1 /* Evaluate MSG_ZEROCOPY
3 * Send traffic between two processes over one of the supported
9 * - SOCK_DGRAM with UDP_CORK
11 * - SOCK_RAW with IP_HDRINCL
17 * Start this program on two connected hosts, one in send mode and
18 * the other with option '-r' to put it in receiver mode.
20 * If zerocopy mode ('-z') is enabled, the sender will verify that
21 * the kernel queues completions on the error queue for all zerocopy
27 #include <arpa/inet.h>
31 #include <linux/errqueue.h>
32 #include <linux/if_packet.h>
33 #include <linux/ipv6.h>
34 #include <linux/socket.h>
35 #include <linux/sockios.h>
36 #include <net/ethernet.h>
38 #include <netinet/ip.h>
39 #include <netinet/ip6.h>
40 #include <netinet/tcp.h>
41 #include <netinet/udp.h>
49 #include <sys/ioctl.h>
50 #include <sys/socket.h>
53 #include <sys/types.h>
57 #ifndef SO_EE_ORIGIN_ZEROCOPY
58 #define SO_EE_ORIGIN_ZEROCOPY 5
62 #define SO_ZEROCOPY 60
65 #ifndef SO_EE_CODE_ZEROCOPY_COPIED
66 #define SO_EE_CODE_ZEROCOPY_COPIED 1
70 #define MSG_ZEROCOPY 0x4000000
74 static bool cfg_cork_mixed;
75 static int cfg_cpu = -1; /* default: pin to last cpu */
76 static int cfg_family = PF_UNSPEC;
77 static int cfg_ifindex = 1;
78 static int cfg_payload_len;
79 static int cfg_port = 8000;
81 static int cfg_runtime_ms = 4200;
82 static int cfg_verbose;
83 static int cfg_waittime_ms = 500;
84 static bool cfg_zerocopy;
86 static socklen_t cfg_alen;
87 static struct sockaddr_storage cfg_dst_addr;
88 static struct sockaddr_storage cfg_src_addr;
90 static char payload[IP_MAXPACKET];
91 static long packets, bytes, completions, expected_completions;
92 static int zerocopied = -1;
93 static uint32_t next_completion;
95 static unsigned long gettimeofday_ms(void)
99 gettimeofday(&tv, NULL);
100 return (tv.tv_sec * 1000) + (tv.tv_usec / 1000);
103 static uint16_t get_ip_csum(const uint16_t *start, int num_words)
105 unsigned long sum = 0;
108 for (i = 0; i < num_words; i++)
112 sum = (sum & 0xFFFF) + (sum >> 16);
117 static int do_setcpu(int cpu)
123 if (sched_setaffinity(0, sizeof(mask), &mask))
124 fprintf(stderr, "cpu: unable to pin, may increase variance.\n");
125 else if (cfg_verbose)
126 fprintf(stderr, "cpu: %u\n", cpu);
131 static void do_setsockopt(int fd, int level, int optname, int val)
133 if (setsockopt(fd, level, optname, &val, sizeof(val)))
134 error(1, errno, "setsockopt %d.%d: %d", level, optname, val);
137 static int do_poll(int fd, int events)
146 ret = poll(&pfd, 1, cfg_waittime_ms);
148 error(1, errno, "poll");
150 return ret && (pfd.revents & events);
153 static int do_accept(int fd)
157 fd = accept(fda, NULL, NULL);
159 error(1, errno, "accept");
161 error(1, errno, "close listen sock");
166 static bool do_sendmsg(int fd, struct msghdr *msg, bool do_zerocopy)
168 int ret, len, i, flags;
171 for (i = 0; i < msg->msg_iovlen; i++)
172 len += msg->msg_iov[i].iov_len;
