D' },
  55         {"sec",         required_argument,      NULL, 's' },
  56         {"prognum",     required_argument,      NULL, 'p' },
  57         {"qsize",       required_argument,      NULL, 'q' },
  58         {"cpu",         required_argument,      NULL, 'c' },
  59         {"stress-mode", no_argument,            NULL, 'x' },
  60         {"no-separators", no_argument,          NULL, 'z' },
  61         {0, 0, NULL,  0 }
  62 };
  63
  64 static void int_exit(int sig)
  65 {
  66         fprintf(stderr,
  67                 "Interrupted: Removing XDP program on ifindex:%d device:%s\n",
  68                 ifindex, ifname);
  69         if (ifindex > -1)
  70                 set_link_xdp_fd(ifindex, -1, xdp_flags);
  71         exit(EXIT_OK);
  72 }
  73
  74 static void usage(char *argv[])
  75 {
  76         int i;
  77
  78         printf("\nDOCUMENTATION:\n%s\n", __doc__);
  79         printf("\n");
  80         printf(" Usage: %s (options-see-below)\n", argv[0]);
  81         printf(" Listing options:\n");
  82         for (i = 0; long_options[i].name != 0; i++) {
  83                 printf(" --%-12s", long_options[i].name);
  84                 if (long_options[i].flag != NULL)
  85                         printf(" flag (internal value:%d)",
  86                                 *long_options[i].flag);
  87                 else
  88                         printf(" short-option: -%c",
  89                                 long_options[i].val);
  90                 printf("\n");
  91         }
  92         printf("\n");
  93 }
  94
  95 /* gettime returns the current time of day in nanoseconds.
  96  * Cost: clock_gettime (ns) => 26ns (CLOCK_MONOTONIC)
  97  *       clock_gettime (ns) =>  9ns (CLOCK_MONOTONIC_COARSE)
  98  */
  99 #define NANOSEC_PER_SEC 1000000000 /* 10^9 */
 100 static __u64 gettime(void)
 101 {
 102         struct timespec t;
 103         int res;
 104
 105         res = clock_gettime(CLOCK_MONOTONIC, &t);
 106         if (res < 0) {
 107                 fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
 108                 exit(EXIT_FAIL);
 109         }
 110         return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
 111 }
 112
 113 /* Common stats data record shared with _kern.c */
 114 struct datarec {
 115         __u64 processed;
 116         __u64 dropped;
 117         __u64 issue;
 118 };
 119 struct record {
 120         __u64 timestamp;
 121         struct datarec total;
 122         struct datarec *cpu;
 123 };
 124 struct stats_record {
 125         struct record rx_cnt;
 126         struct record redir_err;
 127         struct record kthread;
 128         struct record exception;
 129         struct record enq[MAX_CPUS];
 130 };
 131
 132 static bool map_collect_percpu(int fd, __u32 key, struct record *rec)
 133 {
 134         /* For percpu maps, userspace gets a value per possible CPU */
 135         unsigned int nr_cpus = bpf_num_possible_cpus();
 136         struct datarec values[nr_cpus];
 137         __u64 sum_processed = 0;
 138         __u64 sum_dropped = 0;
 139         __u64 sum_issue = 0;
 140         int i;
 141
 142         if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
 143                 fprintf(stderr,
 144                         "ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
 145                 return false;
 146         }
 147         /* Get time as close as possible to reading map contents */
 148         rec->timestamp = gettime();
 149
 150         /* Record and sum values from each CPU */
 151         for (i = 0; i < nr_cpus; i++) {
 152                 rec->cpu[i].processed = values[i].processed;
 153                 sum_processed        += values[i].processed;
 154                 rec->cpu[i].dropped = values[i].dropped;
 155                 sum_dropped        += values[i].dropped;
 156                 rec->cpu[i].issue = values[i].issue;
 157                 sum_issue        += values[i].issue;
 158         }
 159         rec->total.processed = sum_processed;
