For a function that needs to be called with the socket spinlock held, sleeping would seem to be a bad idea. This function does in fact avoid sleeping when calling kernel_sendpage_locked on the page part of the skb. However, it doesn't do that when sending the linear part. Resulting in sleeping when the socket send buffer is full.
This patch fixes it by setting the MSG_DONTWAIT flag when calling kernel_sendmsg_locked. Signed-off-by: Herbert Xu <herb...@gondor.apana.org.au> --- net/core/skbuff.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 6b0ff39..8197b7a 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2279,6 +2279,7 @@ int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset, kv.iov_base = skb->data + offset; kv.iov_len = slen; memset(&msg, 0, sizeof(msg)); + msg.msg_flags = MSG_DONTWAIT; ret = kernel_sendmsg_locked(sk, &msg, &kv, 1, slen); if (ret <= 0)