dma-buf/dma-fence: remove unnecessary callbacks

The fence_value_str and timeline_value_str callbacks were just an
unnecessary abstraction in the SW sync implementation.

The only caller of those callbacks already knew that the fence in
questions is a timeline_fence. So print the values directly instead
of using a redirection.

Additional to that remove the implementations from virtgpu and vgem.
As far as I can see those were never used in the first place.

Signed-off-by: Christian König <[e-mail]>
Reviewed-by: Simona Vetter <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/dma-buf/sw_sync.c

···
 	return !__dma_fence_is_later(fence->seqno, parent->value, fence->ops);
 }
 
-static void timeline_fence_value_str(struct dma_fence *fence,
-				    char *str, int size)
-{
-	snprintf(str, size, "%lld", fence->seqno);
-}
-
-static void timeline_fence_timeline_value_str(struct dma_fence *fence,
-					     char *str, int size)
-{
-	struct sync_timeline *parent = dma_fence_parent(fence);
-
-	snprintf(str, size, "%d", parent->value);
-}
-
 static void timeline_fence_set_deadline(struct dma_fence *fence, ktime_t deadline)
 {
 	struct sync_pt *pt = dma_fence_to_sync_pt(fence);
···
 	.get_timeline_name = timeline_fence_get_timeline_name,
 	.signaled = timeline_fence_signaled,
 	.release = timeline_fence_release,
-	.fence_value_str = timeline_fence_value_str,
-	.timeline_value_str = timeline_fence_timeline_value_str,
 	.set_deadline = timeline_fence_set_deadline,
 };
 

drivers/dma-buf/sync_debug.c

···
 		seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
 	}
 
-	if (fence->ops->timeline_value_str &&
-		fence->ops->fence_value_str) {
-		char value[64];
-		bool success;
-
-		fence->ops->fence_value_str(fence, value, sizeof(value));
-		success = strlen(value);
-
-		if (success) {
-			seq_printf(s, ": %s", value);
-
-			fence->ops->timeline_value_str(fence, value,
-						       sizeof(value));
-
-			if (strlen(value))
-				seq_printf(s, " / %s", value);
-		}
-	}
-
+	seq_printf(s, ": %lld", fence->seqno);
+	seq_printf(s, " / %d", parent->value);
 	seq_putc(s, '\n');
 }
 

drivers/gpu/drm/vgem/vgem_fence.c

···
 	dma_fence_free(&fence->base);
 }
 
-static void vgem_fence_value_str(struct dma_fence *fence, char *str, int size)
-{
-	snprintf(str, size, "%llu", fence->seqno);
-}
-
-static void vgem_fence_timeline_value_str(struct dma_fence *fence, char *str,
-					  int size)
-{
-	snprintf(str, size, "%llu",
-		 dma_fence_is_signaled(fence) ? fence->seqno : 0);
-}
-
 static const struct dma_fence_ops vgem_fence_ops = {
 	.get_driver_name = vgem_fence_get_driver_name,
 	.get_timeline_name = vgem_fence_get_timeline_name,
 	.release = vgem_fence_release,
-
-	.fence_value_str = vgem_fence_value_str,
-	.timeline_value_str = vgem_fence_timeline_value_str,
 };
 
 static void vgem_fence_timeout(struct timer_list *t)

drivers/gpu/drm/virtio/virtgpu_fence.c

···
 	return false;
 }
 
-static void virtio_gpu_fence_value_str(struct dma_fence *f, char *str, int size)
-{
-	snprintf(str, size, "[%llu, %llu]", f->context, f->seqno);
-}
-
-static void virtio_gpu_timeline_value_str(struct dma_fence *f, char *str,
-					  int size)
-{
-	struct virtio_gpu_fence *fence = to_virtio_gpu_fence(f);
-
-	snprintf(str, size, "%llu",
-		 (u64)atomic64_read(&fence->drv->last_fence_id));
-}
-
 static const struct dma_fence_ops virtio_gpu_fence_ops = {
 	.get_driver_name     = virtio_gpu_get_driver_name,
 	.get_timeline_name   = virtio_gpu_get_timeline_name,
 	.signaled            = virtio_gpu_fence_signaled,
-	.fence_value_str     = virtio_gpu_fence_value_str,
-	.timeline_value_str  = virtio_gpu_timeline_value_str,
 };
 
 struct virtio_gpu_fence *virtio_gpu_fence_alloc(struct virtio_gpu_device *vgdev,

include/linux/dma-fence.h

···
 	void (*release)(struct dma_fence *fence);
 
 	/**
-	 * @fence_value_str:
-	 *
-	 * Callback to fill in free-form debug info specific to this fence, like
-	 * the sequence number.
-	 *
-	 * This callback is optional.
-	 */
-	void (*fence_value_str)(struct dma_fence *fence, char *str, int size);
-
-	/**
-	 * @timeline_value_str:
-	 *
-	 * Fills in the current value of the timeline as a string, like the
-	 * sequence number. Note that the specific fence passed to this function
-	 * should not matter, drivers should only use it to look up the
-	 * corresponding timeline structures.
-	 */
-	void (*timeline_value_str)(struct dma_fence *fence,
-				   char *str, int size);
-
-	/**
 	 * @set_deadline:
 	 *
 	 * Callback to allow a fence waiter to inform the fence signaler of