Commit 6be8c594 authored by Chuck Lever's avatar Chuck Lever
Browse files

SUNRPC: Refactor recvfrom path dealing with incomplete TCP receives 



Clean up: move exception processing out of the main path.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 7dae1dd7

include/trace/events/sunrpc.h

+31 −0
Original line number Diff line number Diff line
@@ -1503,9 +1503,40 @@ DECLARE_EVENT_CLASS(svcsock_class, 
DEFINE_SVCSOCK_EVENT(udp_send);

DEFINE_SVCSOCK_EVENT(tcp_send);

DEFINE_SVCSOCK_EVENT(tcp_recv);

DEFINE_SVCSOCK_EVENT(tcp_recv_eagain);

DEFINE_SVCSOCK_EVENT(tcp_recv_err);

DEFINE_SVCSOCK_EVENT(data_ready);

DEFINE_SVCSOCK_EVENT(write_space);



TRACE_EVENT(svcsock_tcp_recv_short,

	TP_PROTO(

		const struct svc_xprt *xprt,

		u32 expected,

		u32 received

	),



	TP_ARGS(xprt, expected, received),



	TP_STRUCT__entry(

		__field(u32, expected)

		__field(u32, received)

		__field(unsigned long, flags)

		__string(addr, xprt->xpt_remotebuf)

	),



	TP_fast_assign(

		__entry->expected = expected;

		__entry->received = received;

		__entry->flags = xprt->xpt_flags;

		__assign_str(addr, xprt->xpt_remotebuf);

	),



	TP_printk("addr=%s flags=%s expected=%u received=%u",

		__get_str(addr), show_svc_xprt_flags(__entry->flags),

		__entry->expected, __entry->received

	)

);



TRACE_EVENT(svcsock_tcp_state,

	TP_PROTO(

		const struct svc_xprt *xprt,

net/sunrpc/svcsock.c

+19 −20
Original line number Diff line number Diff line
@@ -968,23 +968,10 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp) 
		svsk->sk_tcplen += len;

		svsk->sk_datalen += len;

	}

	if (len != want || !svc_sock_final_rec(svsk)) {

		svc_tcp_save_pages(svsk, rqstp);

		if (len < 0 && len != -EAGAIN)

			goto err_delete;

		if (len == want)

			svc_tcp_fragment_received(svsk);

		else

			dprintk("svc: incomplete TCP record (%d of %d)\n",

				(int)(svsk->sk_tcplen - sizeof(rpc_fraghdr)),

				svc_sock_reclen(svsk));

		goto err_noclose;

	}



	if (svsk->sk_datalen < 8) {

		svsk->sk_datalen = 0;

		goto err_delete; /* client is nuts. */

	}

	if (len != want || !svc_sock_final_rec(svsk))

		goto err_incomplete;

	if (svsk->sk_datalen < 8)

		goto err_nuts;



	rqstp->rq_arg.len = svsk->sk_datalen;

	rqstp->rq_arg.page_base = 0;
@@ -1019,14 +1006,26 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp) 


	return rqstp->rq_arg.len;



err_incomplete:

	svc_tcp_save_pages(svsk, rqstp);

	if (len < 0 && len != -EAGAIN)

		goto err_delete;

	if (len == want)

		svc_tcp_fragment_received(svsk);

	else

		trace_svcsock_tcp_recv_short(&svsk->sk_xprt,

				svc_sock_reclen(svsk),

				svsk->sk_tcplen - sizeof(rpc_fraghdr));

	goto err_noclose;

error:

	if (len != -EAGAIN)

		goto err_delete;

	dprintk("RPC: TCP recvfrom got EAGAIN\n");

	trace_svcsock_tcp_recv_eagain(&svsk->sk_xprt, 0);

	return 0;

err_nuts:

	svsk->sk_datalen = 0;

err_delete:

	printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",

	       svsk->sk_xprt.xpt_server->sv_name, -len);

	trace_svcsock_tcp_recv_err(&svsk->sk_xprt, len);

	set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);

err_noclose:

	return 0;	/* record not complete */