drm/amdgpu: remove the exclusive lock

Finally getting rid of it.
Signed-off-by: Christian König <christian.koenig@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -1955,7 +1955,6 @@ struct amdgpu_device {
 	struct device			*dev;
 	struct drm_device		*ddev;
 	struct pci_dev			*pdev;
-	struct rw_semaphore		exclusive_lock;
 
 	/* ASIC */
 	enum amd_asic_type		asic_type;

drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c

@@ -831,11 +831,8 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	bool reserved_buffers = false;
 	int i, r;
 
-	down_read(&adev->exclusive_lock);
-	if (!adev->accel_working) {
-		up_read(&adev->exclusive_lock);
+	if (!adev->accel_working)
 		return -EBUSY;
-	}
 
 	parser = amdgpu_cs_parser_create(adev, filp, NULL, NULL, 0);
 	if (!parser)
@@ -843,8 +840,7 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	r = amdgpu_cs_parser_init(parser, data);
 	if (r) {
 		DRM_ERROR("Failed to initialize parser !\n");
-		kfree(parser);
-		up_read(&adev->exclusive_lock);
+		amdgpu_cs_parser_fini(parser, r, false);
 		r = amdgpu_cs_handle_lockup(adev, r);
 		return r;
 	}
@@ -915,14 +911,12 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 
 		mutex_unlock(&job->job_lock);
 		amdgpu_cs_parser_fini_late(parser);
-		up_read(&adev->exclusive_lock);
 		return 0;
 	}
 
 	cs->out.handle = parser->ibs[parser->num_ibs - 1].sequence;
 out:
 	amdgpu_cs_parser_fini(parser, r, reserved_buffers);
-	up_read(&adev->exclusive_lock);
 	r = amdgpu_cs_handle_lockup(adev, r);
 	return r;
 }

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -1418,7 +1418,6 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	mutex_init(&adev->gfx.gpu_clock_mutex);
 	mutex_init(&adev->srbm_mutex);
 	mutex_init(&adev->grbm_idx_mutex);
-	init_rwsem(&adev->exclusive_lock);
 	mutex_init(&adev->mn_lock);
 	hash_init(adev->mn_hash);
 
@@ -1814,8 +1813,6 @@ int amdgpu_gpu_reset(struct amdgpu_device *adev)
 	int i, r;
 	int resched;
 
-	down_write(&adev->exclusive_lock);
-
 	atomic_inc(&adev->gpu_reset_counter);
 
 	/* block TTM */
@@ -1879,7 +1876,6 @@ int amdgpu_gpu_reset(struct amdgpu_device *adev)
 		dev_info(adev->dev, "GPU reset failed\n");
 	}
 
-	up_write(&adev->exclusive_lock);
 	return r;
 }
 

drivers/gpu/drm/amd/amdgpu/amdgpu_display.c

@@ -47,11 +47,8 @@ static void amdgpu_flip_wait_fence(struct amdgpu_device *adev,
 	fence = to_amdgpu_fence(*f);
 	if (fence) {
 		r = fence_wait(&fence->base, false);
-		if (r == -EDEADLK) {
-			up_read(&adev->exclusive_lock);
+		if (r == -EDEADLK)
 			r = amdgpu_gpu_reset(adev);
-			down_read(&adev->exclusive_lock);
-		}
 	} else
 		r = fence_wait(*f, false);
 
@@ -77,7 +74,6 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
 	unsigned long flags;
 	unsigned i;
 
-	down_read(&adev->exclusive_lock);
 	amdgpu_flip_wait_fence(adev, &work->excl);
 	for (i = 0; i < work->shared_count; ++i)
 		amdgpu_flip_wait_fence(adev, &work->shared[i]);
@@ -93,7 +89,6 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
 	amdgpuCrtc->pflip_status = AMDGPU_FLIP_SUBMITTED;
 
 	spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
-	up_read(&adev->exclusive_lock);
 }
 
 /*

drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c

@@ -260,16 +260,8 @@ static void amdgpu_fence_check_lockup(struct work_struct *work)
 				lockup_work.work);
 	ring = fence_drv->ring;
 
-	if (!down_read_trylock(&ring->adev->exclusive_lock)) {
-		/* just reschedule the check if a reset is going on */
-		amdgpu_fence_schedule_check(ring);
-		return;
-	}
-
-	if (amdgpu_fence_activity(ring)) {
+	if (amdgpu_fence_activity(ring))
 		wake_up_all(&ring->fence_drv.fence_queue);
-	}
-	up_read(&ring->adev->exclusive_lock);
 }
 
 /**
@@ -317,18 +309,15 @@ static bool amdgpu_fence_is_signaled(struct fence *f)
 {
 	struct amdgpu_fence *fence = to_amdgpu_fence(f);
 	struct amdgpu_ring *ring = fence->ring;
-	struct amdgpu_device *adev = ring->adev;
 
 	if (atomic64_read(&ring->fence_drv.last_seq) >= fence->seq)
 		return true;
 
-	if (down_read_trylock(&adev->exclusive_lock)) {
-		amdgpu_fence_process(ring);
-		up_read(&adev->exclusive_lock);
+	amdgpu_fence_process(ring);
+
+	if (atomic64_read(&ring->fence_drv.last_seq) >= fence->seq)
+		return true;
 
-		if (atomic64_read(&ring->fence_drv.last_seq) >= fence->seq)
-			return true;
-	}
 	return false;
 }
 

drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c

@@ -181,7 +181,6 @@ int amdgpu_gem_create_ioctl(struct drm_device *dev, void *data,
 	bool kernel = false;
 	int r;
 
-	down_read(&adev->exclusive_lock);
 	/* create a gem object to contain this object in */
 	if (args->in.domains & (AMDGPU_GEM_DOMAIN_GDS |
 	    AMDGPU_GEM_DOMAIN_GWS | AMDGPU_GEM_DOMAIN_OA)) {
@@ -214,11 +213,9 @@ int amdgpu_gem_create_ioctl(struct drm_device *dev, void *data,
 
 	memset(args, 0, sizeof(*args));
 	args->out.handle = handle;
-	up_read(&adev->exclusive_lock);
 	return 0;
 
 error_unlock:
-	up_read(&adev->exclusive_lock);
 	r = amdgpu_gem_handle_lockup(adev, r);
 	return r;
 }
@@ -250,8 +247,6 @@ int amdgpu_gem_userptr_ioctl(struct drm_device *dev, void *data,
 		return -EACCES;
 	}
 
-	down_read(&adev->exclusive_lock);
-
 	/* create a gem object to contain this object in */
 	r = amdgpu_gem_object_create(adev, args->size, 0,
 				     AMDGPU_GEM_DOMAIN_CPU, 0,
@@ -293,14 +288,12 @@ int amdgpu_gem_userptr_ioctl(struct drm_device *dev, void *data,
 		goto handle_lockup;
 
 	args->handle = handle;
-	up_read(&adev->exclusive_lock);
 	return 0;
 
 release_object:
 	drm_gem_object_unreference_unlocked(gobj);
 
 handle_lockup:
-	up_read(&adev->exclusive_lock);
 	r = amdgpu_gem_handle_lockup(adev, r);
 
 	return r;