From 919dfa0b20ae56060dce0436eb710717f8987d18 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 14 Nov 2022 13:57:53 -0800 Subject: [PATCH 1/5] udp: Clean up some functions. This patch adds no functional change and cleans up some functions that the following patches touch around so that we make them tidy and easy to review/revert. The change is mainly to keep reverse christmas tree order. Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- net/ipv4/udp.c | 39 +++++++++++++++++++++++---------------- net/ipv6/udp.c | 12 ++++++++---- 2 files changed, 31 insertions(+), 20 deletions(-) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index b859d6c8298e..a34de263e9ce 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -232,16 +232,16 @@ static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot) int udp_lib_get_port(struct sock *sk, unsigned short snum, unsigned int hash2_nulladdr) { - struct udp_hslot *hslot, *hslot2; struct udp_table *udptable = sk->sk_prot->h.udp_table; - int error = 1; + struct udp_hslot *hslot, *hslot2; struct net *net = sock_net(sk); + int error = 1; if (!snum) { + DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN); + unsigned short first, last; int low, high, remaining; unsigned int rand; - unsigned short first, last; - DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN); inet_get_local_port_range(net, &low, &high); remaining = (high - low) + 1; @@ -2519,10 +2519,13 @@ static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif) { - struct sock *sk, *result; unsigned short hnum = ntohs(loc_port); - unsigned int slot = udp_hashfn(net, hnum, udp_table.mask); - struct udp_hslot *hslot = &udp_table.hash[slot]; + struct sock *sk, *result; + struct udp_hslot *hslot; + unsigned int slot; + + slot = udp_hashfn(net, hnum, udp_table.mask); + hslot = &udp_table.hash[slot]; /* Do not bother scanning a too big list */ if (hslot->count > 10) @@ -2550,14 +2553,18 @@ static struct sock *__udp4_lib_demux_lookup(struct net *net, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif) { - unsigned short hnum = ntohs(loc_port); - unsigned int hash2 = ipv4_portaddr_hash(net, loc_addr, hnum); - unsigned int slot2 = hash2 & udp_table.mask; - struct udp_hslot *hslot2 = &udp_table.hash2[slot2]; INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr); - const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum); + unsigned short hnum = ntohs(loc_port); + unsigned int hash2, slot2; + struct udp_hslot *hslot2; + __portpair ports; struct sock *sk; + hash2 = ipv4_portaddr_hash(net, loc_addr, hnum); + slot2 = hash2 & udp_table.mask; + hslot2 = &udp_table.hash2[slot2]; + ports = INET_COMBINED_PORTS(rmt_port, hnum); + udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { if (inet_match(net, sk, acookie, ports, dif, sdif)) return sk; @@ -2970,10 +2977,10 @@ EXPORT_SYMBOL(udp_prot); static struct sock *udp_get_first(struct seq_file *seq, int start) { - struct sock *sk; - struct udp_seq_afinfo *afinfo; struct udp_iter_state *state = seq->private; struct net *net = seq_file_net(seq); + struct udp_seq_afinfo *afinfo; + struct sock *sk; if (state->bpf_seq_afinfo) afinfo = state->bpf_seq_afinfo; @@ -3004,9 +3011,9 @@ found: static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk) { - struct udp_seq_afinfo *afinfo; struct udp_iter_state *state = seq->private; struct net *net = seq_file_net(seq); + struct udp_seq_afinfo *afinfo; if (state->bpf_seq_afinfo) afinfo = state->bpf_seq_afinfo; @@ -3062,8 +3069,8 @@ EXPORT_SYMBOL(udp_seq_next); void udp_seq_stop(struct seq_file *seq, void *v) { - struct udp_seq_afinfo *afinfo; struct udp_iter_state *state = seq->private; + struct udp_seq_afinfo *afinfo; if (state->bpf_seq_afinfo) afinfo = state->bpf_seq_afinfo; diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index e2de3d906c82..727de67e4c90 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1064,12 +1064,16 @@ static struct sock *__udp6_lib_demux_lookup(struct net *net, int dif, int