This series fixes a bug in the complete phase of UDP in GRO, in which socket lookup fails due to using network_header when parsing encapsulated packets. The fix is to pass p_off parameter in *_gro_complete.
Next, the fields network_offset and inner_network_offset are added to napi_gro_cb, and are both set during the receive phase of GRO. This is then leveraged in the next commit to remove flush_id state from napi_gro_cb, and stateful code in {ipv6,inet}_gro_receive which may be unnecessarily complicated due to encapsulation support in GRO.
In addition, udpgro_fwd selftest is adjusted to include the socket lookup case for vxlan. This selftest will test its supposed functionality once local bind support is merged (https://lore.kernel.org/netdev/df300a49-7811-4126-a56a-a77100c8841b@gmail.co...).
v2 -> v3: - Use napi_gro_cb instead of skb->{offset} - v2: https://lore.kernel.org/netdev/2ce1600b-e733-448b-91ac-9d0ae2b866a4@gmail.co...
v1 -> v2: - Pass p_off in *_gro_complete to fix UDP bug - Remove more conditionals and memory fetches from inet_gro_flush - v1: https://lore.kernel.org/netdev/e1d22505-c5f8-4c02-a997-64248480338b@gmail.co...
Richard Gobert (4): net: gro: add p_off param in *_gro_complete selftests/net: add local address bind in vxlan selftest net: gro: add {inner_}network_offset to napi_gro_cb net: gro: move L3 flush checks to tcp_gro_receive
drivers/net/geneve.c | 7 +- drivers/net/vxlan/vxlan_core.c | 11 ++-- include/linux/etherdevice.h | 2 +- include/linux/netdevice.h | 3 +- include/linux/udp.h | 2 +- include/net/gro.h | 36 +++++++---- include/net/inet_common.h | 2 +- include/net/tcp.h | 6 +- include/net/udp.h | 8 +-- include/net/udp_tunnel.h | 2 +- net/8021q/vlan_core.c | 6 +- net/core/gro.c | 6 +- net/ethernet/eth.c | 5 +- net/ipv4/af_inet.c | 49 ++------------ net/ipv4/fou_core.c | 9 +-- net/ipv4/gre_offload.c | 6 +- net/ipv4/tcp_offload.c | 79 ++++++++++++++++++----- net/ipv4/udp.c | 3 +- net/ipv4/udp_offload.c | 26 ++++---- net/ipv6/ip6_offload.c | 41 +++++------- net/ipv6/tcpv6_offload.c | 7 +- net/ipv6/udp.c | 3 +- net/ipv6/udp_offload.c | 13 ++-- tools/testing/selftests/net/udpgro_fwd.sh | 10 ++- 24 files changed, 187 insertions(+), 155 deletions(-)
Commits a602456 ("udp: Add GRO functions to UDP socket") and 57c67ff ("udp: additional GRO support") introduce incorrect usage of {ip,ipv6}_hdr in the complete phase of gro. The functions always return skb->network_header, which in the case of encapsulated packets at the gro complete phase, is always set to the innermost L3 of the packet. That means that calling {ip,ipv6}_hdr for skbs which completed the GRO receive phase (both in gro_list and *_gro_complete) when parsing an encapsulated packet's _outer_ L3/L4 may return an unexpected value.
This incorrect usage leads to a bug in GRO's UDP socket lookup. udp{4,6}_lib_lookup_skb functions use ip_hdr/ipv6_hdr respectively. These *_hdr functions return network_header which will point to the innermost L3, resulting in the wrong offset being used in __udp{4,6}_lib_lookup with encapsulated packets.
To fix this issue p_off param is used in *_gro_complete to pass off the offset of the previous layer.
Reproduction example:
Endpoint configuration example (fou + local address bind)
# ip fou add port 6666 ipproto 4 # ip link add name tun1 type ipip remote 2.2.2.1 local 2.2.2.2 encap fou encap-dport 5555 encap-sport 6666 mode ipip # ip link set tun1 up # ip a add 1.1.1.2/24 dev tun1
Netperf TCP_STREAM result on net-next before patch is applied:
net-next main, GRO enabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec
131072 16384 16384 5.28 2.37
net-next main, GRO disabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec
131072 16384 16384 5.01 2745.06
patch applied, GRO enabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec
131072 16384 16384 5.01 2877.38
Fixes: 57c67ff4bd92 ("udp: additional GRO support") Suggested-by: Eric Dumazet edumazet@google.com Signed-off-by: Richard Gobert richardbgobert@gmail.com --- drivers/net/geneve.c | 7 ++++--- drivers/net/vxlan/vxlan_core.c | 11 +++++++---- include/linux/etherdevice.h | 2 +- include/linux/netdevice.h | 3 ++- include/linux/udp.h | 2 +- include/net/gro.h | 11 ++++++----- include/net/inet_common.h | 2 +- include/net/tcp.h | 6 ++++-- include/net/udp.h | 8 ++++---- include/net/udp_tunnel.h | 2 +- net/8021q/vlan_core.c | 4 ++-- net/core/gro.c | 2 +- net/ethernet/eth.c | 4 ++-- net/ipv4/af_inet.c | 8 ++++---- net/ipv4/fou_core.c | 9 +++++---- net/ipv4/gre_offload.c | 5 +++-- net/ipv4/tcp_offload.c | 7 ++++--- net/ipv4/udp.c | 3 ++- net/ipv4/udp_offload.c | 26 ++++++++++++++------------ net/ipv6/ip6_offload.c | 22 ++++++++++++---------- net/ipv6/tcpv6_offload.c | 7 ++++--- net/ipv6/udp.c | 3 ++- net/ipv6/udp_offload.c | 13 +++++++------ 23 files changed, 93 insertions(+), 74 deletions(-)
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index e25e0a31126c..75837b3fb2d3 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -546,7 +546,7 @@ static struct sk_buff *geneve_gro_receive(struct sock *sk, }
static int geneve_gro_complete(struct sock *sk, struct sk_buff *skb, - int nhoff) + int p_off, int nhoff) { struct genevehdr *gh; struct packet_offload *ptype; @@ -560,11 +560,12 @@ static int geneve_gro_complete(struct sock *sk, struct sk_buff *skb,
/* since skb->encapsulation is set, eth_gro_complete() sets the inner mac header */ if (likely(type == htons(ETH_P_TEB))) - return eth_gro_complete(skb, nhoff + gh_len); + return eth_gro_complete(skb, p_off, nhoff + gh_len);
ptype = gro_find_complete_by_type(type); if (ptype) - err = ptype->callbacks.gro_complete(skb, nhoff + gh_len); + err = ptype->callbacks.gro_complete(skb, p_off, + nhoff + gh_len);
skb_set_inner_mac_header(skb, nhoff + gh_len);
diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c index 386cbe4d3327..84c123405b70 100644 --- a/drivers/net/vxlan/vxlan_core.c +++ b/drivers/net/vxlan/vxlan_core.c @@ -767,15 +767,17 @@ static struct sk_buff *vxlan_gpe_gro_receive(struct sock *sk, return pp; }
-static int vxlan_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) +static int vxlan_gro_complete(struct sock *sk, struct sk_buff *skb, + int p_off, int nhoff) { /* Sets 'skb->inner_mac_header' since we are always called with * 'skb->encapsulation' set. */ - return eth_gro_complete(skb, nhoff + sizeof(struct vxlanhdr)); + return eth_gro_complete(skb, p_off, nhoff + sizeof(struct vxlanhdr)); }
-static int vxlan_gpe_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) +static int vxlan_gpe_gro_complete(struct sock *sk, struct sk_buff *skb, + int p_off, int nhoff) { struct vxlanhdr *vh = (struct vxlanhdr *)(skb->data + nhoff); const struct packet_offload *ptype; @@ -786,7 +788,8 @@ static int vxlan_gpe_gro_complete(struct sock *sk, struct sk_buff *skb, int nhof return err; ptype = gro_find_complete_by_type(protocol); if (ptype) - err = ptype->callbacks.gro_complete(skb, nhoff + sizeof(struct vxlanhdr)); + err = ptype->callbacks.gro_complete(skb, p_off, nhoff + + sizeof(struct vxlanhdr)); return err; }
diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 224645f17c33..b081b43d9686 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -64,7 +64,7 @@ struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv, #define devm_alloc_etherdev(dev, sizeof_priv) devm_alloc_etherdev_mqs(dev, sizeof_priv, 1, 1)
struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb); -int eth_gro_complete(struct sk_buff *skb, int nhoff); +int eth_gro_complete(struct sk_buff *skb, int p_off, int nhoff);
/* Reserved Ethernet Addresses per IEEE 802.1Q */ static const u8 eth_reserved_addr_base[ETH_ALEN] __aligned(2) = diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index c41019f34179..5a7049f83e41 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2788,7 +2788,8 @@ struct offload_callbacks { netdev_features_t features); struct sk_buff *(*gro_receive)(struct list_head *head, struct sk_buff *skb); - int (*gro_complete)(struct sk_buff *skb, int nhoff); + int (*gro_complete)(struct sk_buff *skb, int nhoff, + int thoff); };
struct packet_offload { diff --git a/include/linux/udp.h b/include/linux/udp.h index 3748e82b627b..a04d94a3b42f 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -82,7 +82,7 @@ struct udp_sock { struct sk_buff *skb); int (*gro_complete)(struct sock *sk, struct sk_buff *skb, - int nhoff); + int nhoff, int thoff);
/* udp_recvmsg try to use this before splicing sk_receive_queue */ struct sk_buff_head reader_queue ____cacheline_aligned_in_smp; diff --git a/include/net/gro.h b/include/net/gro.h index 2b58671a6549..cb7282bf3d63 100644 --- a/include/net/gro.h +++ b/include/net/gro.h @@ -382,18 +382,18 @@ static inline void skb_gro_flush_final_remcsum(struct sk_buff *skb,
INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *, struct sk_buff *)); -INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int)); +INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int, int)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *inet_gro_receive(struct list_head *, struct sk_buff *)); -INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int)); +INDIRECT_CALLABLE_DECLARE(int inet_gro_complete(struct sk_buff *, int, int));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *, struct sk_buff *)); -INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int)); +INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int, int));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *, struct sk_buff *)); -INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int)); +INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int, int));
#define indirect_call_gro_receive_inet(cb, f2, f1, head, skb) \ ({ \ @@ -404,7 +404,8 @@ INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb, struct udphdr *uh, struct sock *sk); -int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup); +int udp_gro_complete(struct sk_buff *skb, int nhoff, int thoff, + udp_lookup_t lookup);
static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb) { diff --git a/include/net/inet_common.h b/include/net/inet_common.h index f50a644d87a9..605f917c830c 100644 --- a/include/net/inet_common.h +++ b/include/net/inet_common.h @@ -64,7 +64,7 @@ int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb); -int inet_gro_complete(struct sk_buff *skb, int nhoff); +int inet_gro_complete(struct sk_buff *skb, int nhoff, int thoff); struct sk_buff *inet_gso_segment(struct sk_buff *skb, netdev_features_t features);
diff --git a/include/net/tcp.h b/include/net/tcp.h index 6ae35199d3b3..f36f15b6fb49 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2196,9 +2196,11 @@ void tcp_v4_destroy_sock(struct sock *sk); struct sk_buff *tcp_gso_segment(struct sk_buff *skb, netdev_features_t features); struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb); -INDIRECT_CALLABLE_DECLARE(int tcp4_gro_complete(struct sk_buff *skb, int thoff)); +INDIRECT_CALLABLE_DECLARE(int tcp4_gro_complete(struct sk_buff *skb, int nhoff, + int thoff)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp4_gro_receive(struct list_head *head, struct sk_buff *skb)); -INDIRECT_CALLABLE_DECLARE(int tcp6_gro_complete(struct sk_buff *skb, int thoff)); +INDIRECT_CALLABLE_DECLARE(int tcp6_gro_complete(struct sk_buff *skb, int nhoff, + int thoff)); INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp6_gro_receive(struct list_head *head, struct sk_buff *skb)); #ifdef CONFIG_INET void tcp_gro_complete(struct sk_buff *skb); diff --git a/include/net/udp.h b/include/net/udp.h index 488a6d2babcc..601d1c3b677a 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -166,8 +166,8 @@ static inline void udp_csum_pull_header(struct sk_buff *skb) UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr); }
-typedef struct sock *(*udp_lookup_t)(const struct sk_buff *skb, __be16 sport, - __be16 dport); +typedef struct sock *(*udp_lookup_t)(const struct sk_buff *skb, int nhoff, + __be16 sport, __be16 dport);
void udp_v6_early_demux(struct sk_buff *skb); INDIRECT_CALLABLE_DECLARE(int udpv6_rcv(struct sk_buff *)); @@ -301,7 +301,7 @@ struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, __be32 daddr, __be16 dport, int dif, int sdif, struct udp_table *tbl, struct sk_buff *skb); -struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb, +struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb, int nhoff, __be16 sport, __be16 dport); struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, @@ -312,7 +312,7 @@ struct sock *__udp6_lib_lookup(struct net *net, const struct in6_addr *daddr, __be16 dport, int dif, int sdif, struct udp_table *tbl, struct sk_buff *skb); -struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, +struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, int nhoff, __be16 sport, __be16 dport); int udp_read_skb(struct sock *sk, skb_read_actor_t recv_actor);
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h index d716214fe03d..a641392e70b0 100644 --- a/include/net/udp_tunnel.h +++ b/include/net/udp_tunnel.h @@ -75,7 +75,7 @@ typedef struct sk_buff *(*udp_tunnel_gro_receive_t)(struct sock *sk, struct list_head *head, struct sk_buff *skb); typedef int (*udp_tunnel_gro_complete_t)(struct sock *sk, struct sk_buff *skb, - int nhoff); + int nhoff, int thoff);
struct udp_tunnel_sock_cfg { void *sk_user_data; /* user data used by encap_rcv call back */ diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c index f00158234505..247704cf70af 100644 --- a/net/8021q/vlan_core.c +++ b/net/8021q/vlan_core.c @@ -510,7 +510,7 @@ static struct sk_buff *vlan_gro_receive(struct list_head *head, return pp; }
