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"
39 #define dbg(level, fmt, arg...) do {} while (0)
41 #define dbg(level, fmt, arg...) do { if (level <= DEBUG) { printf("candping: " fmt, ## arg); } } while (0)
44 #define INTERRUPTED_SYSCALL(errno) (errno == EINTR || errno == ERESTART)
46 #define MEMSET_ZERO(obj) memset(&(obj), 0, sizeof(obj))
48 /* Global variables */
49 volatile sig_atomic_t finish_flag = 0; /* Threads should terminate. */
50 sem_t finish_sem; /* Thread signals a termination */
52 /* Command line options */
65 struct options opt = {
72 int num_interfaces = 0;
73 int count = 0; /* Number of sent messages */
74 int completion_pipe[2];
79 struct timespec ts_sent, ts_sent_kern;
80 struct timespec ts_rx_onwire, ts_rx_onwire_kern;
81 struct timespec ts_rx_final, ts_rx_final_kern;
82 struct can_frame sent, received;
85 #define MAX_INFOS 10000
86 struct msg_info msg_infos[MAX_INFOS];
88 struct histogram histogram;
90 void sprint_canframe(char *buf , struct can_frame *cf, int sep) {
91 /* documentation see lib.h */
94 int dlc = (cf->can_dlc > 8)? 8 : cf->can_dlc;
96 if (cf->can_id & CAN_ERR_FLAG) {
97 sprintf(buf, "%08X#", cf->can_id & (CAN_ERR_MASK|CAN_ERR_FLAG));
99 } else if (cf->can_id & CAN_EFF_FLAG) {
100 sprintf(buf, "%08X#", cf->can_id & CAN_EFF_MASK);
103 sprintf(buf, "%03X#", cf->can_id & CAN_SFF_MASK);
107 if (cf->can_id & CAN_RTR_FLAG) /* there are no ERR frames with RTR */
108 sprintf(buf+offset, "R");
110 for (i = 0; i < dlc; i++) {
111 sprintf(buf+offset, "%02X", cf->data[i]);
113 if (sep && (i+1 < dlc))
114 sprintf(buf+offset++, ".");
118 static inline struct msg_info *frame2info(struct can_frame *frame)
121 if (frame->can_dlc >= 2) {
122 memcpy(&idx, frame->data, sizeof(idx));
123 if (idx >= MAX_INFOS)
124 error(1, 0, "%s idx too high", __FUNCTION__);
127 error(1, 0, "%s error", __FUNCTION__);
129 return &msg_infos[idx];
132 static inline char *tstamp_str(const void *ctx, struct timespec *tstamp)
134 return talloc_asprintf(ctx, "%ld.%06ld",
135 tstamp->tv_sec, tstamp->tv_nsec/1000);
138 void msg_info_print(FILE *f, struct msg_info *mi)
140 struct timespec diff;
141 void *local = talloc_new (NULL);
143 char sent[64], received[64];
145 sprint_canframe(sent, &mi->sent, true);
146 sprint_canframe(received, &mi->received, true);
148 #define S(ts) tstamp_str(local, &ts)
149 #define DIFF(a, b) (timespec_subtract(&diff, &b, &a), S(diff))
151 if (num_interfaces == 2)
152 fprintf(f, "%ld: %s %s -> %s (%s) %s = %s (%s)\n",
153 num, S(mi->ts_sent), sent, S(mi->ts_rx_final_kern), S(mi->ts_rx_final), received,
154 DIFF(mi->ts_sent, mi->ts_rx_final_kern),
155 DIFF(mi->ts_sent, mi->ts_rx_final));
157 fprintf(f, "%ld: %s %s -> %s (%s) -> %s (%s) %s = %s (%s), %s (%s)\n",
158 num, S(mi->ts_sent), sent,
159 S(mi->ts_rx_onwire_kern), S(mi->ts_rx_onwire),
160 S(mi->ts_rx_final_kern), S(mi->ts_rx_final), received,
161 DIFF(mi->ts_sent, mi->ts_rx_onwire_kern),
162 DIFF(mi->ts_sent, mi->ts_rx_onwire),
163 DIFF(mi->ts_rx_onwire_kern, mi->ts_rx_final_kern),
164 DIFF(mi->ts_rx_onwire, mi->ts_rx_final));
171 int msg_info_store(FILE *f, struct msg_info *mi)
173 struct timespec diff;
174 void *local = talloc_new (NULL);
177 #define S(ts) tstamp_str(local, &ts)
178 #define DIFF(a, b) (timespec_subtract(&diff, &b, &a), S(diff))
180 if (num_interfaces == 2)
181 fprintf(f, "%ld %d %d %s\n",
182 num, mi->id, mi->length,
183 DIFF(mi->ts_sent, mi->ts_rx_final_kern));
185 fprintf(f, "%ld %d %d %s\n",
186 num, mi->id, mi->length,
187 DIFF(mi->ts_rx_onwire_kern, mi->ts_rx_final_kern));
194 /* Subtract the `struct timespec' values X and Y, storing the result in
195 RESULT. Return 1 if the difference is negative, otherwise 0. */
197 int timespec_subtract (struct timespec *result, struct timespec *x, struct timespec *yy)
199 struct timespec ylocal = *yy, *y = &ylocal;
200 /* Perform the carry for the later subtraction by updating Y. */
201 if (x->tv_nsec < y->tv_nsec) {
202 int nsec = (y->tv_nsec - x->tv_nsec) / 1000000000 + 1;
203 y->tv_nsec -= 1000000000 * nsec;
206 if (x->tv_nsec - y->tv_nsec > 1000000000) {
207 int nsec = (x->tv_nsec - y->tv_nsec) / 1000000000;
208 y->tv_nsec += 1000000000 * nsec;
212 /* Compute the time remaining to wait.
