@@ -667,6 +667,7 @@ enum sock_flags {
* user-space instead.
*/
SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
+ SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
};
static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
@@ -74,4 +74,6 @@
#define SO_LOCK_FILTER 44
+#define SO_SELECT_ERR_QUEUE 45
+
#endif /* __ASM_GENERIC_SOCKET_H */
@@ -748,8 +748,11 @@ unsigned int 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(&sk->sk_error_queue)) {
mask |= POLLERR;
+ if (sock_flag(sk, SOCK_SELECT_ERR_QUEUE))
+ mask |= POLLPRI;
+ }
if (sk->sk_shutdown & RCV_SHUTDOWN)
mask |= POLLRDHUP | POLLIN | POLLRDNORM;
if (sk->sk_shutdown == SHUTDOWN_MASK)
@@ -907,6 +907,10 @@ set_rcvbuf:
sock_valbool_flag(sk, SOCK_NOFCS, valbool);
break;
+ case SO_SELECT_ERR_QUEUE:
+ sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
+ break;
+
default:
ret = -ENOPROTOOPT;
break;
@@ -1160,6 +1164,10 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
break;
+ case SO_SELECT_ERR_QUEUE:
+ v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
+ break;
+
default:
return -ENOPROTOOPT;
}
@@ -2196,8 +2196,11 @@ static unsigned int 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(&sk->sk_error_queue)) {
mask |= POLLERR;
+ if (sock_flag(sk, SOCK_SELECT_ERR_QUEUE))
+ mask |= POLLPRI;
+ }
if (sk->sk_shutdown & RCV_SHUTDOWN)
mask |= POLLRDHUP | POLLIN | POLLRDNORM;
if (sk->sk_shutdown == SHUTDOWN_MASK)
Currently, when a socket receives something on the error queue it only wakes up the socket on select if it is in the "read" list, that is the socket has something to read. It is useful also to wake the socket if it is in the error list, which would enable software to wait on error queue packets without waking up for regular data on the socket. The main use case is for receiving timestamped transmit packets which return the timestamp to the socket via the error queue. This enables an application to select on the socket for the error queue only instead of for the regular traffic. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Cc: Jeffrey Kirsher <jeffrey.t.kirsher@intel.com> Cc: Richard Cochran <richardcochran@gmail.com> --- include/net/sock.h | 1 + include/uapi/asm-generic/socket.h | 2 ++ net/core/datagram.c | 5 ++++- net/core/sock.c | 8 ++++++++ net/unix/af_unix.c | 5 ++++- 5 files changed, 19 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html