graph: implement node operations

Adding node-specific API implementation like cloning node, updating
edges for the node, shrinking edges of a node, retrieving edges of a
node.

Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: Kiran Kumar K <kirankumark@marvell.com>
Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>

lib/librte_graph/graph_private.h

@@ -13,6 +13,16 @@
 
 #include "rte_graph.h"
 
+
+#define ID_CHECK(id, id_max)                                                   \
+	do {                                                                   \
+		if ((id) >= (id_max)) {                                        \
+			rte_errno = EINVAL;                                    \
+			goto fail;                                             \
+		}                                                              \
+	} while (0)
+
+
 /**
  * @internal
  *

lib/librte_graph/node.c

@@ -17,6 +17,8 @@
 static struct node_head node_list = STAILQ_HEAD_INITIALIZER(node_list);
 static rte_node_t node_id;
 
+#define NODE_ID_CHECK(id) ID_CHECK(id, node_id)
+
 /* Private functions */
 struct node_head *
 node_list_head_get(void)
@@ -111,3 +113,272 @@ __rte_node_register(const struct rte_node_register *reg)
 	return RTE_NODE_ID_INVALID;
 }
 
+static int
+clone_name(struct rte_node_register *reg, struct node *node, const char *name)
+{
+	ssize_t sz, rc;
+
+#define SZ RTE_NODE_NAMESIZE
+	rc = rte_strscpy(reg->name, node->name, SZ);
+	if (rc < 0)
+		goto fail;
+	sz = rc;
+	rc = rte_strscpy(reg->name + sz, "-", RTE_MAX((int16_t)(SZ - sz), 0));
+	if (rc < 0)
+		goto fail;
+	sz += rc;
+	sz = rte_strscpy(reg->name + sz, name, RTE_MAX((int16_t)(SZ - sz), 0));
+	if (sz < 0)
+		goto fail;
+
+	return 0;
+fail:
+	rte_errno = E2BIG;
+	return -rte_errno;
+}
+
+static rte_node_t
+node_clone(struct node *node, const char *name)
+{
+	rte_node_t rc = RTE_NODE_ID_INVALID;
+	struct rte_node_register *reg;
+	rte_edge_t i;
+
+	/* Don't allow to clone a node from a cloned node */
+	if (node->parent_id != RTE_NODE_ID_INVALID) {
+		rte_errno = EEXIST;
+		goto fail;
+	}
+
+	/* Check for duplicate name */
+	if (node_has_duplicate_entry(name))
+		goto fail;
+
+	reg = calloc(1, sizeof(*reg) + (sizeof(char *) * node->nb_edges));
+	if (reg == NULL) {
+		rte_errno = ENOMEM;
+		goto fail;
+	}
+
+	/* Clone the source node */
+	reg->flags = node->flags;
+	reg->process = node->process;
+	reg->init = node->init;
+	reg->fini = node->fini;
+	reg->nb_edges = node->nb_edges;
+	reg->parent_id = node->id;
+
+	for (i = 0; i < node->nb_edges; i++)
+		reg->next_nodes[i] = node->next_nodes[i];
+
+	/* Naming ceremony of the new node. name is node->name + "-" + name */
+	if (clone_name(reg, node, name))
+		goto free;
+
+	rc = __rte_node_register(reg);
+free:
+	free(reg);
+fail:
+	return rc;
+}
+
+rte_node_t
+rte_node_clone(rte_node_t id, const char *name)
+{
+	struct node *node;
+
+	NODE_ID_CHECK(id);
+	STAILQ_FOREACH(node, &node_list, next)
+		if (node->id == id)
+			return node_clone(node, name);
+
+fail:
+	return RTE_NODE_ID_INVALID;
+}
+
+rte_node_t
+rte_node_from_name(const char *name)
+{
+	struct node *node;
+
+	STAILQ_FOREACH(node, &node_list, next)
+		if (strncmp(node->name, name, RTE_NODE_NAMESIZE) == 0)
+			return node->id;
+
+	return RTE_NODE_ID_INVALID;
+}
+
+char *
+rte_node_id_to_name(rte_node_t id)
+{
+	struct node *node;
+
+	NODE_ID_CHECK(id);
+	STAILQ_FOREACH(node, &node_list, next)
+		if (node->id == id)
+			return node->name;
+
+fail:
+	return NULL;
+}
+
+rte_edge_t
