Currently, the sunrpc server is refusing to allow us to process new RPC
calls if the TCP send buffer is 2/3 full, even if we do actually have
enough free space to guarantee that we can send another request.
The following patch fixes svc_tcp_has_wspace() so that we only stop
processing requests if we know that the socket buffer cannot possibly fit
another reply.
It also fixes the tcp write_space() callback so that we only clear the
SOCK_NOSPACE flag when the TCP send buffer is less than 2/3 full.
This should ensure that the send window will grow as per the standard TCP
socket code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx>
---
net/sunrpc/svcsock.c | 36 +++++++++++++++++++-----------------
1 files changed, 19 insertions(+), 17 deletions(-)
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index af31988..eed978e 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -345,6 +345,7 @@ static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
lock_sock(sock->sk);
sock->sk->sk_sndbuf = snd * 2;
sock->sk->sk_rcvbuf = rcv * 2;
+ sock->sk->sk_write_space(sock->sk);
release_sock(sock->sk);
#endif
}
@@ -386,6 +387,15 @@ static void svc_write_space(struct sock *sk)
}
}
+static void svc_tcp_write_space(struct sock *sk)
+{
+ struct socket *sock = sk->sk_socket;
+
+ if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sock)
+ clear_bit(SOCK_NOSPACE, &sock->flags);
+ svc_write_space(sk);
+}
+
/*
* Copy the UDP datagram's destination address to the rqstp structure.
* The 'destination' address in this case is the address to which the
@@ -617,6 +627,7 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv)
* receive and respond to one request.
* svc_udp_recvfrom will re-adjust if necessary
*/
+ svsk->sk_sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
svc_sock_setbufsize(svsk->sk_sock,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
@@ -962,25 +973,16 @@ static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp)
static int svc_tcp_has_wspace(struct svc_xprt *xprt)
{
struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt);
- struct svc_serv *serv = svsk->sk_xprt.xpt_server;
+ struct svc_serv *serv = svsk->sk_xprt.xpt_server;
int required;
- int wspace;
- /*
- * Set the SOCK_NOSPACE flag before checking the available
- * sock space.
- */
+ if (test_bit(XPT_LISTENER, &xprt->xpt_flags))
+ return 1;
+ required = atomic_read(&xprt->xpt_reserved) + serv->sv_max_mesg;
+ if (sk_stream_wspace(svsk->sk_sk) >= required)
+ return 1;
set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
- required = atomic_read(&svsk->sk_xprt.xpt_reserved) + serv->sv_max_mesg;
- wspace = sk_stream_wspace(svsk->sk_sk);
-
- if (wspace < sk_stream_min_wspace(svsk->sk_sk))
- return 0;
- if (required * 2 > wspace)
- return 0;
-
- clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags);
- return 1;
+ return 0;
}
static struct svc_xprt *svc_tcp_create(struct svc_serv *serv,
@@ -1036,7 +1038,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
dprintk("setting up TCP socket for reading\n");
sk->sk_state_change = svc_tcp_state_change;
sk->sk_data_ready = svc_tcp_data_ready;
- sk->sk_write_space = svc_write_space;
+ sk->sk_write_space = svc_tcp_write_space;
svsk->sk_reclen = 0;
svsk->sk_tcplen = 0;
--
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