Commit dbd5e2e7 authored by Yafang Shao's avatar Yafang Shao Committed by Jakub Kicinski
Browse files

net: tcp: Add noinline_for_tracing annotation for tcp_drop_reason() 

We previously hooked the tcp_drop_reason() function using BPF to monitor
TCP drop reasons. However, after upgrading our compiler from GCC 9 to GCC
11, tcp_drop_reason() is now inlined, preventing us from hooking into it.
To address this, it would be beneficial to make noinline explicitly for
tracing.

Link: https://lore.kernel.org/netdev/CANn89iJuShCmidCi_ZkYABtmscwbVjhuDta1MS5LxV_4H9tKOA@mail.gmail.com/


Suggested-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarYafang Shao <laoar.shao@gmail.com>
Cc: Menglong Dong <menglong8.dong@gmail.com>
Link: https://patch.msgid.link/20241024093742.87681-3-laoar.shao@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent a8f80673

net/ipv4/tcp_input.c

+2 −2
Original line number Diff line number Diff line
@@ -4921,8 +4921,8 @@ static bool tcp_ooo_try_coalesce(struct sock *sk, 
	return res;

}



static void tcp_drop_reason(struct sock *sk, struct sk_buff *skb,

			    enum skb_drop_reason reason)

noinline_for_tracing static void

tcp_drop_reason(struct sock *sk, struct sk_buff *skb, enum skb_drop_reason reason)

{

	sk_drops_add(sk, skb);

	sk_skb_reason_drop(sk, skb, reason);