app/test-pmd/txonly.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation
   3  */
   4
   5 #include <stdarg.h>
   6 #include <string.h>
   7 #include <stdio.h>
   8 #include <errno.h>
   9 #include <stdint.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12
  13 #include <sys/queue.h>
  14 #include <sys/stat.h>
  15
  16 #include <rte_common.h>
  17 #include <rte_byteorder.h>
  18 #include <rte_log.h>
  19 #include <rte_debug.h>
  20 #include <rte_cycles.h>
  21 #include <rte_memory.h>
  22 #include <rte_memcpy.h>
  23 #include <rte_launch.h>
  24 #include <rte_eal.h>
  25 #include <rte_per_lcore.h>
  26 #include <rte_lcore.h>
  27 #include <rte_branch_prediction.h>
  28 #include <rte_mempool.h>
  29 #include <rte_mbuf.h>
  30 #include <rte_interrupts.h>
  31 #include <rte_pci.h>
  32 #include <rte_ether.h>
  33 #include <rte_ethdev.h>
  34 #include <rte_ip.h>
  35 #include <rte_tcp.h>
  36 #include <rte_udp.h>
  37 #include <rte_string_fns.h>
  38 #include <rte_flow.h>
  39
  40 #include "testpmd.h"
  41
  42 struct tx_timestamp {
  43         rte_be32_t signature;
  44         rte_be16_t pkt_idx;
  45         rte_be16_t queue_idx;
  46         rte_be64_t ts;
  47 };
  48
  49 /* use RFC863 Discard Protocol */
  50 uint16_t tx_udp_src_port = 9;
  51 uint16_t tx_udp_dst_port = 9;
  52
  53 /* use RFC5735 / RFC2544 reserved network test addresses */
  54 uint32_t tx_ip_src_addr = (198U << 24) | (18 << 16) | (0 << 8) | 1;
  55 uint32_t tx_ip_dst_addr = (198U << 24) | (18 << 16) | (0 << 8) | 2;
  56
  57 #define IP_DEFTTL  64   /* from RFC 1340. */
  58
  59 static struct rte_ipv4_hdr pkt_ip_hdr; /**< IP header of transmitted packets. */
  60 RTE_DEFINE_PER_LCORE(uint8_t, _ip_var); /**< IP address variation */
  61 static struct rte_udp_hdr pkt_udp_hdr; /**< UDP header of tx packets. */
  62 RTE_DEFINE_PER_LCORE(uint64_t, timestamp_qskew);
  63                                         /**< Timestamp offset per queue */
  64 RTE_DEFINE_PER_LCORE(uint32_t, timestamp_idone); /**< Timestamp init done. */
  65
  66 static uint64_t timestamp_mask; /**< Timestamp dynamic flag mask */
  67 static int32_t timestamp_off; /**< Timestamp dynamic field offset */
  68 static bool timestamp_enable; /**< Timestamp enable */
  69 static uint32_t timestamp_init_req; /**< Timestamp initialization request. */
  70 static uint64_t timestamp_initial[RTE_MAX_ETHPORTS];
  71
  72 static void
  73 copy_buf_to_pkt_segs(void* buf, unsigned len, struct rte_mbuf *pkt,
  74                      unsigned offset)
  75 {
  76         struct rte_mbuf *seg;
  77         void *seg_buf;
  78         unsigned copy_len;
  79
  80         seg = pkt;
  81         while (offset >= seg->data_len) {
  82                 offset -= seg->data_len;
  83                 seg = seg->next;
  84         }
  85         copy_len = seg->data_len - offset;
  86         seg_buf = rte_pktmbuf_mtod_offset(seg, char *, offset);
  87         while (len > copy_len) {
  88                 rte_memcpy(seg_buf, buf, (size_t) copy_len);
  89                 len -= copy_len;
  90                 buf = ((char*) buf + copy_len);
  91                 seg = seg->next;
  92                 seg_buf = rte_pktmbuf_mtod(seg, char *);
  93                 copy_len = seg->data_len;
  94         }
  95         rte_memcpy(seg_buf, buf, (size_t) len);
  96 }
  97
  98 static inline void
  99 copy_buf_to_pkt(void* buf, unsigned len, struct rte_mbuf *pkt, unsigned offset)
 100 {
 101         if (offset + len <= pkt->data_len) {
 102                 rte_memcpy(rte_pktmbuf_mtod_offset(pkt, char *, offset),
 103                         buf, (size_t) len);
 104                 return;
 105         }
 106         copy_buf_to_pkt_segs(buf, len, pkt, offset);
 107 }
 108
 109 static void
 110 setup_pkt_udp_ip_headers(struct rte_ipv4_hdr *ip_hdr,
 111                          struct rte_udp_hdr *udp_hdr,
 112                          uint16_t pkt_data_len)
 113 {
 114         uint16_t *ptr16;
 115         uint32_t ip_cksum;
 116         uint16_t pkt_len;
 117
 118         /*
 119          * Initialize UDP header.
