--- /dev/null
+/* Evaluate MSG_ZEROCOPY
+ *
+ * Send traffic between two processes over one of the supported
+ * protocols and modes:
+ *
+ * PF_INET/PF_INET6
+ * - SOCK_STREAM
+ * - SOCK_DGRAM
+ * - SOCK_DGRAM with UDP_CORK
+ * - SOCK_RAW
+ * - SOCK_RAW with IP_HDRINCL
+ *
+ * PF_PACKET
+ * - SOCK_DGRAM
+ * - SOCK_RAW
+ *
+ * Start this program on two connected hosts, one in send mode and
+ * the other with option '-r' to put it in receiver mode.
+ *
+ * If zerocopy mode ('-z') is enabled, the sender will verify that
+ * the kernel queues completions on the error queue for all zerocopy
+ * transfers.
+ */
+
+#define _GNU_SOURCE
+
+#include <arpa/inet.h>
+#include <error.h>
+#include <errno.h>
+#include <limits.h>
+#include <linux/errqueue.h>
+#include <linux/if_packet.h>
+#include <linux/ipv6.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <poll.h>
+#include <sched.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#ifndef SO_EE_ORIGIN_ZEROCOPY
+#define SO_EE_ORIGIN_ZEROCOPY SO_EE_ORIGIN_UPAGE
+#endif
+
+#ifndef SO_ZEROCOPY
+#define SO_ZEROCOPY 59
+#endif
+
+#ifndef SO_EE_CODE_ZEROCOPY_COPIED
+#define SO_EE_CODE_ZEROCOPY_COPIED 1
+#endif
+
+#ifndef MSG_ZEROCOPY
+#define MSG_ZEROCOPY 0x4000000
+#endif
+
+static int cfg_cork;
+static bool cfg_cork_mixed;
+static int cfg_cpu = -1; /* default: pin to last cpu */
+static int cfg_family = PF_UNSPEC;
+static int cfg_ifindex = 1;
+static int cfg_payload_len;
+static int cfg_port = 8000;
+static bool cfg_rx;
+static int cfg_runtime_ms = 4200;
+static int cfg_verbose;
+static int cfg_waittime_ms = 500;
+static bool cfg_zerocopy;
+
+static socklen_t cfg_alen;
+static struct sockaddr_storage cfg_dst_addr;
+static struct sockaddr_storage cfg_src_addr;
+
+static char payload[IP_MAXPACKET];
+static long packets, bytes, completions, expected_completions;
+static int zerocopied = -1;
+static uint32_t next_completion;
+
+static unsigned long gettimeofday_ms(void)
+{
+ struct timeval tv;
+
+ gettimeofday(&tv, NULL);
+ return (tv.tv_sec * 1000) + (tv.tv_usec / 1000);
+}
+
+static uint16_t get_ip_csum(const uint16_t *start, int num_words)
+{
+ unsigned long sum = 0;
+ int i;
+
+ for (i = 0; i < num_words; i++)
+ sum += start[i];
+
+ while (sum >> 16)
+ sum = (sum & 0xFFFF) + (sum >> 16);
+
+ return ~sum;
+}
+
+static int do_setcpu(int cpu)
+{
+ cpu_set_t mask;
+
+ CPU_ZERO(&mask);
+ CPU_SET(cpu, &mask);
+ if (sched_setaffinity(0, sizeof(mask), &mask))
+ error(1, 0, "setaffinity %d", cpu);
+
+ if (cfg_verbose)
+ fprintf(stderr, "cpu: %u\n", cpu);
+
+ return 0;
+}
+
+static void do_setsockopt(int fd, int level, int optname, int val)
+{