213 `tv_nsec' is certainly positive. */
214 result->tv_sec = x->tv_sec - y->tv_sec;
215 result->tv_nsec = x->tv_nsec - y->tv_nsec;
217 /* Return 1 if result is negative. */
218 return x->tv_sec < y->tv_sec;
221 void dbg_print_timespec(char *msg, struct timespec *tv)
224 printf("%s sec=%ld nsec=%ld\n", msg, tv->tv_sec, tv->tv_nsec);
227 static inline unsigned get_msg_latency_us(struct msg_info *mi)
229 struct timespec diff;
230 if (num_interfaces == 3)
231 timespec_subtract(&diff, &mi->ts_rx_final_kern, &mi->ts_rx_onwire_kern);
233 timespec_subtract(&diff, &mi->ts_rx_final_kern, &mi->ts_sent);
234 return diff.tv_sec * 1000000 + diff.tv_nsec/1000;
237 void set_sched_policy_and_prio(int policy, int rtprio)
239 struct sched_param scheduling_parameters;
240 int maxprio=sched_get_priority_max(policy);
241 int minprio=sched_get_priority_min(policy);
243 if((rtprio < minprio) || (rtprio > maxprio))
244 error(1, 0, "The priority for requested policy is out of <%d, %d> range\n",
247 scheduling_parameters.sched_priority = rtprio;
249 if (0 != pthread_setschedparam(pthread_self(), policy, &scheduling_parameters))
250 error(1, errno, "pthread_setschedparam error");
253 void term_handler(int signum)
258 static inline int sock_get_if_index(int s, const char *if_name)
263 strcpy(ifr.ifr_name, if_name);
264 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
265 error(1, errno, "SIOCGIFINDEX '%s'", if_name);
266 return ifr.ifr_ifindex;
269 static inline get_tstamp(struct timespec *ts)
271 clock_gettime(CLOCK_MONOTONIC, ts);
274 int send_frame(int socket)
276 struct can_frame frame;
279 static int curr_msg = -1;
285 while (msg_infos[i].id != -1 && i != curr_msg) {
291 error(1, 0, "Msg info table is full! Probably, many packets were lost.");
295 frame.can_id = opt.id;
297 error(1, 0, "Length < 2 is not yet supported");
298 frame.can_dlc = opt.length;
300 memcpy(frame.data, &idx, sizeof(idx));
301 mi = frame2info(&frame);
303 mi->id = frame.can_id;
304 mi->length = frame.can_dlc;
305 get_tstamp(&mi->ts_sent);
307 ret = write(socket, &frame, sizeof(frame));
311 void msg_info_free(struct msg_info *mi)
316 static inline void get_next_timeout(struct timespec *timeout)
319 static struct timespec last = {-1, 0 };
321 clock_gettime(CLOCK_MONOTONIC, &now);
323 if (last.tv_sec == -1)
325 if (opt.period_us != 0) {
326 last.tv_sec += opt.period_us/1000000;
327 last.tv_nsec += (opt.period_us%1000000)*1000;
328 while (last.tv_nsec >= 1000000000) {
329 last.tv_nsec -= 1000000000;
332 timespec_subtract(timeout, &last, &now);
333 } else if (opt.timeout_ms != 0) {
334 timeout->tv_sec = opt.timeout_ms/1000;
335 timeout->tv_nsec = (opt.timeout_ms%1000)*1000000;
337 error(1, 0, "Timeout and period cannot be both zero");
340 void receive(int s, struct can_frame *frame, struct timespec *ts_kern, struct timespec *ts_user)
342 char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) + CMSG_SPACE(sizeof(__u32))];
345 struct cmsghdr *cmsg;
346 struct sockaddr_can addr;
348 static uint64_t dropcnt = 0;
350 iov.iov_base = frame;
351 msg.msg_name = &addr;
354 msg.msg_control = &ctrlmsg;
356 /* these settings may be modified by recvmsg() */
357 iov.iov_len = sizeof(*frame);
358 msg.msg_namelen = sizeof(addr);
359 msg.msg_controllen = sizeof(ctrlmsg);
362 nbytes = recvmsg(s, &msg, 0);
364 error(1, errno, "recvmsg");
366 if (nbytes < sizeof(struct can_frame))
367 error(1, 0, "recvmsg: incomplete CAN frame\n");
370 MEMSET_ZERO(*ts_kern);
371 for (cmsg = CMSG_FIRSTHDR(&msg);
