From: Paolo Abeni <pabeni@redhat.com>
Date: Fri, 28 Feb 2020 14:45:22 +0100
Subject: net: datagram: drop 'destructor' argument from several helpers
Patch-mainline: v5.7-rc1
Git-commit: e427cad6eee47e2daf207cd7a4156ae72496ee07
References: bsc#1176447
The only users for such argument are the UDP protocol and the UNIX
socket family. We can safely reclaim the accounted memory directly
from the UDP code and, after the previous patch, we can do scm
stats accounting outside the datagram helpers.
Overall this cleans up a bit some datagram-related helpers, and
avoids an indirect call per packet in the UDP receive path.
v1 -> v2:
- call scm_stat_del() only when not peeking - Kirill
- fix build issue with CONFIG_INET_ESPINTCP
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/linux/skbuff.h | 12 ++----------
net/core/datagram.c | 25 +++++++------------------
net/ipv4/udp.c | 14 ++++++++------
net/unix/af_unix.c | 7 +++++--
net/xfrm/espintcp.c | 2 +-
5 files changed, 23 insertions(+), 37 deletions(-)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3486,23 +3486,15 @@ int __skb_wait_for_more_packets(struct s
struct sk_buff *__skb_try_recv_from_queue(struct sock *sk,
struct sk_buff_head *queue,
unsigned int flags,
- void (*destructor)(struct sock *sk,
- struct sk_buff *skb),
int *off, int *err,
struct sk_buff **last);
struct sk_buff *__skb_try_recv_datagram(struct sock *sk,
struct sk_buff_head *queue,
- unsigned int flags,
- void (*destructor)(struct sock *sk,
- struct sk_buff *skb),
- int *off, int *err,
+ unsigned int flags, int *off, int *err,
struct sk_buff **last);
struct sk_buff *__skb_recv_datagram(struct sock *sk,
struct sk_buff_head *sk_queue,
- unsigned int flags,
- void (*destructor)(struct sock *sk,
- struct sk_buff *skb),
- int *off, int *err);
+ unsigned int flags, int *off, int *err);
struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock,
int *err);
__poll_t datagram_poll(struct file *file, struct socket *sock,
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -166,8 +166,6 @@ done:
struct sk_buff *__skb_try_recv_from_queue(struct sock *sk,
struct sk_buff_head *queue,
unsigned int flags,
- void (*destructor)(struct sock *sk,
- struct sk_buff *skb),
int *off, int *err,
struct sk_buff **last)
{
@@ -198,8 +196,6 @@ struct sk_buff *__skb_try_recv_from_queu
refcount_inc(&skb->users);
} else {
__skb_unlink(skb, queue);
- if (destructor)
- destructor(sk, skb);
}
*off = _off;
return skb;
@@ -212,7 +208,6 @@ struct sk_buff *__skb_try_recv_from_queu
* @sk: socket
* @queue: socket queue from which to receive
* @flags: MSG\_ flags
- * @destructor: invoked under the receive lock on successful dequeue
* @off: an offset in bytes to peek skb from. Returns an offset
* within an skb where data actually starts
* @err: error code returned
@@ -245,10 +240,7 @@ struct sk_buff *__skb_try_recv_from_queu
*/
struct sk_buff *__skb_try_recv_datagram(struct sock *sk,
struct sk_buff_head *queue,
- unsigned int flags,
- void (*destructor)(struct sock *sk,
- struct sk_buff *skb),
- int *off, int *err,
+ unsigned int flags, int *off, int *err,
struct sk_buff **last)
{
struct sk_buff *skb;
@@ -269,8 +261,8 @@ struct sk_buff *__skb_try_recv_datagram(
* However, this function was correct in any case. 8)
*/
spin_lock_irqsave(&queue->lock, cpu_flags);
- skb = __skb_try_recv_from_queue(sk, queue, flags, destructor,
- off, &error, last);
+ skb = __skb_try_recv_from_queue(sk, queue, flags, off, &error,
+ last);
spin_unlock_irqrestore(&queue->lock, cpu_flags);
if (error)
goto no_packet;
@@ -293,10 +285,7 @@ EXPORT_SYMBOL(__skb_try_recv_datagram);
struct sk_buff *__skb_recv_datagram(struct sock *sk,
struct sk_buff_head *sk_queue,
- unsigned int flags,
- void (*destructor)(struct sock *sk,
- struct sk_buff *skb),
- int *off, int *err)
+ unsigned int flags, int *off, int *err)
{
struct sk_buff *skb, *last;
long timeo;
@@ -304,8 +293,8 @@ struct sk_buff *__skb_recv_datagram(stru
timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
do {
- skb = __skb_try_recv_datagram(sk, sk_queue, flags, destructor,
- off, err, &last);
+ skb = __skb_try_recv_datagram(sk, sk_queue, flags, off, err,
+ &last);
if (skb)
return skb;
@@ -326,7 +315,7 @@ struct sk_buff *skb_recv_datagram(struct
return __skb_recv_datagram(sk, &sk->sk_receive_queue,
flags | (noblock ? MSG_DONTWAIT : 0),
- NULL, &off, err);
+ &off, err);
}
EXPORT_SYMBOL(skb_recv_datagram);
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1671,10 +1671,11 @@ struct sk_buff *__skb_recv_udp(struct so
error = -EAGAIN;
do {
spin_lock_bh(&queue->lock);
- skb = __skb_try_recv_from_queue(sk, queue, flags,
- udp_skb_destructor,
- off, err, &last);
+ skb = __skb_try_recv_from_queue(sk, queue, flags, off,
+ err, &last);
if (skb) {
+ if (!(flags & MSG_PEEK))
+ udp_skb_destructor(sk, skb);
spin_unlock_bh(&queue->lock);
return skb;
}
@@ -1692,9 +1693,10 @@ struct sk_buff *__skb_recv_udp(struct so
spin_lock(&sk_queue->lock);
skb_queue_splice_tail_init(sk_queue, queue);
- skb = __skb_try_recv_from_queue(sk, queue, flags,
- udp_skb_dtor_locked,
- off, err, &last);
+ skb = __skb_try_recv_from_queue(sk, queue, flags, off,
+ err, &last);
+ if (skb && !(flags & MSG_PEEK))
+ udp_skb_dtor_locked(sk, skb);
spin_unlock(&sk_queue->lock);
spin_unlock_bh(&queue->lock);
if (skb)
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -2106,9 +2106,12 @@ static int unix_dgram_recvmsg(struct soc
skip = sk_peek_offset(sk, flags);
skb = __skb_try_recv_datagram(sk, &sk->sk_receive_queue, flags,
- scm_stat_del, &skip, &err, &last);
- if (skb)
+ &skip, &err, &last);
+ if (skb) {
+ if (!(flags & MSG_PEEK))
+ scm_stat_del(sk, skb);
break;
+ }
mutex_unlock(&u->iolock);
--- a/net/xfrm/espintcp.c
+++ b/net/xfrm/espintcp.c
@@ -100,7 +100,7 @@ static int espintcp_recvmsg(struct sock
flags |= nonblock ? MSG_DONTWAIT : 0;
- skb = __skb_recv_datagram(sk, &ctx->ike_queue, flags, NULL, &off, &err);
+ skb = __skb_recv_datagram(sk, &ctx->ike_queue, flags, &off, &err);
if (!skb)
return err;