+ if (setsockopt(fd, level, optname, &val, sizeof(val)))
+ error(1, errno, "setsockopt %d.%d: %d", level, optname, val);
+}
+
+static int do_poll(int fd, int events)
+{
+ struct pollfd pfd;
+ int ret;
+
+ pfd.events = events;
+ pfd.revents = 0;
+ pfd.fd = fd;
+
+ ret = poll(&pfd, 1, cfg_waittime_ms);
+ if (ret == -1)
+ error(1, errno, "poll");
+
+ return ret && (pfd.revents & events);
+}
+
+static int do_accept(int fd)
+{
+ int fda = fd;
+
+ fd = accept(fda, NULL, NULL);
+ if (fd == -1)
+ error(1, errno, "accept");
+ if (close(fda))
+ error(1, errno, "close listen sock");
+
+ return fd;
+}
+
+static bool do_sendmsg(int fd, struct msghdr *msg, bool do_zerocopy)
+{
+ int ret, len, i, flags;
+
+ len = 0;
+ for (i = 0; i < msg->msg_iovlen; i++)
+ len += msg->msg_iov[i].iov_len;
+
+ flags = MSG_DONTWAIT;
+ if (do_zerocopy)
+ flags |= MSG_ZEROCOPY;
+
+ ret = sendmsg(fd, msg, flags);
+ if (ret == -1 && errno == EAGAIN)
+ return false;
+ if (ret == -1)
+ error(1, errno, "send");
+ if (cfg_verbose && ret != len)
+ fprintf(stderr, "send: ret=%u != %u\n", ret, len);
+
+ if (len) {
+ packets++;
+ bytes += ret;
+ if (do_zerocopy && ret)
+ expected_completions++;
+ }
+
+ return true;
+}
+
+static void do_sendmsg_corked(int fd, struct msghdr *msg)
+{
+ bool do_zerocopy = cfg_zerocopy;
+ int i, payload_len, extra_len;
+
+ /* split up the packet. for non-multiple, make first buffer longer */
+ payload_len = cfg_payload_len / cfg_cork;
+ extra_len = cfg_payload_len - (cfg_cork * payload_len);
+
+ do_setsockopt(fd, IPPROTO_UDP, UDP_CORK, 1);
+
+ for (i = 0; i < cfg_cork; i++) {
+
+ /* in mixed-frags mode, alternate zerocopy and copy frags
+ * start with non-zerocopy, to ensure attach later works
+ */
+ if (cfg_cork_mixed)
+ do_zerocopy = (i & 1);
+
+ msg->msg_iov[0].iov_len = payload_len + extra_len;
+ extra_len = 0;
+
+ do_sendmsg(fd, msg, do_zerocopy);
+ }
+
+ do_setsockopt(fd, IPPROTO_UDP, UDP_CORK, 0);
+}
+
+static int setup_iph(struct iphdr *iph, uint16_t payload_len)
+{
+ struct sockaddr_in *daddr = (void *) &cfg_dst_addr;
+ struct sockaddr_in *saddr = (void *) &cfg_src_addr;
+
+ memset(iph, 0, sizeof(*iph));
+
+ iph->version = 4;
+ iph->tos = 0;
+ iph->ihl = 5;
+ iph->ttl = 2;
+ iph->saddr = saddr->sin_addr.s_addr;
+ iph->daddr = daddr->sin_addr.s_addr;
+ iph->protocol = IPPROTO_EGP;
+ iph->tot_len = htons(sizeof(*iph) + payload_len);
+ iph->check = get_ip_csum((void *) iph, iph->ihl << 1);
+
+ return sizeof(*iph);
+}
+
+static int setup_ip6h(struct ipv6hdr *ip6h, uint16_t payload_len)
+{
+ struct sockaddr_in6 *daddr = (void *) &cfg_dst_addr;
+ struct sockaddr_in6 *saddr = (void *) &cfg_src_addr;
+
