net/mlx5: CQ hold/put API

Now as the CQ table is per EQ, add an API to hold/put CQ to be used from
eq.c in downstream patch.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Gal Pressman <galp@mellanox.com>

2 files changed, 30 insertions, 23 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cq.c b/drivers/net/ethernet/mellanox/mlx5/core/cq.c
index f6e478d05ecc..06dc7bd302ed 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/cq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/cq.c
@@ -58,8 +58,7 @@ void mlx5_cq_tasklet_cb(unsigned long data)
                                  tasklet_ctx.list) {
                 list_del_init(&mcq->tasklet_ctx.list);
                 mcq->tasklet_ctx.comp(mcq);
-                if (refcount_dec_and_test(&mcq->refcount))
-                        complete(&mcq->free);
+                mlx5_cq_put(mcq);
                 if (time_after(jiffies, end))
                         break;
         }
@@ -80,23 +79,31 @@ static void mlx5_add_cq_to_tasklet(struct mlx5_core_cq *cq)
          * still arrive.
          */
         if (list_empty_careful(&cq->tasklet_ctx.list)) {
-                refcount_inc(&cq->refcount);
+                mlx5_cq_hold(cq);
                 list_add_tail(&cq->tasklet_ctx.list, &tasklet_ctx->list);
         }
         spin_unlock_irqrestore(&tasklet_ctx->lock, flags);
 }
 
-void mlx5_cq_completion(struct mlx5_eq *eq, u32 cqn)
+/* caller must eventually call mlx5_cq_put on the returned cq */
+static struct mlx5_core_cq *mlx5_eq_cq_get(struct mlx5_eq *eq, u32 cqn)
 {
         struct mlx5_cq_table *table = &eq->cq_table;
-        struct mlx5_core_cq *cq;
+        struct mlx5_core_cq *cq = NULL;
 
         spin_lock(&table->lock);
         cq = radix_tree_lookup(&table->tree, cqn);
         if (likely(cq))
-                refcount_inc(&cq->refcount);
+                mlx5_cq_hold(cq);
         spin_unlock(&table->lock);
 
+        return cq;
+}
+
+void mlx5_cq_completion(struct mlx5_eq *eq, u32 cqn)
+{
+        struct mlx5_core_cq *cq = mlx5_eq_cq_get(eq, cqn);
+
         if (unlikely(!cq)) {
                 mlx5_core_warn(eq->dev, "Completion event for bogus CQ 0x%x\n", cqn);
                 return;
@@ -106,22 +113,12 @@ void mlx5_cq_completion(struct mlx5_eq *eq, u32 cqn)
 
         cq->comp(cq);
 
-        if (refcount_dec_and_test(&cq->refcount))
-                complete(&cq->free);
+        mlx5_cq_put(cq);
 }
 
 void mlx5_cq_event(struct mlx5_eq *eq, u32 cqn, int event_type)
 {
-        struct mlx5_cq_table *table = &eq->cq_table;
-        struct mlx5_core_cq *cq;
-
-        spin_lock(&table->lock);
-
-        cq = radix_tree_lookup(&table->tree, cqn);
-        if (likely(cq))
-                refcount_inc(&cq->refcount);
-
-        spin_unlock(&table->lock);
+        struct mlx5_core_cq *cq = mlx5_eq_cq_get(eq, cqn);
 
         if (unlikely(!cq)) {
                 mlx5_core_warn(eq->dev, "Async event for bogus CQ 0x%x\n", cqn);
@@ -130,8 +127,7 @@ void mlx5_cq_event(struct mlx5_eq *eq, u32 cqn, int event_type)
 
         cq->event(cq, event_type);
 
-        if (refcount_dec_and_test(&cq->refcount))
-                complete(&cq->free);
+        mlx5_cq_put(cq);
 }
 
 int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
@@ -158,7 +154,8 @@ int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
         cq->cons_index = 0;
         cq->arm_sn     = 0;
         cq->eq         = eq;
-        refcount_set(&cq->refcount, 1);
+        refcount_set(&cq->refcount, 0);
+        mlx5_cq_hold(cq);
         init_completion(&cq->free);
         if (!cq->comp)
                 cq->comp = mlx5_add_cq_to_tasklet;
@@ -221,8 +218,7 @@ int mlx5_core_destroy_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq)
         synchronize_irq(cq->irqn);
 
         mlx5_debug_cq_remove(dev, cq);
-        if (refcount_dec_and_test(&cq->refcount))
-                complete(&cq->free);
+        mlx5_cq_put(cq);
         wait_for_completion(&cq->free);
 
         return 0;
diff --git a/include/linux/mlx5/cq.h b/include/linux/mlx5/cq.h
index 06ba425a6ad7..445ad194e0fe 100644
--- a/include/linux/mlx5/cq.h
+++ b/include/linux/mlx5/cq.h
@@ -172,6 +172,17 @@ static inline void mlx5_cq_arm(struct mlx5_core_cq *cq, u32 cmd,
         mlx5_write64(doorbell, uar_page + MLX5_CQ_DOORBELL, NULL);
 }
 
+static inline void mlx5_cq_hold(struct mlx5_core_cq *cq)
+{
+        refcount_inc(&cq->refcount);
+}
+
+static inline void mlx5_cq_put(struct mlx5_core_cq *cq)
+{
+        if (refcount_dec_and_test(&cq->refcount))
+                complete(&cq->free);
+}
+
 int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
                         u32 *in, int inlen);
 int mlx5_core_destroy_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq);