In current ping-pong design, xdp_hw_metadata will wait until the packet
transmission completely done, then only start to receive the next packet.
The current sleep interval is 10ms, which is unnecessary large. Typically,
a NIC does not need such a long time to transmit a packet. Furthermore,
during this 10ms sleep time, the app is unable to receive incoming packets.
Therefore, this commit reduce sleep interval to 10us, so that
xdp_hw_metadata is able to support periodic packets with shorter interval.
10us * 500 = 5ms should be enough for packet transmission and status
retrieval.
Signed-off-by: Song Yoong Siang <yoong.siang.song@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20240303083225.1184165-2-yoong.siang.song@intel.com
Add VLAN hint to the xdp_hw_metadata program.
Also, to make metadata layout more straightforward, add flags field
to pass information about validity of every separate hint separately.
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://lore.kernel.org/r/20231205210847.28460-17-larysa.zaremba@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When compiling BPF selftests with RELEASE=1, we get two new
warnings, which are treated as errors. Fix them.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20231212225343.1723081-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When we get a packet on port 9091, we swap src/dst and send it out.
At this point we also request the timestamp and checksum offloads.
Checksum offload is verified by looking at the tcpdump on the other side.
The tool prints pseudo-header csum and the final one it expects.
The final checksum actually matches the incoming packets checksum
because we only flip the src/dst and don't change the payload.
Some other related changes:
- switched to zerocopy mode by default; new flag can be used to force
old behavior
- request fixed tx_metadata_len headroom
- some other small fixes (umem size, fill idx+i, etc)
mvbz3:~# ./xdp_hw_metadata eth3
...
xsk_ring_cons__peek: 1
0x19546f8: rx_desc[0]->addr=80100 addr=80100 comp_addr=80100
rx_hash: 0x80B7EA8B with RSS type:0x2A
rx_timestamp: 1697580171852147395 (sec:1697580171.8521)
HW RX-time: 1697580171852147395 (sec:1697580171.8521), delta to User RX-time sec:0.2797 (279673.082 usec)
XDP RX-time: 1697580172131699047 (sec:1697580172.1317), delta to User RX-time sec:0.0001 (121.430 usec)
0x19546f8: ping-pong with csum=3b8e (want d862) csum_start=54 csum_offset=6
0x19546f8: complete tx idx=0 addr=8
tx_timestamp: 1697580172056756493 (sec:1697580172.0568)
HW TX-complete-time: 1697580172056756493 (sec:1697580172.0568), delta to User TX-complete-time sec:0.0852 (85175.537 usec)
XDP RX-time: 1697580172131699047 (sec:1697580172.1317), delta to User TX-complete-time sec:0.0102 (10232.983 usec)
HW RX-time: 1697580171852147395 (sec:1697580171.8521), delta to HW TX-complete-time sec:0.2046 (204609.098 usec)
0x19546f8: complete rx idx=128 addr=80100
mvbz4:~# nc -Nu -q1 ${MVBZ3_LINK_LOCAL_IP}%eth3 9091
mvbz4:~# tcpdump -vvx -i eth3 udp
tcpdump: listening on eth3, link-type EN10MB (Ethernet), snapshot length 262144 bytes
12:26:09.301074 IP6 (flowlabel 0x35fa5, hlim 127, next-header UDP (17) payload length: 11) fe80::1270:fdff:fe48:1087.55807 > fe80::1270:fdff:fe48:1077.9091: [bad udp cksum 0x3b8e -> 0xde7e!] UDP, length 3
0x0000: 6003 5fa5 000b 117f fe80 0000 0000 0000
0x0010: 1270 fdff fe48 1087 fe80 0000 0000 0000
0x0020: 1270 fdff fe48 1077 d9ff 2383 000b 3b8e
0x0030: 7864 70
12:26:09.301976 IP6 (flowlabel 0x35fa5, hlim 127, next-header UDP (17) payload length: 11) fe80::1270:fdff:fe48:1077.9091 > fe80::1270:fdff:fe48:1087.55807: [udp sum ok] UDP, length 3
0x0000: 6003 5fa5 000b 117f fe80 0000 0000 0000
0x0010: 1270 fdff fe48 1077 fe80 0000 0000 0000
0x0020: 1270 fdff fe48 1087 2383 d9ff 000b de7e
0x0030: 7864 70
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231127190319.1190813-14-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This is the recommended way to run AF_XDP, so let's use it in the test.
Also, some unrelated changes to now blow up the log too much:
- change default mode to zerocopy and add -c to use copy mode
- small fixes for the flags/sizes/prints
- add print_tstamp_delta to print timestamp + reference
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231127190319.1190813-13-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There are architectures where char is not signed. If so, the following
error is triggered:
| xdp_hw_metadata.c:435:42: error: result of comparison of constant -1 \
| with expression of type 'char' is always true \
| [-Werror,-Wtautological-constant-out-of-range-compare]
| 435 | while ((opt = getopt(argc, argv, "mh")) != -1) {
| | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~
| 1 error generated.
