net/mlx5: fix meter action pool protection

The ASO meter action with flows creation could be supported on
multiple threads. The meter pools were created to manage the meter
object resources, if there is no room in the current meter pool then
resize the meter pool to the new pool size and free the old one.

There's a race condition while one thread resizes the meter pool and
the old pool resource be freed, and another thread query the meter
object by index on the old pool, the return value is invalid.

This patch adds a read-write lock to protect the pool resource while
resizing and query.

Fixes: a5835d530f00 ("net/mlx5: optimize Rx queue match")
Cc: stable@dpdk.org
Signed-off-by: Jiawei Wang <jiaweiw@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index b90752c..4ba850a 100644 (file)
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -632,6 +632,7 @@ mlx5_aso_flow_mtrs_mng_init(struct mlx5_dev_ctx_shared *sh)
                }
                if (sh->meter_aso_en) {
                        rte_spinlock_init(&sh->mtrmng->pools_mng.mtrsl);
+                       rte_rwlock_init(&sh->mtrmng->pools_mng.resize_mtrwl);
                        LIST_INIT(&sh->mtrmng->pools_mng.meters);
                }
                sh->mtrmng->def_policy_id = MLX5_INVALID_POLICY_ID;

diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
index 5e88dfc..39c001a 100644 (file)
--- a/drivers/net/mlx5/mlx5.h
+++ b/drivers/net/mlx5/mlx5.h
@@ -895,6 +895,7 @@ struct mlx5_aso_mtr_pools_mng {
        volatile uint16_t n_valid; /* Number of valid pools. */
        uint16_t n; /* Number of pools. */
        rte_spinlock_t mtrsl; /* The ASO flow meter free list lock. */
+       rte_rwlock_t resize_mtrwl; /* Lock for resize objects. */
        struct aso_meter_list meters; /* Free ASO flow meter list. */
        struct mlx5_aso_sq sq; /*SQ using by ASO flow meter. */
        struct mlx5_aso_mtr_pool **pools; /* ASO flow meter pool array. */

diff --git a/drivers/net/mlx5/mlx5_flow.h b/drivers/net/mlx5/mlx5_flow.h
index 01ecfab..5509c28 100644 (file)
--- a/drivers/net/mlx5/mlx5_flow.h
+++ b/drivers/net/mlx5/mlx5_flow.h
@@ -1337,7 +1337,9 @@ mlx5_aso_meter_by_idx(struct mlx5_priv *priv, uint32_t idx)
        /* Decrease to original index. */
        idx--;
        MLX5_ASSERT(idx / MLX5_ASO_MTRS_PER_POOL < pools_mng->n);
+       rte_rwlock_read_lock(&pools_mng->resize_mtrwl);
        pool = pools_mng->pools[idx / MLX5_ASO_MTRS_PER_POOL];
+       rte_rwlock_read_unlock(&pools_mng->resize_mtrwl);
        return &pool->mtrs[idx % MLX5_ASO_MTRS_PER_POOL];
 }
 

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 22081dd..8962d26 100644 (file)
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -6398,14 +6398,17 @@ flow_dv_mtr_pool_create(struct rte_eth_dev *dev, struct mlx5_aso_mtr **mtr_free)
                return NULL;
        }
        pool->devx_obj = dcs;
+       rte_rwlock_write_lock(&pools_mng->resize_mtrwl);
        pool->index = pools_mng->n_valid;
        if (pool->index == pools_mng->n && flow_dv_mtr_container_resize(dev)) {
                mlx5_free(pool);
                claim_zero(mlx5_devx_cmd_destroy(dcs));
+               rte_rwlock_write_unlock(&pools_mng->resize_mtrwl);
                return NULL;
        }
        pools_mng->pools[pool->index] = pool;
        pools_mng->n_valid++;
+       rte_rwlock_write_unlock(&pools_mng->resize_mtrwl);
        for (i = 1; i < MLX5_ASO_MTRS_PER_POOL; ++i) {
                pool->mtrs[i].offset = i;
                LIST_INSERT_HEAD(&pools_mng->meters, &pool->mtrs[i], next);

diff --git a/drivers/net/mlx5/mlx5_flow_meter.c b/drivers/net/mlx5/mlx5_flow_meter.c
index ba4e9fc..f4a7b69 100644 (file)
--- a/drivers/net/mlx5/mlx5_flow_meter.c
+++ b/drivers/net/mlx5/mlx5_flow_meter.c
@@ -1789,24 +1789,21 @@ mlx5_flow_meter_find(struct mlx5_priv *priv, uint32_t meter_id,
        struct mlx5_aso_mtr_pools_mng *pools_mng =
                                &priv->sh->mtrmng->pools_mng;
        union mlx5_l3t_data data;
+       uint16_t n_valid;
 
        if (priv->sh->meter_aso_en) {
-               rte_spinlock_lock(&pools_mng->mtrsl);
-               if (!pools_mng->n_valid || !priv->mtr_idx_tbl) {
-                       rte_spinlock_unlock(&pools_mng->mtrsl);
+               rte_rwlock_read_lock(&pools_mng->resize_mtrwl);
+               n_valid = pools_mng->n_valid;
+               rte_rwlock_read_unlock(&pools_mng->resize_mtrwl);
+               if (!n_valid || !priv->mtr_idx_tbl ||
+                   (mlx5_l3t_get_entry(priv->mtr_idx_tbl, meter_id, &data) ||
+                   !data.dword))
                        return NULL;
-               }
-               if (mlx5_l3t_get_entry(priv->mtr_idx_tbl, meter_id, &data) ||
-                       !data.dword) {
-                       rte_spinlock_unlock(&pools_mng->mtrsl);
-                       return NULL;
-               }
                if (mtr_idx)
                        *mtr_idx = data.dword;
                aso_mtr = mlx5_aso_meter_by_idx(priv, data.dword);
                /* Remove reference taken by the mlx5_l3t_get_entry. */
                mlx5_l3t_clear_entry(priv->mtr_idx_tbl, meter_id);
-               rte_spinlock_unlock(&pools_mng->mtrsl);
                if (!aso_mtr || aso_mtr->state == ASO_METER_FREE)
                        return NULL;
                return &aso_mtr->fm;