+/**************************************************************************/
+/* CAN latency tester */
+/* Copyright (C) 2010 Michal Sojka, DCE FEE CTU Prague */
+/* License: GPLv2 */
+/**************************************************************************/
+
+#include <ctype.h>
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <math.h>
+#include <net/if.h>
+#include <pthread.h>
+#include <semaphore.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <ul_list.h>
+#include <unistd.h>
+#include <sched.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <linux/can.h>
+#include <linux/can/raw.h>
+#include <poll.h>
+
+#include "histogram.h"
+
+#ifndef DEBUG
+#define dbg(level, fmt, arg...) do {} while (0)
+#else
+#define dbg(level, fmt, arg...) do { if (level <= DEBUG) { printf("candping: " fmt, ## arg); } } while (0)
+#endif
+
+#define INTERRUPTED_SYSCALL(errno) (errno == EINTR || errno == ERESTART)
+
+#define MEMSET_ZERO(obj) memset(&(obj), 0, sizeof(obj))
+
+/* Global variables */
+volatile sig_atomic_t finish_flag = 0; /* Threads should terminate. */
+sem_t finish_sem; /* Thread signals a termination */
+
+#define MAX_INTERFACES 4
+
+/* Command line options */
+char *option_interface[MAX_INTERFACES];
+int num_interfaces = 0;
+canid_t option_id;
+unsigned option_period_us = 100000;
+
+struct msg_info {
+ canid_t id;
+ uint8_t length;
+ struct timespec ts_sent, ts_sent_kern;
+ struct timespec ts_rx_onwire, ts_rx_onwire_kern;
+ struct timespec ts_rx_final, ts_rx_final_kern;
+};
+
+#define MAX_INFOS 10000
+struct msg_info msg_infos[MAX_INFOS];
+uint16_t curr_msg = 0;
+
+static inline struct msg_info *frame2info(struct can_frame *frame)
+{
+ uint16_t idx;
+ if (frame->can_dlc == 2) {
+ memcpy(&idx, frame->data, sizeof(idx));
+ if (idx >= MAX_INFOS)
+ error(1, 0, "%s idx too high", __FUNCTION__);
+ } else
+ error(1, 0, "%s error", __FUNCTION__);
+ return &msg_infos[idx];
+}
+
+static inline char *tstamp_str(char *buf, struct timespec *tstamp)
+{
+ sprintf(buf, "%ld.%06ld", tstamp->tv_sec, tstamp->tv_nsec/1000);
+}
+
+void print_msg_info(struct msg_info *mi)
+{
+ struct timespec ts_diff1, ts_diff2;
+ char str_sent[32], str_kern[32], str_user[32], str_diff1[32], str_diff2[32];
+ timespec_subtract(&ts_diff1, &mi->ts_rx_final_kern, &mi->ts_sent);
+ timespec_subtract(&ts_diff2, &mi->ts_rx_final, &mi->ts_sent);
+ tstamp_str(str_sent, &mi->ts_sent);
+ tstamp_str(str_kern, &mi->ts_rx_final_kern);
+ tstamp_str(str_user, &mi->ts_rx_final);
+ tstamp_str(str_diff1, &ts_diff1);
+ tstamp_str(str_diff2, &ts_diff2);
+ printf("%s -> %s (%s) = %s (%s)\n", str_sent, str_user, str_kern, str_diff1, str_diff2);
+}
+
+
+/* Subtract the `struct timespec' values X and Y, storing the result in
+ RESULT. Return 1 if the difference is negative, otherwise 0. */
+
+int timespec_subtract (struct timespec *result, struct timespec *x, struct timespec *yy)
+{
+ struct timespec ylocal = *yy, *y = &ylocal;
+ /* Perform the carry for the later subtraction by updating Y. */
+ if (x->tv_nsec < y->tv_nsec) {
+ int nsec = (y->tv_nsec - x->tv_nsec) / 1000000000 + 1;
+ y->tv_nsec -= 1000000000 * nsec;
+ y->tv_sec += nsec;
+ }
+ if (x->tv_nsec - y->tv_nsec > 1000000000) {
+ int nsec = (x->tv_nsec - y->tv_nsec) / 1000000000;
+ y->tv_nsec += 1000000000 * nsec;
+ y->tv_sec -= nsec;
+ }
+
+ /* Compute the time remaining to wait.