174 flags = MSG_DONTWAIT;
176 flags |= MSG_ZEROCOPY;
178 ret = sendmsg(fd, msg, flags);
179 if (ret == -1 && errno == EAGAIN)
182 error(1, errno, "send");
183 if (cfg_verbose && ret != len)
184 fprintf(stderr, "send: ret=%u != %u\n", ret, len);
189 if (do_zerocopy && ret)
190 expected_completions++;
196 static void do_sendmsg_corked(int fd, struct msghdr *msg)
198 bool do_zerocopy = cfg_zerocopy;
199 int i, payload_len, extra_len;
201 /* split up the packet. for non-multiple, make first buffer longer */
202 payload_len = cfg_payload_len / cfg_cork;
203 extra_len = cfg_payload_len - (cfg_cork * payload_len);
205 do_setsockopt(fd, IPPROTO_UDP, UDP_CORK, 1);
207 for (i = 0; i < cfg_cork; i++) {
209 /* in mixed-frags mode, alternate zerocopy and copy frags
210 * start with non-zerocopy, to ensure attach later works
213 do_zerocopy = (i & 1);
215 msg->msg_iov[0].iov_len = payload_len + extra_len;
218 do_sendmsg(fd, msg, do_zerocopy);
221 do_setsockopt(fd, IPPROTO_UDP, UDP_CORK, 0);
224 static int setup_iph(struct iphdr *iph, uint16_t payload_len)
226 struct sockaddr_in *daddr = (void *) &cfg_dst_addr;
227 struct sockaddr_in *saddr = (void *) &cfg_src_addr;
229 memset(iph, 0, sizeof(*iph));
235 iph->saddr = saddr->sin_addr.s_addr;
236 iph->daddr = daddr->sin_addr.s_addr;
237 iph->protocol = IPPROTO_EGP;
238 iph->tot_len = htons(sizeof(*iph) + payload_len);
239 iph->check = get_ip_csum((void *) iph, iph->ihl << 1);
244 static int setup_ip6h(struct ipv6hdr *ip6h, uint16_t payload_len)
246 struct sockaddr_in6 *daddr = (void *) &cfg_dst_addr;
247 struct sockaddr_in6 *saddr = (void *) &cfg_src_addr;
249 memset(ip6h, 0, sizeof(*ip6h));
252 ip6h->payload_len = htons(payload_len);
253 ip6h->nexthdr = IPPROTO_EGP;
255 ip6h->saddr = saddr->sin6_addr;
256 ip6h->daddr = daddr->sin6_addr;
258 return sizeof(*ip6h);
262 static void setup_sockaddr(int domain, const char *str_addr,
263 struct sockaddr_storage *sockaddr)
265 struct sockaddr_in6 *addr6 = (void *) sockaddr;
266 struct sockaddr_in *addr4 = (void *) sockaddr;
270 memset(addr4, 0, sizeof(*addr4));
271 addr4->sin_family = AF_INET;
272 addr4->sin_port = htons(cfg_port);
274 inet_pton(AF_INET, str_addr, &(addr4->sin_addr)) != 1)
275 error(1, 0, "ipv4 parse error: %s", str_addr);
278 memset(addr6, 0, sizeof(*addr6));
279 addr6->sin6_family = AF_INET6;
280 addr6->sin6_port = htons(cfg_port);
282 inet_pton(AF_INET6, str_addr, &(addr6->sin6_addr)) != 1)
283 error(1, 0, "ipv6 parse error: %s", str_addr);
286 error(1, 0, "illegal domain");
290 static int do_setup_tx(int domain, int type, int protocol)
294 fd = socket(domain, type, protocol);
296 error(1, errno, "socket t");
298 do_setsockopt(fd, SOL_SOCKET, SO_SNDBUF, 1 << 21);
300 do_setsockopt(fd, SOL_SOCKET, SO_ZEROCOPY, 1);
302 if (domain != PF_PACKET)
303 if (connect(fd, (void *) &cfg_dst_addr, cfg_alen))
