[RFC PATCH 7/8] drm/virtio: check context when signaling

[Gurchetan Singh]

This change:
	- Lookups virtgpu_fence given a fence_id
	- Signals all prior fences in a given context
	- Signals current fence

No functional changes yet, since all fences are initialized from
context 0.

Signed-off-by: Gurchetan Singh <gurchetansingh at chromium.org>
---
 drivers/gpu/drm/virtio/virtgpu_fence.c | 27 ++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_fence.c b/drivers/gpu/drm/virtio/virtgpu_fence.c
index a63a383347c4..a6c6f498e79e 100644
--- a/drivers/gpu/drm/virtio/virtgpu_fence.c
+++ b/drivers/gpu/drm/virtio/virtgpu_fence.c
@@ -115,17 +115,32 @@ void virtio_gpu_fence_event_process(struct virtio_gpu_device *vgdev,
 				    u64 fence_id)
 {
 	struct virtio_gpu_fence_driver *drv = &vgdev->fence_drv;
-	struct virtio_gpu_fence *fence, *tmp;
+	struct virtio_gpu_fence *signaled, *curr, *tmp;
 	unsigned long irq_flags;
 
 	spin_lock_irqsave(&drv->lock, irq_flags);
 	atomic64_set(&vgdev->fence_drv.last_fence_id, fence_id);
-	list_for_each_entry_safe(fence, tmp, &drv->fences, node) {
-		if (fence_id < fence->f.seqno)
+	list_for_each_entry_safe(curr, tmp, &drv->fences, node) {
+		if (fence_id != curr->fence_id)
 			continue;
-		dma_fence_signal_locked(&fence->f);
-		list_del(&fence->node);
-		dma_fence_put(&fence->f);
+
+		signaled = curr;
+		list_for_each_entry_safe(curr, tmp, &drv->fences, node) {
+			if (signaled->f.context != curr->f.context)
+				continue;
+
+			if (!dma_fence_is_later(&signaled->f, &curr->f))
+				continue;
+
+			dma_fence_signal_locked(&curr->f);
+			list_del(&curr->node);
+			dma_fence_put(&curr->f);
+		}
+
+		dma_fence_signal_locked(&signaled->f);
+		list_del(&signaled->node);
+		dma_fence_put(&signaled->f);
+		break;
 	}
 	spin_unlock_irqrestore(&drv->lock, irq_flags);
 }
-- 
2.25.1.481.gfbce0eb801-goog