* [PATCH net-next v3 2/3] net: gro: parse ipv6 ext headers without frag0 invalidation
2024-01-03 14:36 [PATCH net-next v3 0/3] net: gro: reduce extension header parsing overhead Richard Gobert
2024-01-03 14:40 ` [PATCH net-next v3 1/3] net: gso: add HBH extension header offload support Richard Gobert
@ 2024-01-03 14:44 ` Richard Gobert
2024-01-03 16:46 ` Eric Dumazet
2024-01-03 14:48 ` [PATCH net-next v3 3/3] selftests/net: fix GRO coalesce test and add ext header coalesce tests Richard Gobert
2024-01-05 16:20 ` [PATCH net-next v3 0/3] net: gro: reduce extension header parsing overhead patchwork-bot+netdevbpf
3 siblings, 1 reply; 6+ messages in thread
From: Richard Gobert @ 2024-01-03 14:44 UTC (permalink / raw)
To: davem, dsahern, edumazet, kuba, pabeni, shuah, netdev,
linux-kernel, linux-kselftest
The existing code always pulls the IPv6 header and sets the transport
offset initially. Then optionally again pulls any extension headers in
ipv6_gso_pull_exthdrs and sets the transport offset again on return from
that call. skb->data is set at the start of the first extension header
before calling ipv6_gso_pull_exthdrs, and must disable the frag0
optimization because that function uses pskb_may_pull/pskb_pull instead of
skb_gro_ helpers. It sets the GRO offset to the TCP header with
skb_gro_pull and sets the transport header. Then returns skb->data to its
position before this block.
This commit introduces a new helper function - ipv6_gro_pull_exthdrs -
which is used in ipv6_gro_receive to pull ipv6 ext headers instead of
ipv6_gso_pull_exthdrs. Thus, there is no modification of skb->data, all
operations use skb_gro_* helpers, and the frag0 fast path can be taken for
IPv6 packets with ext headers.
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
---
net/ipv6/ip6_offload.c | 51 +++++++++++++++++++++++++++++++++---------
1 file changed, 41 insertions(+), 10 deletions(-)
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 0e0b5fed0995..cca64c7809be 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -37,6 +37,40 @@
INDIRECT_CALL_L4(cb, f2, f1, head, skb); \
})
+static int ipv6_gro_pull_exthdrs(struct sk_buff *skb, int off, int proto)
+{
+ const struct net_offload *ops = NULL;
+ struct ipv6_opt_hdr *opth;
+
+ for (;;) {
+ int len;
+
+ ops = rcu_dereference(inet6_offloads[proto]);
+
+ if (unlikely(!ops))
+ break;
+
+ if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
+ break;
+
+ opth = skb_gro_header(skb, off + sizeof(*opth), off);
+ if (unlikely(!opth))
+ break;
+
+ len = ipv6_optlen(opth);
+
+ opth = skb_gro_header(skb, off + len, off);
+ if (unlikely(!opth))
+ break;
+ proto = opth->nexthdr;
+
+ off += len;
+ }
+
+ skb_gro_pull(skb, off - skb_network_offset(skb));
+ return proto;
+}
+
static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
{
const struct net_offload *ops = NULL;
@@ -203,28 +237,25 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
goto out;
skb_set_network_header(skb, off);
- skb_gro_pull(skb, sizeof(*iph));
- skb_set_transport_header(skb, skb_gro_offset(skb));
- flush += ntohs(iph->payload_len) != skb_gro_len(skb);
+ flush += ntohs(iph->payload_len) != skb->len - hlen;
proto = iph->nexthdr;
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive) {
- pskb_pull(skb, skb_gro_offset(skb));
- skb_gro_frag0_invalidate(skb);
- proto = ipv6_gso_pull_exthdrs(skb, proto);
- skb_gro_pull(skb, -skb_transport_offset(skb));
- skb_reset_transport_header(skb);
- __skb_push(skb, skb_gro_offset(skb));
+ proto = ipv6_gro_pull_exthdrs(skb, hlen, proto);
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive)
goto out;
- iph = ipv6_hdr(skb);
+ iph = skb_gro_network_header(skb);
+ } else {
+ skb_gro_pull(skb, sizeof(*iph));
}
+ skb_set_transport_header(skb, skb_gro_offset(skb));
+
NAPI_GRO_CB(skb)->proto = proto;
flush--;
--
2.36.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net-next v3 3/3] selftests/net: fix GRO coalesce test and add ext header coalesce tests
2024-01-03 14:36 [PATCH net-next v3 0/3] net: gro: reduce extension header parsing overhead Richard Gobert
2024-01-03 14:40 ` [PATCH net-next v3 1/3] net: gso: add HBH extension header offload support Richard Gobert
2024-01-03 14:44 ` [PATCH net-next v3 2/3] net: gro: parse ipv6 ext headers without frag0 invalidation Richard Gobert
@ 2024-01-03 14:48 ` Richard Gobert
2024-01-05 16:20 ` [PATCH net-next v3 0/3] net: gro: reduce extension header parsing overhead patchwork-bot+netdevbpf
3 siblings, 0 replies; 6+ messages in thread
From: Richard Gobert @ 2024-01-03 14:48 UTC (permalink / raw)
To: davem, dsahern, edumazet, kuba, pabeni, shuah, netdev,
linux-kernel, linux-kselftest
Currently there is no test which checks that IPv6 extension header packets
successfully coalesce. This commit adds a test, which verifies two IPv6
packets with HBH extension headers do coalesce, and another test which
checks that packets with different extension header data do not coalesce
in GRO.
