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| author | Eric Dumazet <edumazet@google.com> | 2024-12-15 17:56:29 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-12-17 19:37:48 -0800 |
| commit | a853c609504e2d1d83e71285e3622fda1f1451d8 (patch) | |
| tree | b6d9cd4e2333cf6afc87beb0bc7675bc73777006 /net/ipv6 | |
| parent | 50b362f21d6c10b0f7939c1482c6a1b43da82f1a (diff) | |
| download | linux-a853c609504e2d1d83e71285e3622fda1f1451d8.tar.gz linux-a853c609504e2d1d83e71285e3622fda1f1451d8.tar.bz2 linux-a853c609504e2d1d83e71285e3622fda1f1451d8.zip | |
inetpeer: do not get a refcount in inet_getpeer()
All inet_getpeer() callers except ip4_frag_init() don't need
to acquire a permanent refcount on the inetpeer.
They can switch to full RCU protection.
Move the refcount_inc_not_zero() into ip4_frag_init(),
so that all the other callers no longer have to
perform a pair of expensive atomic operations on
a possibly contended cache line.
inet_putpeer() no longer needs to be exported.
After this patch, my DUT can receive 8,400,000 UDP packets
per second targeting closed ports, using 50% less cpu cycles
than before.
Also change two calls to l3mdev_master_ifindex() by
l3mdev_master_ifindex_rcu() (Ido ideas)
Fixes: 8c2bd38b95f7 ("icmp: change the order of rate limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241215175629.1248773-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/icmp.c | 4 | ||||
| -rw-r--r-- | net/ipv6/ip6_output.c | 4 | ||||
| -rw-r--r-- | net/ipv6/ndisc.c | 6 |
3 files changed, 8 insertions, 6 deletions
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index 4593e3992c67..a6984a29fdb9 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -222,10 +222,10 @@ static bool icmpv6_xrlim_allow(struct sock *sk, u8 type, if (rt->rt6i_dst.plen < 128) tmo >>= ((128 - rt->rt6i_dst.plen)>>5); + rcu_read_lock(); peer = inet_getpeer_v6(net->ipv6.peers, &fl6->daddr); res = inet_peer_xrlim_allow(peer, tmo); - if (peer) - inet_putpeer(peer); + rcu_read_unlock(); } if (!res) __ICMP6_INC_STATS(net, ip6_dst_idev(dst), diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index cdcbb3b6c5da..d577bf2f3053 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -613,6 +613,7 @@ int ip6_forward(struct sk_buff *skb) else target = &hdr->daddr; + rcu_read_lock(); peer = inet_getpeer_v6(net->ipv6.peers, &hdr->daddr); /* Limit redirects both by destination (here) @@ -620,8 +621,7 @@ int ip6_forward(struct sk_buff *skb) */ if (inet_peer_xrlim_allow(peer, 1*HZ)) ndisc_send_redirect(skb, target); - if (peer) - inet_putpeer(peer); + rcu_read_unlock(); } else { int addrtype = ipv6_addr_type(&hdr->saddr); diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index f113554d1332..d044c67019de 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1731,10 +1731,12 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) "Redirect: destination is not a neighbour\n"); goto release; } + + rcu_read_lock(); peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr); ret = inet_peer_xrlim_allow(peer, 1*HZ); - if (peer) - inet_putpeer(peer); + rcu_read_unlock(); + if (!ret) goto release; |