From: Eric Dumazet <eric.dumazet@gmail.com>
To: "David S . Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>
Cc: netdev <netdev@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
Eric Dumazet <eric.dumazet@gmail.com>
Subject: [PATCH net-next 1/2] gro: remove rcu_read_lock/rcu_read_unlock from gro_receive handlers
Date: Tue, 23 Nov 2021 14:56:07 -0800 [thread overview]
Message-ID: <20211123225608.2155163-2-eric.dumazet@gmail.com> (raw)
In-Reply-To: <20211123225608.2155163-1-eric.dumazet@gmail.com>
From: Eric Dumazet <edumazet@google.com>
All gro_receive() handlers are called from dev_gro_receive()
while rcu_read_lock() has been called.
There is no point stacking more rcu_read_lock()
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
drivers/net/geneve.c | 5 +----
net/8021q/vlan_core.c | 5 +----
net/ethernet/eth.c | 5 +----
net/ipv4/af_inet.c | 12 ++++--------
net/ipv4/fou.c | 12 +++---------
net/ipv4/gre_offload.c | 9 +++------
net/ipv4/udp_offload.c | 2 --
net/ipv6/ip6_offload.c | 6 +-----
net/ipv6/udp_offload.c | 2 --
9 files changed, 14 insertions(+), 44 deletions(-)
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 9d26d1b965d221c7eefbce47fc5e504b7f35cff6..9caff2e01d19751bbd4a05bf5e204a16dde8a779 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -517,18 +517,15 @@ static struct sk_buff *geneve_gro_receive(struct sock *sk,
type = gh->proto_type;
- rcu_read_lock();
ptype = gro_find_receive_by_type(type);
if (!ptype)
- goto out_unlock;
+ goto out;
skb_gro_pull(skb, gh_len);
skb_gro_postpull_rcsum(skb, gh, gh_len);
pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb);
flush = 0;
-out_unlock:
- rcu_read_unlock();
out:
skb_gro_flush_final(skb, pp, flush);
diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index 59bc13b5f14f6a24bef0b8916f67101ce8dc4376..534eebb5a2e6d10b8ecd893f0ed5e1dc2113f036 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -476,10 +476,9 @@ static struct sk_buff *vlan_gro_receive(struct list_head *head,
type = vhdr->h_vlan_encapsulated_proto;
- rcu_read_lock();
ptype = gro_find_receive_by_type(type);
if (!ptype)
- goto out_unlock;
+ goto out;
flush = 0;
@@ -501,8 +500,6 @@ static struct sk_buff *vlan_gro_receive(struct list_head *head,
ipv6_gro_receive, inet_gro_receive,
head, skb);
-out_unlock:
- rcu_read_unlock();
out:
skb_gro_flush_final(skb, pp, flush);
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index c7d9e08107cb437240e3e3ef1c3e564046400570..d4fa2f152efcbd7faf98ba4364e65cad8619ec1f 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -436,11 +436,10 @@ struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
type = eh->h_proto;
- rcu_read_lock();
ptype = gro_find_receive_by_type(type);
if (ptype == NULL) {
flush = 1;
- goto out_unlock;
+ goto out;
}
skb_gro_pull(skb, sizeof(*eh));
@@ -450,8 +449,6 @@ struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
ipv6_gro_receive, inet_gro_receive,
head, skb);
-out_unlock:
- rcu_read_unlock();
out:
skb_gro_flush_final(skb, pp, flush);
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index c66b0563a267546ccd045dda10fbd854a21fe5ce..7afd8c8b25e043b6cb6638b74f715ab65254da64 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1452,19 +1452,18 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
proto = iph->protocol;
- rcu_read_lock();
ops = rcu_dereference(inet_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive)
- goto out_unlock;
+ goto out;
if (*(u8 *)iph != 0x45)
- goto out_unlock;
+ goto out;
if (ip_is_fragment(iph))
- goto out_unlock;
+ goto out;
if (unlikely(ip_fast_csum((u8 *)iph, 5)))
- goto out_unlock;
+ goto out;
id = ntohl(*(__be32 *)&iph->id);
flush = (u16)((ntohl(*(__be32 *)iph) ^ skb_gro_len(skb)) | (id & ~IP_DF));
@@ -1541,9 +1540,6 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
pp = indirect_call_gro_receive(tcp4_gro_receive, udp4_gro_receive,
ops->callbacks.gro_receive, head, skb);
-out_unlock:
- rcu_read_unlock();
-
out:
skb_gro_flush_final(skb, pp, flush);
diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index b56d6b40c0a26f3b70226937779e355b504b79bd..6ebc345e6001c2b76926576acd6377ea6abeefbe 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -247,17 +247,14 @@ static struct sk_buff *fou_gro_receive(struct sock *sk,
/* Flag this frame as already having an outer encap header */
NAPI_GRO_CB(skb)->is_fou = 1;
- rcu_read_lock();
offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