+rte_node_edge_count(rte_node_t id)
+{
+	struct node *node;
+
+	NODE_ID_CHECK(id);
+	STAILQ_FOREACH(node, &node_list, next)
+		if (node->id == id)
+			return node->nb_edges;
+fail:
+	return RTE_EDGE_ID_INVALID;
+}
+
+static rte_edge_t
+edge_update(struct node *node, struct node *prev, rte_edge_t from,
+	    const char **next_nodes, rte_edge_t nb_edges)
+{
+	rte_edge_t i, max_edges, count = 0;
+	struct node *new_node;
+	bool need_realloc;
+	size_t sz;
+
+	if (from == RTE_EDGE_ID_INVALID)
+		from = node->nb_edges;
+
+	/* Don't create hole in next_nodes[] list */
+	if (from > node->nb_edges) {
+		rte_errno = ENOMEM;
+		goto fail;
+	}
+
+	/* Remove me from list */
+	STAILQ_REMOVE(&node_list, node, node, next);
+
+	/* Allocate the storage space for new node if required */
+	max_edges = from + nb_edges;
+	need_realloc = max_edges > node->nb_edges;
+	if (need_realloc) {
+		sz = sizeof(struct node) + (max_edges * RTE_NODE_NAMESIZE);
+		new_node = realloc(node, sz);
+		if (new_node == NULL) {
+			rte_errno = ENOMEM;
+			goto restore;
+		} else {
+			node = new_node;
+		}
+	}
+
+	/* Update the new nodes name */
+	for (i = from; i < max_edges; i++, count++) {
+		if (rte_strscpy(node->next_nodes[i], next_nodes[count],
+				RTE_NODE_NAMESIZE) < 0) {
+			rte_errno = E2BIG;
+			goto restore;
+		}
+	}
+restore:
+	/* Update the linked list to point new node address in prev node */
+	if (prev)
+		STAILQ_INSERT_AFTER(&node_list, prev, node, next);
+	else
+		STAILQ_INSERT_HEAD(&node_list, node, next);
+
+	if (need_realloc)
+		node->nb_edges = max_edges;
+
+fail:
+	return count;
+}
+
+rte_edge_t
+rte_node_edge_shrink(rte_node_t id, rte_edge_t size)
+{
+	rte_edge_t rc = RTE_EDGE_ID_INVALID;
+	struct node *node;
+
+	NODE_ID_CHECK(id);
+	graph_spinlock_lock();
+
+	STAILQ_FOREACH(node, &node_list, next) {
+		if (node->id == id) {
+			if (node->nb_edges < size) {
+				rte_errno = E2BIG;
+				goto fail;
+			}
+			node->nb_edges = size;
+			rc = size;
+			break;
+		}
+	}
+
+fail:
+	graph_spinlock_unlock();
+	return rc;
+}
+
+rte_edge_t
+rte_node_edge_update(rte_node_t id, rte_edge_t from, const char **next_nodes,
+		     uint16_t nb_edges)
+{
+	rte_edge_t rc = RTE_EDGE_ID_INVALID;
+	struct node *n, *prev;
+
+	NODE_ID_CHECK(id);
+	graph_spinlock_lock();
+
+	prev = NULL;
+	STAILQ_FOREACH(n, &node_list, next) {
+		if (n->id == id) {
+			rc = edge_update(n, prev, from, next_nodes, nb_edges);
+			break;
+		}
+		prev = n;
+	}
+
+	graph_spinlock_unlock();
+fail:
+	return rc;
+}
+
+static rte_node_t
+node_copy_edges(struct node *node, char *next_nodes[])
+{
+	rte_edge_t i;
+
+	for (i = 0; i < node->nb_edges; i++)
+		next_nodes[i] = node->next_nodes[i];
+
+	return i;
+}
+
+rte_node_t
+rte_node_edge_get(rte_node_t id, char *next_nodes[])
+{
+	rte_node_t rc = RTE_NODE_ID_INVALID;
+	struct node *node;
+
+	NODE_ID_CHECK(id);
+	graph_spinlock_lock();
+
+	STAILQ_FOREACH(node, &node_list, next) {
+		if (node->id == id) {
+			if (next_nodes == NULL)
+				rc = sizeof(char *) * node->nb_edges;
+			else
+				rc = node_copy_edges(node, next_nodes);
+			break;
+		}
+	}
+
+	graph_spinlock_unlock();
+fail:
+	return rc;
+}
+
+rte_node_t
+rte_node_max_count(void)
+{
+	return node_id;
+}

lib/librte_graph/rte_graph_version.map

@@ -3,5 +3,15 @@ EXPERIMENTAL {
 
 	__rte_node_register;
 
+	rte_node_clone;
+	rte_node_edge_count;
+	rte_node_edge_get;
+	rte_node_edge_shrink;
+	rte_node_edge_update;
+	rte_node_from_name;
+	rte_node_id_to_name;
+	rte_node_list_dump;
+	rte_node_max_count;
+
 	local: *;
 };