 160         rec->total.dropped   = sum_dropped;
 161         rec->total.issue     = sum_issue;
 162         return true;
 163 }
 164
 165 static struct datarec *alloc_record_per_cpu(void)
 166 {
 167         unsigned int nr_cpus = bpf_num_possible_cpus();
 168         struct datarec *array;
 169         size_t size;
 170
 171         size = sizeof(struct datarec) * nr_cpus;
 172         array = malloc(size);
 173         memset(array, 0, size);
 174         if (!array) {
 175                 fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
 176                 exit(EXIT_FAIL_MEM);
 177         }
 178         return array;
 179 }
 180
 181 static struct stats_record *alloc_stats_record(void)
 182 {
 183         struct stats_record *rec;
 184         int i;
 185
 186         rec = malloc(sizeof(*rec));
 187         memset(rec, 0, sizeof(*rec));
 188         if (!rec) {
 189                 fprintf(stderr, "Mem alloc error\n");
 190                 exit(EXIT_FAIL_MEM);
 191         }
 192         rec->rx_cnt.cpu    = alloc_record_per_cpu();
 193         rec->redir_err.cpu = alloc_record_per_cpu();
 194         rec->kthread.cpu   = alloc_record_per_cpu();
 195         rec->exception.cpu = alloc_record_per_cpu();
 196         for (i = 0; i < MAX_CPUS; i++)
 197                 rec->enq[i].cpu = alloc_record_per_cpu();
 198
 199         return rec;
 200 }
 201
 202 static void free_stats_record(struct stats_record *r)
 203 {
 204         int i;
 205
 206         for (i = 0; i < MAX_CPUS; i++)
 207                 free(r->enq[i].cpu);
 208         free(r->exception.cpu);
 209         free(r->kthread.cpu);
 210         free(r->redir_err.cpu);
 211         free(r->rx_cnt.cpu);
 212         free(r);
 213 }
 214
 215 static double calc_period(struct record *r, struct record *p)
 216 {
 217         double period_ = 0;
 218         __u64 period = 0;
 219
 220         period = r->timestamp - p->timestamp;
 221         if (period > 0)
 222                 period_ = ((double) period / NANOSEC_PER_SEC);
 223
 224         return period_;
 225 }
 226
 227 static __u64 calc_pps(struct datarec *r, struct datarec *p, double period_)
 228 {
 229         __u64 packets = 0;
 230         __u64 pps = 0;
 231
 232         if (period_ > 0) {
 233                 packets = r->processed - p->processed;
 234                 pps = packets / period_;
 235         }
 236         return pps;
 237 }
 238
 239 static __u64 calc_drop_pps(struct datarec *r, struct datarec *p, double period_)
 240 {
 241         __u64 packets = 0;
 242         __u64 pps = 0;
 243
 244         if (period_ > 0) {
 245                 packets = r->dropped - p->dropped;
 246                 pps = packets / period_;
 247         }
 248         return pps;
 249 }
 250
 251 static __u64 calc_errs_pps(struct datarec *r,
 252                             struct datarec *p, double period_)
 253 {
 254         __u64 packets = 0;
 255         __u64 pps = 0;
 256
 257         if (period_ > 0) {
 258                 packets = r->issue - p->issue;
 259                 pps = packets / period_;
 260         }
 261         return pps;
 262 }
 263
 264 static void stats_print(struct stats_record *stats_rec,
 265                         struct stats_record *stats_prev,
 266                         int prog_num)
 267 {
 268         unsigned int nr_cpus = bpf_num_possible_cpus();
 269         double pps = 0, drop = 0, err = 0;
 270         struct record *rec, *prev;
 271         int to_cpu;
 272         double t;
 273         int i;
 274
 275         /* Header */
 276         printf("Running XDP/eBPF prog_num:%d\n", prog_num);
 277         printf("%-15s %-7s %-14s %-11s %-9s\n",
 278                "XDP-cpumap", "CPU:to", "pps", "drop-pps", "extra-info");
 279
 280         /* XDP rx_cnt */
 281         {
 282                 char *fmt_rx = "%-15s %-7d %'-14.0f %'-11.0f %'-10.0f %s\n";
 283                 char *fm2_rx = "%-15s %-7s %'-14.0f %'-11.0f\n";
 284                 char *errstr = "";
 285
 286                 rec  = &stats_rec->rx_cnt;