-static int vlan_gro_complete(struct sk_buff *skb, int nhoff) +static int vlan_gro_complete(struct sk_buff *skb, int p_off, int nhoff) { struct vlan_hdr *vhdr = (struct vlan_hdr *)(skb->data + nhoff); __be16 type = vhdr->h_vlan_encapsulated_proto; @@ -521,7 +521,7 @@ static int vlan_gro_complete(struct sk_buff *skb, int nhoff) if (ptype) err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete, ipv6_gro_complete, inet_gro_complete, - skb, nhoff + sizeof(*vhdr)); + skb, p_off, nhoff + sizeof(*vhdr));
return err; } diff --git a/net/core/gro.c b/net/core/gro.c index 6a0edbd826a1..7da3df2c634f 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -254,7 +254,7 @@ static void napi_gro_complete(struct napi_struct *napi, struct sk_buff *skb)
err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete, ipv6_gro_complete, inet_gro_complete, - skb, 0); + skb, 0, 0); break; } rcu_read_unlock(); diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 2edc8b796a4e..7515e6bcbb7d 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -453,7 +453,7 @@ struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb) } EXPORT_SYMBOL(eth_gro_receive);
-int eth_gro_complete(struct sk_buff *skb, int nhoff) +int eth_gro_complete(struct sk_buff *skb, int p_off, int nhoff) { struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff); __be16 type = eh->h_proto; @@ -467,7 +467,7 @@ int eth_gro_complete(struct sk_buff *skb, int nhoff) if (ptype != NULL) err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete, ipv6_gro_complete, inet_gro_complete, - skb, nhoff + sizeof(*eh)); + skb, p_off, nhoff + sizeof(*eh));
return err; } diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 5daebdcbca32..9334b563a88b 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1640,7 +1640,7 @@ int inet_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) } EXPORT_SYMBOL(inet_recv_error);
-int inet_gro_complete(struct sk_buff *skb, int nhoff) +int inet_gro_complete(struct sk_buff *skb, int prior_off, int nhoff) { struct iphdr *iph = (struct iphdr *)(skb->data + nhoff); const struct net_offload *ops; @@ -1666,17 +1666,17 @@ int inet_gro_complete(struct sk_buff *skb, int nhoff) */ err = INDIRECT_CALL_2(ops->callbacks.gro_complete, tcp4_gro_complete, udp4_gro_complete, - skb, nhoff + sizeof(*iph)); + skb, nhoff, nhoff + sizeof(*iph));
out: return err; }
-static int ipip_gro_complete(struct sk_buff *skb, int nhoff) +static int ipip_gro_complete(struct sk_buff *skb, int prior_off, int nhoff) { skb->encapsulation = 1; skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4; - return inet_gro_complete(skb, nhoff); + return inet_gro_complete(skb, prior_off, nhoff); }
int inet_ctl_sock_create(struct sock **sk, unsigned short family, diff --git a/net/ipv4/fou_core.c b/net/ipv4/fou_core.c index a8494f796dca..7cf214d0b96d 100644 --- a/net/ipv4/fou_core.c +++ b/net/ipv4/fou_core.c @@ -260,7 +260,7 @@ static struct sk_buff *fou_gro_receive(struct sock *sk, }
static int fou_gro_complete(struct sock *sk, struct sk_buff *skb, - int nhoff) + int p_off, int nhoff) { const struct net_offload __rcu **offloads; u8 proto = fou_from_sock(sk)->protocol; @@ -272,7 +272,7 @@ static int fou_gro_complete(struct sock *sk, struct sk_buff *skb, if (WARN_ON(!ops || !ops->callbacks.gro_complete)) goto out;
- err = ops->callbacks.gro_complete(skb, nhoff); + err = ops->callbacks.gro_complete(skb, p_off, nhoff);
skb_set_inner_mac_header(skb, nhoff);
@@ -445,7 +445,8 @@ static struct sk_buff *gue_gro_receive(struct sock *sk, return pp; }
-static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) +static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, + int p_off, int nhoff) { struct guehdr *guehdr = (struct guehdr *)(skb->data + nhoff); const struct net_offload __rcu **offloads; @@ -480,7 +481,7 @@ static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) if (WARN_ON(!ops || !ops->callbacks.gro_complete)) goto out;
- err = ops->callbacks.gro_complete(skb, nhoff + guehlen); + err = ops->callbacks.gro_complete(skb, p_off, nhoff + guehlen);
skb_set_inner_mac_header(skb, nhoff + guehlen);
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c index 5028c72d494a..d4520c3f7c09 100644 --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -233,7 +233,7 @@ static struct sk_buff *gre_gro_receive(struct list_head *head, return pp; }
-static int gre_gro_complete(struct sk_buff *skb, int nhoff) +static int gre_gro_complete(struct sk_buff *skb, int p_off, int nhoff) { struct gre_base_hdr *greh = (struct gre_base_hdr *)(skb->data + nhoff); struct packet_offload *ptype; @@ -253,7 +253,8 @@ static int gre_gro_complete(struct sk_buff *skb, int nhoff)
ptype = gro_find_complete_by_type(type); if (ptype) - err = ptype->callbacks.gro_complete(skb, nhoff + grehlen); + err = ptype->callbacks.gro_complete(skb, p_off, + nhoff + grehlen);
skb_set_inner_mac_header(skb, nhoff + grehlen);
diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index b955ab3b236d..fde800179b2e 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -330,10 +330,11 @@ struct sk_buff *tcp4_gro_receive(struct list_head *head, struct sk_buff *skb) return tcp_gro_receive(head, skb); }
-INDIRECT_CALLABLE_SCOPE int tcp4_gro_complete(struct sk_buff *skb, int thoff) +INDIRECT_CALLABLE_SCOPE int tcp4_gro_complete(struct sk_buff *skb, int nhoff, + int thoff) { - const struct iphdr *iph = ip_hdr(skb); - struct tcphdr *th = tcp_hdr(skb); + const struct iphdr *iph = (const struct iphdr *)(skb->data + nhoff); + struct tcphdr *th = (struct tcphdr *)(skb->data + thoff);
th->check = ~tcp_v4_check(skb->len - thoff, iph->saddr, iph->daddr, 0); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index a8acea17b4e5..70a6d174855f 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -532,9 +532,10 @@ static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb, }
struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb, + int nhoff, __be16 sport, __be16 dport) { - const struct iphdr *iph = ip_hdr(skb); + const struct iphdr *iph = (const struct iphdr *)(skb->data + nhoff); struct net *net = dev_net(skb->dev); int iif, sdif;
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 6c95d28d0c4a..cba615d52300 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -669,18 +669,19 @@ static int udp_gro_complete_segment(struct sk_buff *skb) return 0; }
-int udp_gro_complete(struct sk_buff *skb, int nhoff, +int udp_gro_complete(struct sk_buff *skb, int nhoff, int thoff, udp_lookup_t lookup) { - __be16 newlen = htons(skb->len - nhoff); - struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); + struct udphdr *uh = (struct udphdr *)(skb->data + thoff); + __be16 newlen = htons(skb->len - thoff); struct sock *sk; int err;
uh->len = newlen;
sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb, - udp4_lib_lookup_skb, skb, uh->source, uh->dest); + udp4_lib_lookup_skb, skb, nhoff, uh->source, + uh->dest); if (sk && udp_sk(sk)->gro_complete) { skb_shinfo(skb)->gso_type = uh->check ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL; @@ -694,8 +695,8 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff, * functions to make them set up the inner offsets. */ skb->encapsulation = 1; - err = udp_sk(sk)->gro_complete(sk, skb, - nhoff + sizeof(struct udphdr)); + err = udp_sk(sk)->gro_complete(sk, skb, nhoff, + thoff + sizeof(struct udphdr)); } else { err = udp_gro_complete_segment(skb); } @@ -707,14 +708,15 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff, } EXPORT_SYMBOL(udp_gro_complete);
-INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff) +INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff, + int thoff) { - const struct iphdr *iph = ip_hdr(skb); - struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); + const struct iphdr *iph = (const struct iphdr *)(skb->data + nhoff); + struct udphdr *uh = (struct udphdr *)(skb->data + thoff);
/* do fraglist only if there is no outer UDP encap (or we already processed it) */ if (NAPI_GRO_CB(skb)->is_flist && !NAPI_GRO_CB(skb)->encap_mark) { - uh->len = htons(skb->len - nhoff); + uh->len = htons(skb->len - thoff);
skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4); skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; @@ -731,10 +733,10 @@ INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff) }
if (uh->check) - uh->check = ~udp_v4_check(skb->len - nhoff, iph->saddr, + uh->check = ~udp_v4_check(skb->len - thoff, iph->saddr, iph->daddr, 0);
- return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb); + return udp_gro_complete(skb, nhoff, thoff, udp4_lib_lookup_skb); }
static const struct net_offload udpv4_offload = { diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index cca64c7809be..e3a05b84c76a 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -346,12 +346,14 @@ static struct sk_buff *ip4ip6_gro_receive(struct list_head *head, return inet_gro_receive(head, skb); }
-INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff) +INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, + int p_off, int nhoff) { const struct net_offload *ops; struct ipv6hdr *iph; int err = -ENOSYS; u32 payload_len; + int nhlen;
if (skb->encapsulation) { skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IPV6)); @@ -387,36 +389,36 @@ INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff) iph->payload_len = htons(payload_len); }
- nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); - if (WARN_ON(!ops || !ops->callbacks.gro_complete)) + nhlen = sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); + if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_complete)) goto out;
err = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete, - udp6_gro_complete, skb, nhoff); + udp6_gro_complete, skb, nhoff, nhoff + nhlen);
out: return err; }
-static int sit_gro_complete(struct sk_buff *skb, int nhoff) +static int sit_gro_complete(struct sk_buff *skb, int p_off, int nhoff) { skb->encapsulation = 1; skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4; - return ipv6_gro_complete(skb, nhoff); + return ipv6_gro_complete(skb, p_off, nhoff); }
-static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff) +static int ip6ip6_gro_complete(struct sk_buff *skb, int p_off, int nhoff) { skb->encapsulation = 1; skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6; - return ipv6_gro_complete(skb, nhoff); + return ipv6_gro_complete(skb, p_off, nhoff); }
-static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff) +static int ip4ip6_gro_complete(struct sk_buff *skb, int p_off, int nhoff) { skb->encapsulation = 1; skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6; - return inet_gro_complete(skb, nhoff); + return inet_gro_complete(skb, p_off, nhoff); }
static struct packet_offload ipv6_packet_offload __read_mostly = { diff --git a/net/ipv6/tcpv6_offload.c b/net/ipv6/tcpv6_offload.c index bf0c957e4b5e..5043d2ff34eb 100644 --- a/net/ipv6/tcpv6_offload.c +++ b/net/ipv6/tcpv6_offload.c @@ -27,10 +27,11 @@ struct sk_buff *tcp6_gro_receive(struct list_head *head, struct sk_buff *skb) return tcp_gro_receive(head, skb); }
-INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff) +INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, + int nhoff, int thoff) { - const struct ipv6hdr *iph = ipv6_hdr(skb); - struct tcphdr *th = tcp_hdr(skb); + const struct ipv6hdr *iph = (const struct ipv6hdr *)(skb->data + nhoff); + struct tcphdr *th = (struct tcphdr *)(skb->data + thoff);
th->check = ~tcp_v6_check(skb->len - thoff, &iph->saddr, &iph->daddr, 0); diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 3f2249b4cd5f..400243c89d82 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -273,9 +273,10 @@ static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, }
struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, + int nhoff, __be16 sport, __be16 dport) { - const struct ipv6hdr *iph = ipv6_hdr(skb); + const struct ipv6hdr *iph = (const struct ipv6hdr *)(skb->data + nhoff); struct net *net = dev_net(skb->dev); int iif, sdif;
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index 6b95ba241ebe..f930efd27180 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -162,14 +162,15 @@ struct sk_buff *udp6_gro_receive(struct list_head *head, struct sk_buff *skb) return NULL; }
-INDIRECT_CALLABLE_SCOPE int udp6_gro_complete(struct sk_buff *skb, int nhoff) +INDIRECT_CALLABLE_SCOPE int udp6_gro_complete(struct sk_buff *skb, int nhoff, + int thoff) { - const struct ipv6hdr *ipv6h = ipv6_hdr(skb); - struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); + const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)(skb->data + nhoff); + struct udphdr *uh = (struct udphdr *)(skb->data + thoff);
/* do fraglist only if there is no outer UDP encap (or we already processed it) */ if (NAPI_GRO_CB(skb)->is_flist && !NAPI_GRO_CB(skb)->encap_mark) { - uh->len = htons(skb->len - nhoff); + uh->len = htons(skb->len - thoff);
skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4); skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count; @@ -186,10 +187,10 @@ INDIRECT_CALLABLE_SCOPE int udp6_gro_complete(struct sk_buff *skb, int nhoff) }
if (uh->check) - uh->check = ~udp_v6_check(skb->len - nhoff, &ipv6h->saddr, + uh->check = ~udp_v6_check(skb->len - thoff, &ipv6h->saddr, &ipv6h->daddr, 0);
- return udp_gro_complete(skb, nhoff, udp6_lib_lookup_skb); + return udp_gro_complete(skb, nhoff, thoff, udp6_lib_lookup_skb); }
static const struct net_offload udpv6_offload = {
Add local address bind support to existing udpgro_fwd.sh vxlan selftest, to ensure UDP socket lookup in GRO is working.
