[PATCH v2 2/2] net/ice: fix shaper profile reference count tracking

[Ciara Loftus <ciara.loftus@intel.com>]

Currently, when a TM node is added with a shaper profile assigned,
the profile's reference count is not incremented. Equally, when a node
is deleted, the count is not decremented. As a result, the guard that
blocks deletion of an in-use profile never triggers, allowing the profile
to be freed while nodes still hold a pointer to it.

Fix by maintaining the reference count correctly when nodes take or
release a shaper profile, so that deletion of an in-use profile is
properly rejected.

Fixes: 8c481c3bb65b ("net/ice: support queue and queue group bandwidth limit")
Cc: stable@dpdk.org

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
---
 drivers/net/intel/ice/ice_tm.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/intel/ice/ice_tm.c b/drivers/net/intel/ice/ice_tm.c
index 2bb684bb02..015a827d7a 100644
--- a/drivers/net/intel/ice/ice_tm.c
+++ b/drivers/net/intel/ice/ice_tm.c
@@ -456,6 +456,8 @@ ice_tm_node_add(struct rte_eth_dev *dev, uint32_t node_id,
 		tm_node->parent = NULL;
 		tm_node->reference_count = 0;
 		tm_node->shaper_profile = shaper_profile;
+		if (shaper_profile != NULL)
+			shaper_profile->reference_count++;
 		tm_node->children = RTE_PTR_ADD(tm_node, sizeof(struct ice_tm_node));
 		tm_node->params = *params;
 		pf->tm_conf.root = tm_node;
@@ -518,6 +520,8 @@ ice_tm_node_add(struct rte_eth_dev *dev, uint32_t node_id,
 	tm_node->parent = parent_node;
 	tm_node->level = level_id;
 	tm_node->shaper_profile = shaper_profile;
+	if (shaper_profile != NULL)
+		shaper_profile->reference_count++;
 	tm_node->children = RTE_PTR_ADD(tm_node, sizeof(struct ice_tm_node));
 	tm_node->parent->children[tm_node->parent->reference_count++] = tm_node;
 	tm_node->params = *params;
@@ -568,6 +572,8 @@ ice_tm_node_delete(struct rte_eth_dev *dev, uint32_t node_id,
 
 	/* root node */
 	if (tm_node->level == 0) {
+		if (tm_node->shaper_profile != NULL)
+			tm_node->shaper_profile->reference_count--;
 		rte_free(tm_node);
 		pf->tm_conf.root = NULL;
 		return 0;
@@ -582,6 +588,8 @@ ice_tm_node_delete(struct rte_eth_dev *dev, uint32_t node_id,
 		tm_node->parent->children[j] = tm_node->parent->children[j + 1];
 
 	tm_node->parent->reference_count--;
+	if (tm_node->shaper_profile != NULL)
+		tm_node->shaper_profile->reference_count--;
 	rte_free(tm_node);
 
 	return 0;
-- 
2.43.0