+ memset(ip6h, 0, sizeof(*ip6h));
+
+ ip6h->version = 6;
+ ip6h->payload_len = htons(payload_len);
+ ip6h->nexthdr = IPPROTO_EGP;
+ ip6h->hop_limit = 2;
+ ip6h->saddr = saddr->sin6_addr;
+ ip6h->daddr = daddr->sin6_addr;
+
+ return sizeof(*ip6h);
+}
+
+static void setup_sockaddr(int domain, const char *str_addr, void *sockaddr)
+{
+ struct sockaddr_in6 *addr6 = (void *) sockaddr;
+ struct sockaddr_in *addr4 = (void *) sockaddr;
+
+ switch (domain) {
+ case PF_INET:
+ addr4->sin_family = AF_INET;
+ addr4->sin_port = htons(cfg_port);
+ if (inet_pton(AF_INET, str_addr, &(addr4->sin_addr)) != 1)
+ error(1, 0, "ipv4 parse error: %s", str_addr);
+ break;
+ case PF_INET6:
+ addr6->sin6_family = AF_INET6;
+ addr6->sin6_port = htons(cfg_port);
+ if (inet_pton(AF_INET6, str_addr, &(addr6->sin6_addr)) != 1)
+ error(1, 0, "ipv6 parse error: %s", str_addr);
+ break;
+ default:
+ error(1, 0, "illegal domain");
+ }
+}
+
+static int do_setup_tx(int domain, int type, int protocol)
+{
+ int fd;
+
+ fd = socket(domain, type, protocol);
+ if (fd == -1)
+ error(1, errno, "socket t");
+
+ do_setsockopt(fd, SOL_SOCKET, SO_SNDBUF, 1 << 21);
+ if (cfg_zerocopy)
+ do_setsockopt(fd, SOL_SOCKET, SO_ZEROCOPY, 1);
+
+ if (domain != PF_PACKET)
+ if (connect(fd, (void *) &cfg_dst_addr, cfg_alen))
+ error(1, errno, "connect");
+
+ return fd;
+}
+
+static bool do_recv_completion(int fd)
+{
+ struct sock_extended_err *serr;
+ struct msghdr msg = {};
+ struct cmsghdr *cm;
+ uint32_t hi, lo, range;
+ int ret, zerocopy;
+ char control[100];
+
+ msg.msg_control = control;
+ msg.msg_controllen = sizeof(control);
+
+ ret = recvmsg(fd, &msg, MSG_ERRQUEUE);
+ if (ret == -1 && errno == EAGAIN)
+ return false;
+ if (ret == -1)
+ error(1, errno, "recvmsg notification");
+ if (msg.msg_flags & MSG_CTRUNC)
+ error(1, errno, "recvmsg notification: truncated");
+
+ cm = CMSG_FIRSTHDR(&msg);
+ if (!cm)
+ error(1, 0, "cmsg: no cmsg");
+ if (!((cm->cmsg_level == SOL_IP && cm->cmsg_type == IP_RECVERR) ||
+ (cm->cmsg_level == SOL_IPV6 && cm->cmsg_type == IPV6_RECVERR) ||
+ (cm->cmsg_level == SOL_PACKET && cm->cmsg_type == PACKET_TX_TIMESTAMP)))
+ error(1, 0, "serr: wrong type: %d.%d",
+ cm->cmsg_level, cm->cmsg_type);
+
+ serr = (void *) CMSG_DATA(cm);
+ if (serr->ee_origin != SO_EE_ORIGIN_ZEROCOPY)
+ error(1, 0, "serr: wrong origin: %u", serr->ee_origin);
+ if (serr->ee_errno != 0)
+ error(1, 0, "serr: wrong error code: %u", serr->ee_errno);
+
+ hi = serr->ee_data;
+ lo = serr->ee_info;
+ range = hi - lo + 1;
+
+ /* Detect notification gaps. These should not happen often, if at all.
+ * Gaps can occur due to drops, reordering and retransmissions.
