1 /**************************************************************************/
2 /* CAN latency tester */
3 /* Copyright (C) 2010 Michal Sojka, DCE FEE CTU Prague */
5 /**************************************************************************/
16 #include <semaphore.h>
24 #include <sys/ioctl.h>
26 #include <sys/socket.h>
29 #include <sys/types.h>
33 #include <linux/can.h>
34 #include <linux/can/raw.h>
36 #include "histogram.h"
41 #define dbg(level, fmt, arg...) do {} while (0)
43 #define dbg(level, fmt, arg...) do { if (level <= DEBUG) { printf("candping: " fmt, ## arg); } } while (0)
46 #define INTERRUPTED_SYSCALL(errno) (errno == EINTR || errno == ERESTART)
48 #define MEMSET_ZERO(obj) memset(&(obj), 0, sizeof(obj))
50 /* Global variables */
51 volatile sig_atomic_t finish_flag = 0; /* Threads should terminate. */
52 sem_t finish_sem; /* Thread signals a termination */
54 /* Command line options */
67 /* Temporary variables */
73 struct options opt = {
84 struct timespec tic, tac;
86 unsigned invalid_frame;
89 int num_interfaces = 0;
90 int count = 0; /* Number of sent messages */
91 unsigned msg_in_progress = 0;
92 int completion_pipe[2];
97 struct timespec ts_sent, ts_sent_kern;
98 struct timespec ts_rx_onwire, ts_rx_onwire_kern;
99 struct timespec ts_rx_final, ts_rx_final_kern;
100 struct can_frame sent, received;
103 #define MAX_INFOS 10000
104 struct msg_info msg_infos[MAX_INFOS];
106 struct histogram histogram;
108 void sprint_canframe(char *buf , struct can_frame *cf, int sep) {
109 /* documentation see lib.h */
112 int dlc = (cf->can_dlc > 8)? 8 : cf->can_dlc;
114 if (cf->can_id & CAN_ERR_FLAG) {
115 sprintf(buf, "%08X#", cf->can_id & (CAN_ERR_MASK|CAN_ERR_FLAG));
117 } else if (cf->can_id & CAN_EFF_FLAG) {
118 sprintf(buf, "%08X#", cf->can_id & CAN_EFF_MASK);
121 sprintf(buf, "%03X#", cf->can_id & CAN_SFF_MASK);
125 if (cf->can_id & CAN_RTR_FLAG) /* there are no ERR frames with RTR */
126 sprintf(buf+offset, "R");
128 for (i = 0; i < dlc; i++) {
129 sprintf(buf+offset, "%02X", cf->data[i]);
131 if (sep && (i+1 < dlc))
132 sprintf(buf+offset++, ".");
136 static inline uint16_t frame_index(struct can_frame *frame)
139 if (frame->can_dlc >= 2) {
140 memcpy(&idx, frame->data, sizeof(idx));
141 if (idx >= MAX_INFOS)
142 error(1, 0, "%s idx too high", __FUNCTION__);
145 error(1, 0, "%s error", __FUNCTION__);
150 static inline struct msg_info *frame2info(struct can_frame *frame)
152 return &msg_infos[frame_index(frame)];
155 static inline char *tstamp_str(const void *ctx, struct timespec *tstamp)
157 return talloc_asprintf(ctx, "%ld.%06ld",
158 tstamp->tv_sec, tstamp->tv_nsec/1000);
161 void msg_info_print(FILE *f, struct msg_info *mi)
163 struct timespec diff;
164 void *local = talloc_new (NULL);
166 char sent[64], received[64];
168 sprint_canframe(sent, &mi->sent, true);
169 sprint_canframe(received, &mi->received, true);
171 #define S(ts) tstamp_str(local, &ts)
172 #define DIFF(a, b) (timespec_subtract(&diff, &b, &a), S(diff))
174 switch (num_interfaces) {
176 fprintf(f, "%ld: %s %s -> %s (%s) %s = %s (%s)\n",
