All of lore.kernel.org
 help / color / mirror / Atom feed
From: Martin KaFai Lau <kafai@fb.com>
To: <bpf@vger.kernel.org>, <netdev@vger.kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>,
	Andrii Nakryiko <andrii@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	David Miller <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, <kernel-team@fb.com>,
	Willem de Bruijn <willemb@google.com>
Subject: [RFC PATCH v3 net-next 2/4] net: Add skb_clear_tstamp() to keep the mono delivery_time
Date: Thu, 20 Jan 2022 23:30:38 -0800	[thread overview]
Message-ID: <20220121073038.4178331-1-kafai@fb.com> (raw)
In-Reply-To: <20220121073026.4173996-1-kafai@fb.com>

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 clear everything else.

The delivery_time clearing is postponed until the stack knows the
skb will be delivered locally.  The postponed delivery_time clearing
will be done together in a later patch when the skb->mono_delivery_time
bit will finally be turned on.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
---
 drivers/net/loopback.c           |  2 +-
 include/linux/skbuff.h           | 10 +++++++++-
 net/bridge/br_forward.c          |  2 +-
 net/core/filter.c                |  6 +++---
 net/core/skbuff.c                |  2 +-
 net/ipv4/ip_forward.c            |  2 +-
 net/ipv6/ip6_output.c            |  2 +-
 net/netfilter/ipvs/ip_vs_xmit.c  |  6 +++---
 net/netfilter/nf_dup_netdev.c    |  2 +-
 net/netfilter/nf_flow_table_ip.c |  4 ++--
 net/netfilter/nft_fwd_netdev.c   |  2 +-
 net/openvswitch/vport.c          |  2 +-
 net/xfrm/xfrm_interface.c        |  2 +-
 13 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index ed0edf5884ef..70a38fa09299 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -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);
 
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index b9e20187242a..8de555513b94 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3916,6 +3916,14 @@ static inline void skb_set_delivery_time(struct sk_buff *skb, ktime_t kt,
 	/* skb->mono_delivery_time = kt && mono; */
 }
 
+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;
@@ -4772,7 +4780,7 @@ 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
 }
 
diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
index ec646656dbf1..02bb620d3b8d 100644
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c
@@ -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);
diff --git a/net/core/filter.c b/net/core/filter.c
index 4603b7cd3cd1..4fc53d645a01 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -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);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 0118f0afaa4f..3e3da8fdf8f5 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -5350,7 +5350,7 @@ 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);
 
diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
index 00ec819f949b..92ba3350274b 100644
--- a/net/ipv4/ip_forward.c
+++ b/net/ipv4/ip_forward.c
@@ -79,7 +79,7 @@ static int ip_forward_finish(struct net *net, struct sock *sk, struct sk_buff *s
 	if (unlikely(opt->optlen))
 		ip_forward_options(skb);
 
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 	return dst_output(net, sk, skb);
 }
 
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 4b873413edc2..0875ab61eb95 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -440,7 +440,7 @@ static inline int ip6_forward_finish(struct net *net, struct sock *sk,
 	}
 #endif
 
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 	return dst_output(net, sk, skb);
 }
 
diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c
index d2e5a8f644b8..029171379884 100644
--- a/net/netfilter/ipvs/ip_vs_xmit.c
+++ b/net/netfilter/ipvs/ip_vs_xmit.c
@@ -610,7 +610,7 @@ static inline int ip_vs_tunnel_xmit_prepare(struct sk_buff *skb,
 		nf_reset_ct(skb);
 		skb_forward_csum(skb);
 		if (skb->dev)
-			skb->tstamp = 0;
+			skb_clear_tstamp(skb);
 	}
 	return ret;
 }
@@ -652,7 +652,7 @@ static inline int ip_vs_nat_send_or_cont(int pf, struct sk_buff *skb,
 	if (!local) {
 		skb_forward_csum(skb);
 		if (skb->dev)
-			skb->tstamp = 0;
+			skb_clear_tstamp(skb);
 		NF_HOOK(pf, NF_INET_LOCAL_OUT, cp->ipvs->net, NULL, skb,
 			NULL, skb_dst(skb)->dev, dst_output);
 	} else
@@ -674,7 +674,7 @@ static inline int ip_vs_send_or_cont(int pf, struct sk_buff *skb,
 		ip_vs_drop_early_demux_sk(skb);
 		skb_forward_csum(skb);
 		if (skb->dev)
-			skb->tstamp = 0;
+			skb_clear_tstamp(skb);
 		NF_HOOK(pf, NF_INET_LOCAL_OUT, cp->ipvs->net, NULL, skb,
 			NULL, skb_dst(skb)->dev, dst_output);
 	} else
diff --git a/net/netfilter/nf_dup_netdev.c b/net/netfilter/nf_dup_netdev.c
index a579e59ee5c5..7873bd1389c3 100644
--- a/net/netfilter/nf_dup_netdev.c
+++ b/net/netfilter/nf_dup_netdev.c
@@ -19,7 +19,7 @@ static void nf_do_netdev_egress(struct sk_buff *skb, struct net_device *dev)
 		skb_push(skb, skb->mac_len);
 