I changed the receive socket filter to accept a packet with one extension
header. This change exposed a bug in the fragment test -- the old BPF did
not accept the fragment packet. I updated correct_num_packets in the
fragment test accordingly.
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
---
tools/testing/selftests/net/gro.c | 93 +++++++++++++++++++++++++++++--
1 file changed, 87 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/net/gro.c b/tools/testing/selftests/net/gro.c
index 30024d0ed373..353e1e867fbb 100644
--- a/tools/testing/selftests/net/gro.c
+++ b/tools/testing/selftests/net/gro.c
@@ -71,6 +71,12 @@
#define MAX_PAYLOAD (IP_MAXPACKET - sizeof(struct tcphdr) - sizeof(struct ipv6hdr))
#define NUM_LARGE_PKT (MAX_PAYLOAD / MSS)
#define MAX_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
+#define MIN_EXTHDR_SIZE 8
+#define EXT_PAYLOAD_1 "\x00\x00\x00\x00\x00\x00"
+#define EXT_PAYLOAD_2 "\x11\x11\x11\x11\x11\x11"
+
+#define ipv6_optlen(p) (((p)->hdrlen+1) << 3) /* calculate IPv6 extension header len */
+#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
static const char *addr6_src = "fdaa::2";
static const char *addr6_dst = "fdaa::1";
@@ -104,7 +110,7 @@ static void setup_sock_filter(int fd)
const int dport_off = tcp_offset + offsetof(struct tcphdr, dest);
const int ethproto_off = offsetof(struct ethhdr, h_proto);
int optlen = 0;
- int ipproto_off;
+ int ipproto_off, opt_ipproto_off;
int next_off;
if (proto == PF_INET)
@@ -116,14 +122,30 @@ static void setup_sock_filter(int fd)
if (strcmp(testname, "ip") == 0) {
if (proto == PF_INET)
optlen = sizeof(struct ip_timestamp);
- else
- optlen = sizeof(struct ip6_frag);
+ else {
+ BUILD_BUG_ON(sizeof(struct ip6_hbh) > MIN_EXTHDR_SIZE);
+ BUILD_BUG_ON(sizeof(struct ip6_dest) > MIN_EXTHDR_SIZE);
+ BUILD_BUG_ON(sizeof(struct ip6_frag) > MIN_EXTHDR_SIZE);
+
+ /* same size for HBH and Fragment extension header types */
+ optlen = MIN_EXTHDR_SIZE;
+ opt_ipproto_off = ETH_HLEN + sizeof(struct ipv6hdr)
+ + offsetof(struct ip6_ext, ip6e_nxt);
+ }
}
+ /* this filter validates the following:
+ * - packet is IPv4/IPv6 according to the running test.
+ * - packet is TCP. Also handles the case of one extension header and then TCP.
+ * - checks the packet tcp dport equals to DPORT. Also handles the case of one
+ * extension header and then TCP.
