Commit f86f42ed authored by Eric Dumazet's avatar Eric Dumazet Committed by Paolo Abeni
Browse files

net: add sk_drops_read(), sk_drops_inc() and sk_drops_reset() helpers 



We want to split sk->sk_drops in the future to reduce
potential contention on this field.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarKuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250826125031.1578842-2-edumazet@google.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent c2a75689

include/net/sock.h

+16 −1
Original line number Diff line number Diff line
@@ -2682,11 +2682,26 @@ struct sock_skb_cb { 
#define sock_skb_cb_check_size(size) \

	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)



static inline void sk_drops_inc(struct sock *sk)

{

	atomic_inc(&sk->sk_drops);

}



static inline int sk_drops_read(const struct sock *sk)

{

	return atomic_read(&sk->sk_drops);

}



static inline void sk_drops_reset(struct sock *sk)

{

	atomic_set(&sk->sk_drops, 0);

}



static inline void

sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)

{

	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?

						atomic_read(&sk->sk_drops) : 0;

						sk_drops_read(sk) : 0;

}



static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)

include/net/tcp.h

+1 −1
Original line number Diff line number Diff line
@@ -2612,7 +2612,7 @@ static inline void tcp_segs_in(struct tcp_sock *tp, const struct sk_buff *skb) 
 */

static inline void tcp_listendrop(const struct sock *sk)

{

	atomic_inc(&((struct sock *)sk)->sk_drops);

	sk_drops_inc((struct sock *)sk);

	__NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS);

}

net/core/datagram.c

+1 −1
Original line number Diff line number Diff line
@@ -345,7 +345,7 @@ int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 
		spin_unlock_bh(&sk_queue->lock);

	}



	atomic_inc(&sk->sk_drops);

	sk_drops_inc(sk);

	return err;

}

EXPORT_SYMBOL(__sk_queue_drop_skb);

net/core/sock.c

+7 −7
Original line number Diff line number Diff line
@@ -491,13 +491,13 @@ int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 
	struct sk_buff_head *list = &sk->sk_receive_queue;



	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {

		atomic_inc(&sk->sk_drops);

		sk_drops_inc(sk);

		trace_sock_rcvqueue_full(sk, skb);

		return -ENOMEM;

	}



	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {

		atomic_inc(&sk->sk_drops);

		sk_drops_inc(sk);

		return -ENOBUFS;

	}
@@ -562,7 +562,7 @@ int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 
	skb->dev = NULL;



	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {

		atomic_inc(&sk->sk_drops);

		sk_drops_inc(sk);

		reason = SKB_DROP_REASON_SOCKET_RCVBUFF;

		goto discard_and_relse;

	}
@@ -585,7 +585,7 @@ int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 
			reason = SKB_DROP_REASON_PFMEMALLOC;

		if (err == -ENOBUFS)

			reason = SKB_DROP_REASON_SOCKET_BACKLOG;

		atomic_inc(&sk->sk_drops);

		sk_drops_inc(sk);

		goto discard_and_relse;

	}
@@ -2505,7 +2505,7 @@ struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 
	newsk->sk_wmem_queued	= 0;

	newsk->sk_forward_alloc = 0;

	newsk->sk_reserved_mem  = 0;

	atomic_set(&newsk->sk_drops, 0);

	sk_drops_reset(newsk);

	newsk->sk_send_head	= NULL;

	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;

	atomic_set(&newsk->sk_zckey, 0);
@@ -3713,7 +3713,7 @@ void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid) 
	 */

	smp_wmb();

	refcount_set(&sk->sk_refcnt, 1);

	atomic_set(&sk->sk_drops, 0);

	sk_drops_reset(sk);

}

EXPORT_SYMBOL(sock_init_data_uid);
@@ -3973,7 +3973,7 @@ void sk_get_meminfo(const struct sock *sk, u32 *mem) 
	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);

	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);

	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);

	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);

	mem[SK_MEMINFO_DROPS] = sk_drops_read(sk);

}



#ifdef CONFIG_PROC_FS

net/ipv4/ping.c

+1 −1
Original line number Diff line number Diff line
@@ -1119,7 +1119,7 @@ static void ping_v4_format_sock(struct sock *sp, struct seq_file *f, 
		from_kuid_munged(seq_user_ns(f), sk_uid(sp)),

		0, sock_i_ino(sp),

		refcount_read(&sp->sk_refcnt), sp,

		atomic_read(&sp->sk_drops));

		sk_drops_read(sp));

}



static int ping_v4_seq_show(struct seq_file *seq, void *v)