+ `tv_nsec' is certainly positive. */
+ result->tv_sec = x->tv_sec - y->tv_sec;
+ result->tv_nsec = x->tv_nsec - y->tv_nsec;
+
+ /* Return 1 if result is negative. */
+ return x->tv_sec < y->tv_sec;
+}
+
+void dbg_print_timespec(char *msg, struct timespec *tv)
+{
+
+ printf("%s sec=%ld nsec=%ld\n", msg, tv->tv_sec, tv->tv_nsec);
+}
+
+void set_sched_policy_and_prio(int policy, int rtprio)
+{
+ struct sched_param scheduling_parameters;
+ int maxprio=sched_get_priority_max(policy);
+ int minprio=sched_get_priority_min(policy);
+
+ if((rtprio < minprio) || (rtprio > maxprio))
+ error(1, 0, "The priority for requested policy is out of <%d, %d> range\n",
+ minprio, maxprio);
+
+ scheduling_parameters.sched_priority = rtprio;
+
+ if (0 != pthread_setschedparam(pthread_self(), policy, &scheduling_parameters))
+ error(1, errno, "pthread_setschedparam error");
+}
+
+void term_handler(int signum)
+{
+ finish_flag = 1;
+}
+
+static inline int sock_get_if_index(int s, const char *if_name)
+{
+ struct ifreq ifr;
+ MEMSET_ZERO(ifr);
+
+ strcpy(ifr.ifr_name, if_name);
+ if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
+ error(1, errno, "SIOCGIFINDEX");
+ return ifr.ifr_ifindex;
+}
+
+static inline get_tstamp(struct timespec *ts)
+{
+ clock_gettime(CLOCK_REALTIME, ts);
+}
+
+int send_frame(int socket)
+{
+ struct can_frame frame;
+ struct msg_info *mi;
+ int ret;
+
+ frame.can_id = option_id;
+ frame.can_dlc = 2;
+ memcpy(frame.data, &curr_msg, sizeof(curr_msg));
+ mi = frame2info(&frame);
+
+ get_tstamp(&mi->ts_sent);
+ ret = write(socket, &frame, sizeof(frame));
+ return ret;
+}
+
+static inline void get_next_timeout(struct timespec *timeout)
+{
+ struct timespec now;
+ static struct timespec last = {-1, 0 };
+
+ clock_gettime(CLOCK_MONOTONIC, &now);
+
+ if (last.tv_sec == -1)
+ last = now;
+ last.tv_sec += option_period_us/1000000;
+ last.tv_nsec += (option_period_us%1000000)*1000;
+ while (last.tv_nsec >= 1000000000) {
+ last.tv_nsec -= 1000000000;
+ last.tv_sec++;
+ }
+ timespec_subtract(timeout, &last, &now);
+}
+
+void receive(int s, struct can_frame *frame, struct timespec *ts_kern, struct timespec *ts_user)
+{
+ char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) + CMSG_SPACE(sizeof(__u32))];
+ struct iovec iov;
+ struct msghdr msg;
+ struct cmsghdr *cmsg;
+ struct sockaddr_can addr;
+ int nbytes;
+ static uint64_t dropcnt = 0;
+
+ iov.iov_base = frame;
+ msg.msg_name = &addr;
+ msg.msg_iov = &iov;
+ msg.msg_iovlen = 1;
+ msg.msg_control = &ctrlmsg;
+
+ /* these settings may be modified by recvmsg() */
+ iov.iov_len = sizeof(*frame);
+ msg.msg_namelen = sizeof(addr);
+ msg.msg_controllen = sizeof(ctrlmsg);
+ msg.msg_flags = 0;
+
+ nbytes = recvmsg(s, &msg, 0);
+ if (nbytes < 0)
+ error(1, errno, "recvmsg");
+
+ if (nbytes < sizeof(struct can_frame))
+ error(1, 0, "recvmsg: incomplete CAN frame\n");
+
+ get_tstamp(ts_user);
+ MEMSET_ZERO(*ts_kern);
+ for (cmsg = CMSG_FIRSTHDR(&msg);
+ cmsg && (cmsg->cmsg_level == SOL_SOCKET);
+ cmsg = CMSG_NXTHDR(&msg,cmsg)) {
+ if (cmsg->cmsg_type == SO_TIMESTAMPNS)
+ *ts_kern = *(struct timespec *)CMSG_DATA(cmsg);
+ else if (cmsg->cmsg_type == SO_RXQ_OVFL)
+ dropcnt += *(__u32 *)CMSG_DATA(cmsg);
+ }
+
+}
+
+void process_tx(int s)
+{
+ error(1, 0, "%s: not implemented", __FUNCTION__);
+}
+
+void process_on_wire_rx(int s)
+{
+ error(1, 0, "%s: not implemented", __FUNCTION__);
+}
+
+
+void process_final_rx(int s)
+{
+ struct timespec ts_kern, ts_user, ts_diff;
+ struct can_frame frame;
+ struct msg_info *mi;
+ receive(s, &frame, &ts_kern, &ts_user);
+ mi = frame2info(&frame);
+ mi->ts_rx_final_kern = ts_kern;
+ mi->ts_rx_final = ts_user;
+
+ print_msg_info(mi);
+}
+
+void *measure_thread(void *arg)
+{
+ int s, i, ret;
+ struct pollfd pfd[MAX_INTERFACES];
+ struct timespec timeout;
+ struct sockaddr_can addr;
+ sigset_t set;
+
+ MEMSET_ZERO(pfd);
+
+ for (i=0; i<num_interfaces; i++) {
+ if ((s = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0)
+ error(1, errno, "socket");
+
+ addr.can_family = AF_CAN;
+ addr.can_ifindex = sock_get_if_index(s, option_interface[i]);
+
+ if (i == 0) { /* TX socket */
+ /* disable default receive filter on this RAW socket */
+ /* This is obsolete as we do not read from the socket at all, but for */
+ /* this reason we can remove the receive list in the Kernel to save a */
+ /* little (really a very little!) CPU usage. */
+ if (setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0) == -1)
+ error(1, errno, "SOL_CAN_RAW");
+ }
+
+ if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0)
+ error(1, errno, "bind");
+
+ const int timestamp_on = 1;
+ if (setsockopt(s, SOL_SOCKET, SO_TIMESTAMPNS,
+ ×tamp_on, sizeof(timestamp_on)) < 0)
+ error(1, errno, "setsockopt SO_TIMESTAMP");
+
+ const int dropmonitor_on = 1;
+ if (setsockopt(s, SOL_SOCKET, SO_RXQ_OVFL,
+ &dropmonitor_on, sizeof(dropmonitor_on)) < 0)
+ error(1, errno, "setsockopt SO_RXQ_OVFL not supported by your Linux Kernel");
+
+ pfd[i].fd = s;
+ pfd[i].events = (i == 0) ? POLLERR : POLLIN;
+ }
+
+ set_sched_policy_and_prio(SCHED_FIFO, 99);
+
+ while (!finish_flag) {
+ get_next_timeout(&timeout);
+ ret = ppoll(pfd, num_interfaces, &timeout, NULL);
+ switch (ret) {
+ case -1:
+ if (!INTERRUPTED_SYSCALL(errno))
+ error(1, errno, "ppoll");
+ break;
+ case 0:
+ ret = send_frame(pfd[0].fd);
+ if (ret != sizeof(struct can_frame))
+ error(1, errno, "send_frame");
+ break;
+ default:
+ if (pfd[0].revents != 0) {
+ process_tx(pfd[0].fd);
+ }
+ if (pfd[1].revents != 0) {
+ switch (num_interfaces) {
+ case 2: process_final_rx(pfd[1].fd); break;
+ case 3: process_on_wire_rx(pfd[1].fd); break;
+ }
+ }
+ if (pfd[2].revents != 0) {
+ process_final_rx(pfd[2].fd);
+ }
+ }
+ }
+
+ for (i=0; i<num_interfaces; i++)
+ close(pfd[i].fd);
+
+ return NULL;
+}
+
+void print_help(void)
+{
+ printf("Usage: latester -d <interface> -d <interface> ... [other options]\n"
+ "Other options:\n"
+ " -d <interface> Interface to use. Must be given two times (tx, rx) or three times (tx, rx1, rx2).\n"
+ );
+}
+
+int parse_options(int argc, char *argv[])
+{
+ int c;
+
+ opterr = 0;
+ while ((c = getopt (argc, argv, "d:h")) != -1)
+ switch (c)
+ {
+ case 'd':
+ if (num_interfaces < MAX_INTERFACES) {
+ option_interface[num_interfaces] = optarg;
+ num_interfaces++;
+ } else
+ error(1, 0, "error: Too many -d options");
+ break;
+ case 'h':
+ print_help();
+ exit(0);
+ break;
+ case '?':
+ if (isprint (optopt))
+ error (1, 0, "Unknown option `-%c'.\n", optopt);
+ else
+ error (1, 0, "Unknown option character `\\x%x'.\n", optopt);
+ default:
+ error(1, 0, "Unhandled parameter");
+ }
+ if (num_interfaces < 2 || num_interfaces > 3)
+ error(1, 0, "-d option must be given exactly 2 or 3 times");
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ pthread_t thread;
+ sigset_t set;
+ int ret;
+
+ parse_options(argc, argv);
+
+ mlockall(MCL_CURRENT | MCL_FUTURE);
+
+ signal(SIGINT, term_handler);
+ signal(SIGTERM, term_handler);
+
+
+ pthread_create(&thread, 0, measure_thread, NULL);
+
+ while (!finish_flag) {
+ sleep(1);
+ }
+
+ pthread_join(thread, NULL);
+
+ return 0;
+}
projects / can-benchmark.git / commitdiff