 120          */
 121         pkt_len = (uint16_t) (pkt_data_len + sizeof(struct rte_udp_hdr));
 122         udp_hdr->src_port = rte_cpu_to_be_16(tx_udp_src_port);
 123         udp_hdr->dst_port = rte_cpu_to_be_16(tx_udp_dst_port);
 124         udp_hdr->dgram_len      = RTE_CPU_TO_BE_16(pkt_len);
 125         udp_hdr->dgram_cksum    = 0; /* No UDP checksum. */
 126
 127         /*
 128          * Initialize IP header.
 129          */
 130         pkt_len = (uint16_t) (pkt_len + sizeof(struct rte_ipv4_hdr));
 131         ip_hdr->version_ihl   = RTE_IPV4_VHL_DEF;
 132         ip_hdr->type_of_service   = 0;
 133         ip_hdr->fragment_offset = 0;
 134         ip_hdr->time_to_live   = IP_DEFTTL;
 135         ip_hdr->next_proto_id = IPPROTO_UDP;
 136         ip_hdr->packet_id = 0;
 137         ip_hdr->total_length   = RTE_CPU_TO_BE_16(pkt_len);
 138         ip_hdr->src_addr = rte_cpu_to_be_32(tx_ip_src_addr);
 139         ip_hdr->dst_addr = rte_cpu_to_be_32(tx_ip_dst_addr);
 140
 141         /*
 142          * Compute IP header checksum.
 143          */
 144         ptr16 = (unaligned_uint16_t*) ip_hdr;
 145         ip_cksum = 0;
 146         ip_cksum += ptr16[0]; ip_cksum += ptr16[1];
 147         ip_cksum += ptr16[2]; ip_cksum += ptr16[3];
 148         ip_cksum += ptr16[4];
 149         ip_cksum += ptr16[6]; ip_cksum += ptr16[7];
 150         ip_cksum += ptr16[8]; ip_cksum += ptr16[9];
 151
 152         /*
 153          * Reduce 32 bit checksum to 16 bits and complement it.
 154          */
 155         ip_cksum = ((ip_cksum & 0xFFFF0000) >> 16) +
 156                 (ip_cksum & 0x0000FFFF);
 157         if (ip_cksum > 65535)
 158                 ip_cksum -= 65535;
 159         ip_cksum = (~ip_cksum) & 0x0000FFFF;
 160         if (ip_cksum == 0)
 161                 ip_cksum = 0xFFFF;
 162         ip_hdr->hdr_checksum = (uint16_t) ip_cksum;
 163 }
 164
 165 static inline void
 166 update_pkt_header(struct rte_mbuf *pkt, uint32_t total_pkt_len)
 167 {
 168         struct rte_ipv4_hdr *ip_hdr;
 169         struct rte_udp_hdr *udp_hdr;
 170         uint16_t pkt_data_len;
 171         uint16_t pkt_len;
 172
 173         pkt_data_len = (uint16_t) (total_pkt_len - (
 174                                         sizeof(struct rte_ether_hdr) +
 175                                         sizeof(struct rte_ipv4_hdr) +
 176                                         sizeof(struct rte_udp_hdr)));
 177         /* update UDP packet length */
 178         udp_hdr = rte_pktmbuf_mtod_offset(pkt, struct rte_udp_hdr *,
 179                                 sizeof(struct rte_ether_hdr) +
 180                                 sizeof(struct rte_ipv4_hdr));
 181         pkt_len = (uint16_t) (pkt_data_len + sizeof(struct rte_udp_hdr));
 182         udp_hdr->dgram_len = RTE_CPU_TO_BE_16(pkt_len);
 183
 184         /* update IP packet length and checksum */
 185         ip_hdr = rte_pktmbuf_mtod_offset(pkt, struct rte_ipv4_hdr *,