304 error(1, errno, "connect");
309 static bool do_recv_completion(int fd)
311 struct sock_extended_err *serr;
312 struct msghdr msg = {};
314 uint32_t hi, lo, range;
318 msg.msg_control = control;
319 msg.msg_controllen = sizeof(control);
321 ret = recvmsg(fd, &msg, MSG_ERRQUEUE);
322 if (ret == -1 && errno == EAGAIN)
325 error(1, errno, "recvmsg notification");
326 if (msg.msg_flags & MSG_CTRUNC)
327 error(1, errno, "recvmsg notification: truncated");
329 cm = CMSG_FIRSTHDR(&msg);
331 error(1, 0, "cmsg: no cmsg");
332 if (!((cm->cmsg_level == SOL_IP && cm->cmsg_type == IP_RECVERR) ||
333 (cm->cmsg_level == SOL_IPV6 && cm->cmsg_type == IPV6_RECVERR) ||
334 (cm->cmsg_level == SOL_PACKET && cm->cmsg_type == PACKET_TX_TIMESTAMP)))
335 error(1, 0, "serr: wrong type: %d.%d",
336 cm->cmsg_level, cm->cmsg_type);
338 serr = (void *) CMSG_DATA(cm);
339 if (serr->ee_origin != SO_EE_ORIGIN_ZEROCOPY)
340 error(1, 0, "serr: wrong origin: %u", serr->ee_origin);
341 if (serr->ee_errno != 0)
342 error(1, 0, "serr: wrong error code: %u", serr->ee_errno);
348 /* Detect notification gaps. These should not happen often, if at all.
349 * Gaps can occur due to drops, reordering and retransmissions.
351 if (lo != next_completion)
352 fprintf(stderr, "gap: %u..%u does not append to %u\n",
353 lo, hi, next_completion);
354 next_completion = hi + 1;
356 zerocopy = !(serr->ee_code & SO_EE_CODE_ZEROCOPY_COPIED);
357 if (zerocopied == -1)
358 zerocopied = zerocopy;
359 else if (zerocopied != zerocopy) {
360 fprintf(stderr, "serr: inconsistent\n");
361 zerocopied = zerocopy;
364 if (cfg_verbose >= 2)
365 fprintf(stderr, "completed: %u (h=%u l=%u)\n",
368 completions += range;
372 /* Read all outstanding messages on the errqueue */
373 static void do_recv_completions(int fd)
375 while (do_recv_completion(fd)) {}
378 /* Wait for all remaining completions on the errqueue */
379 static void do_recv_remaining_completions(int fd)
381 int64_t tstop = gettimeofday_ms() + cfg_waittime_ms;
383 while (completions < expected_completions &&
384 gettimeofday_ms() < tstop) {
385 if (do_poll(fd, POLLERR))
386 do_recv_completions(fd);
389 if (completions < expected_completions)
390 fprintf(stderr, "missing notifications: %lu < %lu\n",
391 completions, expected_completions);
394 static void do_tx(int domain, int type, int protocol)
396 struct iovec iov[3] = { {0} };
397 struct sockaddr_ll laddr;
398 struct msghdr msg = {0};
407 fd = do_setup_tx(domain, type, protocol);
409 if (domain == PF_PACKET) {
410 uint16_t proto = cfg_family == PF_INET ? ETH_P_IP : ETH_P_IPV6;
412 /* sock_raw passes ll header as data */
413 if (type == SOCK_RAW) {
414 memset(eth.h_dest, 0x06, ETH_ALEN);
415 memset(eth.h_source, 0x02, ETH_ALEN);
416 eth.h_proto = htons(proto);
417 iov[0].iov_base = ð
418 iov[0].iov_len = sizeof(eth);
422 /* both sock_raw and sock_dgram expect name */
