[PATCH v11 24/28] drm/amdgpu: resume gfx userqueues

[Shashank Sharma]

This patch adds support for userqueue resume. What it typically does is
this:
- adds a new delayed work for resuming all the queues.
- schedules this delayed work from the suspend work.
- validates the BOs and replaces the eviction fence before resuming all
  the queues running under this instance of userq manager.

V2: Addressed Christian's review comments:
    - declare local variables like ret at the bottom.
    - lock all the object first, then start attaching the new fence.
    - dont replace old eviction fence, just attach new eviction fence.
    - no error logs for drm_exec_lock failures
    - no need to reserve bos after drm_exec_locked
    - schedule the resume worker immediately (not after 100 ms)
    - check for NULL BO (Arvind)

Cc: Alex Deucher <alexander.deucher at amd.com>
Cc: Christian Koenig <christian.koenig at amd.com>
Signed-off-by: Shashank Sharma <shashank.sharma at amd.com>
Signed-off-by: Arvind Yadav <arvind.yadav at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c | 120 ++++++++++++++++++
 .../gpu/drm/amd/include/amdgpu_userqueue.h    |   1 +
 2 files changed, 121 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
index 979174f80993..e7f7354e0c0e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
@@ -405,6 +405,122 @@ int amdgpu_userq_ioctl(struct drm_device *dev, void *data,
 	return r;
 }
 
+static int
+amdgpu_userqueue_resume_all(struct amdgpu_userq_mgr *uq_mgr)
+{
+	struct amdgpu_device *adev = uq_mgr->adev;
+	const struct amdgpu_userq_funcs *userq_funcs;
+	struct amdgpu_usermode_queue *queue;
+	int queue_id, ret;
+
+	userq_funcs = adev->userq_funcs[AMDGPU_HW_IP_GFX];
+
+	/* Resume all the queues for this process */
+	idr_for_each_entry(&uq_mgr->userq_idr, queue, queue_id) {
+		ret = userq_funcs->resume(uq_mgr, queue);
+		if (ret)
+			DRM_ERROR("Failed to resume queue %d\n", queue_id);
+	}
+
+	return ret;
+}
+
+static int
+amdgpu_userqueue_validate_bos(struct amdgpu_userq_mgr *uq_mgr)
+{
+	struct amdgpu_fpriv *fpriv = uq_mgr_to_fpriv(uq_mgr);
+	struct amdgpu_vm *vm = &fpriv->vm;
+	struct amdgpu_bo_va *bo_va, *tmp;
+	struct drm_exec exec;
+	struct amdgpu_bo *bo;
+	int ret;
+
+	drm_exec_init(&exec, DRM_EXEC_IGNORE_DUPLICATES, 0);
+	drm_exec_until_all_locked(&exec) {
+		ret = amdgpu_vm_lock_pd(vm, &exec, 2);
+		drm_exec_retry_on_contention(&exec);
+		if (unlikely(ret)) {
+			DRM_ERROR("Failed to lock PD\n");
+			goto unlock_all;
+		}
+
+		/* Lock the done list */
+		list_for_each_entry_safe(bo_va, tmp, &vm->done, base.vm_status) {
+			bo = bo_va->base.bo;
+			if (!bo)
+				continue;
+
+			ret = drm_exec_lock_obj(&exec, &bo->tbo.base);
+			drm_exec_retry_on_contention(&exec);
+			if (unlikely(ret))
+				goto unlock_all;
+		}
+
+		/* Lock the invalidated list */
+		list_for_each_entry_safe(bo_va, tmp, &vm->invalidated, base.vm_status) {
+			bo = bo_va->base.bo;
+			if (!bo)
+				continue;
+
+			ret = drm_exec_lock_obj(&exec, &bo->tbo.base);
+			drm_exec_retry_on_contention(&exec);
+			if (unlikely(ret))
+				goto unlock_all;
+		}
+	}
+
+	/* Now validate BOs */
+	list_for_each_entry_safe(bo_va, tmp, &vm->invalidated, base.vm_status) {
+		bo = bo_va->base.bo;
+		if (!bo)
+			continue;
+
+		ret = amdgpu_userqueue_validate_vm_bo(NULL, bo);
+		if (ret) {
+			DRM_ERROR("Failed to validate BO\n");
+			goto unlock_all;
+		}
+	}
+
+	/* Handle the moved BOs */
+	ret = amdgpu_vm_handle_moved(uq_mgr->adev, vm, &exec.ticket);
+	if (ret) {
+		DRM_ERROR("Failed to handle moved BOs\n");
+		goto unlock_all;
+	}
+
+	ret = amdgpu_eviction_fence_replace_fence(fpriv);
+	if (ret)
+		DRM_ERROR("Failed to replace eviction fence\n");
+
+unlock_all:
+	drm_exec_fini(&exec);
+	return ret;
+}
+
+static void amdgpu_userqueue_resume_worker(struct work_struct *work)
+{
+	struct amdgpu_userq_mgr *uq_mgr = work_to_uq_mgr(work, resume_work.work);
+	int ret;
+
+	mutex_lock(&uq_mgr->userq_mutex);
+
+	ret = amdgpu_userqueue_validate_bos(uq_mgr);
+	if (ret) {
+		DRM_ERROR("Failed to validate BOs to restore\n");
+		goto unlock;
+	}
+
+	ret = amdgpu_userqueue_resume_all(uq_mgr);
+	if (ret) {
+		DRM_ERROR("Failed to resume all queues\n");
+		goto unlock;
+	}
+
+unlock:
+	mutex_unlock(&uq_mgr->userq_mutex);
+}
+
 static int
 amdgpu_userqueue_suspend_all(struct amdgpu_userq_mgr *uq_mgr)
 {
@@ -486,6 +602,9 @@ amdgpu_userqueue_suspend_worker(struct work_struct *work)
 	/* Cleanup old eviction fence entry */
 	amdgpu_eviction_fence_destroy(evf_mgr);
 
+	/* Schedule a work to restore userqueue */
+	schedule_delayed_work(&uq_mgr->resume_work, 0);
+
 unlock:
 	mutex_unlock(&uq_mgr->userq_mutex);
 }
@@ -508,6 +627,7 @@ int amdgpu_userq_mgr_init(struct amdgpu_userq_mgr *userq_mgr, struct amdgpu_devi
 	/* This reference is required for suspend work */
 	fpriv->evf_mgr.ev_fence->uq_mgr = userq_mgr;
 	INIT_DELAYED_WORK(&userq_mgr->suspend_work, amdgpu_userqueue_suspend_worker);
+	INIT_DELAYED_WORK(&userq_mgr->resume_work, amdgpu_userqueue_resume_worker);
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
index 8b3b50fa8b5b..d035b5c2b14b 100644
--- a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
+++ b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
@@ -76,6 +76,7 @@ struct amdgpu_userq_mgr {
 	struct amdgpu_device		*adev;
 
 	struct delayed_work		suspend_work;
+	struct delayed_work		resume_work;
 	int num_userqs;
 };
 
-- 
2.45.1