Signed-off-by: Richard Gobert richardbgobert@gmail.com --- tools/testing/selftests/net/udpgro_fwd.sh | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/net/udpgro_fwd.sh b/tools/testing/selftests/net/udpgro_fwd.sh index 9cd5e885e91f..ed66365a2fc5 100755 --- a/tools/testing/selftests/net/udpgro_fwd.sh +++ b/tools/testing/selftests/net/udpgro_fwd.sh @@ -62,11 +62,13 @@ create_vxlan_endpoint() { local -r bm_rem_addr=$3 local -r vxlan_dev=$4 local -r vxlan_id=$5 + local -r bm_local_addr=$6 local -r vxlan_port=4789
ip -n $netns link set dev $bm_dev up ip -n $netns link add dev $vxlan_dev type vxlan id $vxlan_id \ - dstport $vxlan_port remote $bm_rem_addr + dstport $vxlan_port local $bm_local_addr \ + remote $bm_rem_addr ip -n $netns link set dev $vxlan_dev up }
@@ -77,11 +79,13 @@ create_vxlan_pair() {
for ns in $SRC $DST; do # note that 3 - $SRC == $DST and 3 - $DST == $SRC - create_vxlan_endpoint $BASE$ns veth$ns $BM_NET_V4$((3 - $ns)) vxlan$ns 4 + create_vxlan_endpoint $BASE$ns veth$ns $BM_NET_V4$((3 - $ns)) \ + vxlan$ns 4 $BM_NET_V4$ns ip -n $BASE$ns addr add dev vxlan$ns $OL_NET_V4$ns/24 done for ns in $SRC $DST; do - create_vxlan_endpoint $BASE$ns veth$ns $BM_NET_V6$((3 - $ns)) vxlan6$ns 6 + create_vxlan_endpoint $BASE$ns veth$ns $BM_NET_V6$((3 - $ns)) \ + vxlan6$ns 6 $BM_NET_V6$ns ip -n $BASE$ns addr add dev vxlan6$ns $OL_NET_V6$ns/24 nodad done
This patch adds network_offset and inner_network_offset to napi_gro_cb, and makes sure both are set correctly. In the common path there's only one write (skb_gro_reset_offset).
Signed-off-by: Richard Gobert richardbgobert@gmail.com --- include/net/gro.h | 18 ++++++++++++++++-- net/8021q/vlan_core.c | 2 ++ net/core/gro.c | 1 + net/ethernet/eth.c | 1 + net/ipv4/af_inet.c | 5 +---- net/ipv4/gre_offload.c | 1 + net/ipv6/ip6_offload.c | 8 ++++---- 7 files changed, 26 insertions(+), 10 deletions(-)
diff --git a/include/net/gro.h b/include/net/gro.h index cb7282bf3d63..9d1389269509 100644 --- a/include/net/gro.h +++ b/include/net/gro.h @@ -86,6 +86,15 @@ struct napi_gro_cb {
/* used to support CHECKSUM_COMPLETE for tunneling protocols */ __wsum csum; + + /* L3 offsets */ + union { + struct { + u16 network_offset; + u16 inner_network_offset; + }; + u16 network_offsets[2]; + }; };
#define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb) @@ -171,12 +180,17 @@ static inline void *skb_gro_header(struct sk_buff *skb, unsigned int hlen, return ptr; }
+static inline int skb_gro_network_offset(const struct sk_buff *skb) +{ + return NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark]; +} + static inline void *skb_gro_network_header(const struct sk_buff *skb) { if (skb_gro_may_pull(skb, skb_gro_offset(skb))) - return skb_gro_header_fast(skb, skb_network_offset(skb)); + return skb_gro_header_fast(skb, skb_gro_network_offset(skb));
- return skb_network_header(skb); + return skb->data + skb_gro_network_offset(skb); }
static inline __wsum inet_gro_compute_pseudo(const struct sk_buff *skb, diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c index 247704cf70af..355cafe23329 100644 --- a/net/8021q/vlan_core.c +++ b/net/8021q/vlan_core.c @@ -478,6 +478,8 @@ static struct sk_buff *vlan_gro_receive(struct list_head *head, if (unlikely(!vhdr)) goto out;
+ NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark] = hlen; + type = vhdr->h_vlan_encapsulated_proto;
ptype = gro_find_receive_by_type(type); diff --git a/net/core/gro.c b/net/core/gro.c index 7da3df2c634f..2b42138f816c 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -373,6 +373,7 @@ static inline void skb_gro_reset_offset(struct sk_buff *skb, u32 nhoff) const skb_frag_t *frag0; unsigned int headlen;
+ NAPI_GRO_CB(skb)->network_offset = 0; NAPI_GRO_CB(skb)->data_offset = 0; headlen = skb_headlen(skb); NAPI_GRO_CB(skb)->frag0 = skb->data; diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 7515e6bcbb7d..e3eca605bcc7 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -441,6 +441,7 @@ struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
skb_gro_pull(skb, sizeof(*eh)); skb_gro_postpull_rcsum(skb, eh, sizeof(*eh)); + NAPI_GRO_CB(skb)->inner_network_offset = hlen;
pp = indirect_call_gro_receive_inet(ptype->callbacks.gro_receive, ipv6_gro_receive, inet_gro_receive, diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 9334b563a88b..c6bb21c27aee 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1567,10 +1567,6 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF)); NAPI_GRO_CB(skb)->flush |= flush; - skb_set_network_header(skb, off); - /* The above will be needed by the transport layer if there is one - * immediately following this IP hdr. - */
/* Note : No need to call skb_gro_postpull_rcsum() here, * as we already checked checksum over ipv4 header was 0 @@ -1596,6 +1592,7 @@ static struct sk_buff *ipip_gro_receive(struct list_head *head, }
NAPI_GRO_CB(skb)->encap_mark = 1; + NAPI_GRO_CB(skb)->inner_network_offset = skb_gro_offset(skb);
return inet_gro_receive(head, skb); } diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c index d4520c3f7c09..ae596285d78c 100644 --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -224,6 +224,7 @@ static struct sk_buff *gre_gro_receive(struct list_head *head, /* Adjusted NAPI_GRO_CB(skb)->csum after skb_gro_pull()*/ skb_gro_postpull_rcsum(skb, greh, grehlen);