Correct by changing the char to int.
Fixes: bb6a88885f ("selftests/bpf: Add options and frags to xdp_hw_metadata")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Larysa Zaremba <larysa.zaremba@intel.com>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Link: https://lore.kernel.org/r/20231102103537.247336-1-bjorn@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This is a follow-up to the commit 9b2b86332a ("bpf: Allow to use kfunc
XDP hints and frags together").
The are some possible implementations problems that may arise when providing
metadata specifically for multi-buffer packets, therefore there must be a
possibility to test such option separately.
Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
program as capable to use frags.
As for now, xdp_hw_metadata accepts no options, so add simple option
parsing logic and a help message.
For quick reference, also add an ingress packet generation command to the
help message. The command comes from [0].
Example of output for multi-buffer packet:
xsk_ring_cons__peek: 1
0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
rx_hash: 0x5789FCBB with RSS type:0x29
rx_timestamp: 1696856851535324697 (sec:1696856851.5353)
XDP RX-time: 1696856843158256391 (sec:1696856843.1583)
delta sec:-8.3771 (-8377068.306 usec)
AF_XDP time: 1696856843158413078 (sec:1696856843.1584)
delta sec:0.0002 (156.687 usec)
0xead018: complete idx=23 addr=f000
xsk_ring_cons__peek: 1
0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
0xead018: complete idx=24 addr=8000
xsk_ring_cons__peek: 1
0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
0xead018: complete idx=25 addr=9000
Metadata is printed for the first packet only.
[0] https://lore.kernel.org/all/20230119221536.3349901-18-sdf@google.com/
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20231017162800.24080-1-larysa.zaremba@intel.com
Fix a bunch of potentially unitialized variable usage warnings that are
reported by GCC in -O2 mode. Also silence overzealous stringop-truncation
class of warnings.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20231006175744.3136675-1-andrii@kernel.org
To correlate the hardware RX timestamp with something, add tracking of
two software timestamps both clock source CLOCK_TAI (see description in
man clock_gettime(2)).
XDP metadata is extended with xdp_timestamp for capturing when XDP
received the packet. Populated with BPF helper bpf_ktime_get_tai_ns(). I
could not find a BPF helper for getting CLOCK_REALTIME, which would have
been preferred. In userspace when AF_XDP sees the packet another
software timestamp is recorded via clock_gettime() also clock source
CLOCK_TAI.
Example output shortly after loading igc driver:
poll: 1 (0) skip=1 fail=0 redir=2
xsk_ring_cons__peek: 1
0x12557a8: rx_desc[1]->addr=100000000009000 addr=9100 comp_addr=9000
rx_hash: 0x82A96531 with RSS type:0x1
rx_timestamp: 1681740540304898909 (sec:1681740540.3049)
XDP RX-time: 1681740577304958316 (sec:1681740577.3050) delta sec:37.0001 (37000059.407 usec)
AF_XDP time: 1681740577305051315 (sec:1681740577.3051) delta sec:0.0001 (92.999 usec)
0x12557a8: complete idx=9 addr=9000
The first observation is that the 37 sec difference between RX HW vs XDP
timestamps, which indicate hardware is likely clock source
CLOCK_REALTIME, because (as of this writing) CLOCK_TAI is initialised
with a 37 sec offset.
The 93 usec (microsec) difference between XDP vs AF_XDP userspace is the
userspace wakeup time. On this hardware it was caused by CPU idle sleep
states, which can be reduced by tuning /dev/cpu_dma_latency.
View current requested/allowed latency bound via:
hexdump --format '"%d\n"' /dev/cpu_dma_latency
More explanation of the output and how this can be used to identify
clock drift for the HW clock can be seen here[1]:
[1] https://github.com/xdp-project/xdp-project/blob/master/areas/hints/xdp_hints_kfuncs02_driver_igc.org
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Yoong Siang <yoong.siang.song@intel.com>
Link: https://lore.kernel.org/bpf/168182466298.616355.2544377890818617459.stgit@firesoul
Update BPF selftests to use the new RSS type argument for kfunc
bpf_xdp_metadata_rx_hash.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/168132894068.340624.8914711185697163690.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The tool xdp_hw_metadata can be used by driver developers
implementing XDP-hints metadata kfuncs.
Remove all bpf_printk calls, as the tool already transfers all the
XDP-hints related information via metadata area to AF_XDP
userspace process.
