From 7a26dc9e7b43f5a24c4b843713e728582adf1c38 Mon Sep 17 00:00:00 2001 From: Menglong Dong Date: Sun, 20 Feb 2022 15:06:33 +0800 Subject: net: tcp: add skb drop reasons to tcp_add_backlog() Pass the address of drop_reason to tcp_add_backlog() to store the reasons for skb drops when fails. Following drop reasons are introduced: SKB_DROP_REASON_SOCKET_BACKLOG Reviewed-by: Mengen Sun Reviewed-by: Hao Peng Signed-off-by: Menglong Dong Reviewed-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index d3c417119057..cbca8637ba2f 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1811,7 +1811,8 @@ int tcp_v4_early_demux(struct sk_buff *skb) return 0; } -bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) +bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb, + enum skb_drop_reason *reason) { u32 limit, tail_gso_size, tail_gso_segs; struct skb_shared_info *shinfo; @@ -1837,6 +1838,7 @@ bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) if (unlikely(tcp_checksum_complete(skb))) { bh_unlock_sock(sk); trace_tcp_bad_csum(skb); + *reason = SKB_DROP_REASON_TCP_CSUM; __TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); __TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); return true; @@ -1925,6 +1927,7 @@ no_coalesce: if (unlikely(sk_add_backlog(sk, skb, limit))) { bh_unlock_sock(sk); + *reason = SKB_DROP_REASON_SOCKET_BACKLOG; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); return true; } @@ -2133,7 +2136,7 @@ process: if (!sock_owned_by_user(sk)) { ret = tcp_v4_do_rcv(sk, skb); } else { - if (tcp_add_backlog(sk, skb)) + if (tcp_add_backlog(sk, skb, &drop_reason)) goto discard_and_relse; } bh_unlock_sock(sk); -- cgit v1.2.3