177 num, S(mi->ts_sent), sent, S(mi->ts_rx_final_kern), S(mi->ts_rx_final), received,
178 DIFF(mi->ts_sent, mi->ts_rx_final_kern),
179 DIFF(mi->ts_sent, mi->ts_rx_final));
182 fprintf(f, "%ld: %s %s -> %s (%s) -> %s (%s) %s = %s (%s), %s (%s)\n",
183 num, S(mi->ts_sent), sent,
184 S(mi->ts_rx_onwire_kern), S(mi->ts_rx_onwire),
185 S(mi->ts_rx_final_kern), S(mi->ts_rx_final), received,
186 DIFF(mi->ts_sent, mi->ts_rx_onwire_kern),
187 DIFF(mi->ts_sent, mi->ts_rx_onwire),
188 DIFF(mi->ts_rx_onwire_kern, mi->ts_rx_final_kern),
189 DIFF(mi->ts_rx_onwire, mi->ts_rx_final));
198 /* Subtract the `struct timespec' values X and Y, storing the result in
199 RESULT. Return 1 if the difference is negative, otherwise 0. */
201 int timespec_subtract (struct timespec *result, struct timespec *x, struct timespec *yy)
203 struct timespec ylocal = *yy, *y = &ylocal;
204 /* Perform the carry for the later subtraction by updating Y. */
205 if (x->tv_nsec < y->tv_nsec) {
206 int nsec = (y->tv_nsec - x->tv_nsec) / 1000000000 + 1;
207 y->tv_nsec -= 1000000000 * nsec;
210 if (x->tv_nsec - y->tv_nsec > 1000000000) {
211 int nsec = (x->tv_nsec - y->tv_nsec) / 1000000000;
212 y->tv_nsec += 1000000000 * nsec;
216 /* Compute the time remaining to wait.
217 `tv_nsec' is certainly positive. */
218 result->tv_sec = x->tv_sec - y->tv_sec;
219 result->tv_nsec = x->tv_nsec - y->tv_nsec;
221 /* Return 1 if result is negative. */
222 return x->tv_sec < y->tv_sec;
225 void dbg_print_timespec(char *msg, struct timespec *tv)
228 printf("%s sec=%ld nsec=%ld\n", msg, tv->tv_sec, tv->tv_nsec);
231 static inline unsigned get_msg_latency_us(struct msg_info *mi)
233 struct timespec diff;
234 switch (num_interfaces) {
237 timespec_subtract(&diff, &mi->ts_rx_final, &mi->ts_rx_onwire);
239 timespec_subtract(&diff, &mi->ts_rx_final_kern, &mi->ts_rx_onwire_kern);
243 timespec_subtract(&diff, &mi->ts_rx_final, &mi->ts_sent);
245 timespec_subtract(&diff, &mi->ts_rx_final_kern, &mi->ts_sent);
250 return diff.tv_sec * 1000000 + diff.tv_nsec/1000;
253 void set_sched_policy_and_prio(int policy, int rtprio)
255 struct sched_param scheduling_parameters;
256 int maxprio=sched_get_priority_max(policy);
257 int minprio=sched_get_priority_min(policy);
259 if((rtprio < minprio) || (rtprio > maxprio))
260 error(1, 0, "The priority for requested policy is out of <%d, %d> range\n",
263 scheduling_parameters.sched_priority = rtprio;
265 if (0 != pthread_setschedparam(pthread_self(), policy, &scheduling_parameters))
266 error(1, errno, "pthread_setschedparam error");
269 void term_handler(int signum)
274 static inline int sock_get_if_index(int s, const char *if_name)
279 strcpy(ifr.ifr_name, if_name);
280 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
281 error(1, errno, "SIOCGIFINDEX '%s'", if_name);
282 return ifr.ifr_ifindex;
285 static inline get_tstamp(struct timespec *ts)
287 clock_gettime(CLOCK_REALTIME, ts);
301 debugfs = "/sys/kernel/debug";
303 strcpy(path, debugfs);
304 strcat(path,"/tracing/tracing_on");
305 trace_fd = open(path, O_WRONLY);
307 write(trace_fd, "1", 1);
309 strcpy(path, debugfs);