 186                                 sizeof(struct rte_ether_hdr));
 187         ip_hdr->hdr_checksum = 0;
 188         pkt_len = (uint16_t) (pkt_len + sizeof(struct rte_ipv4_hdr));
 189         ip_hdr->total_length = RTE_CPU_TO_BE_16(pkt_len);
 190         ip_hdr->hdr_checksum = rte_ipv4_cksum(ip_hdr);
 191 }
 192
 193 static inline bool
 194 pkt_burst_prepare(struct rte_mbuf *pkt, struct rte_mempool *mbp,
 195                 struct rte_ether_hdr *eth_hdr, const uint16_t vlan_tci,
 196                 const uint16_t vlan_tci_outer, const uint64_t ol_flags,
 197                 const uint16_t idx, const struct fwd_stream *fs)
 198 {
 199         struct rte_mbuf *pkt_segs[RTE_MAX_SEGS_PER_PKT];
 200         struct rte_mbuf *pkt_seg;
 201         uint32_t nb_segs, pkt_len;
 202         uint8_t i;
 203
 204         if (unlikely(tx_pkt_split == TX_PKT_SPLIT_RND))
 205                 nb_segs = rte_rand() % tx_pkt_nb_segs + 1;
 206         else
 207                 nb_segs = tx_pkt_nb_segs;
 208
 209         if (nb_segs > 1) {
 210                 if (rte_mempool_get_bulk(mbp, (void **)pkt_segs, nb_segs - 1))
 211                         return false;
 212         }
 213
 214         rte_pktmbuf_reset_headroom(pkt);
 215         pkt->data_len = tx_pkt_seg_lengths[0];
 216         pkt->ol_flags &= RTE_MBUF_F_EXTERNAL;
 217         pkt->ol_flags |= ol_flags;
 218         pkt->vlan_tci = vlan_tci;
 219         pkt->vlan_tci_outer = vlan_tci_outer;
 220         pkt->l2_len = sizeof(struct rte_ether_hdr);
 221         pkt->l3_len = sizeof(struct rte_ipv4_hdr);
 222
 223         pkt_len = pkt->data_len;
 224         pkt_seg = pkt;
 225         for (i = 1; i < nb_segs; i++) {
 226                 pkt_seg->next = pkt_segs[i - 1];
 227                 pkt_seg = pkt_seg->next;
 228                 pkt_seg->data_len = tx_pkt_seg_lengths[i];
 229                 pkt_len += pkt_seg->data_len;
 230         }
 231         pkt_seg->next = NULL; /* Last segment of packet. */
 232         /*
 233          * Copy headers in first packet segment(s).
 234          */
 235         copy_buf_to_pkt(eth_hdr, sizeof(*eth_hdr), pkt, 0);
 236         copy_buf_to_pkt(&pkt_ip_hdr, sizeof(pkt_ip_hdr), pkt,
 237                         sizeof(struct rte_ether_hdr));
 238         if (txonly_multi_flow) {
 239                 uint8_t  ip_var = RTE_PER_LCORE(_ip_var);
 240                 struct rte_ipv4_hdr *ip_hdr;
 241                 uint32_t addr;
 242
 243                 ip_hdr = rte_pktmbuf_mtod_offset(pkt,
 244                                 struct rte_ipv4_hdr *,
 245                                 sizeof(struct rte_ether_hdr));
 246                 /*
 247                  * Generate multiple flows by varying IP src addr. This
 248                  * enables packets are well distributed by RSS in
 249                  * receiver side if any and txonly mode can be a decent
 250                  * packet generator for developer's quick performance
 251                  * regression test.