 287                 prev = &stats_prev->rx_cnt;
 288                 t = calc_period(rec, prev);
 289                 for (i = 0; i < nr_cpus; i++) {
 290                         struct datarec *r = &rec->cpu[i];
 291                         struct datarec *p = &prev->cpu[i];
 292
 293                         pps = calc_pps(r, p, t);
 294                         drop = calc_drop_pps(r, p, t);
 295                         err  = calc_errs_pps(r, p, t);
 296                         if (err > 0)
 297                                 errstr = "cpu-dest/err";
 298                         if (pps > 0)
 299                                 printf(fmt_rx, "XDP-RX",
 300                                         i, pps, drop, err, errstr);
 301                 }
 302                 pps  = calc_pps(&rec->total, &prev->total, t);
 303                 drop = calc_drop_pps(&rec->total, &prev->total, t);
 304                 err  = calc_errs_pps(&rec->total, &prev->total, t);
 305                 printf(fm2_rx, "XDP-RX", "total", pps, drop);
 306         }
 307
 308         /* cpumap enqueue stats */
 309         for (to_cpu = 0; to_cpu < MAX_CPUS; to_cpu++) {
 310                 char *fmt = "%-15s %3d:%-3d %'-14.0f %'-11.0f %'-10.2f %s\n";
 311                 char *fm2 = "%-15s %3s:%-3d %'-14.0f %'-11.0f %'-10.2f %s\n";
 312                 char *errstr = "";
 313
 314                 rec  =  &stats_rec->enq[to_cpu];
 315                 prev = &stats_prev->enq[to_cpu];
 316                 t = calc_period(rec, prev);
 317                 for (i = 0; i < nr_cpus; i++) {
 318                         struct datarec *r = &rec->cpu[i];
 319                         struct datarec *p = &prev->cpu[i];
 320
 321                         pps  = calc_pps(r, p, t);
 322                         drop = calc_drop_pps(r, p, t);
 323                         err  = calc_errs_pps(r, p, t);
 324                         if (err > 0) {
 325                                 errstr = "bulk-average";
 326                                 err = pps / err; /* calc average bulk size */
 327                         }
 328                         if (pps > 0)
 329                                 printf(fmt, "cpumap-enqueue",
 330                                        i, to_cpu, pps, drop, err, errstr);
 331                 }
 332                 pps = calc_pps(&rec->total, &prev->total, t);
 333                 if (pps > 0) {
 334                         drop = calc_drop_pps(&rec->total, &prev->total, t);
 335                         err  = calc_errs_pps(&rec->total, &prev->total, t);
 336                         if (err > 0) {
 337                                 errstr = "bulk-average";
 338                                 err = pps / err; /* calc average bulk size */
 339                         }
 340                         printf(fm2, "cpumap-enqueue",
 341                                "sum", to_cpu, pps, drop, err, errstr);
 342                 }
 343         }
 344
 345         /* cpumap kthread stats */
 346         {
 347                 char *fmt_k = "%-15s %-7d %'-14.0f %'-11.0f %'-10.0f %s\n";
 348                 char *fm2_k = "%-15s %-7s %'-14.0f %'-11.0f %'-10.0f %s\n";
 349                 char *e_str = "";
 350
 351                 rec  = &stats_rec->kthread;
 352                 prev = &stats_prev->kthread;
 353                 t = calc_period(rec, prev);
 354                 for (i = 0; i < nr_cpus; i++) {
 355                         struct datarec *r = &rec->cpu[i];
 356                         struct datarec *p = &prev->cpu[i];
 357
 358                         pps  = calc_pps(r, p, t);
 359                         drop = calc_drop_pps(r, p, t);
 360                         err  = calc_errs_pps(r, p, t);
 361                         if (err > 0)
 362                                 e_str = "sched";
 363                         if (pps > 0)
 364                                 printf(fmt_k, "cpumap_kthread",
 365                                        i, pps, drop, err, e_str);
 366                 }
