infra: remove control_output_node

Remove all references to control output node and the associated code.
This control_output node is no longer required as all features are
implemented as nodes.

Signed-off-by: Christophe Fontaine <[email protected]>

Author: christophefontaine

docs/graph.svg

@@ -7,6 +7,5 @@
 
 #include <rte_byteorder.h>
 
-void loopback_tx(struct rte_mbuf *m);
 control_input_t loopback_get_control_id(void);
 void loopback_input_add_type(rte_be16_t eth_type, const char *next_node);

modules/infra/control/control_output.c

@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright (c) 2024 Christophe Fontaine
+
+#include "loopback.h"
+
+#include <gr_graph.h>
+#include <gr_infra.h>
+#include <gr_ip4_datapath.h>
+#include <gr_ip6_datapath.h>
+#include <gr_log.h>
+#include <gr_loopback.h>
+#include <gr_trace.h>
+
+#include <rte_malloc.h>
+
+#include <linux/if_tun.h>
+#include <sys/uio.h>
+
+static uint16_t
+loopback_output_process(struct rte_graph *, struct rte_node *, void **objs, uint16_t nb_objs) {
+	struct iface_info_loopback *lo;
+	struct iovec iov[2];
+	struct mbuf_data *d;
+	struct rte_mbuf *m;
+	struct tun_pi pi;
+	char *data;
+
+	for (uint16_t i = 0; i < nb_objs; i++) {
+		m = objs[i];
+		d = mbuf_data(m);
+
+		lo = (struct iface_info_loopback *)d->iface->info;
+		if (rte_pktmbuf_linearize(m) == 0) {
+			data = rte_pktmbuf_mtod(m, char *);
+		} else {
+			data = rte_malloc(NULL, rte_pktmbuf_pkt_len(m), 0);
+			if (data == NULL) {
+				LOG(ERR, "rte_malloc failed %s", rte_strerror(rte_errno));
+				goto next;
+			}
+			// with a non-contiguous mbuf, rte_pktmbuf_read returns a pointer
+			// to the user provided buffer.
+			rte_pktmbuf_read(m, 0, rte_pktmbuf_pkt_len(m), data);
+		}
+		pi.flags = 0;
+		if ((data[0] & 0xf0) == 0x40)
+			pi.proto = RTE_BE16(RTE_ETHER_TYPE_IPV4);
+		else if ((data[0] & 0xf0) == 0x60)
+			pi.proto = RTE_BE16(RTE_ETHER_TYPE_IPV6);
+		else {
+			LOG(ERR, "Bad proto: 0x%x - drop packet", data[0]);
+			goto next;
+		}
+		// Do not retry even in case of  if EAGAIN || EWOULDBLOCK
+		// If the tun device queue is full, something really bad is
+		// already happening on the management plane side.
+		iov[0].iov_base = &pi;
+		iov[0].iov_len = sizeof(pi);
+		iov[1].iov_base = data;
+		iov[1].iov_len = rte_pktmbuf_pkt_len(m);
+
+		if (writev(lo->fd, iov, ARRAY_DIM(iov)) < 0) {
+			// The user messed up and removed gr-loopX
+			// release resources on our side to try to recover
+			if (errno == EBADFD) {
+				iface_destroy(d->iface->id);
+			}
+			LOG(ERR, "write to tun device failed %s", strerror(errno));
+		}
+
+next:
+		if (!rte_pktmbuf_is_contiguous(m))
+			rte_free(data);
+		rte_pktmbuf_free(m);
+	}
+	return nb_objs;
+}
+
+static struct rte_node_register loopback_output_node = {
+	.name = "loopback_output",
+	.process = loopback_output_process,
+	.nb_edges = 0,
+	.next_nodes = {},
+};
+
+static void loopback_output_register(void) {
+	ip_output_register_interface_type(GR_IFACE_TYPE_LOOPBACK, "loopback_output");
+	ip6_output_register_interface_type(GR_IFACE_TYPE_LOOPBACK, "loopback_output");
+}
+
+static struct gr_node_info info = {
+	.node = &loopback_output_node,
+	.register_callback = loopback_output_register,
+};
+
+GR_NODE_REGISTER(info);

modules/infra/control/gr_loopback.h

@@ -1,8 +1,9 @@
 // SPDX-License-Identifier: BSD-3-Clause
 // Copyright (c) 2024 Christophe Fontaine
 