ops = rcu_dereference(offloads[proto]);
if (!ops || !ops->callbacks.gro_receive)
- goto out_unlock;
+ goto out;
pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
-out_unlock:
- rcu_read_unlock();
-
+out:
return pp;
}
@@ -439,17 +436,14 @@ static struct sk_buff *gue_gro_receive(struct sock *sk,
/* Flag this frame as already having an outer encap header */
NAPI_GRO_CB(skb)->is_fou = 1;
- rcu_read_lock();
offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
ops = rcu_dereference(offloads[proto]);
if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_receive))
- goto out_unlock;
+ goto out;
pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
flush = 0;
-out_unlock:
- rcu_read_unlock();
out:
skb_gro_flush_final_remcsum(skb, pp, flush, &grc);
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index 740298dac7d32f7bef1d69214d65c665c18b649c..c6b5d327e3e14de1a0a77dbb6c53acced157bcfb 100644
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -163,10 +163,9 @@ static struct sk_buff *gre_gro_receive(struct list_head *head,
type = greh->protocol;
- rcu_read_lock();
ptype = gro_find_receive_by_type(type);
if (!ptype)
- goto out_unlock;
+ goto out;
grehlen = GRE_HEADER_SECTION;
@@ -180,13 +179,13 @@ static struct sk_buff *gre_gro_receive(struct list_head *head,
if (skb_gro_header_hard(skb, hlen)) {
greh = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!greh))
- goto out_unlock;
+ goto out;
}
/* Don't bother verifying checksum if we're going to flush anyway. */
if ((greh->flags & GRE_CSUM) && !NAPI_GRO_CB(skb)->flush) {
if (skb_gro_checksum_simple_validate(skb))
- goto out_unlock;
+ goto out;
skb_gro_checksum_try_convert(skb, IPPROTO_GRE,
null_compute_pseudo);
@@ -230,8 +229,6 @@ static struct sk_buff *gre_gro_receive(struct list_head *head,
pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb);
flush = 0;
-out_unlock:
- rcu_read_unlock();
out:
skb_gro_flush_final(skb, pp, flush);
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index cbeb8965d1b771b4d50c888a42279287904304e9..3be5c083879d98a6c100b05635d0818c328ced31 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -628,13 +628,11 @@ struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb)
inet_gro_compute_pseudo);
skip:
NAPI_GRO_CB(skb)->is_ipv6 = 0;
- rcu_read_lock();
if (static_branch_unlikely(&udp_encap_needed_key))
sk = udp4_gro_lookup_skb(skb, uh->source, uh->dest);
pp = udp_gro_receive(head, skb, uh, sk);
- rcu_read_unlock();
return pp;
flush:
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 1b9827ff8ccf48e61e233e39d671aa67c8fff0ab..67b9ba5e159c3a83207310d2d0b7a42557da895b 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -208,7 +208,6 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
flush += ntohs(iph->payload_len) != skb_gro_len(skb);
- rcu_read_lock();
proto = iph->nexthdr;
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive) {
@@ -221,7 +220,7 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
ops = rcu_dereference(inet6_offloads[proto]);
if (!ops || !ops->callbacks.gro_receive)
- goto out_unlock;
+ goto out;
iph = ipv6_hdr(skb);
}
@@ -279,9 +278,6 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
pp = indirect_call_gro_receive_l4(tcp6_gro_receive, udp6_gro_receive,
ops->callbacks.gro_receive, head, skb);
-out_unlock:
- rcu_read_unlock();
-
out:
skb_gro_flush_final(skb, pp, flush);
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 50a8a65fad2324d124bcd26eaa93b1ffb9cccc7f..7720d04ed396d0e190561e4d608cf5a7857050d8 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -145,13 +145,11 @@ struct sk_buff *udp6_gro_receive(struct list_head *head, struct sk_buff *skb)
skip:
NAPI_GRO_CB(skb)->is_ipv6 = 1;
- rcu_read_lock();
if (static_branch_unlikely(&udpv6_encap_needed_key))
sk = udp6_gro_lookup_skb(skb, uh->source, uh->dest);
pp = udp_gro_receive(head, skb, uh, sk);
- rcu_read_unlock();
return pp;
flush:
--
2.34.0.rc2.393.gf8c9666880-goog
next prev parent reply other threads:[~2021-11-23 22:56 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-23 22:56 [PATCH net-next 0/2] gro: remove redundant rcu_read_lock Eric Dumazet
2021-11-23 22:56 ` Eric Dumazet [this message]
2021-11-23 22:56 ` [PATCH net-next 2/2] gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers Eric Dumazet
2021-11-25 1:30 ` [PATCH net-next 0/2] gro: remove redundant rcu_read_lock patchwork-bot+netdevbpf
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