 367                 pps = calc_pps(&rec->total, &prev->total, t);
 368                 drop = calc_drop_pps(&rec->total, &prev->total, t);
 369                 err  = calc_errs_pps(&rec->total, &prev->total, t);
 370                 if (err > 0)
 371                         e_str = "sched-sum";
 372                 printf(fm2_k, "cpumap_kthread", "total", pps, drop, err, e_str);
 373         }
 374
 375         /* XDP redirect err tracepoints (very unlikely) */
 376         {
 377                 char *fmt_err = "%-15s %-7d %'-14.0f %'-11.0f\n";
 378                 char *fm2_err = "%-15s %-7s %'-14.0f %'-11.0f\n";
 379
 380                 rec  = &stats_rec->redir_err;
 381                 prev = &stats_prev->redir_err;
 382                 t = calc_period(rec, prev);
 383                 for (i = 0; i < nr_cpus; i++) {
 384                         struct datarec *r = &rec->cpu[i];
 385                         struct datarec *p = &prev->cpu[i];
 386
 387                         pps  = calc_pps(r, p, t);
 388                         drop = calc_drop_pps(r, p, t);
 389                         if (pps > 0)
 390                                 printf(fmt_err, "redirect_err", i, pps, drop);
 391                 }
 392                 pps = calc_pps(&rec->total, &prev->total, t);
 393                 drop = calc_drop_pps(&rec->total, &prev->total, t);
 394                 printf(fm2_err, "redirect_err", "total", pps, drop);
 395         }
 396
 397         /* XDP general exception tracepoints */
 398         {
 399                 char *fmt_err = "%-15s %-7d %'-14.0f %'-11.0f\n";
 400                 char *fm2_err = "%-15s %-7s %'-14.0f %'-11.0f\n";
 401
 402                 rec  = &stats_rec->exception;
 403                 prev = &stats_prev->exception;
 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                         drop = calc_drop_pps(r, p, t);
 411                         if (pps > 0)
 412                                 printf(fmt_err, "xdp_exception", i, pps, drop);
 413                 }
 414                 pps = calc_pps(&rec->total, &prev->total, t);
 415                 drop = calc_drop_pps(&rec->total, &prev->total, t);
 416                 printf(fm2_err, "xdp_exception", "total", pps, drop);
 417         }
 418
 419         printf("\n");
 420         fflush(stdout);
 421 }
 422
 423 static void stats_collect(struct stats_record *rec)
 424 {
 425         int fd, i;
 426
 427         fd = map_fd[1]; /* map: rx_cnt */
 428         map_collect_percpu(fd, 0, &rec->rx_cnt);
 429
 430         fd = map_fd[2]; /* map: redirect_err_cnt */
 431         map_collect_percpu(fd, 1, &rec->redir_err);
 432
 433         fd = map_fd[3]; /* map: cpumap_enqueue_cnt */
 434         for (i = 0; i < MAX_CPUS; i++)
 435                 map_collect_percpu(fd, i, &rec->enq[i]);
 436
 437         fd = map_fd[4]; /* map: cpumap_kthread_cnt */
 438         map_collect_percpu(fd, 0, &rec->kthread);
 439
 440         fd = map_fd[8]; /* map: exception_cnt */
 441         map_collect_percpu(fd, 0, &rec->exception);
 442 }
 443
 444
 445 /* Pointer swap trick */
 446 static inline void swap(struct stats_record **a, struct stats_record **b)
 447 {
 448         struct stats_record *tmp;
 449
 450         tmp = *a;
 451         *a = *b;
 452         *b = tmp;
 453 }
 454
 455 static int create_cpu_entry(__u32 cpu, __u32 queue_size,
 456                             __u32 avail_idx, bool new)
 457 {
 458         __u32 curr_cpus_count = 0;
 459         __u32 key = 0;
 460         int ret;
 461
 462         /* Add a CPU entry to cpumap, as this allocate a cpu entry in
 463          * the kernel for the cpu.
 464          */
 465         ret = bpf_map_update_elem(map_fd[0], &cpu, &queue_size, 0);
 466         if (ret) {
 467                 fprintf(stderr, "Create CPU entry failed (err:%d)\n", ret);
 468                 exit(EXIT_FAIL_BPF);
 469         }
 470
 471         /* Inform bpf_prog's that a new CPU is available to select
 472          * from via some control maps.
