[PATCH v9 09/18] drm/virtio: rework virtio_gpu_object_create fencing

From: Gerd Hoffmann
Date: Thu Aug 29 2019 - 06:33:28 EST


Rework fencing workflow. Stop using ttm helpers, use the
virtio_gpu_array_* helpers instead.

Due to using the gem reservation object it is initialized and ready for
use before calling ttm_bo_init. So we can simply use the standard
fencing workflow and drop the tricky logic which checks whenever the
command is in flight still.

v6: rewrite most of the patch.

Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
---
drivers/gpu/drm/virtio/virtgpu_drv.h | 2 +
drivers/gpu/drm/virtio/virtgpu_object.c | 74 +++++++++++--------------
drivers/gpu/drm/virtio/virtgpu_vq.c | 4 ++
3 files changed, 37 insertions(+), 43 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index f4f843aec18a..c6ea65f6507e 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -274,6 +274,7 @@ void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev);
void virtio_gpu_cmd_create_resource(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object *bo,
struct virtio_gpu_object_params *params,
+ struct virtio_gpu_object_array *objs,
struct virtio_gpu_fence *fence);
void virtio_gpu_cmd_unref_resource(struct virtio_gpu_device *vgdev,
uint32_t resource_id);
@@ -336,6 +337,7 @@ void
virtio_gpu_cmd_resource_create_3d(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object *bo,
struct virtio_gpu_object_params *params,
+ struct virtio_gpu_object_array *objs,
struct virtio_gpu_fence *fence);
void virtio_gpu_ctrl_ack(struct virtqueue *vq);
void virtio_gpu_cursor_ack(struct virtqueue *vq);
diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c
index ad216d062507..6af2862c9a73 100644
--- a/drivers/gpu/drm/virtio/virtgpu_object.c
+++ b/drivers/gpu/drm/virtio/virtgpu_object.c
@@ -103,6 +103,7 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object **bo_ptr,
struct virtio_gpu_fence *fence)
{
+ struct virtio_gpu_object_array *objs = NULL;
struct virtio_gpu_object *bo;
size_t acc_size;
int ret;
@@ -116,23 +117,34 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
if (bo == NULL)
return -ENOMEM;
ret = virtio_gpu_resource_id_get(vgdev, &bo->hw_res_handle);
- if (ret < 0) {
- kfree(bo);
- return ret;
- }
+ if (ret < 0)
+ goto err_free_gem;
+
params->size = roundup(params->size, PAGE_SIZE);
ret = drm_gem_object_init(vgdev->ddev, &bo->gem_base, params->size);
- if (ret != 0) {
- virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
- kfree(bo);
- return ret;
- }
+ if (ret != 0)
+ goto err_put_id;
+
bo->dumb = params->dumb;

+ if (fence) {
+ ret = -ENOMEM;
+ objs = virtio_gpu_array_alloc(1);
+ if (!objs)
+ goto err_put_id;
+ virtio_gpu_array_add_obj(objs, &bo->gem_base);
+
+ ret = virtio_gpu_array_lock_resv(objs);
+ if (ret != 0)
+ goto err_put_objs;
+ }
+
if (params->virgl) {
- virtio_gpu_cmd_resource_create_3d(vgdev, bo, params, fence);
+ virtio_gpu_cmd_resource_create_3d(vgdev, bo, params,
+ objs, fence);
} else {
- virtio_gpu_cmd_create_resource(vgdev, bo, params, fence);
+ virtio_gpu_cmd_create_resource(vgdev, bo, params,
+ objs, fence);
}

virtio_gpu_init_ttm_placement(bo);
@@ -145,40 +157,16 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
if (ret != 0)
return ret;

- if (fence) {
- struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
- struct list_head validate_list;
- struct ttm_validate_buffer mainbuf;
- struct ww_acquire_ctx ticket;
- unsigned long irq_flags;
- bool signaled;
-
- INIT_LIST_HEAD(&validate_list);
- memset(&mainbuf, 0, sizeof(struct ttm_validate_buffer));
-
- /* use a gem reference since unref list undoes them */
- drm_gem_object_get(&bo->gem_base);
- mainbuf.bo = &bo->tbo;
- list_add(&mainbuf.head, &validate_list);
-
- ret = virtio_gpu_object_list_validate(&ticket, &validate_list);
- if (ret == 0) {
- spin_lock_irqsave(&drv->lock, irq_flags);
- signaled = virtio_fence_signaled(&fence->f);
- if (!signaled)
- /* virtio create command still in flight */
- ttm_eu_fence_buffer_objects(&ticket, &validate_list,
- &fence->f);
- spin_unlock_irqrestore(&drv->lock, irq_flags);
- if (signaled)
- /* virtio create command finished */
- ttm_eu_backoff_reservation(&ticket, &validate_list);
- }
- virtio_gpu_unref_list(&validate_list);
- }
-
*bo_ptr = bo;
return 0;
+
+err_put_objs:
+ virtio_gpu_array_put_free(objs);
+err_put_id:
+ virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
+err_free_gem:
+ kfree(bo);
+ return ret;
}

void virtio_gpu_object_kunmap(struct virtio_gpu_object *bo)
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 5137dcf11d31..7509424a7b92 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -396,6 +396,7 @@ static void virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev,
void virtio_gpu_cmd_create_resource(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object *bo,
struct virtio_gpu_object_params *params,
+ struct virtio_gpu_object_array *objs,
struct virtio_gpu_fence *fence)
{
struct virtio_gpu_resource_create_2d *cmd_p;
@@ -403,6 +404,7 @@ void virtio_gpu_cmd_create_resource(struct virtio_gpu_device *vgdev,

cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
memset(cmd_p, 0, sizeof(*cmd_p));
+ vbuf->objs = objs;

cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_CREATE_2D);
cmd_p->resource_id = cpu_to_le32(bo->hw_res_handle);
@@ -869,6 +871,7 @@ void
virtio_gpu_cmd_resource_create_3d(struct virtio_gpu_device *vgdev,
struct virtio_gpu_object *bo,
struct virtio_gpu_object_params *params,
+ struct virtio_gpu_object_array *objs,
struct virtio_gpu_fence *fence)
{
struct virtio_gpu_resource_create_3d *cmd_p;
@@ -876,6 +879,7 @@ virtio_gpu_cmd_resource_create_3d(struct virtio_gpu_device *vgdev,

cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
memset(cmd_p, 0, sizeof(*cmd_p));
+ vbuf->objs = objs;

cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_CREATE_3D);
cmd_p->resource_id = cpu_to_le32(bo->hw_res_handle);
--
2.18.1