This patch adds txtime support to xdp_hw_metadata. User can configure the delta of HW txtime to HW RX-time by using "-l" argument. The default delta is set to 1 second.
This patch is tested with stmmac on Intel Tiger Lake platform. Refer to result below, the delta between pre-determined ETF txtime and actual HW transmit complete time is around 24 us.
$ sudo ./xdp_hw_metadata eth0 ... xsk_ring_cons__peek: 1 0x55fcb80ce7a8: rx_desc[0]->addr=80100 addr=80100 comp_addr=80100 EoP No rx_hash err=-95 HW RX-time: 1677764507059055964 (sec:1677764507.0591) delta to User RX-time sec:0.0002 (237.548 usec) XDP RX-time: 1677764507059280741 (sec:1677764507.0593) delta to User RX-time sec:0.0000 (12.771 usec) 0x55fcb80ce7a8: ping-pong with csum=5619 (want 8626) csum_start=34 csum_offset=6 HW RX-time: 1677764507059055964 (sec:1677764507.0591) delta to HW Txtime sec:1.0000 (1000000.000 usec) 0x55fcb80ce7a8: complete tx idx=0 addr=18 HW Txtime: 1677764508059055964 (sec:1677764508.0591) delta to HW TX-complete-time sec:0.0000 (24.235 usec) HW TX-complete-time: 1677764508059080199 (sec:1677764508.0591) delta to User TX-complete-time sec:0.0054 (5423.263 usec) XDP RX-time: 1677764507059280741 (sec:1677764507.0593) delta to User TX-complete-time sec:1.0052 (1005222.721 usec) HW RX-time: 1677764507059055964 (sec:1677764507.0591) delta to HW TX-complete-time sec:1.0000 (1000024.235 usec) 0x55fcb80ce7a8: complete rx idx=128 addr=80100
$ sudo ./xdp_hw_metadata eth0 -l 10000000 ... xsk_ring_cons__peek: 1 0x5626d54de7a8: rx_desc[0]->addr=80100 addr=80100 comp_addr=80100 EoP No rx_hash err=-95 HW RX-time: 1677764655807717783 (sec:1677764655.8077) delta to User RX-time sec:0.0002 (240.571 usec) XDP RX-time: 1677764655807942983 (sec:1677764655.8079) delta to User RX-time sec:0.0000 (15.371 usec) 0x5626d54de7a8: ping-pong with csum=5619 (want 8626) csum_start=34 csum_offset=6 HW RX-time: 1677764655807717783 (sec:1677764655.8077) delta to HW Txtime sec:0.0100 (10000.000 usec) 0x5626d54de7a8: complete tx idx=0 addr=18 HW Txtime: 1677764655817717783 (sec:1677764655.8177) delta to HW TX-complete-time sec:0.0000 (23.965 usec) HW TX-complete-time: 1677764655817741748 (sec:1677764655.8177) delta to User TX-complete-time sec:0.0003 (291.792 usec) XDP RX-time: 1677764655807942983 (sec:1677764655.8079) delta to User TX-complete-time sec:0.0101 (10090.557 usec) HW RX-time: 1677764655807717783 (sec:1677764655.8077) delta to HW TX-complete-time sec:0.0100 (10023.965 usec) 0x5626d54de7a8: complete rx idx=128 addr=80100
Signed-off-by: Song Yoong Siang yoong.siang.song@intel.com --- tools/testing/selftests/bpf/xdp_hw_metadata.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c index 3291625ba4fb..e9c3e29dc538 100644 --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c @@ -13,6 +13,7 @@ * - UDP 9091 packets trigger TX reply * - TX HW timestamp is requested and reported back upon completion * - TX checksum is requested + * - HW txtime is set for transmission */
#include <test_progs.h> @@ -61,6 +62,8 @@ int rxq; bool skip_tx; __u64 last_hw_rx_timestamp; __u64 last_xdp_rx_timestamp; +__u64 last_txtime; +__u64 txtime_delta_to_hw_rx_timestamp = 1000000000; /* 1 second */
void test__fail(void) { /* for network_helpers.c */ }
@@ -274,6 +277,8 @@ static bool complete_tx(struct xsk *xsk, clockid_t clock_id) if (meta->completion.tx_timestamp) { __u64 ref_tstamp = gettime(clock_id);
+ print_tstamp_delta("HW Txtime", "HW TX-complete-time", + last_txtime, meta->completion.tx_timestamp); print_tstamp_delta("HW TX-complete-time", "User TX-complete-time", meta->completion.tx_timestamp, ref_tstamp); print_tstamp_delta("XDP RX-time", "User TX-complete-time", @@ -371,6 +376,13 @@ static void ping_pong(struct xsk *xsk, void *rx_packet, clockid_t clock_id) xsk, ntohs(udph->check), ntohs(want_csum), meta->request.csum_start, meta->request.csum_offset);
+ /* Set txtime for Earliest TxTime First (ETF) */ + meta->flags |= XDP_TXMD_FLAGS_TXTIME; + meta->request.txtime = last_hw_rx_timestamp + txtime_delta_to_hw_rx_timestamp; + last_txtime = meta->request.txtime; + print_tstamp_delta("HW RX-time", "HW Txtime", last_hw_rx_timestamp, + meta->request.txtime); + memcpy(data, rx_packet, len); /* don't share umem chunk for simplicity */ tx_desc->options |= XDP_TX_METADATA; tx_desc->len = len; @@ -595,6 +607,7 @@ static void print_usage(void) " -h Display this help and exit\n\n" " -m Enable multi-buffer XDP for larger MTU\n" " -r Don't generate AF_XDP reply (rx metadata only)\n" + " -l Delta of HW Txtime to HW RX-time in ns (default: 1s)\n" "Generate test packets on the other machine with:\n" " echo -n xdp | nc -u -q1 <dst_ip> 9091\n";
@@ -605,7 +618,7 @@ static void read_args(int argc, char *argv[]) { int opt;
- while ((opt = getopt(argc, argv, "chmr")) != -1) { + while ((opt = getopt(argc, argv, "chmrl:")) != -1) { switch (opt) { case 'c': bind_flags &= ~XDP_USE_NEED_WAKEUP; @@ -621,6 +634,9 @@ static void read_args(int argc, char *argv[]) case 'r': skip_tx = true; break; + case 'l': + txtime_delta_to_hw_rx_timestamp = atoll(optarg); + break; case '?': if (isprint(optopt)) fprintf(stderr, "Unknown option: -%c\n", optopt);