Commit 46173144 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

net: mark deliver_skb() as unlikely and not inlined 



deliver_skb() should not be inlined as is it not called
in the fast path.

Add unlikely() clauses giving hints to the compiler about this fact.

Before this patch:

size net/core/dev.o
   text	   data	    bss	    dec	    hex	filename
 121794	  13330	    176	 135300	  21084	net/core/dev.o

__netif_receive_skb_core() size on x86_64 : 4080 bytes.

After:

size net/core/dev.o
  text	   data	    bss	    dec	    hex	filenamee
 120330	  13338	    176	 133844	  20ad4	net/core/dev.o

__netif_receive_skb_core() size on x86_64 : 2781 bytes.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251103165256.1712169-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 105bae32

net/core/dev.c

+11 −11
Original line number Diff line number Diff line
@@ -2463,7 +2463,7 @@ int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 
	return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb);

}



static inline int deliver_skb(struct sk_buff *skb,

static int deliver_skb(struct sk_buff *skb,

		       struct packet_type *pt_prev,

		       struct net_device *orig_dev)

{
@@ -2484,7 +2484,7 @@ static inline void deliver_ptype_list_skb(struct sk_buff *skb, 
	list_for_each_entry_rcu(ptype, ptype_list, list) {

		if (ptype->type != type)

			continue;

		if (pt_prev)

		if (unlikely(pt_prev))

			deliver_skb(skb, pt_prev, orig_dev);

		pt_prev = ptype;

	}
@@ -2545,7 +2545,7 @@ void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 
		if (skb_loop_sk(ptype, skb))

			continue;



		if (pt_prev) {

		if (unlikely(pt_prev)) {

			deliver_skb(skb2, pt_prev, skb->dev);

			pt_prev = ptype;

			continue;
@@ -4421,7 +4421,7 @@ sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 
		return skb;



	bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);

	if (*pt_prev) {

	if (unlikely(*pt_prev)) {

		*ret = deliver_skb(skb, *pt_prev, orig_dev);

		*pt_prev = NULL;

	}
@@ -5883,7 +5883,7 @@ static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 
	if (nf_hook_ingress_active(skb)) {

		int ingress_retval;



		if (*pt_prev) {

		if (unlikely(*pt_prev)) {

			*ret = deliver_skb(skb, *pt_prev, orig_dev);

			*pt_prev = NULL;

		}
@@ -5960,13 +5960,13 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 


	list_for_each_entry_rcu(ptype, &dev_net_rcu(skb->dev)->ptype_all,

				list) {

		if (pt_prev)

		if (unlikely(pt_prev))

			ret = deliver_skb(skb, pt_prev, orig_dev);

		pt_prev = ptype;

	}



	list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {

		if (pt_prev)

		if (unlikely(pt_prev))

			ret = deliver_skb(skb, pt_prev, orig_dev);

		pt_prev = ptype;

	}
@@ -5997,7 +5997,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 
	}



	if (skb_vlan_tag_present(skb)) {

		if (pt_prev) {

		if (unlikely(pt_prev)) {

			ret = deliver_skb(skb, pt_prev, orig_dev);

			pt_prev = NULL;

		}
@@ -6009,7 +6009,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 


	rx_handler = rcu_dereference(skb->dev->rx_handler);

	if (rx_handler) {

		if (pt_prev) {

		if (unlikely(pt_prev)) {

			ret = deliver_skb(skb, pt_prev, orig_dev);

			pt_prev = NULL;

		}