From: Jason Baron jbaron@akamai.com
[ Upstream commit 4651d1802f7063e4d8c0bcad957f46ece0c04024 ]
Currently, we are only explicitly setting SOCK_NOSPACE on a write timeout for non-blocking sockets. Epoll() edge-trigger mode relies on SOCK_NOSPACE being set when -EAGAIN is returned to ensure that EPOLLOUT is raised. Expand the setting of SOCK_NOSPACE to non-blocking sockets as well that can use SO_SNDTIMEO to adjust their write timeout. This mirrors the behavior that Eric Dumazet introduced for tcp sockets.
Signed-off-by: Jason Baron jbaron@akamai.com Cc: Eric Dumazet edumazet@google.com Cc: Ursula Braun ubraun@linux.ibm.com Cc: Karsten Graul kgraul@linux.ibm.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/smc/smc_tx.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)
--- a/net/smc/smc_tx.c +++ b/net/smc/smc_tx.c @@ -70,13 +70,11 @@ static int smc_tx_wait_memory(struct smc DEFINE_WAIT_FUNC(wait, woken_wake_function); struct smc_connection *conn = &smc->conn; struct sock *sk = &smc->sk; - bool noblock; long timeo; int rc = 0;
/* similar to sk_stream_wait_memory */ timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); - noblock = timeo ? false : true; add_wait_queue(sk_sleep(sk), &wait); while (1) { sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); @@ -91,8 +89,8 @@ static int smc_tx_wait_memory(struct smc break; } if (!timeo) { - if (noblock) - set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + /* ensure EPOLLOUT is subsequently generated */ + set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); rc = -EAGAIN; break; }