423 memset(&laddr, 0, sizeof(laddr));
424 laddr.sll_family = AF_PACKET;
425 laddr.sll_ifindex = cfg_ifindex;
426 laddr.sll_protocol = htons(proto);
427 laddr.sll_halen = ETH_ALEN;
429 memset(laddr.sll_addr, 0x06, ETH_ALEN);
431 msg.msg_name = &laddr;
432 msg.msg_namelen = sizeof(laddr);
435 /* packet and raw sockets with hdrincl must pass network header */
436 if (domain == PF_PACKET || protocol == IPPROTO_RAW) {
437 if (cfg_family == PF_INET)
438 iov[1].iov_len = setup_iph(&nh.iph, cfg_payload_len);
440 iov[1].iov_len = setup_ip6h(&nh.ip6h, cfg_payload_len);
442 iov[1].iov_base = (void *) &nh;
446 iov[2].iov_base = payload;
447 iov[2].iov_len = cfg_payload_len;
449 msg.msg_iov = &iov[3 - msg.msg_iovlen];
451 tstop = gettimeofday_ms() + cfg_runtime_ms;
454 do_sendmsg_corked(fd, &msg);
456 do_sendmsg(fd, &msg, cfg_zerocopy);
458 while (!do_poll(fd, POLLOUT)) {
460 do_recv_completions(fd);
463 } while (gettimeofday_ms() < tstop);
466 do_recv_remaining_completions(fd);
469 error(1, errno, "close");
471 fprintf(stderr, "tx=%lu (%lu MB) txc=%lu zc=%c\n",
472 packets, bytes >> 20, completions,
473 zerocopied == 1 ? 'y' : 'n');
476 static int do_setup_rx(int domain, int type, int protocol)
480 /* If tx over PF_PACKET, rx over PF_INET(6)/SOCK_RAW,
481 * to recv the only copy of the packet, not a clone
483 if (domain == PF_PACKET)
484 error(1, 0, "Use PF_INET/SOCK_RAW to read");
486 if (type == SOCK_RAW && protocol == IPPROTO_RAW)
487 error(1, 0, "IPPROTO_RAW: not supported on Rx");
489 fd = socket(domain, type, protocol);
491 error(1, errno, "socket r");
493 do_setsockopt(fd, SOL_SOCKET, SO_RCVBUF, 1 << 21);
494 do_setsockopt(fd, SOL_SOCKET, SO_RCVLOWAT, 1 << 16);
495 do_setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, 1);
497 if (bind(fd, (void *) &cfg_dst_addr, cfg_alen))
498 error(1, errno, "bind");
500 if (type == SOCK_STREAM) {
502 error(1, errno, "listen");
509 /* Flush all outstanding bytes for the tcp receive queue */
510 static void do_flush_tcp(int fd)
514 /* MSG_TRUNC flushes up to len bytes */
515 ret = recv(fd, NULL, 1 << 21, MSG_TRUNC | MSG_DONTWAIT);
516 if (ret == -1 && errno == EAGAIN)
519 error(1, errno, "flush");
527 /* Flush all outstanding datagrams. Verify first few bytes of each. */
528 static void do_flush_datagram(int fd, int type)
533 /* MSG_TRUNC will return full datagram length */
534 ret = recv(fd, buf, sizeof(buf), MSG_DONTWAIT | MSG_TRUNC);
535 if (ret == -1 && errno == EAGAIN)
538 /* raw ipv4 return with header, raw ipv6 without */
539 if (cfg_family == PF_INET && type == SOCK_RAW) {
540 off += sizeof(struct iphdr);
541 ret -= sizeof(struct iphdr);
545 error(1, errno, "recv");
546 if (ret != cfg_payload_len)
547 error(1, 0, "recv: ret=%u != %u", ret, cfg_payload_len);
548 if (ret > sizeof(buf) - off)
549 ret = sizeof(buf) - off;
550 if (memcmp(buf + off, payload, ret))