sdif) { unsigned short hnum = ntohs(loc_port); - unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum); - unsigned int slot2 = hash2 & udp_table.mask; - struct udp_hslot *hslot2 = &udp_table.hash2[slot2]; - const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum); + unsigned int hash2, slot2; + struct udp_hslot *hslot2; + __portpair ports; struct sock *sk; + hash2 = ipv6_portaddr_hash(net, loc_addr, hnum); + slot2 = hash2 & udp_table.mask; + hslot2 = &udp_table.hash2[slot2]; + ports = INET_COMBINED_PORTS(rmt_port, hnum); + udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { if (sk->sk_state == TCP_ESTABLISHED && inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif)) From 67fb43308f4b354f13aabcc66dd5d99bfbb7e838 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 14 Nov 2022 13:57:54 -0800 Subject: [PATCH 2/5] udp: Set NULL to sk->sk_prot->h.udp_table. We will soon introduce an optional per-netns hash table for UDP. This means we cannot use the global sk->sk_prot->h.udp_table to fetch a UDP hash table. Instead, set NULL to sk->sk_prot->h.udp_table for UDP and get a proper table from net->ipv4.udp_table. Note that we still need sk->sk_prot->h.udp_table for UDP LITE. Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- include/net/netns/ipv4.h | 1 + net/ipv4/udp.c | 15 +++++++++++---- net/ipv6/udp.c | 2 +- 3 files changed, 13 insertions(+), 5 deletions(-) diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index 25f90bba4889..e4cc4d3cacc4 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -43,6 +43,7 @@ struct tcp_fastopen_context; struct netns_ipv4 { struct inet_timewait_death_row tcp_death_row; + struct udp_table *udp_table; #ifdef CONFIG_SYSCTL struct ctl_table_header *forw_hdr; diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index a34de263e9ce..6206c27a1659 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -131,6 +131,11 @@ EXPORT_PER_CPU_SYMBOL_GPL(udp_memory_per_cpu_fw_alloc); #define MAX_UDP_PORTS 65536 #define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN) +static struct udp_table *udp_get_table_prot(struct sock *sk) +{ + return sk->sk_prot->h.udp_table ? : sock_net(sk)->ipv4.udp_table; +} + static int udp_lib_lport_inuse(struct net *net, __u16 num, const struct udp_hslot *hslot, unsigned long *bitmap, @@ -232,7 +237,7 @@ static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot) int udp_lib_get_port(struct sock *sk, unsigned short snum, unsigned int hash2_nulladdr) { - struct udp_table *udptable = sk->sk_prot->h.udp_table; + struct udp_table *udptable = udp_get_table_prot(sk); struct udp_hslot *hslot, *hslot2; struct net *net = sock_net(sk); int error = 1; @@ -1999,7 +2004,7 @@ EXPORT_SYMBOL(udp_disconnect); void udp_lib_unhash(struct sock *sk) { if (sk_hashed(sk)) { - struct udp_table *udptable = sk->sk_prot->h.udp_table; + struct udp_table *udptable = udp_get_table_prot(sk); struct udp_hslot *hslot, *hslot2; hslot = udp_hashslot(udptable, sock_net(sk), @@ -2030,7 +2035,7 @@ EXPORT_SYMBOL(udp_lib_unhash); void udp_lib_rehash(struct sock *sk, u16 newhash) { if (sk_hashed(sk)) { - struct udp_table *udptable = sk->sk_prot->h.udp_table; + struct udp_table *udptable = udp_get_table_prot(sk); struct udp_hslot *hslot, *hslot2, *nhslot2; hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash); @@ -2967,7 +2972,7 @@ struct proto udp_prot = { .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min), .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min), .obj_size = sizeof(struct udp_sock), - .h.udp_table = &udp_table, + .h.udp_table = NULL, .diag_destroy = udp_abort, }; EXPORT_SYMBOL(udp_prot); @@ -3280,6 +3285,8 @@ EXPORT_SYMBOL(udp_flow_hashrnd); static int __net_init udp_sysctl_init(struct net *net) { + net->ipv4.udp_table = &udp_table; + net->ipv4.sysctl_udp_rmem_min = PAGE_SIZE; net->ipv4.sysctl_udp_wmem_min = PAGE_SIZE; diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 727de67e4c90..bbd6dc398f3b 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1774,7 +1774,7 @@ struct proto udpv6_prot = { .