Commit b54c2a25 authored by Bob Pearson's avatar Bob Pearson Committed by Jason Gunthorpe
Browse files

RDMA/rxe: Convert read side locking to rcu 

Use rcu_read_lock() for protecting read side operations in rxe_pool.c.

Link: https://lore.kernel.org/r/20220612223434.31462-3-rpearsonhpe@gmail.com


Signed-off-by: default avatarBob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 215d0a75

drivers/infiniband/sw/rxe/rxe_pool.c

+8 −16
Original line number Diff line number Diff line
@@ -197,16 +197,15 @@ void *rxe_pool_get_index(struct rxe_pool *pool, u32 index) 
{

	struct rxe_pool_elem *elem;

	struct xarray *xa = &pool->xa;

	unsigned long flags;

	void *obj;



	xa_lock_irqsave(xa, flags);

	rcu_read_lock();

	elem = xa_load(xa, index);

	if (elem && kref_get_unless_zero(&elem->ref_cnt))

		obj = elem->obj;

	else

		obj = NULL;

	xa_unlock_irqrestore(xa, flags);

	rcu_read_unlock();



	return obj;

}
@@ -223,7 +222,6 @@ int __rxe_cleanup(struct rxe_pool_elem *elem, bool sleepable) 
	struct rxe_pool *pool = elem->pool;

	struct xarray *xa = &pool->xa;

	static int timeout = RXE_POOL_TIMEOUT;

	unsigned long flags;

	int ret, err = 0;

	void *xa_ret;
@@ -233,9 +231,7 @@ int __rxe_cleanup(struct rxe_pool_elem *elem, bool sleepable) 
	/* erase xarray entry to prevent looking up

	 * the pool elem from its index

	 */

	xa_lock_irqsave(xa, flags);

	xa_ret = __xa_erase(xa, elem->index);

	xa_unlock_irqrestore(xa, flags);

	xa_ret = xa_erase(xa, elem->index);

	WARN_ON(xa_err(xa_ret));



	/* if this is the last call to rxe_put complete the
@@ -280,7 +276,7 @@ int __rxe_cleanup(struct rxe_pool_elem *elem, bool sleepable) 
		pool->cleanup(elem);



	if (pool->type == RXE_TYPE_MR)

		kfree(elem->obj);

		kfree_rcu(elem->obj);



	atomic_dec(&pool->num_elem);
@@ -299,12 +295,8 @@ int __rxe_put(struct rxe_pool_elem *elem) 


void __rxe_finalize(struct rxe_pool_elem *elem)

{

	struct xarray *xa = &elem->pool->xa;

	unsigned long flags;

	void *ret;



	xa_lock_irqsave(xa, flags);

	ret = __xa_store(&elem->pool->xa, elem->index, elem, GFP_KERNEL);

	xa_unlock_irqrestore(xa, flags);

	WARN_ON(xa_err(ret));

	void *xa_ret;



	xa_ret = xa_store(&elem->pool->xa, elem->index, elem, GFP_KERNEL);

	WARN_ON(xa_err(xa_ret));

}