+ */
+ if (lo != next_completion)
+ fprintf(stderr, "gap: %u..%u does not append to %u\n",
+ lo, hi, next_completion);
+ next_completion = hi + 1;
+
+ zerocopy = !(serr->ee_code & SO_EE_CODE_ZEROCOPY_COPIED);
+ if (zerocopied == -1)
+ zerocopied = zerocopy;
+ else if (zerocopied != zerocopy) {
+ fprintf(stderr, "serr: inconsistent\n");
+ zerocopied = zerocopy;
+ }
+
+ if (cfg_verbose >= 2)
+ fprintf(stderr, "completed: %u (h=%u l=%u)\n",
+ range, hi, lo);
+
+ completions += range;
+ return true;
+}
+
+/* Read all outstanding messages on the errqueue */
+static void do_recv_completions(int fd)
+{
+ while (do_recv_completion(fd)) {}
+}
+
+/* Wait for all remaining completions on the errqueue */
+static void do_recv_remaining_completions(int fd)
+{
+ int64_t tstop = gettimeofday_ms() + cfg_waittime_ms;
+
+ while (completions < expected_completions &&
+ gettimeofday_ms() < tstop) {
+ if (do_poll(fd, POLLERR))
+ do_recv_completions(fd);
+ }
+
+ if (completions < expected_completions)
+ error(1, 0, "missing notifications: %lu < %lu\n",
+ completions, expected_completions);
+}
+
+static void do_tx(int domain, int type, int protocol)
+{
+ struct iovec iov[3] = { {0} };
+ struct sockaddr_ll laddr;
+ struct msghdr msg = {0};
+ struct ethhdr eth;
+ union {
+ struct ipv6hdr ip6h;
+ struct iphdr iph;
+ } nh;
+ uint64_t tstop;
+ int fd;
+
+ fd = do_setup_tx(domain, type, protocol);
+
+ if (domain == PF_PACKET) {
+ uint16_t proto = cfg_family == PF_INET ? ETH_P_IP : ETH_P_IPV6;
+
+ /* sock_raw passes ll header as data */
+ if (type == SOCK_RAW) {
+ memset(eth.h_dest, 0x06, ETH_ALEN);
+ memset(eth.h_source, 0x02, ETH_ALEN);
+ eth.h_proto = htons(proto);
+ iov[0].iov_base = ð
+ iov[0].iov_len = sizeof(eth);
+ msg.msg_iovlen++;
+ }
+
+ /* both sock_raw and sock_dgram expect name */
+ memset(&laddr, 0, sizeof(laddr));
+ laddr.sll_family = AF_PACKET;
+ laddr.sll_ifindex = cfg_ifindex;
+ laddr.sll_protocol = htons(proto);
+ laddr.sll_halen = ETH_ALEN;
+
+ memset(laddr.sll_addr, 0x06, ETH_ALEN);
+
+ msg.msg_name = &laddr;
+ msg.msg_namelen = sizeof(laddr);
+ }
+
+ /* packet and raw sockets with hdrincl must pass network header */
+ if (domain == PF_PACKET || protocol == IPPROTO_RAW) {
+ if (cfg_family == PF_INET)
+ iov[1].iov_len = setup_iph(&nh.iph, cfg_payload_len);
+ else
+ iov[1].iov_len = setup_ip6h(&nh.ip6h, cfg_payload_len);
+
+ iov[1].iov_base = (void *) &nh;
+ msg.msg_iovlen++;
+ }
+
+ iov[2].iov_base = payload;
+ iov[2].iov_len = cfg_payload_len;
+ msg.msg_iovlen++;
+ msg.msg_iov = &iov[3 - msg.msg_iovlen];
+
+ tstop = gettimeofday_ms() + cfg_runtime_ms;
+ do {
+ if (cfg_cork)
+ do_sendmsg_corked(fd, &msg);
+ else
+ do_sendmsg(fd, &msg, cfg_zerocopy);
+
+ while (!do_poll(fd, POLLOUT)) {
+ if (cfg_zerocopy)
+ do_recv_completions(fd);
+ }
+