+ NAPI_GRO_CB(skb)->inner_network_offset = hlen; pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb); flush = 0;
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index e3a05b84c76a..d9d3a6bed510 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -67,7 +67,7 @@ static int ipv6_gro_pull_exthdrs(struct sk_buff *skb, int off, int proto) off += len; }
- skb_gro_pull(skb, off - skb_network_offset(skb)); + skb_gro_pull(skb, off - skb_gro_network_offset(skb)); return proto; }
@@ -236,8 +236,6 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head, if (unlikely(!iph)) goto out;
- skb_set_network_header(skb, off); - flush += ntohs(iph->payload_len) != skb->len - hlen;
proto = iph->nexthdr; @@ -259,7 +257,7 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head, NAPI_GRO_CB(skb)->proto = proto;
flush--; - nlen = skb_network_header_len(skb); + nlen = skb_gro_offset(skb) - off;
list_for_each_entry(p, head, list) { const struct ipv6hdr *iph2; @@ -327,6 +325,7 @@ static struct sk_buff *sit_ip6ip6_gro_receive(struct list_head *head, }
NAPI_GRO_CB(skb)->encap_mark = 1; + NAPI_GRO_CB(skb)->inner_network_offset = skb_gro_offset(skb);
return ipv6_gro_receive(head, skb); } @@ -342,6 +341,7 @@ static struct sk_buff *ip4ip6_gro_receive(struct list_head *head, }
NAPI_GRO_CB(skb)->encap_mark = 1; + NAPI_GRO_CB(skb)->inner_network_offset = skb_gro_offset(skb);
return inet_gro_receive(head, skb); }
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets. Furthermore, they need to be done only once in tcp_gro_receive and only against the found p skb, since they only affect flush and not same_flow.
Levaraging the previous commit in the series, in which correct network header offsets are saved for both outer and inner network headers - allowing these checks to be done only once, in tcp_gro_receive. As a result, NAPI_GRO_CB(p)->flush is not used at all. In addition - flush_id checks are more declerative and contained in inet_gro_flush, thus removing the need for flush_id in napi_gro_cb.
This results in less parsing code for UDP flows and non-loop flush tests for TCP flows.
For example, running 40 IP/UDP netperf connections: ./super_netperf.sh 40 -H 1.1.1.2 -t UDP_STREAM -l 120
Running perf top for 90s we can see that relatively less time is spent on inet_gro_receive when GRO is not coalescing UDP:
net-next: 1.26% [kernel] [k] inet_gro_receive
patch applied: 0.85% [kernel] [k] inet_gro_receive
udpgro_bench.sh single connection GRO improvement: net-next: 0.76% [kernel] [k] inet_gro_receive
patch applied: 0.61% [kernel] [k] inet_gro_receive
Signed-off-by: Richard Gobert richardbgobert@gmail.com --- include/net/gro.h | 9 ++---- net/core/gro.c | 3 -- net/ipv4/af_inet.c | 36 --------------------- net/ipv4/tcp_offload.c | 72 ++++++++++++++++++++++++++++++++++-------- net/ipv6/ip6_offload.c | 11 ------- 5 files changed, 62 insertions(+), 69 deletions(-)
diff --git a/include/net/gro.h b/include/net/gro.h index 9d1389269509..34e50f77f744 100644 --- a/include/net/gro.h +++ b/include/net/gro.h @@ -35,15 +35,15 @@ struct napi_gro_cb { /* This is non-zero if the packet cannot be merged with the new skb. */ u16 flush;
- /* Save the IP ID here and check when we get to the transport layer */ - u16 flush_id; - /* Number of segments aggregated. */ u16 count;
/* Used in ipv6_gro_receive() and foo-over-udp and esp-in-udp */ u16 proto;
+ /* used to support CHECKSUM_COMPLETE for tunneling protocols */ + __wsum csum; + /* Used in napi_gro_cb::free */ #define NAPI_GRO_FREE 1 #define NAPI_GRO_FREE_STOLEN_HEAD 2 @@ -84,9 +84,6 @@ struct napi_gro_cb { u8 is_flist:1; );
- /* used to support CHECKSUM_COMPLETE for tunneling protocols */ - __wsum csum; - /* L3 offsets */ union { struct { diff --git a/net/core/gro.c b/net/core/gro.c index 2b42138f816c..128d7b9c8dfb 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -332,8 +332,6 @@ static void gro_list_prepare(const struct list_head *head, list_for_each_entry(p, head, list) { unsigned long diffs;
- NAPI_GRO_CB(p)->flush = 0; - if (hash != skb_get_hash_raw(p)) { NAPI_GRO_CB(p)->same_flow = 0; continue; @@ -473,7 +471,6 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff sizeof(u32))); /* Avoid slow unaligned acc */ *(u32 *)&NAPI_GRO_CB(skb)->zeroed = 0; NAPI_GRO_CB(skb)->flush = skb_has_frag_list(skb); - NAPI_GRO_CB(skb)->is_atomic = 1; NAPI_GRO_CB(skb)->count = 1; if (unlikely(skb_is_gso(skb))) { NAPI_GRO_CB(skb)->count = skb_shinfo(skb)->gso_segs; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index c6bb21c27aee..5b74c6d2ed8b 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1512,7 +1512,6 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
list_for_each_entry(p, head, list) { struct iphdr *iph2; - u16 flush_id;