310 strcat(path,"/tracing/trace_marker");
311 marker_fd = open(path, O_WRONLY);
313 strcpy(path, debugfs);
314 strcat(path,"/tracing/set_ftrace_pid");
315 f = fopen(path, "w");
316 fprintf(f, "%d\n", getpid());
318 system("echo function_graph > /sys/kernel/debug/tracing/current_tracer");
319 system("echo can_send > /sys/kernel/debug/tracing/set_graph_function");
320 system("echo > /sys/kernel/debug/tracing/trace");
321 system("echo 1 > /sys/kernel/debug/tracing/tracing_enabled");
326 static inline void trace_on()
329 write(trace_fd, "1", 1);
332 static inline void trace_off(int ret)
334 if (marker_fd >= 0) {
336 sprintf(marker, "write returned %d\n", ret);
337 write(marker_fd, marker, strlen(marker));
340 write(trace_fd, "0", 1);
343 static inline void msg_info_free(struct msg_info *mi)
348 static inline bool msg_info_used(struct msg_info *mi)
353 int send_frame(int socket)
355 struct can_frame frame;
358 static int curr_msg = -1;
364 while (msg_info_used(&msg_infos[i]) && i != curr_msg) {
370 error(1, 0, "Msg info table is full! Probably, many packets were lost.");
374 frame.can_id = opt.id;
376 error(1, 0, "Length < 2 is not yet supported");
377 frame.can_dlc = opt.length;
379 memcpy(frame.data, &idx, sizeof(idx));
380 mi = frame2info(&frame);
382 mi->id = frame.can_id;
383 mi->length = frame.can_dlc;
384 get_tstamp(&mi->ts_sent);
388 ret = write(socket, &frame, sizeof(frame));
391 if (ret == -1 || num_interfaces == 1)
396 static inline send_and_check(int s)
400 if (ret != sizeof(struct can_frame)) {
401 /* if (ret == -1 && errno == ENOBUFS && opt.period_us == 0 && !opt.oneattime) { */
402 /* stats.enobufs++; */
403 /* /\* Ignore this error - pfifo_fast qeuue is full *\/ */
405 error(1, errno, "send_frame (line %d)", __LINE__);
412 static inline void get_next_timeout(struct timespec *timeout)
415 static struct timespec last = {-1, 0 };
417 clock_gettime(CLOCK_MONOTONIC, &now);
419 if (last.tv_sec == -1)
421 if (opt.period_us != 0) {
422 last.tv_sec += opt.period_us/1000000;
423 last.tv_nsec += (opt.period_us%1000000)*1000;
424 while (last.tv_nsec >= 1000000000) {
425 last.tv_nsec -= 1000000000;
428 if (timespec_subtract(timeout, &last, &now) /* is negative */) {
430 memset(timeout, 0, sizeof(*timeout));
432 } else if (opt.timeout_ms != 0) {
433 timeout->tv_sec = opt.timeout_ms/1000;
434 timeout->tv_nsec = (opt.timeout_ms%1000)*1000000;
436 error(1, 0, "Timeout and period cannot be both zero");
439 void receive(int s, struct can_frame *frame, struct timespec *ts_kern, struct timespec *ts_user)
441 char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) + CMSG_SPACE(sizeof(__u32))];
444 struct cmsghdr *cmsg;
445 struct sockaddr_can addr;
447 static uint64_t dropcnt = 0;
449 iov.iov_base = frame;
450 msg.msg_name = &addr;
453 msg.msg_control = &ctrlmsg;
455 /* these settings may be modified by recvmsg() */
456 iov.iov_len = sizeof(*frame);
457 msg.msg_namelen = sizeof(addr);
458 msg.msg_controllen = sizeof(ctrlmsg);
461 nbytes = recvmsg(s, &msg, 0);
463 error(1, errno, "recvmsg");
465 if (nbytes < sizeof(struct can_frame))