+ } while (gettimeofday_ms() < tstop);
+
+ if (cfg_zerocopy)
+ do_recv_remaining_completions(fd);
+
+ if (close(fd))
+ error(1, errno, "close");
+
+ fprintf(stderr, "tx=%lu (%lu MB) txc=%lu zc=%c\n",
+ packets, bytes >> 20, completions,
+ zerocopied == 1 ? 'y' : 'n');
+}
+
+static int do_setup_rx(int domain, int type, int protocol)
+{
+ int fd;
+
+ /* If tx over PF_PACKET, rx over PF_INET(6)/SOCK_RAW,
+ * to recv the only copy of the packet, not a clone
+ */
+ if (domain == PF_PACKET)
+ error(1, 0, "Use PF_INET/SOCK_RAW to read");
+
+ if (type == SOCK_RAW && protocol == IPPROTO_RAW)
+ error(1, 0, "IPPROTO_RAW: not supported on Rx");
+
+ fd = socket(domain, type, protocol);
+ if (fd == -1)
+ error(1, errno, "socket r");
+
+ do_setsockopt(fd, SOL_SOCKET, SO_RCVBUF, 1 << 21);
+ do_setsockopt(fd, SOL_SOCKET, SO_RCVLOWAT, 1 << 16);
+ do_setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, 1);
+
+ if (bind(fd, (void *) &cfg_dst_addr, cfg_alen))
+ error(1, errno, "bind");
+
+ if (type == SOCK_STREAM) {
+ if (listen(fd, 1))
+ error(1, errno, "listen");
+ fd = do_accept(fd);
+ }
+
+ return fd;
+}
+
+/* Flush all outstanding bytes for the tcp receive queue */
+static void do_flush_tcp(int fd)
+{
+ int ret;
+
+ /* MSG_TRUNC flushes up to len bytes */
+ ret = recv(fd, NULL, 1 << 21, MSG_TRUNC | MSG_DONTWAIT);
+ if (ret == -1 && errno == EAGAIN)
+ return;
+ if (ret == -1)
+ error(1, errno, "flush");
+ if (!ret)
+ return;
+
+ packets++;
+ bytes += ret;
+}
+
+/* Flush all outstanding datagrams. Verify first few bytes of each. */
+static void do_flush_datagram(int fd, int type)
+{
+ int ret, off = 0;
+ char buf[64];
+
+ /* MSG_TRUNC will return full datagram length */
+ ret = recv(fd, buf, sizeof(buf), MSG_DONTWAIT | MSG_TRUNC);
+ if (ret == -1 && errno == EAGAIN)
+ return;
+
+ /* raw ipv4 return with header, raw ipv6 without */
+ if (cfg_family == PF_INET && type == SOCK_RAW) {
+ off += sizeof(struct iphdr);
+ ret -= sizeof(struct iphdr);
+ }
+
+ if (ret == -1)
+ error(1, errno, "recv");
+ if (ret != cfg_payload_len)
+ error(1, 0, "recv: ret=%u != %u", ret, cfg_payload_len);
+ if (ret > sizeof(buf) - off)
+ ret = sizeof(buf) - off;
+ if (memcmp(buf + off, payload, ret))
+ error(1, 0, "recv: data mismatch");
+
+ packets++;
+ bytes += cfg_payload_len;
+}
+
+static void do_rx(int domain, int type, int protocol)
+{
+ uint64_t tstop;
+ int fd;
+
+ fd = do_setup_rx(domain, type, protocol);
+
+ tstop = gettimeofday_ms() + cfg_runtime_ms;
+ do {
+ if (type == SOCK_STREAM)
+ do_flush_tcp(fd);
+ else
+ do_flush_datagram(fd, type);
+
+ do_poll(fd, POLLIN);
+
+ } while (gettimeofday_ms() < tstop);
+
+ if (close(fd))
+ error(1, errno, "close");
+
+ fprintf(stderr, "rx=%lu (%lu MB)\n", packets, bytes >> 20);
+}
+
+static void do_test(int domain, int type, int protocol)
