[PATCH net-next v2 4/4] net: indirect call helpers for ipv4/ipv6 dst_check functions

From: Brian Vazquez
Date: Fri Dec 11 2020 - 18:36:08 EST


From: brianvv <brianvv@xxxxxxxxxx>

This patch avoids the indirect call for the common case:
ip6_dst_check and ipv4_dst_check

Signed-off-by: brianvv <brianvv@xxxxxxxxxx>
---
include/net/dst.h | 7 ++++++-
net/core/sock.c | 12 ++++++++++--
net/ipv4/route.c | 7 +++++--
net/ipv4/tcp_ipv4.c | 5 ++++-
net/ipv6/route.c | 7 +++++--
net/ipv6/tcp_ipv6.c | 5 ++++-
6 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/include/net/dst.h b/include/net/dst.h
index 9f474a79ed7d..26f134ad3a25 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -459,10 +459,15 @@ static inline int dst_input(struct sk_buff *skb)
ip6_input, ip_local_deliver, skb);
}

+INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
+ u32));
+INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
+ u32));
static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
{
if (dst->obsolete)
- dst = dst->ops->check(dst, cookie);
+ dst = INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check,
+ ipv4_dst_check, dst, cookie);
return dst;
}

diff --git a/net/core/sock.c b/net/core/sock.c
index 4fd7e785f177..753b831a9d70 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -526,11 +526,17 @@ int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
}
EXPORT_SYMBOL(__sk_receive_skb);

+INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
+ u32));
+INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
+ u32));
struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
{
struct dst_entry *dst = __sk_dst_get(sk);

- if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
+ if (dst && dst->obsolete &&
+ INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
+ dst, cookie) == NULL) {
sk_tx_queue_clear(sk);
sk->sk_dst_pending_confirm = 0;
RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
@@ -546,7 +552,9 @@ struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
{
struct dst_entry *dst = sk_dst_get(sk);

- if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
+ if (dst && dst->obsolete &&
+ INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
+ dst, cookie) == NULL) {
sk_dst_reset(sk);
dst_release(dst);
return NULL;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 4fac91f8bd6c..9e6537709794 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -133,7 +133,8 @@ static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
* Interface to generic destination cache.
*/

-static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
+INDIRECT_CALLABLE_SCOPE
+struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
INDIRECT_CALLABLE_SCOPE
unsigned int ipv4_mtu(const struct dst_entry *dst);
@@ -1188,7 +1189,8 @@ void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
}
EXPORT_SYMBOL_GPL(ipv4_sk_redirect);

-static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
+INDIRECT_CALLABLE_SCOPE struct dst_entry *ipv4_dst_check(struct dst_entry *dst,
+ u32 cookie)
{
struct rtable *rt = (struct rtable *) dst;

@@ -1204,6 +1206,7 @@ static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
return NULL;
return dst;
}
+EXPORT_SYMBOL(ipv4_dst_check);

static void ipv4_send_dest_unreach(struct sk_buff *skb)
{
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index af2338294598..aba5061024c7 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1646,6 +1646,8 @@ u16 tcp_v4_get_syncookie(struct sock *sk, struct iphdr *iph,
return mss;
}

+INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
+ u32));
/* The socket must have it's spinlock held when we get
* here, unless it is a TCP_LISTEN socket.
*
@@ -1665,7 +1667,8 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
sk_mark_napi_id(sk, skb);
if (dst) {
if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
- !dst->ops->check(dst, 0)) {
+ !INDIRECT_CALL_1(dst->ops->check, ipv4_dst_check,
+ dst, 0)) {
dst_release(dst);
sk->sk_rx_dst = NULL;
}
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 22caee290b6c..e074fb5964e2 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -81,7 +81,8 @@ enum rt6_nud_state {
RT6_NUD_SUCCEED = 1
};

-static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
+INDIRECT_CALLABLE_SCOPE
+struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
static unsigned int ip6_default_advmss(const struct dst_entry *dst);
INDIRECT_CALLABLE_SCOPE
unsigned int ip6_mtu(const struct dst_entry *dst);
@@ -2612,7 +2613,8 @@ static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
return NULL;
}

-static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
+INDIRECT_CALLABLE_SCOPE struct dst_entry *ip6_dst_check(struct dst_entry *dst,
+ u32 cookie)
{
struct dst_entry *dst_ret;
struct fib6_info *from;
@@ -2642,6 +2644,7 @@ static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)

return dst_ret;
}
+EXPORT_SYMBOL(ip6_dst_check);

static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
{
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 1a1510513739..9e61e4fda03e 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1417,6 +1417,8 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *
return NULL;
}

+INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
+ u32));
/* The socket must have it's spinlock held when we get
* here, unless it is a TCP_LISTEN socket.
*
@@ -1470,7 +1472,8 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
sk_mark_napi_id(sk, skb);
if (dst) {
if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
- dst->ops->check(dst, np->rx_dst_cookie) == NULL) {
+ INDIRECT_CALL_1(dst->ops->check, ip6_dst_check,
+ dst, np->rx_dst_cookie) == NULL) {
dst_release(dst);
sk->sk_rx_dst = NULL;
}
--
2.29.2.576.ga3fc446d84-goog