[PATCH 3/8] drm/amdgpu: introduce userqueue MQD handlers

[Shashank Sharma]

On 07/02/2023 08:11, Christian König wrote:
> Am 03.02.23 um 22:54 schrieb Shashank Sharma:
>> From: Shashank Sharma <contactshashanksharma at gmail.com>
>>
>> A Memory queue descriptor (MQD) of a userqueue defines it in the 
>> harware's
>> context. As the method of formation of a MQD, and its format can vary 
>> between
>> different graphics IPs, we need gfx GEN specific handlers to create 
>> MQDs.
>>
>> This patch:
>> - Introduces MQD hander functions for the usermode queues
>> - A general function to create and destroy MQD for a userqueue.
>>
>> V1: Worked on review comments from Alex on RFC patches:
>>      MQD creation should be gen and IP specific.
>>
>> Cc: Alex Deucher <alexander.deucher at amd.com>
>> Cc: Christian Koenig <christian.koenig at amd.com>
>> Signed-off-by: Shashank Sharma <contactshashanksharma at gmail.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c | 64 +++++++++++++++++++
>>   .../gpu/drm/amd/include/amdgpu_userqueue.h    |  9 +++
>>   2 files changed, 73 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
>> index d5bc7fe81750..625c2fe1e84a 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
>> @@ -42,6 +42,60 @@ static struct amdgpu_usermode_queue
>>       return idr_find(&uq_mgr->userq_idr, qid);
>>   }
>>   +static int
>> +amdgpu_userqueue_create_mqd(struct amdgpu_userq_mgr *uq_mgr, struct 
>> amdgpu_usermode_queue *queue)
>> +{
>> +    int r;
>> +    int size;
>> +    struct amdgpu_device *adev = uq_mgr->adev;
>> +
>> +    if (!uq_mgr->userq_mqd_funcs) {
>> +        DRM_ERROR("Userqueue not initialized\n");
>> +        return -EINVAL;
>> +    }
>> +
>> +    size = uq_mgr->userq_mqd_funcs->mqd_size(uq_mgr);
>> +    r = amdgpu_bo_create_kernel(adev, size, PAGE_SIZE,
>> +                                AMDGPU_GEM_DOMAIN_VRAM,
>> +                                &queue->mqd_obj,
>> +                                &queue->mqd_gpu_addr,
>> +                                &queue->mqd_cpu_ptr);
>
> We can't use amdgpu_bo_create_kernel() here, this pins the BO.
>
> Instead all BOs of the process must be fenced with some eviction fence.


Noted,

- Shashank

>
> Christian.
>
>> +    if (r) {
>> +        DRM_ERROR("Failed to allocate bo for userqueue (%d)", r);
>> +        return r;
>> +    }
>> +
>> +    memset(queue->mqd_cpu_ptr, 0, size);
>> +    r = amdgpu_bo_reserve(queue->mqd_obj, false);
>> +    if (unlikely(r != 0)) {
>> +        DRM_ERROR("Failed to reserve mqd for userqueue (%d)", r);
>> +        goto free_mqd;
>> +    }
>> +
>> +    r = uq_mgr->userq_mqd_funcs->mqd_create(uq_mgr, queue);
>> +    amdgpu_bo_unreserve(queue->mqd_obj);
>> +    if (r) {
>> +        DRM_ERROR("Failed to create MQD for queue\n");
>> +        goto free_mqd;
>> +    }
>> +    return 0;
>> +
>> +free_mqd:
>> +    amdgpu_bo_free_kernel(&queue->mqd_obj,
>> +               &queue->mqd_gpu_addr,
>> +               &queue->mqd_cpu_ptr);
>> +   return r;
>> +}
>> +
>> +static void
>> +amdgpu_userqueue_destroy_mqd(struct amdgpu_userq_mgr *uq_mgr, struct 
>> amdgpu_usermode_queue *queue)
>> +{
>> +    uq_mgr->userq_mqd_funcs->mqd_destroy(uq_mgr, queue);
>> +    amdgpu_bo_free_kernel(&queue->mqd_obj,
>> +               &queue->mqd_gpu_addr,
>> +               &queue->mqd_cpu_ptr);
>> +}
>> +
>>   static int amdgpu_userqueue_create(struct drm_file *filp, union 
>> drm_amdgpu_userq *args)
>>   {
>>       int r, pasid;
>> @@ -82,12 +136,21 @@ static int amdgpu_userqueue_create(struct 
>> drm_file *filp, union drm_amdgpu_userq
>>           goto free_queue;
>>       }
>>   +    r = amdgpu_userqueue_create_mqd(uq_mgr, queue);
>> +    if (r) {
>> +        DRM_ERROR("Failed to create MQD\n");
>> +        goto free_qid;
>> +    }
>> +
>>       list_add_tail(&queue->userq_node, &uq_mgr->userq_list);
>>       args->out.q_id = queue->queue_id;
>>       args->out.flags = 0;
>>       mutex_unlock(&uq_mgr->userq_mutex);
>>       return 0;
>>   +free_qid:
>> +    amdgpu_userqueue_free_index(uq_mgr, queue->queue_id);
>> +
>>   free_queue:
>>       mutex_unlock(&uq_mgr->userq_mutex);
>>       kfree(queue);
>> @@ -107,6 +170,7 @@ static void amdgpu_userqueue_destroy(struct 
>> drm_file *filp, int queue_id)
>>       }
>>         mutex_lock(&uq_mgr->userq_mutex);
>> +    amdgpu_userqueue_destroy_mqd(uq_mgr, queue);
>>       amdgpu_userqueue_free_index(uq_mgr, queue->queue_id);
>>       list_del(&queue->userq_node);
>>       mutex_unlock(&uq_mgr->userq_mutex);
>> diff --git a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h 
>> b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
>> index 9557588fe34f..a6abdfd5cb74 100644
>> --- a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
>> +++ b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
>> @@ -26,10 +26,13 @@
>>     #define AMDGPU_MAX_USERQ 512
>>   +struct amdgpu_userq_mqd_funcs;
>> +
>>   struct amdgpu_userq_mgr {
>>       struct idr userq_idr;
>>       struct mutex userq_mutex;
>>       struct list_head userq_list;
>> +    const struct amdgpu_userq_mqd_funcs *userq_mqd_funcs;
>>       struct amdgpu_device *adev;
>>   };
>>   @@ -57,6 +60,12 @@ struct amdgpu_usermode_queue {
>>     int amdgpu_userq_ioctl(struct drm_device *dev, void *data, struct 
>> drm_file *filp);
>>   +struct amdgpu_userq_mqd_funcs {
>> +    int (*mqd_size)(struct amdgpu_userq_mgr *);
>> +    int (*mqd_create)(struct amdgpu_userq_mgr *, struct 
>> amdgpu_usermode_queue *);
>> +    void (*mqd_destroy)(struct amdgpu_userq_mgr *, struct 
>> amdgpu_usermode_queue *);
>> +};
>> +
>>   int amdgpu_userq_mgr_init(struct amdgpu_userq_mgr *userq_mgr, 
>> struct amdgpu_device *adev);
>>     void amdgpu_userq_mgr_fini(struct amdgpu_userq_mgr *userq_mgr);
>