+{
+ int i;
+
+ if (cfg_cork && (domain == PF_PACKET || type != SOCK_DGRAM))
+ error(1, 0, "can only cork udp sockets");
+
+ do_setcpu(cfg_cpu);
+
+ for (i = 0; i < IP_MAXPACKET; i++)
+ payload[i] = 'a' + (i % 26);
+
+ if (cfg_rx)
+ do_rx(domain, type, protocol);
+ else
+ do_tx(domain, type, protocol);
+}
+
+static void usage(const char *filepath)
+{
+ error(1, 0, "Usage: %s [options] <test>", filepath);
+}
+
+static void parse_opts(int argc, char **argv)
+{
+ const int max_payload_len = sizeof(payload) -
+ sizeof(struct ipv6hdr) -
+ sizeof(struct tcphdr) -
+ 40 /* max tcp options */;
+ int c;
+
+ cfg_payload_len = max_payload_len;
+
+ while ((c = getopt(argc, argv, "46c:C:D:i:mp:rs:S:t:vz")) != -1) {
+ switch (c) {
+ case '4':
+ if (cfg_family != PF_UNSPEC)
+ error(1, 0, "Pass one of -4 or -6");
+ cfg_family = PF_INET;
+ cfg_alen = sizeof(struct sockaddr_in);
+ break;
+ case '6':
+ if (cfg_family != PF_UNSPEC)
+ error(1, 0, "Pass one of -4 or -6");
+ cfg_family = PF_INET6;
+ cfg_alen = sizeof(struct sockaddr_in6);
+ break;
+ case 'c':
+ cfg_cork = strtol(optarg, NULL, 0);
+ break;
+ case 'C':
+ cfg_cpu = strtol(optarg, NULL, 0);
+ break;
+ case 'D':
+ setup_sockaddr(cfg_family, optarg, &cfg_dst_addr);
+ break;
+ case 'i':
+ cfg_ifindex = if_nametoindex(optarg);
+ if (cfg_ifindex == 0)
+ error(1, errno, "invalid iface: %s", optarg);
+ break;
+ case 'm':
+ cfg_cork_mixed = true;
+ break;
+ case 'p':
+ cfg_port = htons(strtoul(optarg, NULL, 0));
+ break;
+ case 'r':
+ cfg_rx = true;
+ break;
+ case 's':
+ cfg_payload_len = strtoul(optarg, NULL, 0);
+ break;
+ case 'S':
+ setup_sockaddr(cfg_family, optarg, &cfg_src_addr);
+ break;
+ case 't':
+ cfg_runtime_ms = 200 + strtoul(optarg, NULL, 10) * 1000;
+ break;
+ case 'v':
+ cfg_verbose++;
+ break;
+ case 'z':
+ cfg_zerocopy = true;
+ break;
+ }
+ }
+
+ if (cfg_payload_len > max_payload_len)
+ error(1, 0, "-s: payload exceeds max (%d)", max_payload_len);
+ if (cfg_cork_mixed && (!cfg_zerocopy || !cfg_cork))
+ error(1, 0, "-m: cork_mixed requires corking and zerocopy");
+
+ if (optind != argc - 1)
+ usage(argv[0]);
+}
+
+int main(int argc, char **argv)
+{
+ const char *cfg_test;
+
+ parse_opts(argc, argv);
+
+ cfg_test = argv[argc - 1];
+
+ if (!strcmp(cfg_test, "packet"))
+ do_test(PF_PACKET, SOCK_RAW, 0);
+ else if (!strcmp(cfg_test, "packet_dgram"))
+ do_test(PF_PACKET, SOCK_DGRAM, 0);
+ else if (!strcmp(cfg_test, "raw"))
+ do_test(cfg_family, SOCK_RAW, IPPROTO_EGP);
+ else if (!strcmp(cfg_test, "raw_hdrincl"))
+ do_test(cfg_family, SOCK_RAW, IPPROTO_RAW);
+ else if (!strcmp(cfg_test, "tcp"))
+ do_test(cfg_family, SOCK_STREAM, 0);
+ else if (!strcmp(cfg_test, "udp"))
+ do_test(cfg_family, SOCK_DGRAM, 0);
+ else
+ error(1, 0, "unknown cfg_test %s", cfg_test);
+
+ return 0;
+}