551 error(1, 0, "recv: data mismatch");
554 bytes += cfg_payload_len;
557 static void do_rx(int domain, int type, int protocol)
562 fd = do_setup_rx(domain, type, protocol);
564 tstop = gettimeofday_ms() + cfg_runtime_ms;
566 if (type == SOCK_STREAM)
569 do_flush_datagram(fd, type);
573 } while (gettimeofday_ms() < tstop);
576 error(1, errno, "close");
578 fprintf(stderr, "rx=%lu (%lu MB)\n", packets, bytes >> 20);
581 static void do_test(int domain, int type, int protocol)
585 if (cfg_cork && (domain == PF_PACKET || type != SOCK_DGRAM))
586 error(1, 0, "can only cork udp sockets");
590 for (i = 0; i < IP_MAXPACKET; i++)
591 payload[i] = 'a' + (i % 26);
594 do_rx(domain, type, protocol);
596 do_tx(domain, type, protocol);
599 static void usage(const char *filepath)
601 error(1, 0, "Usage: %s [options] <test>", filepath);
604 static void parse_opts(int argc, char **argv)
606 const int max_payload_len = sizeof(payload) -
607 sizeof(struct ipv6hdr) -
608 sizeof(struct tcphdr) -
609 40 /* max tcp options */;
611 char *daddr = NULL, *saddr = NULL;
613 cfg_payload_len = max_payload_len;
615 while ((c = getopt(argc, argv, "46c:C:D:i:mp:rs:S:t:vz")) != -1) {
618 if (cfg_family != PF_UNSPEC)
619 error(1, 0, "Pass one of -4 or -6");
620 cfg_family = PF_INET;
621 cfg_alen = sizeof(struct sockaddr_in);
624 if (cfg_family != PF_UNSPEC)
625 error(1, 0, "Pass one of -4 or -6");
626 cfg_family = PF_INET6;
627 cfg_alen = sizeof(struct sockaddr_in6);
630 cfg_cork = strtol(optarg, NULL, 0);
633 cfg_cpu = strtol(optarg, NULL, 0);
639 cfg_ifindex = if_nametoindex(optarg);
640 if (cfg_ifindex == 0)
641 error(1, errno, "invalid iface: %s", optarg);
644 cfg_cork_mixed = true;
647 cfg_port = strtoul(optarg, NULL, 0);
653 cfg_payload_len = strtoul(optarg, NULL, 0);
659 cfg_runtime_ms = 200 + strtoul(optarg, NULL, 10) * 1000;
669 setup_sockaddr(cfg_family, daddr, &cfg_dst_addr);
670 setup_sockaddr(cfg_family, saddr, &cfg_src_addr);
672 if (cfg_payload_len > max_payload_len)
673 error(1, 0, "-s: payload exceeds max (%d)", max_payload_len);
674 if (cfg_cork_mixed && (!cfg_zerocopy || !cfg_cork))
675 error(1, 0, "-m: cork_mixed requires corking and zerocopy");
677 if (optind != argc - 1)
681 int main(int argc, char **argv)
683 const char *cfg_test;
685 parse_opts(argc, argv);
687 cfg_test = argv[argc - 1];
689 if (!strcmp(cfg_test, "packet"))
690 do_test(PF_PACKET, SOCK_RAW, 0);
691 else if (!strcmp(cfg_test, "packet_dgram"))
692 do_test(PF_PACKET, SOCK_DGRAM, 0);
693 else if (!strcmp(cfg_test, "raw"))
694 do_test(cfg_family, SOCK_RAW, IPPROTO_EGP);
695 else if (!strcmp(cfg_test, "raw_hdrincl"))
696 do_test(cfg_family, SOCK_RAW, IPPROTO_RAW);
697 else if (!strcmp(cfg_test, "tcp"))
698 do_test(cfg_family, SOCK_STREAM, 0);
699 else if (!strcmp(cfg_test, "udp"))
700 do_test(cfg_family, SOCK_DGRAM, 0);
702 error(1, 0, "unknown cfg_test %s", cfg_test);