Add counters for providing remaining information about failure and
skipped packet events.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/168132891533.340624.7313781245316405141.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The linux/net_tstamp.h is included more than once, thus clean it up.
Signed-off-by: Ye Xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/202301311440516312161@zte.com.cn
The ifname char pointer is taken directly from the command line
as input and the string is copied directly into struct ifreq
via strcpy. This makes it easy to corrupt other members of ifreq
and generally do stack overflows.
Most often the ioctl will fail with:
./xdp_hw_metadata: ioctl(SIOCETHTOOL): Bad address
As people will likely copy-paste code for getting NIC queue
channels (rxq_num) and enabling HW timestamping (hwtstamp_ioctl)
lets make this code a bit more secure by using strncpy.
Fixes: 297a3f1241 ("selftests/bpf: Simple program to dump XDP RX metadata")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/167527272543.937063.16993147790832546209.stgit@firesoul
The glibc error reporting function error():
void error(int status, int errnum, const char *format, ...);
The status argument should be a positive value between 0-255 as it
is passed over to the exit(3) function as the value as the shell exit
status. The least significant byte of status (i.e., status & 0xFF) is
returned to the shell parent.
Fix this by using 1 instead of -1. As 1 corresponds to C standard
constant EXIT_FAILURE.
Fixes: 297a3f1241 ("selftests/bpf: Simple program to dump XDP RX metadata")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/167527272038.937063.9137108142012298120.stgit@firesoul
Using xdp_hw_metadata I experince Segmentation fault after seeing
"detaching bpf program....".
On my system the segfault happened when accessing bpf_obj->skeleton
in xdp_hw_metadata__destroy(bpf_obj) call. That doesn't make any sense
as this memory have not been freed by program at this point in time.
Prior to calling xdp_hw_metadata__destroy(bpf_obj) the function
close_xsk() is called for each RX-queue xsk. The real bug lays
in close_xsk() that unmap via munmap() the wrong memory pointer.
The call xsk_umem__delete(xsk->umem) will free xsk->umem, thus
the call to munmap(xsk->umem, UMEM_SIZE) will have unpredictable
behavior. And man page explain subsequent references to these
pages will generate SIGSEGV.
Unmapping xsk->umem_area instead removes the segfault.
Fixes: 297a3f1241 ("selftests/bpf: Simple program to dump XDP RX metadata")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/167527271533.937063.5717065138099679142.stgit@firesoul
The existing timestamping_enable() is a no-op because it applies
to the socket-related path that we are not verifying here
anymore. (but still leaving the code around hoping we can
have xdp->skb path verified here as well)
poll: 1 (0)
xsk_ring_cons__peek: 1
0xf64788: rx_desc[0]->addr=100000000008000 addr=8100 comp_addr=8000
rx_hash: 3697961069
rx_timestamp: 1674657672142214773 (sec:1674657672.1422)
XDP RX-time: 1674657709561774876 (sec:1674657709.5618) delta sec:37.4196
AF_XDP time: 1674657709561871034 (sec:1674657709.5619) delta
sec:0.0001 (96.158 usec)
0xf64788: complete idx=8 addr=8000
Also, maybe something to archive here, see [0] for Jesper's note
about NIC vs host clock delta.
0: https://lore.kernel.org/bpf/f3a116dc-1b14-3432-ad20-a36179ef0608@redhat.com/
v2:
- Restore original value (Martin)
Fixes: 297a3f1241 ("selftests/bpf: Simple program to dump XDP RX metadata")
Reported-by: Jesper Dangaard Brouer <jbrouer@redhat.com>
Tested-by: Jesper Dangaard Brouer <jbrouer@redhat.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230126225030.510629-1-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
To be used for verification of driver implementations. Note that
the skb path is gone from the series, but I'm still keeping the
implementation for any possible future work.
$ xdp_hw_metadata <ifname>
On the other machine:
$ echo -n xdp | nc -u -q1 <target> 9091 # for AF_XDP
$ echo -n skb | nc -u -q1 <target> 9092 # for skb
Sample output:
# xdp
xsk_ring_cons__peek: 1
0x19f9090: rx_desc[0]->addr=100000000008000 addr=8100 comp_addr=8000
rx_timestamp_supported: 1
rx_timestamp: 1667850075063948829
0x19f9090: complete idx=8 addr=8000
# skb
found skb hwtstamp = 1668314052.854274681
Decoding:
# xdp
rx_timestamp=1667850075.063948829
$ date -d @1667850075
Mon Nov 7 11:41:15 AM PST 2022
$ date
Mon Nov 7 11:42:05 AM PST 2022
# skb
$ date -d @1668314052
Sat Nov 12 08:34:12 PM PST 2022
$ date
Sat Nov 12 08:37:06 PM PST 2022
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-18-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Song Yoong Siang