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min), .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min), .obj_size = sizeof(struct udp6_sock), - .h.udp_table = &udp_table, + .h.udp_table = NULL, .diag_destroy = udp_abort, }; From 478aee5d6bf617c932f4e9c2981f17e86e093fc5 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 14 Nov 2022 13:57:55 -0800 Subject: [PATCH 3/5] udp: Set NULL to udp_seq_afinfo.udp_table. We will soon introduce an optional per-netns hash table for UDP. This means we cannot use the global udp_seq_afinfo.udp_table to fetch a UDP hash table. Instead, set NULL to udp_seq_afinfo.udp_table for UDP and get a proper table from net->ipv4.udp_table. Note that we still need udp_seq_afinfo.udp_table for UDP LITE. Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- net/ipv4/udp.c | 32 ++++++++++++++++++++++++-------- net/ipv6/udp.c | 2 +- 2 files changed, 25 insertions(+), 9 deletions(-) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 6206c27a1659..a1a15eb76304 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2980,11 +2980,18 @@ EXPORT_SYMBOL(udp_prot); /* ------------------------------------------------------------------------ */ #ifdef CONFIG_PROC_FS +static struct udp_table *udp_get_table_afinfo(struct udp_seq_afinfo *afinfo, + struct net *net) +{ + return afinfo->udp_table ? : net->ipv4.udp_table; +} + static struct sock *udp_get_first(struct seq_file *seq, int start) { struct udp_iter_state *state = seq->private; struct net *net = seq_file_net(seq); struct udp_seq_afinfo *afinfo; + struct udp_table *udptable; struct sock *sk; if (state->bpf_seq_afinfo) @@ -2992,9 +2999,11 @@ static struct sock *udp_get_first(struct seq_file *seq, int start) else afinfo = pde_data(file_inode(seq->file)); - for (state->bucket = start; state->bucket <= afinfo->udp_table->mask; + udptable = udp_get_table_afinfo(afinfo, net); + + for (state->bucket = start; state->bucket <= udptable->mask; ++state->bucket) { - struct udp_hslot *hslot = &afinfo->udp_table->hash[state->bucket]; + struct udp_hslot *hslot = &udptable->hash[state->bucket]; if (hlist_empty(&hslot->head)) continue; @@ -3019,6 +3028,7 @@ static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk) struct udp_iter_state *state = seq->private; struct net *net = seq_file_net(seq); struct udp_seq_afinfo *afinfo; + struct udp_table *udptable; if (state->bpf_seq_afinfo) afinfo = state->bpf_seq_afinfo; @@ -3032,8 +3042,11 @@ static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk) sk->sk_family != afinfo->family))); if (!sk) { - if (state->bucket <= afinfo->udp_table->mask) - spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock); + udptable = udp_get_table_afinfo(afinfo, net); + + if (state->bucket <= udptable->mask) + spin_unlock_bh(&udptable->hash[state->bucket].lock); + return udp_get_first(seq, state->bucket + 1); } return sk; @@ -3076,14 +3089,17 @@ void udp_seq_stop(struct seq_file *seq, void *v) { struct udp_iter_state *state = seq->private; struct udp_seq_afinfo *afinfo; + struct udp_table *udptable; if (state->bpf_seq_afinfo) afinfo = state->bpf_seq_afinfo; else afinfo = pde_data(file_inode(seq->file)); - if (state->bucket <= afinfo->udp_table->mask) - spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock); + udptable = udp_get_table_afinfo(afinfo, seq_file_net(seq)); + + if (state->bucket <= udptable->mask) + spin_unlock_bh(&udptable->hash[state->bucket].lock); } EXPORT_SYMBOL(udp_seq_stop); @@ -3196,7 +3212,7 @@ EXPORT_SYMBOL(udp_seq_ops); static struct udp_seq_afinfo udp4_seq_afinfo = { .family = AF_INET, - .udp_table = &udp_table, + .udp_table = NULL, }; static int __net_init udp4_proc_init_net(struct net *net) @@ -3316,7 +3332,7 @@ static int bpf_iter_init_udp(void *priv_data, struct bpf_iter_aux_info *aux) return -ENOMEM; afinfo->family = AF_UNSPEC; - afinfo->udp_table = &udp_table; + afinfo->udp_table = NULL; st->bpf_seq_afinfo = afinfo; ret = bpf_iter_init_seq_net(priv_data, aux); if (ret) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index bbd6dc398f3b..c3dee1f8d3bd 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1724,7 +1724,7 @@ EXPORT_SYMBOL(udp6_seq_ops); static struct udp_seq_afinfo udp6_seq_afinfo = { .family = AF_INET6, - .udp_table = &udp_table, + .udp_table = NULL, }; int __net_init udp6_proc_init(struct net *net) From ba6aac1516779dd0ced22c136a2c2c4a9c70cf29 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 14 Nov 2022 13:57:56 -0800 Subject: [PATCH 4/5] udp: Access &udp_table via net. We will soon introduce an optional per-netns hash table for UDP. This means we cannot use udp_table directly in most places. Instead, access it via net->ipv4.udp_table. The access will be valid only while initialising udp_table itself and creating/destroying each netns. Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- net/core/filter.c | 4 ++-- net/ipv4/udp.c | 23 +++++++++++++---------- net/ipv4/udp_diag.c | 6 +++--- net/ipv4/udp_offload.c | 5 +++-- net/ipv6/udp.c | 19 +++++++++++-------- net/ipv6/udp_offload.c | 5 +++-- 6 files changed, 35 insertions(+), 27 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 6dd2baf5eeb2..da4f697e4fa4 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -6432,7 +6432,7 @@ static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple, else sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport, dst4, tuple->ipv4.dport, - dif, sdif, &udp_table, NULL); + dif, sdif, net->ipv4.udp_table, NULL); #if IS_ENABLED(CONFIG_IPV6) } else { struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr; @@ -6448,7 +6448,7 @@ static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple, src6, tuple->ipv6.sport, dst6, tuple->ipv6.dport, dif, sdif, - &udp_table, NULL); + net->ipv4.udp_table, NULL); #endif } diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index a1a15eb76304..37e79158d145 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -472,7 +472,7 @@ static struct sock *udp4_lookup_run_bpf(struct net *net, struct sock *sk, *reuse_sk; bool no_reuseport; - if (udptable != &udp_table) + if (udptable != net->ipv4.udp_table) return NULL; /* only UDP is supported */ no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_UDP, saddr, sport, @@ -553,10 +553,11 @@ struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb, __be16 sport, __be16 dport) { const struct iphdr *iph = ip_hdr(skb); + struct net *net = dev_net(skb->dev); - return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport, + return __udp4_lib_lookup(net, iph->saddr, sport, iph->daddr, dport, inet_iif(skb), - inet_sdif(skb), &udp_table, NULL); + inet_sdif(skb), net->ipv4.udp_table, NULL); } /* Must be called under rcu_read_lock(). @@ -569,7 +570,7 @@ struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport, struct sock *sk; sk = __udp4_lib_lookup(net, saddr, sport, daddr, dport, - dif, 0, &udp_table, NULL); + dif, 0, net->ipv4.udp_table, NULL); if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) sk = NULL; return sk; @@ -807,7 +808,7 @@ out: int udp_err(struct sk_buff *skb, u32 info) { - return __udp4_lib_err(skb, info, &udp_table); + return __udp4_lib_err(skb, info, dev_net(skb->dev)->ipv4.udp_table); } /* @@ -2524,13 +2525,14 @@ static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif) { + struct udp_table *udptable = net->ipv4.udp_table; unsigned short hnum = ntohs(loc_port); struct sock *sk, *result; struct udp_hslot *hslot; unsigned int slot; - slot = udp_hashfn(net, hnum, udp_table.mask); - hslot = &udp_table.hash[slot]; + slot = udp_hashfn(net, hnum, udptable->mask); + hslot = &udptable->hash[slot]; /* Do not bother scanning a too big list */ if (hslot->count > 10) @@ -2558,6 +2560,7 @@ static struct sock *__udp4_lib_demux_lookup(struct net *net, __be16 rmt_port, __be32 rmt_addr, int dif, int sdif) { + struct udp_table *udptable = net->ipv4.udp_table; INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr); unsigned