+#include "loopback.h"
+
 #include <gr_control_input.h>
-#include <gr_control_output.h>
 #include <gr_eth.h>
 #include <gr_iface.h>
 #include <gr_infra.h>
@@ -29,69 +30,12 @@
 static struct rte_mempool *loopback_pool;
 static struct event_base *ev_base;
 
-struct iface_info_loopback {
-	int fd;
-	struct event *ev;
-};
-
 static void finalize_fd(struct event *ev, void * /*priv*/) {
 	int fd = event_get_fd(ev);
 	if (fd >= 0)
 		close(fd);
 }
 
-void loopback_tx(struct rte_mbuf *m) {
-	struct mbuf_data *d = mbuf_data(m);
-	struct iface_info_loopback *lo;
-	struct iovec iov[2];
-	struct tun_pi pi;
-	char *data;
-
-	lo = (struct iface_info_loopback *)d->iface->info;
-	if (rte_pktmbuf_linearize(m) == 0) {
-		data = rte_pktmbuf_mtod(m, char *);
-	} else {
-		data = rte_malloc(NULL, rte_pktmbuf_pkt_len(m), 0);
-		if (data == NULL) {
-			LOG(ERR, "rte_malloc failed %s", rte_strerror(rte_errno));
-			goto end;
-		}
-		// with a non-contiguous mbuf, rte_pktmbuf_read returns a pointer
-		// to the user provided buffer.
-		rte_pktmbuf_read(m, 0, rte_pktmbuf_pkt_len(m), data);
-	}
-	pi.flags = 0;
-	if ((data[0] & 0xf0) == 0x40)
-		pi.proto = RTE_BE16(RTE_ETHER_TYPE_IPV4);
-	else if ((data[0] & 0xf0) == 0x60)
-		pi.proto = RTE_BE16(RTE_ETHER_TYPE_IPV6);
-	else {
-		LOG(ERR, "Bad proto: 0x%x - drop packet", data[0]);
-		goto end;
-	}
-	// Do not retry even in case of  if EAGAIN || EWOULDBLOCK
-	// If the tun device queue is full, something really bad is
-	// already happening on the management plane side.
-	iov[0].iov_base = &pi;
-	iov[0].iov_len = sizeof(pi);
-	iov[1].iov_base = data;
-	iov[1].iov_len = rte_pktmbuf_pkt_len(m);
-
-	if (writev(lo->fd, iov, ARRAY_DIM(iov)) < 0) {
-		// The user messed up and removed gr-loopX
-		// release resources on our side to try to recover
-		if (errno == EBADFD) {
-			iface_destroy(d->iface->id);
-		}
-		LOG(ERR, "write to tun device failed %s", strerror(errno));
-	}
-
-end:
-	if (!rte_pktmbuf_is_contiguous(m))
-		rte_free(data);
-	rte_pktmbuf_free(m);
-}
-
 static void iface_loopback_poll(evutil_socket_t, short reason, void *ev_iface) {
 	struct eth_input_mbuf_data *e;
 	struct iface_info_loopback *lo;

modules/infra/control/loop_output.c

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright (c) 2025 Christophe Fontaine
+
+#pragma once
+
+struct iface_info_loopback {
+	int fd;
+	struct event *ev;
+};

modules/infra/control/loopback.c

@@ -2,8 +2,8 @@
 # Copyright (c) 2023 Robin Jarry
 
 src += files(
-  'control_output.c',
   'iface.c',
+  'loop_output.c',
   'loopback.c',
   'main_loop.c',
   'mempool.c',

modules/infra/control/loopback.h

@@ -421,7 +421,7 @@ static void worker_fini(struct event_base *) {
 
 static struct gr_module worker_module = {
 	.name = "worker",
-	.depends_on = "control_output",
+	.depends_on = "graph",
 	.init = worker_init,
 	.fini = worker_fini,
 };