 473          */
 474         /* map_fd[5] = cpus_available */
 475         ret = bpf_map_update_elem(map_fd[5], &avail_idx, &cpu, 0);
 476         if (ret) {
 477                 fprintf(stderr, "Add to avail CPUs failed\n");
 478                 exit(EXIT_FAIL_BPF);
 479         }
 480
 481         /* When not replacing/updating existing entry, bump the count */
 482         /* map_fd[6] = cpus_count */
 483         ret = bpf_map_lookup_elem(map_fd[6], &key, &curr_cpus_count);
 484         if (ret) {
 485                 fprintf(stderr, "Failed reading curr cpus_count\n");
 486                 exit(EXIT_FAIL_BPF);
 487         }
 488         if (new) {
 489                 curr_cpus_count++;
 490                 ret = bpf_map_update_elem(map_fd[6], &key, &curr_cpus_count, 0);
 491                 if (ret) {
 492                         fprintf(stderr, "Failed write curr cpus_count\n");
 493                         exit(EXIT_FAIL_BPF);
 494                 }
 495         }
 496         /* map_fd[7] = cpus_iterator */
 497         printf("%s CPU:%u as idx:%u queue_size:%d (total cpus_count:%u)\n",
 498                new ? "Add-new":"Replace", cpu, avail_idx,
 499                queue_size, curr_cpus_count);
 500
 501         return 0;
 502 }
 503
 504 /* CPUs are zero-indexed. Thus, add a special sentinel default value
 505  * in map cpus_available to mark CPU index'es not configured
 506  */
 507 static void mark_cpus_unavailable(void)
 508 {
 509         __u32 invalid_cpu = MAX_CPUS;
 510         int ret, i;
 511
 512         for (i = 0; i < MAX_CPUS; i++) {
 513                 /* map_fd[5] = cpus_available */
 514                 ret = bpf_map_update_elem(map_fd[5], &i, &invalid_cpu, 0);
 515                 if (ret) {
 516                         fprintf(stderr, "Failed marking CPU unavailable\n");
 517                         exit(EXIT_FAIL_BPF);
 518                 }
 519         }
 520 }
 521
 522 /* Stress cpumap management code by concurrently changing underlying cpumap */
 523 static void stress_cpumap(void)
 524 {
 525         /* Changing qsize will cause kernel to free and alloc a new
 526          * bpf_cpu_map_entry, with an associated/complicated tear-down
 527          * procedure.
 528          */
 529         create_cpu_entry(1,  1024, 0, false);
 530         create_cpu_entry(1,   128, 0, false);
 531         create_cpu_entry(1, 16000, 0, false);
 532 }
 533
 534 static void stats_poll(int interval, bool use_separators, int prog_num,
 535                        bool stress_mode)
 536 {
 537         struct stats_record *record, *prev;
 538
 539         record = alloc_stats_record();
 540         prev   = alloc_stats_record();
 541         stats_collect(record);
 542
 543         /* Trick to pretty printf with thousands separators use %' */
 544         if (use_separators)
 545                 setlocale(LC_NUMERIC, "en_US");
 546
 547         while (1) {
 548                 swap(&prev, &record);
 549                 stats_collect(record);
 550                 stats_print(record, prev, prog_num);
 551                 sleep(interval);
 552                 if (stress_mode)
 553                         stress_cpumap();
 554         }
 555
 556         free_stats_record(record);
 557         free_stats_record(prev);
 558 }
 559
 560 int main(int argc, char **argv)
 561 {
 562         struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
 563         bool use_separators = true;
 564         bool stress_mode = false;
 565         char filename[256];
 566         bool debug = false;
 567         int added_cpus = 0;
 568         int longindex = 0;
 569         int interval = 2;
 570         int prog_num = 0;
 571         int add_cpu = -1;
 572         __u32 qsize;
 573         int opt;
 574
 575         /* Notice: choosing he queue size is very important with the
 576          * ixgbe driver, because it's driver page recycling trick is
 577          * dependend on pages being returned quickly.  The number of
 578          * out-standing packets in the system must be less-than 2x
 579          * RX-ring size.
