summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--drivers/crypto/chelsio/chtls/chtls_io.c2
-rw-r--r--drivers/isdn/capi/capi.c2
-rw-r--r--drivers/nvme/host/tcp.c2
-rw-r--r--include/linux/skbuff.h33
-rw-r--r--net/atm/common.c2
-rw-r--r--net/bluetooth/af_bluetooth.c4
-rw-r--r--net/caif/caif_socket.c2
-rw-r--r--net/core/datagram.c8
-rw-r--r--net/core/sock.c2
-rw-r--r--net/decnet/af_decnet.c2
-rw-r--r--net/ipv4/tcp.c4
-rw-r--r--net/ipv4/udp.c8
-rw-r--r--net/nfc/llcp_sock.c4
-rw-r--r--net/phonet/socket.c4
-rw-r--r--net/sctp/socket.c6
-rw-r--r--net/tipc/socket.c4
-rw-r--r--net/unix/af_unix.c6
-rw-r--r--net/vmw_vsock/af_vsock.c2
18 files changed, 56 insertions, 41 deletions
diff --git a/drivers/crypto/chelsio/chtls/chtls_io.c b/drivers/crypto/chelsio/chtls/chtls_io.c
index 0891ab829b1b..98bc5a4cd5e7 100644
--- a/drivers/crypto/chelsio/chtls/chtls_io.c
+++ b/drivers/crypto/chelsio/chtls/chtls_io.c
@@ -1702,7 +1702,7 @@ int chtls_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
return peekmsg(sk, msg, len, nonblock, flags);
if (sk_can_busy_loop(sk) &&
- skb_queue_empty(&sk->sk_receive_queue) &&
+ skb_queue_empty_lockless(&sk->sk_receive_queue) &&
sk->sk_state == TCP_ESTABLISHED)
sk_busy_loop(sk, nonblock);
diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c
index c92b405b7646..ba8619524231 100644
--- a/drivers/isdn/capi/capi.c
+++ b/drivers/isdn/capi/capi.c
@@ -744,7 +744,7 @@ capi_poll(struct file *file, poll_table *wait)
poll_wait(file, &(cdev->recvwait), wait);
mask = EPOLLOUT | EPOLLWRNORM;
- if (!skb_queue_empty(&cdev->recvqueue))
+ if (!skb_queue_empty_lockless(&cdev->recvqueue))
mask |= EPOLLIN | EPOLLRDNORM;
return mask;
}
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 770dbcbc999e..7544be84ab35 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -2219,7 +2219,7 @@ static int nvme_tcp_poll(struct blk_mq_hw_ctx *hctx)
struct nvme_tcp_queue *queue = hctx->driver_data;
struct sock *sk = queue->sock->sk;
- if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue))
+ if (sk_can_busy_loop(sk) && skb_queue_empty_lockless(&sk->sk_receive_queue))
sk_busy_loop(sk, true);
nvme_tcp_try_recv(queue);
return queue->nr_cqe;
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index a391147c03d4..64a395c7f689 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1496,6 +1496,19 @@ static inline int skb_queue_empty(const struct sk_buff_head *list)
}
/**
+ * skb_queue_empty_lockless - check if a queue is empty
+ * @list: queue head
+ *
+ * Returns true if the queue is empty, false otherwise.
+ * This variant can be used in lockless contexts.
+ */
+static inline bool skb_queue_empty_lockless(const struct sk_buff_head *list)
+{
+ return READ_ONCE(list->next) == (const struct sk_buff *) list;
+}
+
+
+/**
* skb_queue_is_last - check if skb is the last entry in the queue
* @list: queue head
* @skb: buffer
@@ -1848,9 +1861,11 @@ static inline void __skb_insert(struct sk_buff *newsk,
struct sk_buff *prev, struct sk_buff *next,
struct sk_buff_head *list)
{
- newsk->next = next;
- newsk->prev = prev;
- next->prev = prev->next = newsk;
+ /* see skb_queue_empty_lockless() for the opposite READ_ONCE() */
+ WRITE_ONCE(newsk->next, next);
+ WRITE_ONCE(newsk->prev, prev);
+ WRITE_ONCE(next->prev, newsk);
+ WRITE_ONCE(prev->next, newsk);
list->qlen++;
}
@@ -1861,11 +1876,11 @@ static inline void __skb_queue_splice(const struct sk_buff_head *list,
struct sk_buff *first = list->next;
struct sk_buff *last = list->prev;
- first->prev = prev;
- prev->next = first;
+ WRITE_ONCE(first->prev, prev);
+ WRITE_ONCE(prev->next, first);
- last->next = next;
- next->prev = last;
+ WRITE_ONCE(last->next, next);
+ WRITE_ONCE(next->prev, last);
}
/**
@@ -2006,8 +2021,8 @@ static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
next = skb->next;
prev = skb->prev;
skb->next = skb->prev = NULL;
- next->prev = prev;
- prev->next = next;
+ WRITE_ONCE(next->prev, prev);
+ WRITE_ONCE(prev->next, next);
}
/**
diff --git a/net/atm/common.c b/net/atm/common.c
index b7528e77997c..0ce530af534d 100644
--- a/net/atm/common.c
+++ b/net/atm/common.c
@@ -668,7 +668,7 @@ __poll_t vcc_poll(struct file *file, struct socket *sock, poll_table *wait)
mask |= EPOLLHUP;
/* readable? */
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
/* writable? */
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 94ddf19998c7..5f508c50649d 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -460,7 +460,7 @@ __poll_t bt_sock_poll(struct file *file, struct socket *sock,
if (sk->sk_state == BT_LISTEN)
return bt_accept_poll(sk);
