[PATCH 26/49] req-selftest-cancel

[Chris Wilson]

---
 drivers/gpu/drm/i915/i915_gem_request.c | 89 +++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
index afcca49a8f04..d2d2eea53249 100644
--- a/drivers/gpu/drm/i915/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/i915_gem_request.c
@@ -1354,6 +1354,24 @@ mock_request(struct intel_engine_cs *engine,
 	return &mock->base;
 }
 
+static bool mock_cancel_request(struct drm_i915_gem_request *request)
+{
+	struct mock_request *mock = container_of(request, typeof(*mock), base);
+	struct mock_engine *engine =
+		container_of(request->engine, typeof(*engine), base);
+	bool was_queued;
+
+	spin_lock_irq(&engine->hw_lock);
+	was_queued = !list_empty(&mock->link);
+	list_del_init(&mock->link);
+	spin_unlock_irq(&engine->hw_lock);
+
+	if (was_queued)
+		i915_gem_request_unsubmit(request);
+
+	return was_queued;
+}
+
 static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
 {
 	struct intel_ring *ring;
@@ -1493,6 +1511,12 @@ mock_context(struct drm_i915_private *i915,
 	return ctx;
 }
 
+static void mock_context_close(struct i915_gem_context *ctx)
+{
+	ctx->closed = true;
+	i915_gem_context_put(ctx);
+}
+
 static void mock_retire_work_handler(struct work_struct *work)
 {
 }
@@ -1717,12 +1741,77 @@ static int igt_fence_wait(void *ignore)
 	return err;
 }
 
+static int igt_request_rewind(void *ignore)
+{
+	struct drm_i915_private *i915;
+	struct drm_i915_gem_request *request, *vip;
+	struct i915_gem_context *ctx[2];
+	int err = -ENOMEM;
+
+	i915 = mock_device();
+	if (!i915)
+		goto out;
+
+	err = -EINVAL;
+	mutex_lock(&i915->drm.struct_mutex);
+	ctx[0] = mock_context(i915, "A");
+	request = mock_request(i915->engine[RCS], ctx[0], 2 * HZ);
+	if (!request) {
+		err = -ENOMEM;
+		mutex_unlock(&i915->drm.struct_mutex);
+		goto out_device;
+	}
+	i915_add_request(request);
+
+	ctx[1] = mock_context(i915, "B");
+	vip = mock_request(i915->engine[RCS], ctx[1], 0);
+	if (!vip) {
+		err = -ENOMEM;
+		mutex_unlock(&i915->drm.struct_mutex);
+		goto err;
+	}
+
+	/* Simulate preemption by manual reordering */
+	if (!mock_cancel_request(request)) {
+		pr_err("failed to cancel request (already executed)!\n");
+		i915_add_request(vip);
+		goto err;
+	}
+	i915_add_request(vip);
+	mock_submit_request(request);
+
+	mutex_unlock(&i915->drm.struct_mutex);
+
+	if (i915_wait_request(vip, 0, HZ) == -ETIME) {
+		pr_err("timed out waiting for high priority request, vip.seqno=%d, current seqno=%d\n",
+		       vip->global_seqno, intel_engine_get_seqno(i915->engine[RCS]));
+		goto err;
+	}
+
+	if (i915_gem_request_completed(request)) {
+		pr_err("low priority request already completed\n");
+		goto err;
+	}
+
+	err = 0;
+err:
+	mutex_lock(&i915->drm.struct_mutex);
+	mock_context_close(ctx[1]);
+	mock_context_close(ctx[0]);
+	mutex_unlock(&i915->drm.struct_mutex);
+out_device:
+	mock_device_free(i915);
+out:
+	return err;
+}
+
 int i915_gem_request_selftest(void)
 {
 	static const struct i915_subtest tests[] = {
 		SUBTEST(igt_add_request),
 		SUBTEST(igt_wait_request),
 		SUBTEST(igt_fence_wait),
+		SUBTEST(igt_request_rewind),
 	};
 
 	return i915_subtests(tests, NULL);
-- 
2.11.0