Richard Gobert wrote:
> Added flush id selftests to test different cases where DF flag is set or
> unset and id value changes in the following packets. All cases where the
> packets should coalesce or should not coalesce are tested.
>
> Signed-off-by: Richard Gobert <richardbgobert@xxxxxxxxx>
> ---
> tools/testing/selftests/net/gro.c | 147 ++++++++++++++++++++++++++++++
> 1 file changed, 147 insertions(+)
>
> diff --git a/tools/testing/selftests/net/gro.c b/tools/testing/selftests/net/gro.c
> index 353e1e867fbb..5dc7b539ccbf 100644
> --- a/tools/testing/selftests/net/gro.c
> +++ b/tools/testing/selftests/net/gro.c
> @@ -617,6 +617,123 @@ static void add_ipv6_exthdr(void *buf, void *optpkt, __u8 exthdr_type, char *ext
> iph->payload_len = htons(ntohs(iph->payload_len) + MIN_EXTHDR_SIZE);
> }
>
> +static void fix_ip4_checksum(struct iphdr *iph)
> +{
> + iph->check = 0;
> + iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
> +}
> +
> +static void send_flush_id_case(int fd, struct sockaddr_ll *daddr, int tcase)
> +{
> + static char buf1[MAX_HDR_LEN + PAYLOAD_LEN];
> + static char buf2[MAX_HDR_LEN + PAYLOAD_LEN];
> + static char buf3[MAX_HDR_LEN + PAYLOAD_LEN];
> + bool send_three = false;
> + struct iphdr *iph1;
> + struct iphdr *iph2;
> + struct iphdr *iph3;
> +
> + iph1 = (struct iphdr *)(buf1 + ETH_HLEN);
> + iph2 = (struct iphdr *)(buf2 + ETH_HLEN);
> + iph3 = (struct iphdr *)(buf3 + ETH_HLEN);
> +
> + create_packet(buf1, 0, 0, PAYLOAD_LEN, 0);
> + create_packet(buf2, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
> + create_packet(buf3, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0);
> +
> + switch (tcase) {
> + case 0: /* DF=1, Incrementing - should coalesce */
> + iph1->frag_off |= htons(IP_DF);
> + iph1->id = htons(8);
> + fix_ip4_checksum(iph1);
> +
> + iph2->frag_off |= htons(IP_DF);
> + iph2->id = htons(9);
> + fix_ip4_checksum(iph2);
> + break;
> +
> + case 1: /* DF=1, Fixed - should coalesce */
> + iph1->frag_off |= htons(IP_DF);
> + iph1->id = htons(8);
> + fix_ip4_checksum(iph1);
> +
> + iph2->frag_off |= htons(IP_DF);
> + iph2->id = htons(8);
> + fix_ip4_checksum(iph2);
> + break;
> +
> + case 2: /* DF=0, Incrementing - should coalesce */
> + iph1->frag_off &= ~htons(IP_DF);
> + iph1->id = htons(8);
> + fix_ip4_checksum(iph1);
> +
> + iph2->frag_off &= ~htons(IP_DF);
> + iph2->id = htons(9);
> + fix_ip4_checksum(iph2);
> + break;
> +
> + case 3: /* DF=0, Fixed - should not coalesce */
> + iph1->frag_off &= ~htons(IP_DF);
> + iph1->id = htons(8);
> + fix_ip4_checksum(iph1);
> +
> + iph2->frag_off &= ~htons(IP_DF);
> + iph2->id = htons(8);
> + fix_ip4_checksum(iph2);
> + break;
> +
> + case 4: /* DF=1, two packets incrementing, and one fixed - should
> + * coalesce only the first two packets
> + */
> + iph1->frag_off |= htons(IP_DF);
> + iph1->id = htons(8);
> + fix_ip4_checksum(iph1);
> +
> + iph2->frag_off |= htons(IP_DF);
> + iph2->id = htons(9);
> + fix_ip4_checksum(iph2);
> +
> + iph3->frag_off |= htons(IP_DF);
> + iph3->id = htons(9);
> + fix_ip4_checksum(iph3);
> + send_three = true;
> + break;
> +
> + case 5: /* DF=1, two packets fixed, and one incrementing - should
> + * coalesce only the first two packets
> + */
> + iph1->frag_off |= htons(IP_DF);
> + iph1->id = htons(8);
> + fix_ip4_checksum(iph1);
> +
> + iph2->frag_off |= htons(IP_DF);
> + iph2->id = htons(8);
> + fix_ip4_checksum(iph2);
> +
> + iph3->frag_off |= htons(IP_DF);
> + iph3->id = htons(9);
> + fix_ip4_checksum(iph3);
> + send_three = true;
> + break;
> + }
Consider moving the fix_ip4_checksum calls out of the switch to reduce
duplication.
> +
> + write_packet(fd, buf1, total_hdr_len + PAYLOAD_LEN, daddr);
> + write_packet(fd, buf2, total_hdr_len + PAYLOAD_LEN, daddr);
> +
> + if (send_three)
> + write_packet(fd, buf3, total_hdr_len + PAYLOAD_LEN, daddr);
> +}
> +
> +static void test_flush_id(int fd, struct sockaddr_ll *daddr, char *fin_pkt)
> +{
> + for (int i = 0; i < 6; i++) {
Please avoid unnamed magic constants. Something like
const int num_flush_id_cases = 6; /* See switch in send_flush_id_case */
Or even define an enum with named tests and and _MAX val. It's
verbose, but helpful to readers.
> + sleep(1);
> + send_flush_id_case(fd, daddr, i);
> + sleep(1);
> + write_packet(fd, fin_pkt, total_hdr_len, daddr);
> + }
> +}
> +