 252                  */
 253                 addr = (tx_ip_dst_addr | (ip_var++ << 8)) + rte_lcore_id();
 254                 ip_hdr->src_addr = rte_cpu_to_be_32(addr);
 255                 RTE_PER_LCORE(_ip_var) = ip_var;
 256         }
 257         copy_buf_to_pkt(&pkt_udp_hdr, sizeof(pkt_udp_hdr), pkt,
 258                         sizeof(struct rte_ether_hdr) +
 259                         sizeof(struct rte_ipv4_hdr));
 260
 261         if (unlikely(tx_pkt_split == TX_PKT_SPLIT_RND) || txonly_multi_flow)
 262                 update_pkt_header(pkt, pkt_len);
 263
 264         if (unlikely(timestamp_enable)) {
 265                 uint64_t skew = RTE_PER_LCORE(timestamp_qskew);
 266                 struct tx_timestamp timestamp_mark;
 267
 268                 if (unlikely(timestamp_init_req !=
 269                                 RTE_PER_LCORE(timestamp_idone))) {
 270                         struct rte_eth_dev_info dev_info;
 271                         unsigned int txqs_n;
 272                         uint64_t phase;
 273                         int ret;
 274
 275                         ret = eth_dev_info_get_print_err(fs->tx_port, &dev_info);
 276                         if (ret != 0) {
 277                                 TESTPMD_LOG(ERR,
 278                                         "Failed to get device info for port %d,"
 279                                         "could not finish timestamp init",
 280                                         fs->tx_port);
 281                                 return false;
 282                         }
 283                         txqs_n = dev_info.nb_tx_queues;
 284                         phase = tx_pkt_times_inter * fs->tx_queue /
 285                                          (txqs_n ? txqs_n : 1);
 286                         /*
 287                          * Initialize the scheduling time phase shift
 288                          * depending on queue index.
 289                          */
 290                         skew = timestamp_initial[fs->tx_port] +
 291                                tx_pkt_times_inter + phase;
 292                         RTE_PER_LCORE(timestamp_qskew) = skew;
 293                         RTE_PER_LCORE(timestamp_idone) = timestamp_init_req;
 294                 }
 295                 timestamp_mark.pkt_idx = rte_cpu_to_be_16(idx);
 296                 timestamp_mark.queue_idx = rte_cpu_to_be_16(fs->tx_queue);
 297                 timestamp_mark.signature = rte_cpu_to_be_32(0xBEEFC0DE);
 298                 if (unlikely(!idx)) {
 299                         skew += tx_pkt_times_inter;
 300                         pkt->ol_flags |= timestamp_mask;
 301                         *RTE_MBUF_DYNFIELD
 302                                 (pkt, timestamp_off, uint64_t *) = skew;
 303                         RTE_PER_LCORE(timestamp_qskew) = skew;
 304                         timestamp_mark.ts = rte_cpu_to_be_64(skew);
 305                 } else if (tx_pkt_times_intra) {
 306                         skew += tx_pkt_times_intra;
 307                         pkt->ol_flags |= timestamp_mask;
 308                         *RTE_MBUF_DYNFIELD
 309                                 (pkt, timestamp_off, uint64_t *) = skew;
 310                         RTE_PER_LCORE(timestamp_qskew) = skew;
 311                         timestamp_mark.ts = rte_cpu_to_be_64(skew);
 312                 } else {
 313                         timestamp_mark.ts = RTE_BE64(0);
 314                 }
 315                 copy_buf_to_pkt(&timestamp_mark, sizeof(timestamp_mark), pkt,
 316                         sizeof(struct rte_ether_hdr) +
 317                         sizeof(struct rte_ipv4_hdr) +
 318                         sizeof(pkt_udp_hdr));
 319         }
 320         /*
 321          * Complete first mbuf of packet and append it to the
 322          * burst of packets to be transmitted.
 323          */
 324         pkt->nb_segs = nb_segs;
 325         pkt->pkt_len = pkt_len;
 326
 327         return true;
 328 }
 329
 330 /*
 331  * Transmit a burst of multi-segments packets.
