SUNRPC: Optimise away svc_recv_available
We really do not want to do ioctls in the server's fast path. Instead, let's
use the fact that we managed to read a full record as the indicator that
we should try to read the socket again.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index c24a8ff..0e8b667 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -312,19 +312,6 @@
}
/*
- * Check input queue length
- */
-static int svc_recv_available(struct svc_sock *svsk)
-{
- struct socket *sock = svsk->sk_sock;
- int avail, err;
-
- err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail);
-
- return (err >= 0)? avail : err;
-}
-
-/*
* Generic recvfrom routine.
*/
static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
@@ -339,8 +326,14 @@
rqstp->rq_xprt_hlen = 0;
+ clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
msg.msg_flags);
+ /* If we read a full record, then assume there may be more
+ * data to read (stream based sockets only!)
+ */
+ if (len == buflen)
+ set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n",
svsk, iov[0].iov_base, iov[0].iov_len, len);
@@ -980,8 +973,6 @@
unsigned int want;
int len;
- clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
-
if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
struct kvec iov;
@@ -1073,8 +1064,6 @@
static void svc_tcp_fragment_received(struct svc_sock *svsk)
{
/* If we have more data, signal svc_xprt_enqueue() to try again */
- if (svc_recv_available(svsk) > sizeof(rpc_fraghdr))
- set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
dprintk("svc: TCP %s record (%d bytes)\n",
svc_sock_final_rec(svsk) ? "final" : "nonfinal",
svc_sock_reclen(svsk));