372 cmsg && (cmsg->cmsg_level == SOL_SOCKET);
373 cmsg = CMSG_NXTHDR(&msg,cmsg)) {
374 if (cmsg->cmsg_type == SO_TIMESTAMPNS)
375 *ts_kern = *(struct timespec *)CMSG_DATA(cmsg);
376 else if (cmsg->cmsg_type == SO_RXQ_OVFL)
377 dropcnt += *(__u32 *)CMSG_DATA(cmsg);
382 void process_tx(int s)
384 error(1, 0, "%s: not implemented", __FUNCTION__);
387 void process_on_wire_rx(int s)
389 struct timespec ts_kern, ts_user, ts_diff;
390 struct can_frame frame;
392 receive(s, &frame, &ts_kern, &ts_user);
393 mi = frame2info(&frame);
394 mi->ts_rx_onwire_kern = ts_kern;
395 mi->ts_rx_onwire = ts_user;
399 void process_final_rx(int s)
401 struct timespec ts_kern, ts_user, ts_diff;
402 struct can_frame frame;
406 receive(s, &frame, &ts_kern, &ts_user);
407 mi = frame2info(&frame);
408 mi->ts_rx_final_kern = ts_kern;
409 mi->ts_rx_final = ts_user;
410 mi->received = frame;
413 histogram_add(&histogram, get_msg_latency_us(mi));
415 ret = write(completion_pipe[1], &mi, sizeof(mi));
417 error(1, errno, "completion_pipe write");
420 void *measure_thread(void *arg)
423 struct pollfd pfd[3];
424 struct timespec timeout;
425 struct sockaddr_can addr;
427 unsigned msg_in_progress = 0;
431 for (i=0; i<num_interfaces; i++) {
432 if ((s = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0)
433 error(1, errno, "socket");
435 addr.can_family = AF_CAN;
436 addr.can_ifindex = sock_get_if_index(s, opt.interface[i]);
438 if (i == 0) { /* TX socket */
439 /* disable default receive filter on this RAW socket */
440 /* This is obsolete as we do not read from the socket at all, but for */
441 /* this reason we can remove the receive list in the Kernel to save a */
442 /* little (really a very little!) CPU usage. */
443 if (setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0) == -1)
444 error(1, errno, "SOL_CAN_RAW");
447 if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0)
448 error(1, errno, "bind");
450 const int timestamp_on = 1;
451 if (setsockopt(s, SOL_SOCKET, SO_TIMESTAMPNS,
452 ×tamp_on, sizeof(timestamp_on)) < 0)
453 error(1, errno, "setsockopt SO_TIMESTAMP");
455 const int dropmonitor_on = 1;
456 if (setsockopt(s, SOL_SOCKET, SO_RXQ_OVFL,
457 &dropmonitor_on, sizeof(dropmonitor_on)) < 0)
458 error(1, errno, "setsockopt SO_RXQ_OVFL not supported by your Linux Kernel");
462 pfd[i].events = POLLIN | POLLERR | ((opt.period_us == 0 && !opt.oneattime) ? POLLOUT : 0);
464 pfd[i].events = POLLIN;
467 set_sched_policy_and_prio(SCHED_FIFO, 99);
471 ret = send_frame(pfd[0].fd); \
472 if (ret != sizeof(struct can_frame)) \
473 error(1, errno, "send_frame (line %d)", __LINE__); \
483 while (!finish_flag &&
484 (opt.count == 0 || count < opt.count || msg_in_progress != 0)) {
486 get_next_timeout(&timeout);
487 //printf("ppoll"); fflush(stdout);
488 ret = ppoll(pfd, num_interfaces, &timeout, NULL);
489 //printf("=%d\n", ret);
492 if (!INTERRUPTED_SYSCALL(errno))
493 error(1, errno, "ppoll");
497 if (opt.count == 0 || count < opt.count) {
501 error(1, 0, "poll timeout");
505 if (pfd[0].revents & (POLLIN|POLLERR)) {
506 process_tx(pfd[0].fd);
508 if (pfd[0].revents & POLLOUT) {
509 if (opt.count == 0 || count < opt.count)
514 if (num_interfaces == 3 && pfd[1].revents != 0) {
515 process_on_wire_rx(pfd[1].fd);
519 i = (num_interfaces == 2) ? 1 : 2;
520 if (pfd[i].revents != 0) {
521 process_final_rx(pfd[i].fd);
524 if ((opt.count == 0 || count < opt.count) &&
532 for (i=0; i<num_interfaces; i++)
538 struct poptOption optionsTable[] = {
