Commit 43312915 authored by Cong Wang's avatar Cong Wang Committed by Daniel Borkmann
Browse files

skmsg: Get rid of unncessary memset() 



We always allocate skmsg with kzalloc(), so there is no need
to call memset(0) on it, the only thing we need from
sk_msg_init() is sg_init_marker(). So introduce a new helper
which is just kzalloc()+sg_init_marker(), this saves an
unncessary memset(0) for skmsg on fast path.

Signed-off-by: default avatarCong Wang <cong.wang@bytedance.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220615162014.89193-5-xiyou.wangcong@gmail.com
parent 57452d76

net/core/skmsg.c

+13 −10
Original line number Diff line number Diff line
@@ -497,23 +497,27 @@ bool sk_msg_is_readable(struct sock *sk) 
}

EXPORT_SYMBOL_GPL(sk_msg_is_readable);



static struct sk_msg *sk_psock_create_ingress_msg(struct sock *sk,

						  struct sk_buff *skb)

static struct sk_msg *alloc_sk_msg(void)

{

	struct sk_msg *msg;



	if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf)

	msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_KERNEL);

	if (unlikely(!msg))

		return NULL;

	sg_init_marker(msg->sg.data, NR_MSG_FRAG_IDS);

	return msg;

}



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

static struct sk_msg *sk_psock_create_ingress_msg(struct sock *sk,

						  struct sk_buff *skb)

{

	if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf)

		return NULL;



	msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_KERNEL);

	if (unlikely(!msg))

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

		return NULL;



	sk_msg_init(msg);

	return msg;

	return alloc_sk_msg();

}



static int sk_psock_skb_ingress_enqueue(struct sk_buff *skb,
@@ -590,13 +594,12 @@ static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb, 
static int sk_psock_skb_ingress_self(struct sk_psock *psock, struct sk_buff *skb,

				     u32 off, u32 len)

{

	struct sk_msg *msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_ATOMIC);

	struct sk_msg *msg = alloc_sk_msg();

	struct sock *sk = psock->sk;

	int err;



	if (unlikely(!msg))

		return -EAGAIN;

	sk_msg_init(msg);

	skb_set_owner_r(skb, sk);

	err = sk_psock_skb_ingress_enqueue(skb, off, len, psock, sk, msg);

	if (err < 0)