net: gro: skb_gro_header helper function

Introduce a simple helper function to replace a common pattern.
When accessing the GRO header, we fetch the pointer from frag0,
then test its validity and fetch it from the skb when necessary.

This leads to the pattern
skb_gro_header_fast -> skb_gro_header_hard -> skb_gro_header_slow
recurring many times throughout GRO code.

This patch replaces these patterns with a single inlined function
call, improving code readability.

Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220823071034.GA56142@debian
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Richard Gobert 2022-08-23 09:10:49 +02:00 committed by Paolo Abeni
parent 77a70f9c5b
commit 35ffb66547
10 changed files with 45 additions and 69 deletions

View File

@ -503,12 +503,9 @@ static struct sk_buff *geneve_gro_receive(struct sock *sk,
off_gnv = skb_gro_offset(skb);
hlen = off_gnv + sizeof(*gh);
gh = skb_gro_header_fast(skb, off_gnv);
if (skb_gro_header_hard(skb, hlen)) {
gh = skb_gro_header_slow(skb, hlen, off_gnv);
if (unlikely(!gh))
goto out;
}
gh = skb_gro_header(skb, hlen, off_gnv);
if (unlikely(!gh))
goto out;
if (gh->ver != GENEVE_VER || gh->oam)
goto out;

View File

@ -713,12 +713,9 @@ static struct sk_buff *vxlan_gro_receive(struct sock *sk,
off_vx = skb_gro_offset(skb);
hlen = off_vx + sizeof(*vh);
vh = skb_gro_header_fast(skb, off_vx);
if (skb_gro_header_hard(skb, hlen)) {
vh = skb_gro_header_slow(skb, hlen, off_vx);
if (unlikely(!vh))
goto out;
}
vh = skb_gro_header(skb, hlen, off_vx);
if (unlikely(!vh))
goto out;
skb_gro_postpull_rcsum(skb, vh, sizeof(struct vxlanhdr));

View File

@ -160,6 +160,17 @@ static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,
return skb->data + offset;
}
static inline void *skb_gro_header(struct sk_buff *skb,
unsigned int hlen, unsigned int offset)
{
void *ptr;
ptr = skb_gro_header_fast(skb, offset);
if (skb_gro_header_hard(skb, hlen))
ptr = skb_gro_header_slow(skb, hlen, offset);
return ptr;
}
static inline void *skb_gro_network_header(struct sk_buff *skb)
{
return (NAPI_GRO_CB(skb)->frag0 ?: skb->data) +
@ -301,12 +312,9 @@ static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,
return ptr;
}
ptr = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, off + plen)) {
ptr = skb_gro_header_slow(skb, off + plen, off);
if (!ptr)
return NULL;
}
ptr = skb_gro_header(skb, off + plen, off);
if (!ptr)
return NULL;
delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,
start, offset);
@ -329,12 +337,9 @@ static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
if (!grc->delta)
return;
ptr = skb_gro_header_fast(skb, grc->offset);
if (skb_gro_header_hard(skb, grc->offset + sizeof(u16))) {
ptr = skb_gro_header_slow(skb, plen, grc->offset);
if (!ptr)
return;
}
ptr = skb_gro_header(skb, plen, grc->offset);
if (!ptr)
return;
remcsum_unadjust((__sum16 *)ptr, grc->delta);
}
@ -405,9 +410,7 @@ static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
off = skb_gro_offset(skb);
hlen = off + sizeof(*uh);
uh = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen))
uh = skb_gro_header_slow(skb, hlen, off);
uh = skb_gro_header(skb, hlen, off);
return uh;
}

View File

@ -467,12 +467,9 @@ static struct sk_buff *vlan_gro_receive(struct list_head *head,
off_vlan = skb_gro_offset(skb);
hlen = off_vlan + sizeof(*vhdr);
vhdr = skb_gro_header_fast(skb, off_vlan);
if (skb_gro_header_hard(skb, hlen)) {
vhdr = skb_gro_header_slow(skb, hlen, off_vlan);
if (unlikely(!vhdr))
goto out;
}
vhdr = skb_gro_header(skb, hlen, off_vlan);
if (unlikely(!vhdr))
goto out;
type = vhdr->h_vlan_encapsulated_proto;

View File

@ -414,12 +414,9 @@ struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
off_eth = skb_gro_offset(skb);
hlen = off_eth + sizeof(*eh);
eh = skb_gro_header_fast(skb, off_eth);
if (skb_gro_header_hard(skb, hlen)) {
eh = skb_gro_header_slow(skb, hlen, off_eth);
if (unlikely(!eh))
goto out;
}
eh = skb_gro_header(skb, hlen, off_eth);
if (unlikely(!eh))
goto out;
flush = 0;

View File

@ -1464,12 +1464,9 @@ struct sk_buff *inet_gro_receive(struct list_head *head, struct sk_buff *skb)
off = skb_gro_offset(skb);
hlen = off + sizeof(*iph);
iph = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen)) {
iph = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!iph))
goto out;
}
iph = skb_gro_header(skb, hlen, off);
if (unlikely(!iph))
goto out;
proto = iph->protocol;

View File

@ -323,12 +323,9 @@ static struct sk_buff *gue_gro_receive(struct sock *sk,
off = skb_gro_offset(skb);
len = off + sizeof(*guehdr);
guehdr = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, len)) {
guehdr = skb_gro_header_slow(skb, len, off);
if (unlikely(!guehdr))
goto out;
}
guehdr = skb_gro_header(skb, len, off);
if (unlikely(!guehdr))
goto out;
switch (guehdr->version) {
case 0:

View File

@ -137,12 +137,9 @@ static struct sk_buff *gre_gro_receive(struct list_head *head,
off = skb_gro_offset(skb);
hlen = off + sizeof(*greh);
greh = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen)) {
greh = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!greh))
goto out;
}
greh = skb_gro_header(skb, hlen, off);
if (unlikely(!greh))
goto out;
/* Only support version 0 and K (key), C (csum) flags. Note that
* although the support for the S (seq#) flag can be added easily

View File

@ -195,12 +195,9 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb)
off = skb_gro_offset(skb);
hlen = off + sizeof(*th);
th = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen)) {
th = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!th))
goto out;
}
th = skb_gro_header(skb, hlen, off);
if (unlikely(!th))
goto out;
thlen = th->doff * 4;
if (thlen < sizeof(*th))

View File

@ -219,12 +219,9 @@ INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
off = skb_gro_offset(skb);
hlen = off + sizeof(*iph);
iph = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen)) {
iph = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!iph))
goto out;
}
iph = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!iph))
goto out;
skb_set_network_header(skb, off);
skb_gro_pull(skb, sizeof(*iph));