short hnum = ntohs(loc_port); unsigned int hash2, slot2; @@ -2566,8 +2569,8 @@ static struct sock *__udp4_lib_demux_lookup(struct net *net, struct sock *sk; hash2 = ipv4_portaddr_hash(net, loc_addr, hnum); - slot2 = hash2 & udp_table.mask; - hslot2 = &udp_table.hash2[slot2]; + slot2 = hash2 & udptable->mask; + hslot2 = &udptable->hash2[slot2]; ports = INET_COMBINED_PORTS(rmt_port, hnum); udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { @@ -2649,7 +2652,7 @@ int udp_v4_early_demux(struct sk_buff *skb) int udp_rcv(struct sk_buff *skb) { - return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP); + return __udp4_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP); } void udp_destroy_sock(struct sock *sk) diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c index 1ed8c4d78e5c..de3f2d31f510 100644 --- a/net/ipv4/udp_diag.c +++ b/net/ipv4/udp_diag.c @@ -147,13 +147,13 @@ done: static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r) { - udp_dump(&udp_table, skb, cb, r); + udp_dump(sock_net(cb->skb->sk)->ipv4.udp_table, skb, cb, r); } static int udp_diag_dump_one(struct netlink_callback *cb, const struct inet_diag_req_v2 *req) { - return udp_dump_one(&udp_table, cb, req); + return udp_dump_one(sock_net(cb->skb->sk)->ipv4.udp_table, cb, req); } static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, @@ -225,7 +225,7 @@ static int __udp_diag_destroy(struct sk_buff *in_skb, static int udp_diag_destroy(struct sk_buff *in_skb, const struct inet_diag_req_v2 *req) { - return __udp_diag_destroy(in_skb, req, &udp_table); + return __udp_diag_destroy(in_skb, req, sock_net(in_skb->sk)->ipv4.udp_table); } static int udplite_diag_destroy(struct sk_buff *in_skb, diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 6d1a4bec2614..aedde65e2268 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -600,10 +600,11 @@ static struct sock *udp4_gro_lookup_skb(struct sk_buff *skb, __be16 sport, __be16 dport) { const struct iphdr *iph = skb_gro_network_header(skb); + struct net *net = dev_net(skb->dev); - return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport, + return __udp4_lib_lookup(net, iph->saddr, sport, iph->daddr, dport, inet_iif(skb), - inet_sdif(skb), &udp_table, NULL); + inet_sdif(skb), net->ipv4.udp_table, NULL); } INDIRECT_CALLABLE_SCOPE diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index c3dee1f8d3bd..9fb2f33ee3a7 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -217,7 +217,7 @@ static inline struct sock *udp6_lookup_run_bpf(struct net *net, struct sock *sk, *reuse_sk; bool no_reuseport; - if (udptable != &udp_table) + if (udptable != net->ipv4.udp_table) return NULL; /* only UDP is supported */ no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP, saddr, sport, @@ -298,10 +298,11 @@ struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, __be16 sport, __be16 dport) { const struct ipv6hdr *iph = ipv6_hdr(skb); + struct net *net = dev_net(skb->dev); - return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport, + return __udp6_lib_lookup(net, &iph->saddr, sport, &iph->daddr, dport, inet6_iif(skb), - inet6_sdif(skb), &udp_table, NULL); + inet6_sdif(skb), net->ipv4.udp_table, NULL); } /* Must be called under rcu_read_lock(). @@ -314,7 +315,7 @@ struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be struct sock *sk; sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport, - dif, 0, &udp_table, NULL); + dif, 0, net->ipv4.udp_table, NULL); if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) sk = NULL; return sk; @@ -689,7 +690,8 @@ static __inline__ int udpv6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info) { - return __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); + return __udp6_lib_err(skb, opt, type, code, offset, info, + dev_net(skb->dev)->ipv4.udp_table); } static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb) @@ -1063,6 +1065,7 @@ static struct sock *__udp6_lib_demux_lookup(struct net *net, __be16 rmt_port, const struct in6_addr *rmt_addr, int dif, int sdif) { + struct udp_table *udptable = net->ipv4.udp_table; unsigned short hnum = ntohs(loc_port); unsigned int hash2, slot2; struct udp_hslot *hslot2; @@ -1070,8 +1073,8 @@ static struct sock *__udp6_lib_demux_lookup(struct net *net, struct sock *sk; hash2 = ipv6_portaddr_hash(net, loc_addr, hnum); - slot2 = hash2 & udp_table.mask; - hslot2 = &udp_table.hash2[slot2]; + slot2 = hash2 & udptable->mask; + hslot2 = &udptable->hash2[slot2]; ports = INET_COMBINED_PORTS(rmt_port, hnum); udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { @@ -1127,7 +1130,7 @@ void udp_v6_early_demux(struct sk_buff *skb) INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb) { - return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); + return __udp6_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP); } /* diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index 7720d04ed396..e0e10f6bcdc1 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -116,10 +116,11 @@ static struct sock *udp6_gro_lookup_skb(struct sk_buff *skb, __be16 sport, __be16 dport) { const struct ipv6hdr *iph = skb_gro_network_header(skb); + struct net *net = dev_net(skb->dev); - return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport, + return __udp6_lib_lookup(net, &iph->saddr, sport, &iph->daddr, dport, inet6_iif(skb), - inet6_sdif(skb), &udp_table, NULL); + inet6_sdif(skb), net->ipv4.udp_table, NULL); } INDIRECT_CALLABLE_SCOPE From 9804985bf27f8fbcf0d96c7435b5ad94a2a6ea20 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 14 Nov 2022 13:57:57 -0800 Subject: [PATCH 5/5] udp: Introduce optional per-netns hash table. The maximum hash table size is 64K due to the nature of the protocol. [0] It's smaller than TCP, and fewer sockets can cause a performance drop. On an EC2 c5.24xlarge instance (192 GiB memory), after running iperf3 in different netns, creating 32Mi sockets without data transfer in the root netns causes regression for the iperf3's connection. uhash_entries sockets length Gbps 64K 1 1 5.69 1Mi 16 5.27 2Mi 32 4.90 4Mi 64 4.09 8Mi 128 2.96 16Mi 256 2.06 32Mi 512 1.12 The per-netns hash table breaks the lengthy lists into shorter ones. It is useful on a multi-tenant system with thousands of netns. With smaller hash tables, we can look up sockets faster, isolate noisy neighbours, and reduce lock contention. The max size of the per-netns table is 64K as well. This is because the possible hash range by udp_hashfn() always fits in 64K within the same netns and we cannot make full use of the whole buckets larger than 64K. /* 0 < num < 64K -> X < hash < X + 64K */ (num + net_hash_mix(net)) & mask; Also, the min size is 128. We use a bitmap to search for an available port in udp_lib_get_port(). To keep the bitmap on the stack and not fire the CONFIG_FRAME_WARN error at build time, we round up the table size to 128. The sysctl usage is the same with TCP: $ dmesg | cut -d ' ' -f 6- | grep "UDP hash" UDP hash table entries: 65536 (order: 9, 2097152 bytes, vmalloc) # sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = 65536 # can be changed by uhash_entries # sysctl net.ipv4.udp_child_hash_entries net.ipv4.udp_child_hash_entries = 0 # disabled by default # ip netns add test1 # ip netns exec test1 sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = -65536 # share the global table # sysctl -w net.ipv4.udp_child_hash_entries=100 net.ipv4.udp_child_hash_entries = 100 # ip netns add test2 # ip netns exec test2 sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = 128 # own a per-netns table with 2^n buckets We could optimise the hash table lookup/iteration further by removing the netns comparison for the per-netns one in the future. Also, we could optimise the sparse udp_hslot layout by putting it in udp_table. [0]: https://lore.kernel.org/netdev/4ACC2815.7010101@gmail.com/ Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.rst | 27 +++++++ include/linux/udp.h | 2 + include/net/netns/ipv4.h | 2 + net/ipv4/sysctl_net_ipv4.c | 40 ++++++++++ net/ipv4/udp.c | 101 +++++++++++++++++++++++-- 5 files changed, 166 insertions(+), 6 deletions(-) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 815efc89ad73..727b25cc7ec4 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1177,6 +1177,33 @@ udp_rmem_min - INTEGER udp_wmem_min - INTEGER UDP does not have tx memory accounting and this tunable has no effect. +udp_hash_entries - INTEGER + Show the number of hash buckets for UDP sockets in the current + networking namespace. + + A negative value means the networking namespace does not own its + hash buckets and shares the initial networking namespace's one. + +udp_child_ehash_entries - INTEGER + Control the number of hash buckets for UDP sockets in the child + networking namespace, which must be set before clone() or unshare(). + + If the value is not 0, the kernel uses a value rounded up to 2^n + as the actual hash bucket size. 0 is a special value, meaning + the child networking namespace will share the initial networking + namespace's hash buckets. + + Note that the child will use the global one in case the kernel + fails to allocate enough memory. In addition, the global hash + buckets are spread over available NUMA nodes, but the allocation + of the child hash table depends on the current process's NUMA + policy, which could result in performance differences. + + Possible values: 0, 2^n (n: 7 (128) - 16 (64K)) + + Default: 0 + + RAW variables ============= diff --git a/include/linux/udp.h b/include/linux/udp.h index dea57aa37df6..a2892e151644 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -23,7 +23,9 @@ static inline struct udphdr *udp_hdr(const struct sk_buff *skb) return (struct udphdr *)skb_transport_header(skb); } +#define UDP_HTABLE_SIZE_MIN_PERNET 128 #define UDP_HTABLE_SIZE_MIN (CONFIG_BASE_SMALL ? 128 : 256) +#define UDP_HTABLE_SIZE_MAX 65536 static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask) { diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index e4cc4d3cacc4..db762e35aca9 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -208,6 +208,8 @@ struct netns_ipv4 { atomic_t dev_addr_genid; + unsigned int sysctl_udp_child_hash_entries; + #ifdef CONFIG_SYSCTL unsigned long *sysctl_local_reserved_ports; int sysctl_ip_prot_sock; diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 0af28cedd071..0d0cc4ef2b85 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -40,6 +40,7 @@ static int one_day_secs = 24 * 3600; static u32 fib_multipath_hash_fields_all_mask __maybe_unused = FIB_MULTIPATH_HASH_FIELD_ALL_MASK; static unsigned int tcp_child_ehash_entries_max = 16 * 1024 * 1024; +static unsigned int udp_child_hash_entries_max = UDP_HTABLE_SIZE_MAX; static int tcp_plb_max_rounds = 31; static int tcp_plb_max_cong_thresh = 256; @@ -402,12 +403,36 @@ static int proc_tcp_ehash_entries(struct ctl_table *table, int write, if (!net_eq(net, &init_net) && !hinfo->pernet) tcp_ehash_entries *= -1; + memset(&tbl, 0, sizeof(tbl)); tbl.data = &tcp_ehash_entries; tbl.maxlen = sizeof(int); return proc_dointvec(&tbl, write, buffer, lenp, ppos); } +static int proc_udp_hash_entries(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct net *net = container_of(table->data, struct net, + ipv4.sysctl_udp_child_hash_entries); + int udp_hash_entries; + struct ctl_table tbl; + + udp_hash_entries = net->ipv4.udp_table->mask + 1; + + /* A negative number indicates that the child netns + * shares the global udp_table. + */ + if (!net_eq(net, &init_net) && net->ipv4.udp_table == &udp_table) + udp_hash_entries *= -1; + + memset(&tbl, 0, sizeof(tbl)); + tbl.data = &udp_hash_entries; + tbl.maxlen = sizeof(int); + + return proc_dointvec(&tbl, write, buffer, lenp, ppos); +} + #ifdef CONFIG_IP_ROUTE_MULTIPATH static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write, void *buffer, size_t *lenp, @@ -1361,6 +1386,21 @@ static struct ctl_table ipv4_net_table[] = { .extra1 = SYSCTL_ZERO, .extra2 = &tcp_child_ehash_entries_max, }, + { + .procname = "udp_hash_entries", + .data = &init_net.ipv4.sysctl_udp_child_hash_entries, + .mode = 0444, + .proc_handler = proc_udp_hash_entries, + }, + { + .procname = "udp_child_hash_entries", + .data = &init_net.ipv4.sysctl_udp_child_hash_entries, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = &udp_child_hash_entries_max, + }, { .procname = "udp_rmem_min", .data = &init_net.ipv4.sysctl_udp_rmem_min, diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 37e79158d145..1fb7d1ed1cb1 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -129,7 +129,7 @@ DEFINE_PER_CPU(int, udp_memory_per_cpu_fw_alloc); EXPORT_PER_CPU_SYMBOL_GPL(udp_memory_per_cpu_fw_alloc); #define MAX_UDP_PORTS 65536 -#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN) +#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN_PERNET) static struct udp_table *udp_get_table_prot(struct sock *sk) { @@ -3277,7 +3277,7 @@ void __init udp_table_init(struct udp_table *table, const char *name) &table->log, &table->mask, UDP_HTABLE_SIZE_MIN, - 64 * 1024); + UDP_HTABLE_SIZE_MAX); table->hash2 = table->hash + (table->mask + 1); for (i = 0; i <= table->mask; i++) { @@ -3302,22 +3302,111 @@ u32 udp_flow_hashrnd(void) } EXPORT_SYMBOL(udp_flow_hashrnd); -static int __net_init udp_sysctl_init(struct net *net) +static void __net_init udp_sysctl_init(struct net *net) { - net->ipv4.udp_table = &udp_table; - net->ipv4.sysctl_udp_rmem_min = PAGE_SIZE; net->ipv4.sysctl_udp_wmem_min = PAGE_SIZE; #ifdef CONFIG_NET_L3_MASTER_DEV net->ipv4.sysctl_udp_l3mdev_accept = 0; #endif +} + +static struct udp_table __net_init *udp_pernet_table_alloc(unsigned int hash_entries) +{ + struct udp_table *udptable; + int i; + + udptable = kmalloc(sizeof(*udptable), GFP_KERNEL); + if (!udptable) + goto out; + + udptable->hash = vmalloc_huge(hash_entries * 2 * sizeof(struct udp_hslot), + GFP_KERNEL_ACCOUNT); + if (!udptable->hash) + goto free_table; + + udptable->hash2 = udptable->hash + hash_entries; + udptable->mask = hash_entries - 1; + udptable->log = ilog2(hash_entries); + + for (i = 0; i < hash_entries; i++) { + INIT_HLIST_HEAD(&udptable->hash[i].head); + udptable->hash[i].count = 0; + spin_lock_init(&udptable->hash[i].lock); + + INIT_HLIST_HEAD(&udptable->hash2[i].head); + udptable->hash2[i].count = 0; + spin_lock_init(&udptable->hash2[i].lock); + } + + return udptable; + +free_table: + kfree(udptable); +out: + return NULL; +} + +static void __net_exit udp_pernet_table_free(struct net *net) +{ + struct udp_table *udptable = net->ipv4.udp_table; + + if (udptable == &udp_table) + return; + + kvfree(udptable->hash); + kfree(udptable); +} + +static void __net_init udp_set_table(struct net *net) +{ + struct udp_table *udptable; + unsigned int hash_entries; + struct net *old_net; + + if (net_eq(net, &init_net)) + goto fallback; + + old_net = current->nsproxy->net_ns; + hash_entries = READ_ONCE(old_net->ipv4.sysctl_udp_child_hash_entries); + if (!hash_entries) + goto fallback; + + /* Set min to keep the bitmap on stack in udp_lib_get_port() */ + if (hash_entries < UDP_HTABLE_SIZE_MIN_PERNET) + hash_entries = UDP_HTABLE_SIZE_MIN_PERNET; + else + hash_entries = roundup_pow_of_two(hash_entries); + + udptable = udp_pernet_table_alloc(hash_entries); + if (udptable) { + net->ipv4.udp_table = udptable; + } else { + pr_warn("Failed to allocate UDP hash table (entries: %u) " + "for a netns, fallback to the global one\n", + hash_entries); +fallback: + net->ipv4.udp_table = &udp_table; + } +} + +static int __net_init udp_pernet_init(struct net *net) +{ + udp_sysctl_init(net); + udp_set_table(net); return 0; } +static void __net_exit udp_pernet_exit(struct net *net) +{ + udp_pernet_table_free(net); +} + static struct pernet_operations __net_initdata udp_sysctl_ops = { - .init = udp_sysctl_init, + .init = udp_pernet_init, + .exit = udp_pernet_exit, }; #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)