 	skb->dev = dev;
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 	dev_queue_xmit(skb);
 }
 
diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 889cf88d3dba..f1d387129f02 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -376,7 +376,7 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
 	nf_flow_nat_ip(flow, skb, thoff, dir, iph);
 
 	ip_decrease_ttl(iph);
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 
 	if (flow_table->flags & NF_FLOWTABLE_COUNTER)
 		nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
@@ -611,7 +611,7 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
 	nf_flow_nat_ipv6(flow, skb, dir, ip6h);
 
 	ip6h->hop_limit--;
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 
 	if (flow_table->flags & NF_FLOWTABLE_COUNTER)
 		nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
diff --git a/net/netfilter/nft_fwd_netdev.c b/net/netfilter/nft_fwd_netdev.c
index fa9301ca6033..4b2b0946c0b6 100644
--- a/net/netfilter/nft_fwd_netdev.c
+++ b/net/netfilter/nft_fwd_netdev.c
@@ -140,7 +140,7 @@ static void nft_fwd_neigh_eval(const struct nft_expr *expr,
 		return;
 
 	skb->dev = dev;
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 	neigh_xmit(neigh_table, dev, addr, skb);
 out:
 	regs->verdict.code = verdict;
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index cf2ce5812489..82a74f998966 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -507,7 +507,7 @@ void ovs_vport_send(struct vport *vport, struct sk_buff *skb, u8 mac_proto)
 	}
 
 	skb->dev = vport->dev;
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 	vport->ops->send(skb);
 	return;
 
diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index 57448fc519fc..4991e99ced9a 100644
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -190,7 +190,7 @@ static void xfrmi_dev_uninit(struct net_device *dev)
 
 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
 {
-	skb->tstamp = 0;
+	skb_clear_tstamp(skb);
 	skb->pkt_type = PACKET_HOST;
 	skb->skb_iif = 0;
 	skb->ignore_df = 0;
-- 
2.30.2


  parent reply	other threads:[~2022-01-21  7:30 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-21  7:30 [RFC PATCH v3 net-next 0/4] Preserve mono delivery time (EDT) in skb->tstamp Martin KaFai Lau
2022-01-21  7:30 ` [RFC PATCH v3 net-next 1/4] net: Add skb->mono_delivery_time to distinguish mono delivery_time from (rcv) timestamp Martin KaFai Lau
2022-01-22 15:32   ` Willem de Bruijn
2022-01-22 19:52     ` Martin KaFai Lau
2022-01-22 20:03     ` Martin KaFai Lau
2022-01-21  7:30 ` Martin KaFai Lau [this message]
2022-01-21  7:30 ` [RFC PATCH v3 net-next 3/4] net: Set skb->mono_delivery_time and clear it when delivering locally Martin KaFai Lau
2022-01-21 12:02   ` Julian Anastasov
2022-01-22  3:28     ` Martin KaFai Lau
2022-01-21  7:30 ` [RFC PATCH v3 net-next 4/4] bpf: Add __sk_buff->mono_delivery_time and handle __sk_buff->tstamp based on tc_at_ingress Martin KaFai Lau
2022-01-21 18:50   ` sdf
2022-01-21 20:56     ` Martin KaFai Lau
2022-01-21 22:33       ` sdf
2022-01-22 15:43 ` [RFC PATCH v3 net-next 0/4] Preserve mono delivery time (EDT) in skb->tstamp Willem de Bruijn
2022-01-22 21:05   ` Martin KaFai Lau

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220121073038.4178331-1-kafai@fb.com \
    --to=kafai@fb.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=kernel-team@fb.com \
    --cc=kuba@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=willemb@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.