page_pool: introduce page_pool_free and use in mlx5

In case driver fails to register the page_pool with XDP return API (via
xdp_rxq_info_reg_mem_model()), then the driver can free the page_pool
resources more directly than calling page_pool_destroy(), which does a
unnecessarily RCU free procedure.

This patch is preparing for removing page_pool_destroy(), from driver
invocation.

Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Reviewed-by: Tariq Toukan <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 205af7bd6d09..41391b5dc14c 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -292,17 +292,24 @@ static void __page_pool_empty_ring(struct page_pool *pool)
 	}
 }
 
+void __page_pool_free(struct page_pool *pool)
+{
+	WARN(pool->alloc.count, "API usage violation");
+	WARN(!ptr_ring_empty(&pool->ring), "ptr_ring is not empty");
+
+	ptr_ring_cleanup(&pool->ring, NULL);
+	kfree(pool);
+}
+EXPORT_SYMBOL(__page_pool_free);
+
 static void __page_pool_destroy_rcu(struct rcu_head *rcu)
 {
 	struct page_pool *pool;
 
 	pool = container_of(rcu, struct page_pool, rcu);
 
-	WARN(pool->alloc.count, "API usage violation");
-
 	__page_pool_empty_ring(pool);
-	ptr_ring_cleanup(&pool->ring, NULL);
-	kfree(pool);
+	__page_pool_free(pool);
 }
 
 /* Cleanup and release resources */