466 error(1, 0, "recvmsg: incomplete CAN frame\n");
469 MEMSET_ZERO(*ts_kern);
470 for (cmsg = CMSG_FIRSTHDR(&msg);
471 cmsg && (cmsg->cmsg_level == SOL_SOCKET);
472 cmsg = CMSG_NXTHDR(&msg,cmsg)) {
473 if (cmsg->cmsg_type == SO_TIMESTAMPNS)
474 *ts_kern = *(struct timespec *)CMSG_DATA(cmsg);
475 else if (cmsg->cmsg_type == SO_RXQ_OVFL)
476 dropcnt += *(__u32 *)CMSG_DATA(cmsg);
481 void process_tx(int s)
483 error(1, 0, "%s: not implemented", __FUNCTION__);
486 void process_on_wire_rx(int s)
488 struct timespec ts_kern, ts_user, ts_diff;
489 struct can_frame frame;
491 receive(s, &frame, &ts_kern, &ts_user);
492 mi = frame2info(&frame);
493 if (msg_info_used(mi)) {
494 mi->ts_rx_onwire_kern = ts_kern;
495 mi->ts_rx_onwire = ts_user;
497 stats.invalid_frame++;
501 void process_final_rx(int s)
503 struct timespec ts_kern, ts_user, ts_diff;
504 struct can_frame frame;
508 receive(s, &frame, &ts_kern, &ts_user);
509 mi = frame2info(&frame);
510 mi->ts_rx_final_kern = ts_kern;
511 mi->ts_rx_final = ts_user;
512 mi->received = frame;
514 histogram_add(&histogram, get_msg_latency_us(mi));
516 ret = write(completion_pipe[1], &mi, sizeof(mi));
518 error(1, errno, "completion_pipe write");
521 void *measure_thread(void *arg)
524 struct pollfd pfd[3];
525 struct timespec timeout;
526 struct sockaddr_can addr;
528 int consecutive_timeouts = 0;
532 for (i=0; i<num_interfaces; i++) {
533 if ((s = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0)
534 error(1, errno, "socket");
536 addr.can_family = AF_CAN;
537 addr.can_ifindex = sock_get_if_index(s, opt.interface[i]);
539 if (i == 0) { /* TX socket */
540 /* disable default receive filter on this RAW socket */
541 /* This is obsolete as we do not read from the socket at all, but for */
542 /* this reason we can remove the receive list in the Kernel to save a */
543 /* little (really a very little!) CPU usage. */
544 if (setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0) == -1)
545 error(1, errno, "SOL_CAN_RAW");
548 if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0)
549 error(1, errno, "bind");
551 const int timestamp_on = 1;
552 if (setsockopt(s, SOL_SOCKET, SO_TIMESTAMPNS,
553 ×tamp_on, sizeof(timestamp_on)) < 0)
554 error(1, errno, "setsockopt SO_TIMESTAMP");
556 const int dropmonitor_on = 1;
557 if (setsockopt(s, SOL_SOCKET, SO_RXQ_OVFL,
558 &dropmonitor_on, sizeof(dropmonitor_on)) < 0)
559 error(1, errno, "setsockopt SO_RXQ_OVFL not supported by your Linux Kernel");
563 pfd[i].events = POLLIN | POLLERR | ((opt.period_us == 0 && !opt.oneattime) ? POLLOUT : 0);
565 pfd[i].events = POLLIN;
568 set_sched_policy_and_prio(SCHED_FIFO, 40);
570 #define SEND() send_and_check(pfd[0].fd)
575 get_tstamp(&stats.tic);
577 while (!finish_flag &&
578 (opt.count == 0 || count < opt.count || msg_in_progress != 0)) {
580 get_next_timeout(&timeout);
581 //printf("ppoll"); fflush(stdout);
582 ret = ppoll(pfd, num_interfaces, &timeout, NULL);
583 //printf("=%d\n", ret);
586 if (!INTERRUPTED_SYSCALL(errno))
587 error(1, errno, "ppoll");
591 if (opt.count == 0 || count < opt.count) {
595 /* Lost message - send a new one */