- if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
+ if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR |
(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
@@ -470,7 +470,7 @@ __poll_t bt_sock_poll(struct file *file, struct socket *sock,
if (sk->sk_shutdown == SHUTDOWN_MASK)
mask |= EPOLLHUP;
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
if (sk->sk_state == BT_CLOSED)
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index 13ea920600ae..ef14da50a981 100644
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -953,7 +953,7 @@ static __poll_t caif_poll(struct file *file,
mask |= EPOLLRDHUP;
/* readable? */
- if (!skb_queue_empty(&sk->sk_receive_queue) ||
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
(sk->sk_shutdown & RCV_SHUTDOWN))
mask |= EPOLLIN | EPOLLRDNORM;
diff --git a/net/core/datagram.c b/net/core/datagram.c
index c210fc116103..da3c24ed129c 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -97,7 +97,7 @@ int __skb_wait_for_more_packets(struct sock *sk, int *err, long *timeo_p,
if (error)
goto out_err;
- if (sk->sk_receive_queue.prev != skb)
+ if (READ_ONCE(sk->sk_receive_queue.prev) != skb)
goto out;
/* Socket shut down? */
@@ -278,7 +278,7 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags,
break;
sk_busy_loop(sk, flags & MSG_DONTWAIT);
- } while (sk->sk_receive_queue.prev != *last);
+ } while (READ_ONCE(sk->sk_receive_queue.prev) != *last);
error = -EAGAIN;
@@ -767,7 +767,7 @@ __poll_t datagram_poll(struct file *file, struct socket *sock,
mask = 0;
/* exceptional events? */
- if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
+ if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR |
(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
@@ -777,7 +777,7 @@ __poll_t datagram_poll(struct file *file, struct socket *sock,
mask |= EPOLLHUP;
/* readable? */
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
/* Connection-based need to check for termination and startup */
diff --git a/net/core/sock.c b/net/core/sock.c
index a515392ba84b..b8e758bcb6ad 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -3600,7 +3600,7 @@ bool sk_busy_loop_end(void *p, unsigned long start_time)
{
struct sock *sk = p;
- return !skb_queue_empty(&sk->sk_receive_queue) ||
+ return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
sk_busy_loop_timeout(sk, start_time);
}
EXPORT_SYMBOL(sk_busy_loop_end);
diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index 0ea75286abf4..3349ea81f901 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -1205,7 +1205,7 @@ static __poll_t dn_poll(struct file *file, struct socket *sock, poll_table *wai
struct dn_scp *scp = DN_SK(sk);
__poll_t mask = datagram_poll(file, sock, wait);
- if (!skb_queue_empty(&scp->other_receive_queue))
+ if (!skb_queue_empty_lockless(&scp->other_receive_queue))
mask |= EPOLLRDBAND;
return mask;
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 42187a3b82f4..d8876f0e9672 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -584,7 +584,7 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
}
/* This barrier is coupled with smp_wmb() in tcp_reset() */
smp_rmb();
- if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
+ if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR;
return mask;
@@ -1964,7 +1964,7 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
if (unlikely(flags & MSG_ERRQUEUE))
return inet_recv_error(sk, msg, len, addr_len);
- if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue) &&
+ if (sk_can_busy_loop(sk) && skb_queue_empty_lockless(&sk->sk_receive_queue) &&
(sk->sk_state == TCP_ESTABLISHED))
sk_busy_loop(sk, nonblock);
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 14bc654b6842..345a3d43f5a6 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1577,7 +1577,7 @@ static int first_packet_length(struct sock *sk)
spin_lock_bh(&rcvq->lock);
skb = __first_packet_length(sk, rcvq, &total);
- if (!skb && !skb_queue_empty(sk_queue)) {
+ if (!skb && !skb_queue_empty_lockless(sk_queue)) {
spin_lock(&sk_queue->lock);
skb_queue_splice_tail_init(sk_queue, rcvq);
spin_unlock(&sk_queue->lock);
@@ -1650,7 +1650,7 @@ struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
return skb;
}
- if (skb_queue_empty(sk_queue)) {
+ if (skb_queue_empty_lockless(sk_queue)) {
spin_unlock_bh(&queue->lock);
goto busy_check;
}
@@ -1676,7 +1676,7 @@ busy_check:
break;
sk_busy_loop(sk, flags & MSG_DONTWAIT);
- } while (!skb_queue_empty(sk_queue));
+ } while (!skb_queue_empty_lockless(sk_queue));
/* sk_queue is empty, reader_queue may contain peeked packets */