if (!NAPI_GRO_CB(p)->same_flow) continue; @@ -1529,43 +1528,8 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb) NAPI_GRO_CB(p)->same_flow = 0; continue; } - - /* All fields must match except length and checksum. */ - NAPI_GRO_CB(p)->flush |= - (iph->ttl ^ iph2->ttl) | - (iph->tos ^ iph2->tos) | - ((iph->frag_off ^ iph2->frag_off) & htons(IP_DF)); - - NAPI_GRO_CB(p)->flush |= flush; - - /* We need to store of the IP ID check to be included later - * when we can verify that this packet does in fact belong - * to a given flow. - */ - flush_id = (u16)(id - ntohs(iph2->id)); - - /* This bit of code makes it much easier for us to identify - * the cases where we are doing atomic vs non-atomic IP ID - * checks. Specifically an atomic check can return IP ID - * values 0 - 0xFFFF, while a non-atomic check can only - * return 0 or 0xFFFF. - */ - if (!NAPI_GRO_CB(p)->is_atomic || - !(iph->frag_off & htons(IP_DF))) { - flush_id ^= NAPI_GRO_CB(p)->count; - flush_id = flush_id ? 0xFFFF : 0; - } - - /* If the previous IP ID value was based on an atomic - * datagram we can overwrite the value and ignore it. - */ - if (NAPI_GRO_CB(skb)->is_atomic) - NAPI_GRO_CB(p)->flush_id = flush_id; - else - NAPI_GRO_CB(p)->flush_id |= flush_id; }
- NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF)); NAPI_GRO_CB(skb)->flush |= flush;
/* Note : No need to call skb_gro_postpull_rcsum() here, diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index fde800179b2e..c165e72555e1 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -178,6 +178,55 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb, return segs; }
+static int inet_gro_flush(const struct iphdr *iph, const struct iphdr *iph2, + struct sk_buff *p, u32 outer) +{ + const u32 id = ntohl(*(__be32 *)&iph->id); + const u32 id2 = ntohl(*(__be32 *)&iph2->id); + const int flush_id = ntohs(id >> 16) - ntohs(id2 >> 16); + const u16 count = NAPI_GRO_CB(p)->count; + const u32 df = id & IP_DF; + u32 is_atomic; + int flush; + + /* All fields must match except length and checksum. */ + flush = (iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | (df ^ (id2 & IP_DF)); + + /* When we receive our second frame we can make a decision on if we + * continue this flow as an atomic flow with a fixed ID or if we use + * an incremdfenting ID. + */ + if (count == 1) { + is_atomic = df && flush_id == 0; + NAPI_GRO_CB(p)->is_atomic = is_atomic; + } else { + is_atomic = df && NAPI_GRO_CB(p)->is_atomic; + } + + /* Ignore outer IP ID value if based on atomic datagram. */ + outer = (outer && df) - 1; + is_atomic--; + + return flush | ((flush_id ^ (count & is_atomic)) & outer); +} + +static int ipv6_gro_flush(const struct ipv6hdr *iph, const struct ipv6hdr *iph2) +{ + /* Version:4<Traffic_Class:8><Flow_Label:20> */ + __be32 first_word = *(__be32 *)iph ^ *(__be32 *)iph2; + + /* Flush if Traffic Class fields are different. */ + return (first_word & htonl(0x0FF00000)) | + (__force __be32)(iph->hop_limit ^ iph2->hop_limit); +} + +static int gro_network_flush(const void *nh, const void *nh2, + struct sk_buff *p, u32 outer) +{ + return (((struct iphdr *)nh)->version == 6) ? ipv6_gro_flush(nh, nh2) : + inet_gro_flush(nh, nh2, p, outer); +} + struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb) { struct sk_buff *pp = NULL; @@ -190,6 +239,7 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb) unsigned int mss = 1; unsigned int hlen; unsigned int off; + bool encap_mark; int flush = 1; int i;
@@ -232,9 +282,7 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb) goto out_check_final;
found: - /* Include the IP ID check below from the inner most IP hdr */ - flush = NAPI_GRO_CB(p)->flush; - flush |= (__force int)(flags & TCP_FLAG_CWR); + flush = (__force int)(flags & TCP_FLAG_CWR); flush |= (__force int)((flags ^ tcp_flag_word(th2)) & ~(TCP_FLAG_CWR | TCP_FLAG_FIN | TCP_FLAG_PSH)); flush |= (__force int)(th->ack_seq ^ th2->ack_seq); @@ -242,16 +290,14 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb) flush |= *(u32 *)((u8 *)th + i) ^ *(u32 *)((u8 *)th2 + i);
- /* When we receive our second frame we can made a decision on if we - * continue this flow as an atomic flow with a fixed ID or if we use - * an incrementing ID. - */ - if (NAPI_GRO_CB(p)->flush_id != 1 || - NAPI_GRO_CB(p)->count != 1 || - !NAPI_GRO_CB(p)->is_atomic) - flush |= NAPI_GRO_CB(p)->flush_id; - else - NAPI_GRO_CB(p)->is_atomic = false; + encap_mark = NAPI_GRO_CB(skb)->encap_mark; + for (i = 0; i <= encap_mark; i++) { + const u16 diff = off - NAPI_GRO_CB(skb)->network_offsets[i]; + + flush |= gro_network_flush((void *)th - diff, + (void *)th2 - diff, + p, i != encap_mark); + }
mss = skb_shinfo(p)->gso_size;
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index d9d3a6bed510..b1850c20d799 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -288,19 +288,8 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head, nlen - sizeof(struct ipv6hdr))) goto not_same_flow; } - /* flush if Traffic Class fields are different */ - NAPI_GRO_CB(p)->flush |= !!((first_word & htonl(0x0FF00000)) | - (__force __be32)(iph->hop_limit ^ iph2->hop_limit)); - NAPI_GRO_CB(p)->flush |= flush; - - /* If the previous IP ID value was based on an atomic - * datagram we can overwrite the value and ignore it. - */ - if (NAPI_GRO_CB(skb)->is_atomic) - NAPI_GRO_CB(p)->flush_id = 0; }
- NAPI_GRO_CB(skb)->is_atomic = true; NAPI_GRO_CB(skb)->flush |= flush;
skb_gro_postpull_rcsum(skb, iph, nlen);
On Sat, Mar 9, 2024 at 4:35 PM Richard Gobert richardbgobert@gmail.com wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
I do not think this claim is true.
Incoming packets -> GRO -> GSO -> forwarded packets
The {GRO,GSO} step must be transparent, GRO is not LRO.
