net/mlx5: relax list utility atomic operations

The atomic operation in the list utility no need a barriers because the
critical part are managed by RW lock.

Relax them.

Signed-off-by: Matan Azrad <matan@nvidia.com>
Acked-by: Suanming Mou <suanmingm@nvidia.com>

diff --git a/drivers/net/mlx5/mlx5_utils.c b/drivers/net/mlx5/mlx5_utils.c
index 13c7dbe..daecf37 100644 (file)
--- a/drivers/net/mlx5/mlx5_utils.c
+++ b/drivers/net/mlx5/mlx5_utils.c
@@ -50,13 +50,13 @@ __list_lookup(struct mlx5_list *list, int lcore_index, void *ctx, bool reuse)
                if (list->cb_match(list, entry, ctx) == 0) {
                        if (reuse) {
                                ret = __atomic_add_fetch(&entry->ref_cnt, 1,
-                                                        __ATOMIC_ACQUIRE) - 1;
+                                                        __ATOMIC_RELAXED) - 1;
                                DRV_LOG(DEBUG, "mlx5 list %s entry %p ref: %u.",
                                        list->name, (void *)entry,
                                        entry->ref_cnt);
                        } else if (lcore_index < RTE_MAX_LCORE) {
                                ret = __atomic_load_n(&entry->ref_cnt,
-                                                     __ATOMIC_ACQUIRE);
+                                                     __ATOMIC_RELAXED);
                        }
                        if (likely(ret != 0 || lcore_index == RTE_MAX_LCORE))
                                return entry;
@@ -181,7 +181,7 @@ mlx5_list_register(struct mlx5_list *list, void *ctx)
        list->gen_cnt++;
        rte_rwlock_write_unlock(&list->lock);
        LIST_INSERT_HEAD(&list->cache[lcore_index].h, local_entry, next);
-       __atomic_add_fetch(&list->count, 1, __ATOMIC_ACQUIRE);
+       __atomic_add_fetch(&list->count, 1, __ATOMIC_RELAXED);
        DRV_LOG(DEBUG, "mlx5 list %s entry %p new: %u.", list->name,
                (void *)entry, entry->ref_cnt);
        return local_entry;
@@ -194,7 +194,7 @@ mlx5_list_unregister(struct mlx5_list *list,
        struct mlx5_list_entry *gentry = entry->gentry;
        int lcore_idx;
 
-       if (__atomic_sub_fetch(&entry->ref_cnt, 1, __ATOMIC_ACQUIRE) != 0)
+       if (__atomic_sub_fetch(&entry->ref_cnt, 1, __ATOMIC_RELAXED) != 0)
                return 1;
        lcore_idx = rte_lcore_index(rte_lcore_id());
        MLX5_ASSERT(lcore_idx < RTE_MAX_LCORE);
@@ -207,14 +207,14 @@ mlx5_list_unregister(struct mlx5_list *list,
        } else {
                return 0;
        }
-       if (__atomic_sub_fetch(&gentry->ref_cnt, 1, __ATOMIC_ACQUIRE) != 0)
+       if (__atomic_sub_fetch(&gentry->ref_cnt, 1, __ATOMIC_RELAXED) != 0)
                return 1;
        rte_rwlock_write_lock(&list->lock);
        if (likely(gentry->ref_cnt == 0)) {
                LIST_REMOVE(gentry, next);
                rte_rwlock_write_unlock(&list->lock);
                list->cb_remove(list, gentry);
-               __atomic_sub_fetch(&list->count, 1, __ATOMIC_ACQUIRE);
+               __atomic_sub_fetch(&list->count, 1, __ATOMIC_RELAXED);
                DRV_LOG(DEBUG, "mlx5 list %s entry %p removed.",
                        list->name, (void *)gentry);
                return 0;