 332  */
 333 static void
 334 pkt_burst_transmit(struct fwd_stream *fs)
 335 {
 336         struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 337         struct rte_port *txp;
 338         struct rte_mbuf *pkt;
 339         struct rte_mempool *mbp;
 340         struct rte_ether_hdr eth_hdr;
 341         uint16_t nb_tx;
 342         uint16_t nb_pkt;
 343         uint16_t vlan_tci, vlan_tci_outer;
 344         uint32_t retry;
 345         uint64_t ol_flags = 0;
 346         uint64_t tx_offloads;
 347         uint64_t start_tsc = 0;
 348
 349         get_start_cycles(&start_tsc);
 350
 351         mbp = current_fwd_lcore()->mbp;
 352         txp = &ports[fs->tx_port];
 353         tx_offloads = txp->dev_conf.txmode.offloads;
 354         vlan_tci = txp->tx_vlan_id;
 355         vlan_tci_outer = txp->tx_vlan_id_outer;
 356         if (tx_offloads & RTE_ETH_TX_OFFLOAD_VLAN_INSERT)
 357                 ol_flags = RTE_MBUF_F_TX_VLAN;
 358         if (tx_offloads & RTE_ETH_TX_OFFLOAD_QINQ_INSERT)
 359                 ol_flags |= RTE_MBUF_F_TX_QINQ;
 360         if (tx_offloads & RTE_ETH_TX_OFFLOAD_MACSEC_INSERT)
 361                 ol_flags |= RTE_MBUF_F_TX_MACSEC;
 362
 363         /*
 364          * Initialize Ethernet header.
 365          */
 366         rte_ether_addr_copy(&peer_eth_addrs[fs->peer_addr], &eth_hdr.dst_addr);
 367         rte_ether_addr_copy(&ports[fs->tx_port].eth_addr, &eth_hdr.src_addr);
 368         eth_hdr.ether_type = rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4);
 369
 370         if (rte_mempool_get_bulk(mbp, (void **)pkts_burst,
 371                                 nb_pkt_per_burst) == 0) {
 372                 for (nb_pkt = 0; nb_pkt < nb_pkt_per_burst; nb_pkt++) {
 373                         if (unlikely(!pkt_burst_prepare(pkts_burst[nb_pkt], mbp,
 374                                                         &eth_hdr, vlan_tci,
 375                                                         vlan_tci_outer,
 376                                                         ol_flags,
 377                                                         nb_pkt, fs))) {
 378                                 rte_mempool_put_bulk(mbp,
 379                                                 (void **)&pkts_burst[nb_pkt],
 380                                                 nb_pkt_per_burst - nb_pkt);
 381                                 break;
 382                         }
 383                 }
 384         } else {
 385                 for (nb_pkt = 0; nb_pkt < nb_pkt_per_burst; nb_pkt++) {
 386                         pkt = rte_mbuf_raw_alloc(mbp);
 387                         if (pkt == NULL)
 388                                 break;
 389                         if (unlikely(!pkt_burst_prepare(pkt, mbp, &eth_hdr,
 390                                                         vlan_tci,
 391                                                         vlan_tci_outer,
 392                                                         ol_flags,
 393                                                         nb_pkt, fs))) {
 394                                 rte_pktmbuf_free(pkt);
 395                                 break;
 396                         }
 397                         pkts_burst[nb_pkt] = pkt;
 398                 }
 399         }
 400
 401         if (nb_pkt == 0)
 402                 return;
 403
 404         nb_tx = rte_eth_tx_burst(fs->tx_port, fs->tx_queue, pkts_burst, nb_pkt);
 405
 406         /*
 407          * Retry if necessary
 408          */
 409         if (unlikely(nb_tx < nb_pkt) && fs->retry_enabled) {
 410                 retry = 0;
 411                 while (nb_tx < nb_pkt && retry++ < burst_tx_retry_num) {
 412                         rte_delay_us(burst_tx_delay_time);
 413                         nb_tx += rte_eth_tx_burst(fs->tx_port, fs->tx_queue,
 414                                         &pkts_burst[nb_tx], nb_pkt - nb_tx);
 415                 }
 416         }
 417         fs->tx_packets += nb_tx;
 418
 419         if (txonly_multi_flow)
 420                 RTE_PER_LCORE(_ip_var) -= nb_pkt - nb_tx;
 421
 422         inc_tx_burst_stats(fs, nb_tx);
 423         if (unlikely(nb_tx < nb_pkt)) {
 424                 if (verbose_level > 0 && fs->fwd_dropped == 0)