539 { "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" },
540 { "count", 'c', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.count, 0, "The count of messages to send, zero corresponds to infinity", "num"},
541 { "id", 'i', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.id, 0, "CAN ID of sent messages", "id"},
542 { "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"},
543 { "timeout",'t', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.timeout_ms,0, "Timeout when period is zero", "ms"},
544 { "oneattime",'o', POPT_ARG_NONE, &opt.oneattime,0, "Send the next message only when the previous was finally received"},
545 { "verbose",'v', POPT_ARG_NONE, NULL, 'v', "Send the next message only when the previous was finally received"},
546 { "file", 'f', POPT_ARG_STRING, NULL, 'f', "File where to store results", "filename"},
547 { "histogram", 'h', POPT_ARG_STRING, NULL, 'h', "Store histogram in file", "filename"},
548 { "length", 'l', POPT_ARG_INT|POPT_ARGFLAG_SHOW_DEFAULT, &opt.length, 0, "The length of generated messages", "bytes"},
550 { NULL, 0, 0, NULL, 0 }
553 int parse_options(int argc, const char *argv[])
556 poptContext optCon; /* context for parsing command-line options */
558 optCon = poptGetContext(NULL, argc, argv, optionsTable, 0);
559 //poptSetOtherOptionHelp(optCon, "[OPTIONS]* <port>");
561 /* Now do options processing */
562 while ((c = poptGetNextOpt(optCon)) >= 0) {
568 opt.file = fopen(poptGetOptArg(optCon), "w");
570 error(1, errno, "fopen: %s", poptGetOptArg(optCon));
573 opt.histogram = fopen(poptGetOptArg(optCon), "w");
575 error(1, errno, "fopen: %s", poptGetOptArg(optCon));
580 error(1, 0, "%s: %s\n",
581 poptBadOption(optCon, POPT_BADOPTION_NOALIAS),
584 if (num_interfaces < 2 || num_interfaces > 3)
585 error(1, 0, "-d option must be given exactly 2 or 3 times");
587 if (opt.oneattime && opt.period_us)
588 error(1, 0, "oneattime and period cannot be specified at the same time");
590 poptFreeContext(optCon);
596 int main(int argc, const char *argv[])
602 parse_options(argc, argv);
604 mlockall(MCL_CURRENT | MCL_FUTURE);
606 signal(SIGINT, term_handler);
607 signal(SIGTERM, term_handler);
609 for (i=0; i<MAX_INFOS; i++)
610 msg_infos[i].id = -1;
613 histogram_init(&histogram, 5000000, 1);
616 ret = pipe(completion_pipe);
618 error(1, errno, "pipe");
619 ret = fcntl(completion_pipe[1], F_SETFL, O_NONBLOCK);
621 error(1, errno, "pipe fcntl");
623 pthread_create(&thread, 0, measure_thread, NULL);
625 struct timespec next, now, diff;
626 clock_gettime(CLOCK_MONOTONIC, &next);
628 while (!finish_flag && (opt.count == 0 || completed < opt.count)) {
629 struct pollfd pfd[1];
630 pfd[0].fd = completion_pipe[0];
631 pfd[0].events = POLLIN;
632 ret = poll(pfd, 1, 100);
633 if (ret == -1 && !INTERRUPTED_SYSCALL(errno))
634 error(1, errno, "poll main");
635 if (ret > 0 && (pfd[0].revents & POLLIN)) {
638 ret = read(completion_pipe[0], &mi, sizeof(mi));
639 if (ret < sizeof(mi))
640 error(1, errno, "read completion returned %d", ret);
642 msg_info_print(opt.file, mi);
647 clock_gettime(CLOCK_MONOTONIC, &now);
648 if (timespec_subtract(&diff, &next, &now)) {
649 printf("\rMessage %d", count);
651 next.tv_nsec += 100000000;
652 while (next.tv_nsec >= 1000000000) {
653 next.tv_nsec -= 1000000000;
658 printf("\rMessage %d\n", count);
660 pthread_join(thread, NULL);
662 close(completion_pipe[0]);
663 close(completion_pipe[1]);
666 histogram_fprint(&histogram, opt.histogram);
667 fclose(opt.histogram);