[PATCH v5 1/3] graph: avoid global node ID counter

[<kirankumark@marvell.com>]

From: Kiran Kumar K <kirankumark@marvell.com>

The node id is determined based on a global variable that is
incremented every time a node is created. Adding changes to
remove the global counter. Make sure that the node list is always
ordered by increasing node ids. When creating a new node, pick a free
id which is not allocated.

Signed-off-by: Kiran Kumar K <kirankumark@marvell.com>
---
 lib/graph/graph_populate.c | 11 +++--
 lib/graph/graph_private.h  |  8 ----
 lib/graph/node.c           | 86 ++++++++++++++++++++++++++++++++------
 3 files changed, 82 insertions(+), 23 deletions(-)

diff --git a/lib/graph/graph_populate.c b/lib/graph/graph_populate.c
index 1e6b08319e..026daecb21 100644
--- a/lib/graph/graph_populate.c
+++ b/lib/graph/graph_populate.c
@@ -78,7 +78,6 @@ graph_nodes_populate(struct graph *_graph)
 	struct rte_graph *graph = _graph->graph;
 	struct graph_node *graph_node;
 	rte_edge_t count, nb_edges;
-	const char *parent;
 	rte_node_t pid;
 
 	STAILQ_FOREACH(graph_node, &_graph->node_list, next) {
@@ -94,8 +93,14 @@ graph_nodes_populate(struct graph *_graph)
 		memcpy(node->name, graph_node->node->name, RTE_GRAPH_NAMESIZE);
 		pid = graph_node->node->parent_id;
 		if (pid != RTE_NODE_ID_INVALID) { /* Cloned node */
-			parent = rte_node_id_to_name(pid);
-			memcpy(node->parent, parent, RTE_GRAPH_NAMESIZE);
+			struct node *pnode;
+
+			STAILQ_FOREACH(pnode, node_list_head_get(), next) {
+				if (pnode->id == pid) {
+					memcpy(node->parent, pnode->name, RTE_GRAPH_NAMESIZE);
+					break;
+				}
+			}
 		}
 		node->id = graph_node->node->id;
 		node->parent_id = pid;
diff --git a/lib/graph/graph_private.h b/lib/graph/graph_private.h
index da48d73587..fdaf5649b8 100644
--- a/lib/graph/graph_private.h
+++ b/lib/graph/graph_private.h
@@ -29,14 +29,6 @@ extern int rte_graph_logtype;
 #define graph_info(...) GRAPH_LOG(INFO, __VA_ARGS__)
 #define graph_dbg(...) GRAPH_LOG(DEBUG, __VA_ARGS__)
 
-#define ID_CHECK(id, id_max)                                                   \
-	do {                                                                   \
-		if ((id) >= (id_max)) {                                        \
-			rte_errno = EINVAL;                                    \
-			goto fail;                                             \
-		}                                                              \
-	} while (0)
-
 #define SET_ERR_JMP(err, where, fmt, ...)                                      \
 	do {                                                                   \
 		graph_err(fmt, ##__VA_ARGS__);                                 \
diff --git a/lib/graph/node.c b/lib/graph/node.c
index 63db629da8..5ff8dfcd55 100644
--- a/lib/graph/node.c
+++ b/lib/graph/node.c
@@ -15,9 +15,56 @@
 #include "graph_private.h"
 
 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)
+static struct node *
+node_from_id(rte_node_t id)
+{
+	struct node *node = NULL;
+
+	graph_spinlock_lock();
+	rte_errno = EINVAL;
+	STAILQ_FOREACH(node, &node_list, next) {
+		if (node->id == id) {
+			rte_errno = 0;
+			goto exit;
+		}
+	}
+exit:
+	graph_spinlock_unlock();
+	return node;
+}
+
+static rte_node_t
+next_next_free_id(void)
+{
+	struct node *node;
+	rte_node_t id = 0;
+
+	STAILQ_FOREACH(node, &node_list, next) {
+		if (id < node->id)
+			break;
+		id = node->id + 1;
+	}
+	return id;
+}
+
+static void
+node_insert_ordered(struct node *node)
+{
+	struct node *after, *g;
+
+	after = NULL;
+	STAILQ_FOREACH(g, &node_list, next) {
+		if (g->id < node->id)
+			after = g;
+		else if (g->id > node->id)
+			break;
+	}
+	if (after == NULL)
+		STAILQ_INSERT_HEAD(&node_list, node, next);
+	else
+		STAILQ_INSERT_AFTER(&node_list, after, node, next);
+}
 
 /* Private functions */
 struct node_head *
@@ -116,10 +163,10 @@ __rte_node_register(const struct rte_node_register *reg)
 	}
 
 	node->lcore_id = RTE_MAX_LCORE;
-	node->id = node_id++;
+	node->id = next_next_free_id();
 
-	/* Add the node at tail */
-	STAILQ_INSERT_TAIL(&node_list, node, next);
+	/* Add the node in ordered list */
+	node_insert_ordered(node);
 	graph_spinlock_unlock();
 
 	return node->id;
@@ -194,7 +241,9 @@ rte_node_clone(rte_node_t id, const char *name)
 {
 	struct node *node;
 
-	NODE_ID_CHECK(id);
+	if (node_from_id(id) == NULL)
+		goto fail;
+
 	STAILQ_FOREACH(node, &node_list, next)
 		if (node->id == id)
 			return node_clone(node, name);
@@ -220,7 +269,8 @@ rte_node_id_to_name(rte_node_t id)
 {
 	struct node *node;
 
-	NODE_ID_CHECK(id);
+	if (node_from_id(id) == NULL)
+		goto fail;
 	STAILQ_FOREACH(node, &node_list, next)
 		if (node->id == id)
 			return node->name;
@@ -234,7 +284,8 @@ rte_node_edge_count(rte_node_t id)
 {
 	struct node *node;
 
-	NODE_ID_CHECK(id);
+	if (node_from_id(id) == NULL)
+		goto fail;
 	STAILQ_FOREACH(node, &node_list, next)
 		if (node->id == id)
 			return node->nb_edges;
@@ -303,7 +354,8 @@ 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);
+	if (node_from_id(id) == NULL)
+		goto fail;
 	graph_spinlock_lock();
 
 	STAILQ_FOREACH(node, &node_list, next) {
@@ -330,7 +382,8 @@ rte_node_edge_update(rte_node_t id, rte_edge_t from, const char **next_nodes,
 	rte_edge_t rc = RTE_EDGE_ID_INVALID;
 	struct node *n, *prev;
 
-	NODE_ID_CHECK(id);
+	if (node_from_id(id) == NULL)
+		goto fail;
 	graph_spinlock_lock();
 
 	prev = NULL;
@@ -364,7 +417,8 @@ 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);
+	if (node_from_id(id) == NULL)
+		goto fail;
 	graph_spinlock_lock();
 
 	STAILQ_FOREACH(node, &node_list, next) {
@@ -388,7 +442,8 @@ node_scan_dump(FILE *f, rte_node_t id, bool all)
 	struct node *node;
 
 	RTE_ASSERT(f != NULL);
-	NODE_ID_CHECK(id);
+	if (node_from_id(id) == NULL)
+		goto fail;
 
 	STAILQ_FOREACH(node, &node_list, next) {
 		if (all == true) {
@@ -417,5 +472,12 @@ rte_node_list_dump(FILE *f)
 rte_node_t
 rte_node_max_count(void)
 {
+	rte_node_t node_id = 0;
+	struct node *node;
+
+	STAILQ_FOREACH(node, &node_list, next) {
+		if (node_id < node->id)
+			node_id = node->id;
+	}
 	return node_id;
 }
-- 
2.43.0