[PATCH V3 10/13] amdkfd: process pointer of a HIQ should be set to NULL

[Felix Kuehling]

On 2025-08-04 7:05, Zhu Lingshan wrote:
> In kq_initialize, queue->process of a HIQ should
> be set to NULL because it does not belong to any kfd_process.
>
> This commit decommisions the function kfd_get_process() because
> it can not locate a specific kfd_process among multiple
> contexts and not any code path calls it after this commit.
>
> Signed-off-by: Zhu Lingshan <lingshan.zhu at amd.com>
> ---
>  drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c |  3 ++-
>  drivers/gpu/drm/amd/amdkfd/kfd_priv.h         |  1 -
>  drivers/gpu/drm/amd/amdkfd/kfd_process.c      | 18 ------------------
>  3 files changed, 2 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c b/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c
> index 2b0a830f5b29..ebee37937783 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c
> @@ -144,7 +144,8 @@ static bool kq_initialize(struct kernel_queue *kq, struct kfd_node *dev,
>  		goto err_init_queue;
>  
>  	kq->queue->device = dev;
> -	kq->queue->process = kfd_get_process(current);
> +	if (type == KFD_QUEUE_TYPE_HIQ)
> +		kq->queue->process = NULL;

I think this should either unconditionally set the process to NULL for kernel queues, or not touch it at all, because it's probably 0-initialized at allocation time.

Either way, this commit should come after the one that removes the DIQ type, because DIQ did belong to a process.

Regards,
  Felix


>  
>  	kq->queue->mqd_mem_obj = kq->mqd_mgr->allocate_mqd(kq->mqd_mgr->dev,
>  					&kq->queue->properties);
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
> index d140463e221b..25534473c28f 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
> @@ -1050,7 +1050,6 @@ void kfd_process_destroy_wq(void);
>  void kfd_cleanup_processes(void);
>  struct kfd_process *kfd_create_process(struct task_struct *thread);
>  int kfd_create_process_sysfs(struct kfd_process *process);
> -struct kfd_process *kfd_get_process(const struct task_struct *task);
>  struct kfd_process *kfd_lookup_process_by_pasid(u32 pasid,
>  						 struct kfd_process_device **pdd);
>  struct kfd_process *kfd_lookup_process_by_mm(const struct mm_struct *mm);
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process.c b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> index 8e498fd35b8c..0c3f0cc16bf4 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> @@ -989,24 +989,6 @@ struct kfd_process *kfd_create_process(struct task_struct *thread)
>  	return process;
>  }
>  
> -struct kfd_process *kfd_get_process(const struct task_struct *thread)
> -{
> -	struct kfd_process *process;
> -
> -	if (!thread->mm)
> -		return ERR_PTR(-EINVAL);
> -
> -	/* Only the pthreads threading model is supported. */
> -	if (thread->group_leader->mm != thread->mm)
> -		return ERR_PTR(-EINVAL);
> -
> -	process = find_process(thread, false);
> -	if (!process)
> -		return ERR_PTR(-EINVAL);
> -
> -	return process;
> -}
> -
>  static struct kfd_process *find_process_by_mm(const struct mm_struct *mm)
>  {
>  	struct kfd_process *process;