Re: [PATCH for-next v10 09/11] RDMA/rxe: Convert read side locking to rcu

[Jason Gunthorpe <jgg@nvidia.com>]

On Fri, Feb 25, 2022 at 01:57:49PM -0600, Bob Pearson wrote:
> Use rcu_read_lock() for protecting read side operations in rxe_pool.c.
> 
> Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
> ---
>  drivers/infiniband/sw/rxe/rxe_pool.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
> index 1d1e10290991..713df1ce2bbc 100644
> --- a/drivers/infiniband/sw/rxe/rxe_pool.c
> +++ b/drivers/infiniband/sw/rxe/rxe_pool.c
> @@ -202,16 +202,15 @@ int __rxe_add_to_pool(struct rxe_pool *pool, struct rxe_pool_elem *elem)
>  void *rxe_pool_get_index(struct rxe_pool *pool, u32 index)
>  {
>  	struct rxe_pool_elem *elem;
> -	unsigned long flags;
>  	void *obj;
>  
> -	spin_lock_irqsave(&pool->xa.xa_lock, flags);
> +	rcu_read_lock();
>  	elem = xa_load(&pool->xa, index);
>  	if (elem && elem->enabled && kref_get_unless_zero(&elem->ref_cnt))
>  		obj = elem->obj;
>  	else
>  		obj = NULL;
> -	spin_unlock_irqrestore(&pool->xa.xa_lock, flags);
> +	rcu_read_unlock();

Where is the kfree_rcu to go along with this?

Jason