2019.05.08 v3:
- reuse existing infrastructure as much as possible
- remove j1939_pktinfo and cmsg support for sendmsg
With this version we started to use skb->tskey as send() counter.
No more cookies is needed. So, we can get proper session ID even with
write()/send() and sendto(). The errorqueue will return empty skb with
multiple attached optional CMSG. Here is an example of parsing attached
CMSGs:
ret = recvmsg(priv->sock, &msg, MSG_ERRQUEUE);
...
for (cm = CMSG_FIRSTHDR(&msg);
cm && cm->cmsg_len;
cm = CMSG_NXTHDR(&msg, cm)) {
if (cm->cmsg_level == SOL_SOCKET &&
cm->cmsg_type == SCM_TIMESTAMPING) {
tss = (void *)CMSG_DATA(cm);
} else if (cm->cmsg_level == SOL_SOCKET && cm->cmsg_type == SCM_TIMESTAMPING_OPT_STATS) {
void *jstats = (void *)CMSG_DATA(cm);
jcat_scm_opt_stats(priv, jstats, cm->cmsg_len - hdr_len, &send);
} else if (cm->cmsg_level == SOL_CAN_J1939 && cm->cmsg_type == SCM_J1939_ERRQUEUE) {
serr = (void *)CMSG_DATA(cm);
} else
warnx("serr: not supported type: %d.%d",
cm->cmsg_level, cm->cmsg_type);
if (serr && tss) {
if (serr->ee_origin == SO_EE_ORIGIN_TIMESTAMPING) { // für den ACK
if (serr->ee_errno != ENOMSG)
warnx("serr: tx error: %i, %s", serr->ee_errno,
strerror(serr->ee_errno));
print_timestamp(tss, serr->ee_info,
serr->ee_data, send);
return serr->ee_info == SCM_TSTAMP_SCHED ? -EINTR : 0;
} else if (serr->ee_origin == SO_EE_ORIGIN_LOCAL) { // für err
if (serr->ee_info != J1939_EE_INFO_TX_ABORT)
warnx("serr: unknown ee_info: %i", serr->ee_info);
__print_timestamp(" ABORT", &tss->ts[0], serr->ee_data, send);
warnx("serr: tx error: %i, %s", serr->ee_errno,
strerror(serr->ee_errno));
return serr->ee_errno;
} else
error(1, 0, "serr: wrong origin: %u", serr->ee_origin);
}
Here is an example output of jcat command:
root@DistroKit:~ jcat -i /test_100k can0:0x80 :0x90,0x12300
ENQ: 1551398572 s 888773 us (seq=0, send=1764)
ENQ: 1551398573 s 353498 us (seq=0, send=3549)
ENQ: 1551398573 s 818241 us (seq=0, send=5334)
ENQ: 1551398574 s 282923 us (seq=0, send=7119)
ENQ: 1551398574 s 793238 us (seq=0, send=8904)
ENQ: 1551398575 s 353244 us (seq=0, send=10689)
ENQ: 1551398575 s 817879 us (seq=0, send=12474)
ENQ: 1551398576 s 313210 us (seq=0, send=14259)
ENQ: 1551398576 s 777841 us (seq=0, send=16044)
ENQ: 1551398577 s 242604 us (seq=0, send=17829)
ENQ: 1551398577 s 707297 us (seq=0, send=19614)
ENQ: 1551398578 s 172032 us (seq=0, send=21399)
ENQ: 1551398578 s 636739 us (seq=0, send=23184)
ENQ: 1551398579 s 193257 us (seq=0, send=24969)
ENQ: 1551398579 s 657871 us (seq=0, send=26754)
ENQ: 1551398580 s 540311 us (seq=0, send=28539)
ENQ: 1551398581 s 4942 us (seq=0, send=30324)
.....
ENQ: 1551398599 s 193025 us (seq=0, send=89229)
ENQ: 1551398599 s 673031 us (seq=0, send=91014)
ENQ: 1551398600 s 137643 us (seq=0, send=92799)
ENQ: 1551398600 s 602364 us (seq=0, send=94584)
ENQ: 1551398601 s 66971 us (seq=0, send=96369)
ENQ: 1551398601 s 531581 us (seq=0, send=98154)
ENQ: 1551398601 s 996315 us (seq=0, send=99939)
ENQ: 1551398602 s 460958 us (seq=0, send=101724)
ENQ: 1551398602 s 624222 us (seq=0, send=102354)
ACK: 1551398602 s 628892 us (seq=0, send=102400)
ENQ - means, some or all packets was queued and the stack is
waiting until the queue have more space or we get an ACK.
ACK - (E)TP the session was completed without any error.
amount of send bytes is attached in to netlink compatible CMSG and
can be extended without braking compatibility..
2019.04.27 v2:
- make MSG_ERRQUEUE optional and disabled by default
- init info struct in sendmsg
- add verbose TX status support.
2019.04.25 v1:
deprecated description was removed.
Oleksij Rempel (3):
j1939: transport: store error in to session
j1939: add MSG_ERRQUEUE support
j1939: check supported recv*() flags
include/uapi/linux/can/j1939.h | 12 ++++
net/can/j1939/j1939-priv.h | 12 ++++
net/can/j1939/socket.c | 103 ++++++++++++++++++++++++++++++++-
net/can/j1939/transport.c | 14 ++++-
4 files changed, 137 insertions(+), 4 deletions(-)
--
2.20.1