 425                         printf("port %d tx_queue %d - drop "
 426                                "(nb_pkt:%u - nb_tx:%u)=%u packets\n",
 427                                fs->tx_port, fs->tx_queue,
 428                                (unsigned) nb_pkt, (unsigned) nb_tx,
 429                                (unsigned) (nb_pkt - nb_tx));
 430                 fs->fwd_dropped += (nb_pkt - nb_tx);
 431                 do {
 432                         rte_pktmbuf_free(pkts_burst[nb_tx]);
 433                 } while (++nb_tx < nb_pkt);
 434         }
 435
 436         get_end_cycles(fs, start_tsc);
 437 }
 438
 439 static int
 440 tx_only_begin(portid_t pi)
 441 {
 442         uint16_t pkt_hdr_len, pkt_data_len;
 443         int dynf;
 444
 445         pkt_hdr_len = (uint16_t)(sizeof(struct rte_ether_hdr) +
 446                                  sizeof(struct rte_ipv4_hdr) +
 447                                  sizeof(struct rte_udp_hdr));
 448         pkt_data_len = tx_pkt_length - pkt_hdr_len;
 449
 450         if ((tx_pkt_split == TX_PKT_SPLIT_RND || txonly_multi_flow) &&
 451             tx_pkt_seg_lengths[0] < pkt_hdr_len) {
 452                 TESTPMD_LOG(ERR,
 453                             "Random segment number or multiple flow is enabled, "
 454                             "but tx_pkt_seg_lengths[0] %u < %u (needed)\n",
 455                             tx_pkt_seg_lengths[0], pkt_hdr_len);
 456                 return -EINVAL;
 457         }
 458
 459         setup_pkt_udp_ip_headers(&pkt_ip_hdr, &pkt_udp_hdr, pkt_data_len);
 460
 461         timestamp_enable = false;
 462         timestamp_mask = 0;
 463         timestamp_off = -1;
 464         RTE_PER_LCORE(timestamp_qskew) = 0;
 465         dynf = rte_mbuf_dynflag_lookup
 466                                 (RTE_MBUF_DYNFLAG_TX_TIMESTAMP_NAME, NULL);
 467         if (dynf >= 0)
 468                 timestamp_mask = 1ULL << dynf;
 469         dynf = rte_mbuf_dynfield_lookup
 470                                 (RTE_MBUF_DYNFIELD_TIMESTAMP_NAME, NULL);
 471         if (dynf >= 0)
 472                 timestamp_off = dynf;
 473         timestamp_enable = tx_pkt_times_inter &&
 474                            timestamp_mask &&
 475                            timestamp_off >= 0 &&
 476                            !rte_eth_read_clock(pi, &timestamp_initial[pi]);
 477
 478         if (timestamp_enable) {
 479                 pkt_hdr_len += sizeof(struct tx_timestamp);
 480
 481                 if (tx_pkt_split == TX_PKT_SPLIT_RND) {
 482                         if (tx_pkt_seg_lengths[0] < pkt_hdr_len) {
 483                                 TESTPMD_LOG(ERR,
 484                                             "Time stamp and random segment number are enabled, "
 485                                             "but tx_pkt_seg_lengths[0] %u < %u (needed)\n",
 486                                             tx_pkt_seg_lengths[0], pkt_hdr_len);
 487                                 return -EINVAL;
 488                         }
 489                 } else {
 490                         uint16_t total = 0;
 491                         uint8_t i;
 492
 493                         for (i = 0; i < tx_pkt_nb_segs; i++) {
 494                                 total += tx_pkt_seg_lengths[i];
 495                                 if (total >= pkt_hdr_len)
 496                                         break;
 497                         }
 498
 499                         if (total < pkt_hdr_len) {
 500                                 TESTPMD_LOG(ERR,
 501                                             "Not enough Tx segment space for time stamp info, "
 502                                             "total %u < %u (needed)\n",
 503                                             total, pkt_hdr_len);
 504                                 return -EINVAL;
 505                         }
 506                 }
 507                 timestamp_init_req++;
 508         }
 509
 510         /* Make sure all settings are visible on forwarding cores.*/
 511         rte_wmb();
 512         return 0;
 513 }
 514
 515 struct fwd_engine tx_only_engine = {
 516         .fwd_mode_name  = "txonly",
 517         .port_fwd_begin = tx_only_begin,
 518         .port_fwd_end   = NULL,
 519         .packet_fwd     = pkt_burst_transmit,
 520 };