+ */
struct sock_filter filter[] = {
BPF_STMT(BPF_LD + BPF_H + BPF_ABS, ethproto_off),
- BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ntohs(ethhdr_proto), 0, 7),
+ BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ntohs(ethhdr_proto), 0, 9),
BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ipproto_off),
+ BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_TCP, 2, 0),
+ BPF_STMT(BPF_LD + BPF_B + BPF_ABS, opt_ipproto_off),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_TCP, 0, 5),
BPF_STMT(BPF_LD + BPF_H + BPF_ABS, dport_off),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DPORT, 2, 0),
@@ -576,6 +598,39 @@ static void add_ipv4_ts_option(void *buf, void *optpkt)
iph->check = checksum_fold(iph, sizeof(struct iphdr) + optlen, 0);
}
+static void add_ipv6_exthdr(void *buf, void *optpkt, __u8 exthdr_type, char *ext_payload)
+{
+ struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr *)(optpkt + tcp_offset);
+ struct ipv6hdr *iph = (struct ipv6hdr *)(optpkt + ETH_HLEN);
+ char *exthdr_payload_start = (char *)(exthdr + 1);
+
+ exthdr->hdrlen = 0;
+ exthdr->nexthdr = IPPROTO_TCP;
+
+ memcpy(exthdr_payload_start, ext_payload, MIN_EXTHDR_SIZE - sizeof(*exthdr));
+
+ memcpy(optpkt, buf, tcp_offset);
+ memcpy(optpkt + tcp_offset + MIN_EXTHDR_SIZE, buf + tcp_offset,
+ sizeof(struct tcphdr) + PAYLOAD_LEN);
+
+ iph->nexthdr = exthdr_type;
+ iph->payload_len = htons(ntohs(iph->payload_len) + MIN_EXTHDR_SIZE);
+}
+
+static void send_ipv6_exthdr(int fd, struct sockaddr_ll *daddr, char *ext_data1, char *ext_data2)
+{
+ static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
+ static char exthdr_pck[sizeof(buf) + MIN_EXTHDR_SIZE];
+
+ create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
+ add_ipv6_exthdr(buf, exthdr_pck, IPPROTO_HOPOPTS, ext_data1);
+ write_packet(fd, exthdr_pck, total_hdr_len + PAYLOAD_LEN + MIN_EXTHDR_SIZE, daddr);
+
+ create_packet(buf, PAYLOAD_LEN * 1, 0, PAYLOAD_LEN, 0);
+ add_ipv6_exthdr(buf, exthdr_pck, IPPROTO_HOPOPTS, ext_data2);
+ write_packet(fd, exthdr_pck, total_hdr_len + PAYLOAD_LEN + MIN_EXTHDR_SIZE, daddr);
+}
+
/* IPv4 options shouldn't coalesce */
static void send_ip_options(int fd, struct sockaddr_ll *daddr)
{
@@ -697,7 +752,7 @@ static void send_fragment6(int fd, struct sockaddr_ll *daddr)
create_packet(buf, PAYLOAD_LEN * i, 0, PAYLOAD_LEN, 0);
write_packet(fd, buf, bufpkt_len, daddr);
}
-
+ sleep(1);
create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0);
memset(extpkt, 0, extpkt_len);
@@ -760,6 +815,7 @@ static void check_recv_pkts(int fd, int *correct_payload,
vlog("}, Total %d packets\nReceived {", correct_num_pkts);
while (1) {
+ ip_ext_len = 0;
pkt_size = recv(fd, buffer, IP_MAXPACKET + ETH_HLEN + 1, 0);
if (pkt_size < 0)
error(1, errno, "could not receive");
@@ -767,7 +823,7 @@ static void check_recv_pkts(int fd, int *correct_payload,
if (iph->version == 4)
ip_ext_len = (iph->ihl - 5) * 4;
else if (ip6h->version == 6 && ip6h->nexthdr != IPPROTO_TCP)
- ip_ext_len = sizeof(struct ip6_frag);
+ ip_ext_len = MIN_EXTHDR_SIZE;
tcph = (struct tcphdr *)(buffer + tcp_offset + ip_ext_len);
@@ -880,7 +936,21 @@ static void gro_sender(void)
sleep(1);
write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
} else if (proto == PF_INET6) {
+ sleep(1);
send_fragment6(txfd, &daddr);
+ sleep(1);
+ write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
+
+ sleep(1);
+ /* send IPv6 packets with ext header with same payload */
+ send_ipv6_exthdr(txfd, &daddr, EXT_PAYLOAD_1, EXT_PAYLOAD_1);
+ sleep(1);
+ write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
+
+ sleep(1);
+ /* send IPv6 packets with ext header with different payload */
+ send_ipv6_exthdr(txfd, &daddr, EXT_PAYLOAD_1, EXT_PAYLOAD_2);
+ sleep(1);
write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
}
} else if (strcmp(testname, "large") == 0) {
@@ -997,6 +1067,17 @@ static void gro_receiver(void)
*/
printf("fragmented ip6 doesn't coalesce: ");
correct_payload[0] = PAYLOAD_LEN * 2;
+ correct_payload[1] = PAYLOAD_LEN;
+ correct_payload[2] = PAYLOAD_LEN;
+ check_recv_pkts(rxfd, correct_payload, 3);
+
+ printf("ipv6 with ext header does coalesce: ");
+ correct_payload[0] = PAYLOAD_LEN * 2;
+ check_recv_pkts(rxfd, correct_payload, 1);
+
+ printf("ipv6 with ext header with different payloads doesn't coalesce: ");
+ correct_payload[0] = PAYLOAD_LEN;
+ correct_payload[1] = PAYLOAD_LEN;
check_recv_pkts(rxfd, correct_payload, 2);
}
} else if (strcmp(testname, "large") == 0) {
--
2.36.1
^ permalink raw reply related [flat|nested] 6+ messages in thread