From: Chia-Yu Chang chia-yu.chang@nokia-bell-labs.com
Currently, GRO does not flush packets when the CWR bit is set. A corresponding self-test is being added, in which the CWR flag is set for two consecutive packets, but the first packet with the CWR flag set will not be flushed immediately.
+===================+==========+===============+===========+ | Packet id | CWR flag | Payload | Flushing? | +===================+==========+===============+===========+ | 0 | 0 | PAYLOAD_LEN | 0 | | ... | 0 | PAYLOAD_LEN | 1 | +-------------------+----------+---------------+-----------+ | NUM_PACKETS/2 - 1 | 1 | payload_len | 0 | | NUM_PACKETS/2 | 1 | payload_len | 1 | +-------------------+----------+---------------+-----------+ | ... | 0 | PAYLOAD_LEN | 0 | | NUM_PACKETS | 0 | PAYLOAD_LEN | 1 | +===================+==========+===============+===========+
Signed-off-by: Chia-Yu Chang chia-yu.chang@nokia-bell-labs.com --- tools/testing/selftests/net/gro.c | 80 ++++++++++++++++++++++--------- 1 file changed, 57 insertions(+), 23 deletions(-)
diff --git a/tools/testing/selftests/net/gro.c b/tools/testing/selftests/net/gro.c index cfc39f70635d..50bf1b96ea9d 100644 --- a/tools/testing/selftests/net/gro.c +++ b/tools/testing/selftests/net/gro.c @@ -11,8 +11,8 @@ * 2.ack * Pure ACK does not coalesce. * 3.flags - * Specific test cases: no packets with PSH, SYN, URG, RST set will - * be coalesced. + * Specific test cases: no packets with PSH, SYN, URG, RST, CWR set + * will be coalesced. * 4.tcp * Packets with incorrect checksum, non-consecutive seqno and * different TCP header options shouldn't coalesce. Nit: given that @@ -332,32 +332,57 @@ static void create_packet(void *buf, int seq_offset, int ack_offset, fill_datalinklayer(buf); }
-/* send one extra flag, not first and not last pkt */ -static void send_flags(int fd, struct sockaddr_ll *daddr, int psh, int syn, - int rst, int urg) +#ifndef TH_CWR +#define TH_CWR 0x80 +#endif +static void set_flags(struct tcphdr *tcph, int payload_len, int psh, int syn, + int rst, int urg, int cwr) { - static char flag_buf[MAX_HDR_LEN + PAYLOAD_LEN]; - static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; - int payload_len, pkt_size, flag, i; - struct tcphdr *tcph; - - payload_len = PAYLOAD_LEN * psh; - pkt_size = total_hdr_len + payload_len; - flag = NUM_PACKETS / 2; - - create_packet(flag_buf, flag * payload_len, 0, payload_len, 0); - - tcph = (struct tcphdr *)(flag_buf + tcp_offset); tcph->psh = psh; tcph->syn = syn; tcph->rst = rst; tcph->urg = urg; + if (cwr) + tcph->th_flags |= TH_CWR; + else + tcph->th_flags &= ~TH_CWR; tcph->check = 0; tcph->check = tcp_checksum(tcph, payload_len); +} + +/* send extra flags of the (NUM_PACKETS / 2) and (NUM_PACKETS / 2 - 1) + * pkts, not first and not last pkt + */ +static void send_flags(int fd, struct sockaddr_ll *daddr, int psh, int syn, + int rst, int urg, int cwr) +{ + static char flag_buf[2][MAX_HDR_LEN + PAYLOAD_LEN]; + static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; + int payload_len, pkt_size, i; + struct tcphdr *tcph; + int flag[2]; + + payload_len = PAYLOAD_LEN * (psh || cwr); + pkt_size = total_hdr_len + payload_len; + flag[0] = NUM_PACKETS / 2; + flag[1] = NUM_PACKETS / 2 - 1; + + // Create and configure packets with flags + for (i = 0; i < 2; i++) { + if (flag[i] > 0) { + create_packet(flag_buf[i], flag[i] * payload_len, 0, + payload_len, 0); + tcph = (struct tcphdr *)(flag_buf[i] + tcp_offset); + set_flags(tcph, payload_len, psh, syn, rst, urg, cwr); + } + }
for (i = 0; i < NUM_PACKETS + 1; i++) { - if (i == flag) { - write_packet(fd, flag_buf, pkt_size, daddr); + if (i == flag[0]) { + write_packet(fd, flag_buf[0], pkt_size, daddr); + continue; + } else if (i == flag[1] && cwr) { + write_packet(fd, flag_buf[1], pkt_size, daddr); continue; } create_packet(buf, i * PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); @@ -1020,16 +1045,19 @@ static void gro_sender(void) send_ack(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "flags") == 0) { - send_flags(txfd, &daddr, 1, 0, 0, 0); + send_flags(txfd, &daddr, 1, 0, 0, 0, 0); write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
- send_flags(txfd, &daddr, 0, 1, 0, 0); + send_flags(txfd, &daddr, 0, 1, 0, 0, 0); write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
- send_flags(txfd, &daddr, 0, 0, 1, 0); + send_flags(txfd, &daddr, 0, 0, 1, 0, 0); write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
- send_flags(txfd, &daddr, 0, 0, 0, 1); + send_flags(txfd, &daddr, 0, 0, 0, 1, 0); + write_packet(txfd, fin_pkt, total_hdr_len, &daddr); + + send_flags(txfd, &daddr, 0, 0, 0, 0, 1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "tcp") == 0) { send_changed_checksum(txfd, &daddr); @@ -1163,6 +1191,12 @@ static void gro_receiver(void)
printf("urg flag ends coalescing: "); check_recv_pkts(rxfd, correct_payload, 3); + + correct_payload[0] = PAYLOAD_LEN; + correct_payload[1] = PAYLOAD_LEN * 2; + correct_payload[2] = PAYLOAD_LEN * 2; + printf("cwr flag ends coalescing: "); + check_recv_pkts(rxfd, correct_payload, 3); } else if (strcmp(testname, "tcp") == 0) { correct_payload[0] = PAYLOAD_LEN; correct_payload[1] = PAYLOAD_LEN;