[PATCH 1/4] Revert "drm/amdkfd: Fix sdma queue allocate race condition"

[Yang, Philip]

I just figured out previous patch have issue. New patch is simple and 
looks good to me.

This series is Reviewed-by: Philip.Yang <philip.yang at amd.com>

On 2019-06-14 9:27 p.m., Zeng, Oak wrote:
> This reverts commit 0a7c7281bdaae8cf63d77be26a4b46128114bdec.
> This fix is not proper. allocate_mqd can't be moved before
> allocate_sdma_queue as it depends on q->properties->sdma_id
> set in later.
> 
> Change-Id: If4934afebda8cf37dfcde9b50ce53643d526584d
> Signed-off-by: Oak Zeng <Oak.Zeng at amd.com>
> ---
>   .../gpu/drm/amd/amdkfd/kfd_device_queue_manager.c  | 26 ++++++++++++----------
>   1 file changed, 14 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
> index 250798b..d566c26 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
> @@ -1133,27 +1133,23 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
>   	if (dqm->total_queue_count >= max_num_of_queues_per_device) {
>   		pr_warn("Can't create new usermode queue because %d queues were already created\n",
>   				dqm->total_queue_count);
> -		return -EPERM;
> +		retval = -EPERM;
> +		goto out;
>   	}
>   
> -	mqd_mgr = dqm->mqd_mgrs[get_mqd_type_from_queue_type(
> -			q->properties.type)];
> -	q->mqd_mem_obj = mqd_mgr->allocate_mqd(mqd_mgr->dev, &q->properties);
> -	if (!q->mqd_mem_obj)
> -		return -ENOMEM;
> -
> -	dqm_lock(dqm);
>   	if (q->properties.type == KFD_QUEUE_TYPE_SDMA ||
>   		q->properties.type == KFD_QUEUE_TYPE_SDMA_XGMI) {
>   		retval = allocate_sdma_queue(dqm, q);
>   		if (retval)
> -			goto out_unlock;
> +			goto out;
>   	}
>   
>   	retval = allocate_doorbell(qpd, q);
>   	if (retval)
>   		goto out_deallocate_sdma_queue;
>   
> +	mqd_mgr = dqm->mqd_mgrs[get_mqd_type_from_queue_type(
> +			q->properties.type)];
>   	/*
>   	 * Eviction state logic: mark all queues as evicted, even ones
>   	 * not currently active. Restoring inactive queues later only
> @@ -1165,8 +1161,14 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
>   		dqm->asic_ops.init_sdma_vm(dqm, q, qpd);
>   	q->properties.tba_addr = qpd->tba_addr;
>   	q->properties.tma_addr = qpd->tma_addr;
> +	q->mqd_mem_obj = mqd_mgr->allocate_mqd(mqd_mgr->dev, &q->properties);
> +	if (!q->mqd_mem_obj) {
> +		retval = -ENOMEM;
> +		goto out_deallocate_doorbell;
> +	}
>   	mqd_mgr->init_mqd(mqd_mgr, &q->mqd, q->mqd_mem_obj,
>   				&q->gart_mqd_addr, &q->properties);
> +	dqm_lock(dqm);
>   
>   	list_add(&q->list, &qpd->queues_list);
>   	qpd->queue_count++;
> @@ -1192,13 +1194,13 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
>   	dqm_unlock(dqm);
>   	return retval;
>   
> +out_deallocate_doorbell:
> +	deallocate_doorbell(qpd, q);
>   out_deallocate_sdma_queue:
>   	if (q->properties.type == KFD_QUEUE_TYPE_SDMA ||
>   		q->properties.type == KFD_QUEUE_TYPE_SDMA_XGMI)
>   		deallocate_sdma_queue(dqm, q);
> -out_unlock:
> -	dqm_unlock(dqm);
> -	mqd_mgr->free_mqd(mqd_mgr, q->mqd, q->mqd_mem_obj);
> +out:
>   	return retval;
>   }
>   
>