[PATCH for-next v13 10/10] RDMA/rxe: Cleanup rxe_pool.c

[Bob Pearson <rpearsonhpe@gmail.com>]

Minor cleanup of rxe_pool.c. Add document comment headers for
the subroutines. Increase alignment for pool elements.
Convert some printk's to WARN-ON's.

Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
---
 drivers/infiniband/sw/rxe/rxe_pool.c | 89 +++++++++++++++++++++++-----
 1 file changed, 73 insertions(+), 16 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
index cbe7b05c3b66..3b98650fb971 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.c
+++ b/drivers/infiniband/sw/rxe/rxe_pool.c
@@ -8,7 +8,7 @@
 
 #define RXE_POOL_TIMEOUT	(200)
 #define RXE_POOL_MAX_TIMEOUTS	(3)
-#define RXE_POOL_ALIGN		(16)
+#define RXE_POOL_ALIGN		(64)
 
 static const struct rxe_type_info {
 	const char *name;
@@ -120,24 +120,35 @@ void rxe_pool_cleanup(struct rxe_pool *pool)
 	WARN_ON(!xa_empty(&pool->xa));
 }
 
+/**
+ * rxe_alloc - allocate a new pool object
+ * @pool: object pool
+ *
+ * Context: in task.
+ * Returns: object on success else an ERR_PTR
+ */
 void *rxe_alloc(struct rxe_pool *pool)
 {
 	struct rxe_pool_elem *elem;
 	void *obj;
-	int err;
+	int err = -EINVAL;
 
 	if (WARN_ON(!(pool->flags & RXE_POOL_ALLOC)))
-		return NULL;
+		goto err_out;
+
+	if (WARN_ON(!in_task()))
+		goto err_out;
 
 	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
-		goto err_cnt;
+		goto err_dec;
 
 	obj = kzalloc(pool->elem_size, GFP_KERNEL);
-	if (!obj)
-		goto err_cnt;
+	if (!obj) {
+		err = -ENOMEM;
+		goto err_dec;
+	}
 
 	elem = (struct rxe_pool_elem *)((u8 *)obj + pool->elem_offset);
-
 	elem->pool = pool;
 	elem->obj = obj;
 	kref_init(&elem->ref_cnt);
@@ -154,20 +165,32 @@ void *rxe_alloc(struct rxe_pool *pool)
 
 err_free:
 	kfree(obj);
-err_cnt:
+err_dec:
 	atomic_dec(&pool->num_elem);
-	return NULL;
+err_out:
+	return ERR_PTR(err);
 }
 
+/**
+ * __rxe_add_to_pool - add rdma-core allocated object to rxe object pool
+ * @pool: object pool
+ * @elem: rxe_pool_elem embedded in object
+ *
+ * Context: in task.
+ * Returns: 0 on success else an error
+ */
 int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_elem *elem)
 {
-	int err;
+	int err = -EINVAL;
 
 	if (WARN_ON(pool->flags & RXE_POOL_ALLOC))
-		return -EINVAL;
+		goto err_out;
+
+	if (WARN_ON(!in_task()))
+		goto err_out;
 
 	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
-		goto err_cnt;
+		goto err_dec;
 
 	elem->pool = pool;
 	elem->obj = (u8 *)elem - pool->elem_offset;
@@ -177,15 +200,23 @@ int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_elem *elem)
 	err = xa_alloc_cyclic(&pool->xa, &elem->index, NULL, pool->limit,
 			      &pool->next, GFP_KERNEL);
 	if (err)
-		goto err_cnt;
+		goto err_dec;
 
 	return 0;
 
-err_cnt:
+err_dec:
 	atomic_dec(&pool->num_elem);
-	return -EINVAL;
+err_out:
+	return err;
 }
 
+/**
+ * rxe_pool_get_index - find object in pool with given index
+ * @pool: object pool
+ * @index: index
+ *
+ * Returns: object on success else NULL
+ */
 void *rxe_pool_get_index(struct rxe_pool *pool, u32 index)
 {
 	struct rxe_pool_elem *elem;
@@ -203,6 +234,10 @@ void *rxe_pool_get_index(struct rxe_pool *pool, u32 index)
 	return obj;
 }
 
+/**
+ * rxe_elem_release - complete object when last reference is dropped
+ * @kref: kref contained in rxe_pool_elem
+ */
 static void rxe_elem_release(struct kref *kref)
 {
 	struct rxe_pool_elem *elem = container_of(kref, typeof(*elem), ref_cnt);
@@ -210,6 +245,12 @@ static void rxe_elem_release(struct kref *kref)
 	complete(&elem->complete);
 }
 
+/**
+ * __rxe_cleanup - cleanup object after waiting for all refs to be dropped
+ * @elem: rxe_pool_elem
+ *
+ * Returns: 0 on success else an error
+ */
 int __rxe_cleanup(struct rxe_pool_elem *elem)
 {
 	struct rxe_pool *pool = elem->pool;
@@ -229,7 +270,7 @@ int __rxe_cleanup(struct rxe_pool_elem *elem)
 
 	/* if this is the last call to rxe_put complete the
 	 * object. It is safe to touch elem after this since
-	 * it is freed below
+	 * it is freed below if locally allocated
 	 */
 	__rxe_put(elem);
 
@@ -256,16 +297,32 @@ int __rxe_cleanup(struct rxe_pool_elem *elem)
 	return err;
 }
 
+/**
+ * __rxe_get - takes a ref on the object unless ref count is zero
+ * @elem: rxe_pool_elem embedded in object
+ *
+ * Returns: 1 if reference is added else 0
+ */
 int __rxe_get(struct rxe_pool_elem *elem)
 {
 	return kref_get_unless_zero(&elem->ref_cnt);
 }
 
+/**
+ * __rxe_put - puts a ref on the object
+ * @elem: rxe_pool_elem embedded in object
+ *
+ * Returns: 1 if ref count reaches zero and release called else 0
+ */
 int __rxe_put(struct rxe_pool_elem *elem)
 {
 	return kref_put(&elem->ref_cnt, rxe_elem_release);
 }
 
+/**
+ * __rxe_finalize - enable looking up object from index
+ * @elem: rxe_pool_elem embedded in object
+ */
 void __rxe_finalize(struct rxe_pool_elem *elem)
 {
 	struct xarray *xa = &elem->pool->xa;
-- 
2.32.0