597 consecutive_timeouts++;
598 if (consecutive_timeouts < 10)
600 else /* Something is really broken */
605 if (pfd[0].revents & (POLLIN|POLLERR)) {
606 process_tx(pfd[0].fd);
608 if (pfd[0].revents & POLLOUT) {
609 if (opt.count == 0 || count < opt.count)
614 if (num_interfaces == 3 && pfd[1].revents & POLLIN) {
615 process_on_wire_rx(pfd[1].fd);
618 if (num_interfaces == 3 && pfd[1].revents & ~POLLIN)
619 error(1, 0, "Unexpected pfd[1].revents: 0x%04x\n", pfd[1].revents);
621 i = (num_interfaces == 2) ? 1 : 2;
622 if (pfd[i].revents & POLLIN) {
623 consecutive_timeouts = 0;
624 process_final_rx(pfd[i].fd);
627 if ((opt.count == 0 || count < opt.count) &&
632 if (pfd[i].revents & ~POLLIN)
633 error(1, 0, "Unexpected pfd[%d].revents: 0x%04x\n", pfd[i].revents);
637 get_tstamp(&stats.tac);
639 for (i=0; i<num_interfaces; i++)
645 struct poptOption optionsTable[] = {
646 { "device", 'd', POPT_ARG_ARGV, &opt.interface, 'd', "Interface to use. Must be given two times (tx, rx) or three times (tx, rx1, rx2)", "interface" },
647 { "count", 'c', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.count, 0, "The count of messages to send, zero corresponds to infinity", "num"},
648 { "id", 'i', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.id, 0, "CAN ID of sent messages", "id"},
649 { "period", 'p', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.period_us, 0, "Period for sending messages or zero (default) to send as fast as possible", "us"},
650 { "timeout",'t', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.timeout_ms,0, "Timeout when period is zero", "ms"},
651 { "oneattime",'o', POPT_ARG_NONE, &opt.oneattime,0, "Send the next message only when the previous was finally received"},
652 { "verbose",'v', POPT_ARG_NONE, NULL, 'v', "Send the next message only when the previous was finally received"},
653 { "name", 'n', POPT_ARG_STRING, &opt.name, 0, "Prefix of the generated files"},
654 { "length", 'l', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.length, 0, "The length of generated messages", "bytes"},
655 { "userhist", 'u', POPT_ARG_NONE, &opt.userhist, 0, "Generate histogram from userspace timestamps"},
656 { "quiet", 'q', POPT_ARG_NONE, &opt.quiet, 0, "Do not print progress and statistics"},
658 { NULL, 0, 0, NULL, 0 }
661 int parse_options(int argc, const char *argv[])
664 poptContext optCon; /* context for parsing command-line options */
665 void *local = talloc_new (NULL);
667 optCon = poptGetContext(NULL, argc, argv, optionsTable, 0);
668 //poptSetOtherOptionHelp(optCon, "[OPTIONS]* <port>");
670 /* Now do options processing */
671 while ((c = poptGetNextOpt(optCon)) >= 0) {
679 error(1, 0, "%s: %s\n",
680 poptBadOption(optCon, POPT_BADOPTION_NOALIAS),
683 if (num_interfaces < 1 || num_interfaces > 3)
684 error(1, 0, "-d option must only be given one, two or three times");
686 if (opt.oneattime && opt.period_us)
687 error(1, 0, "oneattime and period cannot be specified at the same time");
690 char *f = talloc_asprintf(local, "%s-msgs.txt", opt.name);
691 opt.f_msgs = fopen(f, "w");
693 error(1, errno, "fopen: %s", f);
