Commit 5502e871 authored by Jiri Pirko's avatar Jiri Pirko Committed by Jakub Kicinski
Browse files

net: devlink: remove region snapshot ID tracking dependency on devlink->lock 



After mlx4 driver is converted to do locked reload, functions to get/put
regions snapshot ID may be called from both locked and unlocked context.

So resolve this by removing dependency on devlink->lock for region
snapshot ID tracking by using internal xa_lock() to maintain
shapshot_ids xa_array consistency.

Signed-off-by: default avatarJiri Pirko <jiri@nvidia.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 1515a1b8

net/core/devlink.c

+33 −31
Original line number Diff line number Diff line
@@ -5894,21 +5894,28 @@ static int __devlink_snapshot_id_increment(struct devlink *devlink, u32 id) 
{

	unsigned long count;

	void *p;

	int err;



	devl_assert_locked(devlink);



	xa_lock(&devlink->snapshot_ids);

	p = xa_load(&devlink->snapshot_ids, id);

	if (WARN_ON(!p))

		return -EINVAL;

	if (WARN_ON(!p)) {

		err = -EINVAL;

		goto unlock;

	}



	if (WARN_ON(!xa_is_value(p)))

		return -EINVAL;

	if (WARN_ON(!xa_is_value(p))) {

		err = -EINVAL;

		goto unlock;

	}



	count = xa_to_value(p);

	count++;



	return xa_err(xa_store(&devlink->snapshot_ids, id, xa_mk_value(count),

			       GFP_KERNEL));

	err = xa_err(__xa_store(&devlink->snapshot_ids, id, xa_mk_value(count),

				GFP_ATOMIC));

unlock:

	xa_unlock(&devlink->snapshot_ids);

	return err;

}



/**
@@ -5931,25 +5938,26 @@ static void __devlink_snapshot_id_decrement(struct devlink *devlink, u32 id) 
	unsigned long count;

	void *p;



	devl_assert_locked(devlink);



	xa_lock(&devlink->snapshot_ids);

	p = xa_load(&devlink->snapshot_ids, id);

	if (WARN_ON(!p))

		return;

		goto unlock;



	if (WARN_ON(!xa_is_value(p)))

		return;

		goto unlock;



	count = xa_to_value(p);



	if (count > 1) {

		count--;

		xa_store(&devlink->snapshot_ids, id, xa_mk_value(count),

			 GFP_KERNEL);

		__xa_store(&devlink->snapshot_ids, id, xa_mk_value(count),

			   GFP_ATOMIC);

	} else {

		/* If this was the last user, we can erase this id */

		xa_erase(&devlink->snapshot_ids, id);

		__xa_erase(&devlink->snapshot_ids, id);

	}

unlock:

	xa_unlock(&devlink->snapshot_ids);

}



/**
@@ -5970,13 +5978,17 @@ static void __devlink_snapshot_id_decrement(struct devlink *devlink, u32 id) 
 */

static int __devlink_snapshot_id_insert(struct devlink *devlink, u32 id)

{

	devl_assert_locked(devlink);

	int err;



	if (xa_load(&devlink->snapshot_ids, id))

	xa_lock(&devlink->snapshot_ids);

	if (xa_load(&devlink->snapshot_ids, id)) {

		xa_unlock(&devlink->snapshot_ids);

		return -EEXIST;



	return xa_err(xa_store(&devlink->snapshot_ids, id, xa_mk_value(0),

			       GFP_KERNEL));

	}

	err = xa_err(__xa_store(&devlink->snapshot_ids, id, xa_mk_value(0),

				GFP_ATOMIC));

	xa_unlock(&devlink->snapshot_ids);

	return err;

}



/**
@@ -5997,8 +6009,6 @@ static int __devlink_snapshot_id_insert(struct devlink *devlink, u32 id) 
 */

static int __devlink_region_snapshot_id_get(struct devlink *devlink, u32 *id)

{

	devl_assert_locked(devlink);



	return xa_alloc(&devlink->snapshot_ids, id, xa_mk_value(1),

			xa_limit_32b, GFP_KERNEL);

}
@@ -11442,13 +11452,7 @@ EXPORT_SYMBOL_GPL(devlink_region_destroy); 
 */

int devlink_region_snapshot_id_get(struct devlink *devlink, u32 *id)

{

	int err;



	devl_lock(devlink);

	err = __devlink_region_snapshot_id_get(devlink, id);

	devl_unlock(devlink);



	return err;

	return __devlink_region_snapshot_id_get(devlink, id);

}

EXPORT_SYMBOL_GPL(devlink_region_snapshot_id_get);
@@ -11464,9 +11468,7 @@ EXPORT_SYMBOL_GPL(devlink_region_snapshot_id_get); 
 */

void devlink_region_snapshot_id_put(struct devlink *devlink, u32 id)

{

	devl_lock(devlink);

	__devlink_snapshot_id_decrement(devlink, id);

	devl_unlock(devlink);

}

EXPORT_SYMBOL_GPL(devlink_region_snapshot_id_put);