 580          */
 581         qsize = 128+64;
 582
 583         snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 584
 585         if (setrlimit(RLIMIT_MEMLOCK, &r)) {
 586                 perror("setrlimit(RLIMIT_MEMLOCK)");
 587                 return 1;
 588         }
 589
 590         if (load_bpf_file(filename)) {
 591                 fprintf(stderr, "ERR in load_bpf_file(): %s", bpf_log_buf);
 592                 return EXIT_FAIL;
 593         }
 594
 595         if (!prog_fd[0]) {
 596                 fprintf(stderr, "ERR: load_bpf_file: %s\n", strerror(errno));
 597                 return EXIT_FAIL;
 598         }
 599
 600         mark_cpus_unavailable();
 601
 602         /* Parse commands line args */
 603         while ((opt = getopt_long(argc, argv, "hSd:",
 604                                   long_options, &longindex)) != -1) {
 605                 switch (opt) {
 606                 case 'd':
 607                         if (strlen(optarg) >= IF_NAMESIZE) {
 608                                 fprintf(stderr, "ERR: --dev name too long\n");
 609                                 goto error;
 610                         }
 611                         ifname = (char *)&ifname_buf;
 612                         strncpy(ifname, optarg, IF_NAMESIZE);
 613                         ifindex = if_nametoindex(ifname);
 614                         if (ifindex == 0) {
 615                                 fprintf(stderr,
 616                                         "ERR: --dev name unknown err(%d):%s\n",
 617                                         errno, strerror(errno));
 618                                 goto error;
 619                         }
 620                         break;
 621                 case 's':
 622                         interval = atoi(optarg);
 623                         break;
 624                 case 'S':
 625                         xdp_flags |= XDP_FLAGS_SKB_MODE;
 626                         break;
 627                 case 'D':
 628                         debug = true;
 629                         break;
 630                 case 'x':
 631                         stress_mode = true;
 632                         break;
 633                 case 'z':
 634                         use_separators = false;
 635                         break;
 636                 case 'p':
 637                         /* Selecting eBPF prog to load */
 638                         prog_num = atoi(optarg);
 639                         if (prog_num < 0 || prog_num >= MAX_PROG) {
 640                                 fprintf(stderr,
 641                                         "--prognum too large err(%d):%s\n",
 642                                         errno, strerror(errno));
 643                                 goto error;
 644                         }
 645                         break;
 646                 case 'c':
 647                         /* Add multiple CPUs */
 648                         add_cpu = strtoul(optarg, NULL, 0);
 649                         if (add_cpu >= MAX_CPUS) {
 650                                 fprintf(stderr,
 651                                 "--cpu nr too large for cpumap err(%d):%s\n",
 652                                         errno, strerror(errno));
 653                                 goto error;
 654                         }
 655                         create_cpu_entry(add_cpu, qsize, added_cpus, true);
 656                         added_cpus++;
 657                         break;
 658                 case 'q':
 659                         qsize = atoi(optarg);
 660                         break;
 661                 case 'h':
 662                 error:
 663                 default:
 664                         usage(argv);
 665                         return EXIT_FAIL_OPTION;
 666                 }
 667         }
 668         /* Required option */
 669         if (ifindex == -1) {
 670                 fprintf(stderr, "ERR: required option --dev missing\n");
 671                 usage(argv);
 672                 return EXIT_FAIL_OPTION;
 673         }
 674         /* Required option */
 675         if (add_cpu == -1) {
 676                 fprintf(stderr, "ERR: required option --cpu missing\n");
 677                 fprintf(stderr, " Specify multiple --cpu option to add more\n");
 678                 usage(argv);
 679                 return EXIT_FAIL_OPTION;
 680         }
 681
 682         /* Remove XDP program when program is interrupted */
 683         signal(SIGINT, int_exit);
 684
 685         if (set_link_xdp_fd(ifindex, prog_fd[prog_num], xdp_flags) < 0) {
 686                 fprintf(stderr, "link set xdp fd failed\n");
 687                 return EXIT_FAIL_XDP;
 688         }
 689
 690         if (debug) {
 691                 printf("Debug-mode reading trace pipe (fix #define DEBUG)\n");
 692                 read_trace_pipe();
 693         }
 694
 695         stats_poll(interval, use_separators, prog_num, stress_mode);
 696         return EXIT_OK;
 697 }