RDMA/core: Add a helper API rdma_free_hw_stats_struct

Add a new API rdma_free_hw_stats_struct to pair with
rdma_alloc_hw_stats_struct (which is also de-inlined).

This will be useful when there are more alloc/free works in following
patches.

Link: https://lore.kernel.org/r/20211008122439.166063-5-markzhang@nvidia.com
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Mark Zhang <markzhang@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/core/counters.c

@@ -165,7 +165,7 @@ static struct rdma_counter *alloc_and_bind(struct ib_device *dev, u32 port,
 	return counter;
 
 err_mode:
-	kfree(counter->stats);
+	rdma_free_hw_stats_struct(counter->stats);
 err_stats:
 	rdma_restrack_put(&counter->res);
 	kfree(counter);
@@ -186,7 +186,7 @@ static void rdma_counter_free(struct rdma_counter *counter)
 	mutex_unlock(&port_counter->lock);
 
 	rdma_restrack_del(&counter->res);
-	kfree(counter->stats);
+	rdma_free_hw_stats_struct(counter->stats);
 	kfree(counter);
 }
 
@@ -618,7 +618,7 @@ void rdma_counter_init(struct ib_device *dev)
 fail:
 	for (i = port; i >= rdma_start_port(dev); i--) {
 		port_counter = &dev->port_data[port].port_counter;
-		kfree(port_counter->hstats);
+		rdma_free_hw_stats_struct(port_counter->hstats);
 		port_counter->hstats = NULL;
 		mutex_destroy(&port_counter->lock);
 	}
@@ -631,7 +631,7 @@ void rdma_counter_release(struct ib_device *dev)
 
 	rdma_for_each_port(dev, port) {
 		port_counter = &dev->port_data[port].port_counter;
-		kfree(port_counter->hstats);
+		rdma_free_hw_stats_struct(port_counter->hstats);
 		mutex_destroy(&port_counter->lock);
 	}
 }

drivers/infiniband/core/sysfs.c

@@ -755,7 +755,7 @@ static void ib_port_release(struct kobject *kobj)
 	for (i = 0; i != ARRAY_SIZE(port->groups); i++)
 		kfree(port->groups[i].attrs);
 	if (port->hw_stats_data)
-		kfree(port->hw_stats_data->stats);
+		rdma_free_hw_stats_struct(port->hw_stats_data->stats);
 	kfree(port->hw_stats_data);
 	kfree(port);
 }
@@ -919,14 +919,14 @@ alloc_hw_stats_device(struct ib_device *ibdev)
 err_free_data:
 	kfree(data);
 err_free_stats:
-	kfree(stats);
+	rdma_free_hw_stats_struct(stats);
 	return ERR_PTR(-ENOMEM);
 }
 
 void ib_device_release_hw_stats(struct hw_stats_device_data *data)
 {
 	kfree(data->group.attrs);
-	kfree(data->stats);
+	rdma_free_hw_stats_struct(data->stats);
 	kfree(data);
 }
 
@@ -1018,7 +1018,7 @@ alloc_hw_stats_port(struct ib_port *port, struct attribute_group *group)
 err_free_data:
 	kfree(data);
 err_free_stats:
-	kfree(stats);
+	rdma_free_hw_stats_struct(stats);
 	return ERR_PTR(-ENOMEM);
 }
 

drivers/infiniband/core/verbs.c

@@ -2976,3 +2976,38 @@ bool __rdma_block_iter_next(struct ib_block_iter *biter)
 	return true;
 }
 EXPORT_SYMBOL(__rdma_block_iter_next);
+
+/**
+ * rdma_alloc_hw_stats_struct - Helper function to allocate dynamic struct
+ *   for the drivers.
+ * @descs: array of static descriptors
+ * @num_counters: number of elements in array
+ * @lifespan: milliseconds between updates
+ */
+struct rdma_hw_stats *rdma_alloc_hw_stats_struct(
+	const struct rdma_stat_desc *descs, int num_counters,
+	unsigned long lifespan)
+{
+	struct rdma_hw_stats *stats;
+
+	stats = kzalloc(struct_size(stats, value, num_counters), GFP_KERNEL);
+	if (!stats)
+		return NULL;
+
+	stats->descs = descs;
+	stats->num_counters = num_counters;
+	stats->lifespan = msecs_to_jiffies(lifespan);
+
+	return stats;
+}
+EXPORT_SYMBOL(rdma_alloc_hw_stats_struct);
+
+/**
+ * rdma_free_hw_stats_struct - Helper function to release rdma_hw_stats
+ * @stats: statistics to release
+ */
+void rdma_free_hw_stats_struct(struct rdma_hw_stats *stats)
+{
+	kfree(stats);
+}
+EXPORT_SYMBOL(rdma_free_hw_stats_struct);

include/rdma/ib_verbs.h

@@ -582,31 +582,12 @@ struct rdma_hw_stats {
 };
 
 #define RDMA_HW_STATS_DEFAULT_LIFESPAN 10
-/**
- * rdma_alloc_hw_stats_struct - Helper function to allocate dynamic struct
- *   for drivers.
- * @descs - Array of static descriptors
- * @num_counters - How many elements in array
- * @lifespan - How many milliseconds between updates
- */
-static inline struct rdma_hw_stats *rdma_alloc_hw_stats_struct(
-		const struct rdma_stat_desc *descs, int num_counters,
-		unsigned long lifespan)
-{
-	struct rdma_hw_stats *stats;
 
-	stats = kzalloc(sizeof(*stats) + num_counters * sizeof(u64),
-			GFP_KERNEL);
-	if (!stats)
-		return NULL;
-
-	stats->descs = descs;
-	stats->num_counters = num_counters;
-	stats->lifespan = msecs_to_jiffies(lifespan);
-
-	return stats;
-}
+struct rdma_hw_stats *rdma_alloc_hw_stats_struct(
+	const struct rdma_stat_desc *descs, int num_counters,
+	unsigned long lifespan);
 
+void rdma_free_hw_stats_struct(struct rdma_hw_stats *stats);
 
 /* Define bits for the various functionality this port needs to be supported by
  * the core.