697 char *f = talloc_asprintf(local, "%s-hist.txt", opt.name);
698 opt.f_hist = fopen(f, "w");
700 error(1, errno, "fopen: %s", f);
704 char *f = talloc_asprintf(local, "%s-stat.txt", opt.name);
705 opt.f_stat = fopen(f, "w");
707 error(1, errno, "fopen: %s", f);
710 poptFreeContext(optCon);
715 void print_progress()
718 if (num_interfaces > 1)
719 printf("\rSent %5d, in progress %5d", count, msg_in_progress);
721 printf("\rSent %5d", count);
726 int main(int argc, const char *argv[])
732 parse_options(argc, argv);
734 mlockall(MCL_CURRENT | MCL_FUTURE);
736 signal(SIGINT, term_handler);
737 signal(SIGTERM, term_handler);
739 for (i=0; i<MAX_INFOS; i++)
740 msg_infos[i].id = -1;
742 histogram_init(&histogram, 5000000, 1);
744 ret = pipe(completion_pipe);
746 error(1, errno, "pipe");
747 ret = fcntl(completion_pipe[1], F_SETFL, O_NONBLOCK);
749 error(1, errno, "pipe fcntl");
753 pthread_create(&thread, 0, measure_thread, NULL);
755 struct timespec next, now, diff, allsent = {0,0};
756 clock_gettime(CLOCK_MONOTONIC, &next);
758 while (!finish_flag && (opt.count == 0 || completed < opt.count)) {
759 struct pollfd pfd[1];
760 pfd[0].fd = completion_pipe[0];
761 pfd[0].events = POLLIN;
762 ret = poll(pfd, 1, 100);
763 if (ret == -1 && !INTERRUPTED_SYSCALL(errno))
764 error(1, errno, "poll main");
765 if (ret > 0 && (pfd[0].revents & POLLIN)) {
768 ret = read(completion_pipe[0], &mi, sizeof(mi));
769 if (ret < sizeof(mi))
770 error(1, errno, "read completion returned %d", ret);
771 msg_info_print(opt.f_msgs, mi);
776 clock_gettime(CLOCK_MONOTONIC, &now);
777 if (timespec_subtract(&diff, &next, &now)) {
779 next.tv_nsec += 100000000;
780 while (next.tv_nsec >= 1000000000) {
781 next.tv_nsec -= 1000000000;
785 if (opt.count != 0 && count >= opt.count) {
786 if (allsent.tv_sec == 0)
788 timespec_subtract(&diff, &now, &allsent);
789 if (diff.tv_sec >= 1)
797 stats.lost = msg_in_progress;
799 pthread_join(thread, NULL);
801 close(completion_pipe[0]);
802 close(completion_pipe[1]);
804 histogram_fprint(&histogram, opt.f_hist);
809 fprintf(opt.f_stat, "cmdline='");
810 for (i=0; i<argc; i++)
811 fprintf(opt.f_stat, "%s%s", argv[i], i < argc-1 ? " " : "");
812 fprintf(opt.f_stat, "'\n");
814 timespec_subtract(&diff, &stats.tac, &stats.tic);
815 fprintf(opt.f_stat, "duration=%s # seconds\n", tstamp_str(NULL, &diff));
817 fprintf(opt.f_stat, "sent=%d\n", count);
818 fprintf(opt.f_stat, "overrun=%d\n", stats.overrun);
819 if (stats.overrun && !opt.quiet)
820 printf("overrun=%d\n", stats.overrun);
821 fprintf(opt.f_stat, "enobufs=%d\n", stats.enobufs);
822 if (stats.enobufs && !opt.quiet)
823 printf("enobufs=%d\n", stats.enobufs);
824 fprintf(opt.f_stat, "lost=%d\n", stats.lost);
825 if (stats.lost && !opt.quiet)
826 printf("lost=%d\n", stats.lost);
827 fprintf(opt.f_stat, "timeouts=%d\n", stats.timeouts);
828 if (stats.timeouts && !opt.quiet)
829 printf("timeouts=%d\n", stats.timeouts);
830 fprintf(opt.f_stat, "invalid_frame=%d\n", stats.timeouts);
831 if (stats.timeouts && !opt.quiet)
832 printf("invalid_frame=%d\n", stats.timeouts);