Eric Dumazet wrote:
On Sat, Mar 9, 2024 at 4:35 PM Richard Gobert richardbgobert@gmail.com wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
I do not think this claim is true.
Incoming packets -> GRO -> GSO -> forwarded packets
The {GRO,GSO} step must be transparent, GRO is not LRO.
Sorry, I should rephrase myself. The patch preserves the current logic in GRO. These L3 checks (ttl, flags, etc.) are written to NAPI_GRO_CB(p)->{flush,flush_id}, and NAPI_GRO_CB(skb)->is_atomic - and all of these are currently used only in tcp_gro_receive.
Richard Gobert wrote:
Eric Dumazet wrote:
On Sat, Mar 9, 2024 at 4:35 PM Richard Gobert richardbgobert@gmail.com wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
I do not think this claim is true.
Incoming packets -> GRO -> GSO -> forwarded packets
The {GRO,GSO} step must be transparent, GRO is not LRO.
Sorry, I should rephrase myself. The patch preserves the current logic in GRO. These L3 checks (ttl, flags, etc.) are written to NAPI_GRO_CB(p)->{flush,flush_id}, and NAPI_GRO_CB(skb)->is_atomic - and all of these are currently used only in tcp_gro_receive.
That was perhaps an oversight when adding UDP GRO?
Simply because the flush is determined in the innermost callback.
Willem de Bruijn wrote:
Richard Gobert wrote:
Eric Dumazet wrote:
On Sat, Mar 9, 2024 at 4:35 PM Richard Gobert richardbgobert@gmail.com wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
I do not think this claim is true.
Incoming packets -> GRO -> GSO -> forwarded packets
The {GRO,GSO} step must be transparent, GRO is not LRO.
Sorry, I should rephrase myself. The patch preserves the current logic in GRO. These L3 checks (ttl, flags, etc.) are written to NAPI_GRO_CB(p)->{flush,flush_id}, and NAPI_GRO_CB(skb)->is_atomic - and all of these are currently used only in tcp_gro_receive.
That was perhaps an oversight when adding UDP GRO?
Simply because the flush is determined in the innermost callback.
It might have been an oversight. From what I have seen it's only relevant to GRO's UDP fraglist path (it was added in 9fd1ff5d ("udp: Support UDP fraglist GRO/GSO.")). That's the only UDP path that calls skb_gro_receive - which may alter the forwarded packets and make GRO/GSO not transparent.
AFAIU NAPI_GRO_CB(p)->flush value is not overwritten in encapsulation - it is determined by both outer and inner callbacks.
I tried to preserve the current behaviour in GRO - if we want to change this behaviour I'll gladly do it, although I'd prefer to address it in a different patch series. What do you think?
Thanks
Richard Gobert wrote:
Willem de Bruijn wrote:
Richard Gobert wrote:
Eric Dumazet wrote:
On Sat, Mar 9, 2024 at 4:35 PM Richard Gobert richardbgobert@gmail.com wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
I do not think this claim is true.
Incoming packets -> GRO -> GSO -> forwarded packets
The {GRO,GSO} step must be transparent, GRO is not LRO.
Sorry, I should rephrase myself. The patch preserves the current logic in GRO. These L3 checks (ttl, flags, etc.) are written to NAPI_GRO_CB(p)->{flush,flush_id}, and NAPI_GRO_CB(skb)->is_atomic - and all of these are currently used only in tcp_gro_receive.
That was perhaps an oversight when adding UDP GRO?
Simply because the flush is determined in the innermost callback.
It might have been an oversight. From what I have seen it's only relevant to GRO's UDP fraglist path (it was added in 9fd1ff5d ("udp: Support UDP fraglist GRO/GSO.")). That's the only UDP path that calls skb_gro_receive - which may alter the forwarded packets and make GRO/GSO not transparent.
AFAIU NAPI_GRO_CB(p)->flush value is not overwritten in encapsulation - it is determined by both outer and inner callbacks.
Thanks for the context
I tried to preserve the current behaviour in GRO - if we want to change this behaviour I'll gladly do it, although I'd prefer to address it in a different patch series. What do you think?
Yes, it's entirely reasonable to leave that out of this series.
Richard Gobert wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
These are network protocol coalescing invariants. Why would they be limited to certain transport protocols only?
Furthermore, they need to be done only once in tcp_gro_receive and only against the found p skb, since they only affect flush and not same_flow.
Levaraging the previous commit in the series, in which correct network header offsets are saved for both outer and inner network headers - allowing these checks to be done only once, in tcp_gro_receive. As a result, NAPI_GRO_CB(p)->flush is not used at all. In addition - flush_id checks are more declerative and contained in inet_gro_flush, thus removing
declarative
the need for flush_id in napi_gro_cb.
Signed-off-by: Richard Gobert richardbgobert@gmail.com
+static int inet_gro_flush(const struct iphdr *iph, const struct iphdr *iph2,
struct sk_buff *p, u32 outer)+{
- const u32 id = ntohl(*(__be32 *)&iph->id);
- const u32 id2 = ntohl(*(__be32 *)&iph2->id);
- const int flush_id = ntohs(id >> 16) - ntohs(id2 >> 16);
- const u16 count = NAPI_GRO_CB(p)->count;
- const u32 df = id & IP_DF;
- u32 is_atomic;
- int flush;
- /* All fields must match except length and checksum. */
- flush = (iph->ttl ^ iph2->ttl) | (iph->tos ^ iph2->tos) | (df ^ (id2 & IP_DF));
- /* When we receive our second frame we can make a decision on if we
* continue this flow as an atomic flow with a fixed ID or if we use* an incremdfenting ID.*/
Comment became garbled on move: incrementing
- if (count == 1) {
is_atomic = df && flush_id == 0;NAPI_GRO_CB(p)->is_atomic = is_atomic;- } else {
is_atomic = df && NAPI_GRO_CB(p)->is_atomic;- }
- /* Ignore outer IP ID value if based on atomic datagram. */
- outer = (outer && df) - 1;
- is_atomic--;
- return flush | ((flush_id ^ (count & is_atomic)) & outer);
+}
Willem de Bruijn wrote:
Richard Gobert wrote:
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are relevant only to tcp flows, and as such they're used to determine whether the packets can be merged later in tcp_gro_receive.
These checks are not relevant to UDP packets.
These are network protocol coalescing invariants. Why would they be limited to certain transport protocols only?
Thanks for the review, I'll fix the typos. I replied to Eric's comment about the relevancy of these checks for UDP.
linux-kselftest-mirror@lists.linaro.org
-
Eric Dumazet -
Richard Gobert -
Willem de Bruijn