Commit de799101 authored by Martin KaFai Lau's avatar Martin KaFai Lau Committed by David S. Miller
Browse files

net: Add skb_clear_tstamp() to keep the mono delivery_time 



Right now, skb->tstamp is reset to 0 whenever the skb is forwarded.

If skb->tstamp has the mono delivery_time, clearing it can hurt
the performance when it finally transmits out to fq@phy-dev.

The earlier patch added a skb->mono_delivery_time bit to
flag the skb->tstamp carrying the mono delivery_time.

This patch adds skb_clear_tstamp() helper which keeps
the mono delivery_time and clears everything else.

The delivery_time clearing will be postponed until the stack knows the
skb will be delivered locally.  It will be done in a latter patch.

Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a1ac9c8a

drivers/net/loopback.c

+1 −1
Original line number Diff line number Diff line
@@ -74,7 +74,7 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, 
	skb_tx_timestamp(skb);



	/* do not fool net_timestamp_check() with various clock bases */

	skb->tstamp = 0;

	skb_clear_tstamp(skb);



	skb_orphan(skb);

include/linux/skbuff.h

+9 −1
Original line number Diff line number Diff line
@@ -3996,6 +3996,14 @@ static inline void skb_set_delivery_time(struct sk_buff *skb, ktime_t kt, 
	skb->mono_delivery_time = 0;

}



static inline void skb_clear_tstamp(struct sk_buff *skb)

{

	if (skb->mono_delivery_time)

		return;



	skb->tstamp = 0;

}



static inline u8 skb_metadata_len(const struct sk_buff *skb)

{

	return skb_shinfo(skb)->meta_len;
@@ -4852,7 +4860,7 @@ static inline void skb_set_redirected(struct sk_buff *skb, bool from_ingress) 
#ifdef CONFIG_NET_REDIRECT

	skb->from_ingress = from_ingress;

	if (skb->from_ingress)

		skb->tstamp = 0;

		skb_clear_tstamp(skb);

#endif

}

net/bridge/br_forward.c

+1 −1
Original line number Diff line number Diff line
@@ -62,7 +62,7 @@ EXPORT_SYMBOL_GPL(br_dev_queue_push_xmit); 


int br_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)

{

	skb->tstamp = 0;

	skb_clear_tstamp(skb);

	return NF_HOOK(NFPROTO_BRIDGE, NF_BR_POST_ROUTING,

		       net, sk, skb, NULL, skb->dev,

		       br_dev_queue_push_xmit);

net/core/filter.c

+3 −3
Original line number Diff line number Diff line
@@ -2107,7 +2107,7 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) 
	}



	skb->dev = dev;

	skb->tstamp = 0;

	skb_clear_tstamp(skb);



	dev_xmit_recursion_inc();

	ret = dev_queue_xmit(skb);
@@ -2176,7 +2176,7 @@ static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb, 
	}



	skb->dev = dev;

	skb->tstamp = 0;

	skb_clear_tstamp(skb);



	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {

		skb = skb_expand_head(skb, hh_len);
@@ -2274,7 +2274,7 @@ static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb, 
	}



	skb->dev = dev;

	skb->tstamp = 0;

	skb_clear_tstamp(skb);



	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {

		skb = skb_expand_head(skb, hh_len);

net/core/skbuff.c

+1 −1
Original line number Diff line number Diff line
@@ -5381,7 +5381,7 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet) 


	ipvs_reset(skb);

	skb->mark = 0;

	skb->tstamp = 0;

	skb_clear_tstamp(skb);

}

EXPORT_SYMBOL_GPL(skb_scrub_packet);