} while (timeo &&
@@ -2712,7 +2712,7 @@ __poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait)
__poll_t mask = datagram_poll(file, sock, wait);
struct sock *sk = sock->sk;
- if (!skb_queue_empty(&udp_sk(sk)->reader_queue))
+ if (!skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
mask |= EPOLLIN | EPOLLRDNORM;
/* Check for false positives due to checksum errors */
diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c
index ccdd790e163a..28604414dec1 100644
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -554,11 +554,11 @@ static __poll_t llcp_sock_poll(struct file *file, struct socket *sock,
if (sk->sk_state == LLCP_LISTEN)
return llcp_accept_poll(sk);
- if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
+ if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR |
(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
if (sk->sk_state == LLCP_CLOSED)
diff --git a/net/phonet/socket.c b/net/phonet/socket.c
index 96ea9f254ae9..76d499f6af9a 100644
--- a/net/phonet/socket.c
+++ b/net/phonet/socket.c
@@ -338,9 +338,9 @@ static __poll_t pn_socket_poll(struct file *file, struct socket *sock,
if (sk->sk_state == TCP_CLOSE)
return EPOLLERR;
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
- if (!skb_queue_empty(&pn->ctrlreq_queue))
+ if (!skb_queue_empty_lockless(&pn->ctrlreq_queue))
mask |= EPOLLPRI;
if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
return EPOLLHUP;
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 5ca0ec0e823c..ca81e06df165 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -8476,7 +8476,7 @@ __poll_t sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
mask = 0;
/* Is there any exceptional events? */
- if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
+ if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR |
(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
if (sk->sk_shutdown & RCV_SHUTDOWN)
@@ -8485,7 +8485,7 @@ __poll_t sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
mask |= EPOLLHUP;
/* Is it readable? Reconsider this code with TCP-style support. */
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
/* The association is either gone or not ready. */
@@ -8871,7 +8871,7 @@ struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
if (sk_can_busy_loop(sk)) {
sk_busy_loop(sk, noblock);
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
continue;
}
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index f8bbc4aab213..4b92b196cfa6 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -740,7 +740,7 @@ static __poll_t tipc_poll(struct file *file, struct socket *sock,
/* fall through */
case TIPC_LISTEN:
case TIPC_CONNECTING:
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
revents |= EPOLLIN | EPOLLRDNORM;
break;
case TIPC_OPEN:
@@ -748,7 +748,7 @@ static __poll_t tipc_poll(struct file *file, struct socket *sock,
revents |= EPOLLOUT;
if (!tipc_sk_type_connectionless(sk))
break;
- if (skb_queue_empty(&sk->sk_receive_queue))
+ if (skb_queue_empty_lockless(&sk->sk_receive_queue))
break;
revents |= EPOLLIN | EPOLLRDNORM;
break;
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 67e87db5877f..0d8da809bea2 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -2599,7 +2599,7 @@ static __poll_t unix_poll(struct file *file, struct socket *sock, poll_table *wa
mask |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
/* readable? */
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
/* Connection-based need to check for termination and startup */
@@ -2628,7 +2628,7 @@ static __poll_t unix_dgram_poll(struct file *file, struct socket *sock,
mask = 0;
/* exceptional events? */
- if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
+ if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR |
(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
@@ -2638,7 +2638,7 @@ static __poll_t unix_dgram_poll(struct file *file, struct socket *sock,
mask |= EPOLLHUP;
/* readable? */
- if (!skb_queue_empty(&sk->sk_receive_queue))
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
/* Connection-based need to check for termination and startup */
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 2ab43b2bba31..582a3e4dfce2 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -870,7 +870,7 @@ static __poll_t vsock_poll(struct file *file, struct socket *sock,
* the queue and write as long as the socket isn't shutdown for
* sending.
*/
- if (!skb_queue_empty(&sk->sk_receive_queue) ||
+ if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
(sk->sk_shutdown & RCV_SHUTDOWN)) {
mask |= EPOLLIN | EPOLLRDNORM;
}